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THE EFFECTS OF ORGANIC AND INORGANIC NITROGEN FERTILIZER
ON THE MORPHOLOGY AND ANATOMY
OF INDUSTRIAL FIBRE HEMP (CANNABIS SATIVA L.)
GROWN IN NORTHERN BRITISH COLUMBIA, CANADA
by
Charlene Forrest
B.Sc., University of Northern British Columbia, 2000

THESIS SUBMITTED IN PARTIAL FULFILMENT OF
THE REQUIREMENTS FOR THE DEGREE OF
MASTER OF SCIENCE
in
NATURAL RESOURCES AND ENVIRONMENTAL STUDIES

THE UNIVERSITY OF NORTHERN BRITISH COLUMBIA
April 2004

© Charlene Forrest, 2004

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Abstract
The effect of organic and inorganic nitrogen fertilizer on the morphology and
anatomy of Cannabis sativa var. fédrina was investigated in hoth a greenhouse and field
setting in Northern British Columbia. Plots (90 stems/m^) treated with 0, 75, 150 or 300 kg
N/ha of inorganic nitrogen or fishmeal, bloodmeal or sea star organic fertilizer were also
replicated with 90 kg inorganic PaOs/ha application. The application of 150 and/or 300 kg
N/ha of any nitrogen fertilizer type benefited field-grown plant morphology, secondary
phloem fibre and xylem development, while greenhouse-grown plant morphology, secondary
phloem fibre and xylem were positively influenced by 90 kg PiO^/ha. Primary phloem fibre
characteristics of hoth greenhouse and field-grown plants were benefited by the absence of
either nitrogen or phosphorus fertilizer. This study determined that organic can be used in
place of inorganic nitrogen fertilizer for the production of a majority of fibre characteristics
of C. sativa var. fédrina.

11

Table of Contents

Abstract

11

Table of Contents

iii

List of Tables

vi

List of Figures

vii

Acknowledgements

ix

1 Introduction and Objectives

1

2 Literature Review
2.1 History
2.2 Morphology
2.2.1 Root
2.2.2 Stem
2.2.3 Foliage
2.2.4 Floral Characteristics
2.2.4.1 Staminate
2.2.4.2 Pistillate
2.3 Chemicals
2.4 Anatomy
2.4.1 Vascular Tissue Differentiation Factors
2.4.2 Phloem
2.4.2.1 Primary Phloem Fibre
2.4.2.2 Secondary Phloem Fibre
2.4.3 Xylem
2.5 Growth Requirements
2.6 Cultivation Techniques
2.6.1 Stem Density
2.6.2 Nutrients
2.6.3 Pests and Disease
2.7 Fibre Cultivation
2.7.1 Cellulose
2.7.2 Lignin
2.7.3 Plant Variety (Ecotype/Cultivated Race)
2.7.4 Photoperiod
2.7.5 Plant Sex
2.7.6 Stem Density
2.7.7 Stem Height
2.7.8 Nutrients
2.7.8.1 Nitrogen
2.7.8.2 Phosphorus

2
5
5
6
7
8
9
11
12
13
14
15
16
17
18
19
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20
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23
23
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24
25
26
26
29
111

2.1.S3 Potassium
2.7.8.4 Other Elements
2.7.9 Harvest
2.7.9.1 Fibre Removal
2.8 Present Study
2.8.1 Stem Sampling Location and Technique
2.8.2 Fédrina
2.8.3 Organic Agriculture

31
31
32
33
34
35
37

3 Materials and Methods
3.1 Greenhouse Study
3.1.1 Environmental Data
3.1.2 Soil Characteristics
3.1.3 Fertilization
3.2 Field Study
3.2.1 Environmental Data
3.2.2 Soil Characteristics
3.2.3 Fertilization
3.3 Morphological Measurements:Greenhouse andField Study
3.4 Anatomical Measurements: Greenhouseand Field Study
3.5 Statistical Analysis

39
39
40
40
41
41
42
43
43
44
45
45

4 Results
4.1 Morphology of Greenhouse-Grown C. sativa \ar. fédrina
4.1.1 Stems
4.1.2 Intemodes
4.2 Anatomy of Greenhouse-Grown C. sativa war. fédrina
4.2.1 Internodes
4.2.2 Primary Phloem Fibres
4.2.3 Tissue Ratios
4.3 Morphology of Field-Grown C. sativa war. fédrina
4.3.1 Stems
4.3.2 Intemodes
4.4 Anatomy of Field-Grown C. sativa war. fédrina
4.4.1 Intemodes
4.4.2 Primary Phloem Fibres
4.4.3 Tissue Ratios

46

5 Discussion
5.1 Morphology of Greenhouse-Grown C. sativa war. fédrina
5.2 Anatomy of Greenhouse-Grown C. sativa wax. fédrina
5.3 Morphology of Field-Grown C. sativa war. fédrina
5.4 Anatomy of Field-Grown C. sativa war. fédrina
5.5 Physiological Considerations
5.6 Conclusions

65
69
70
73
75
77
78

6 Future Research and Recommendations

78

49
49
51
53
54
57
58
59
63
63

IV

7 Literature Cited
Appendix A
Appendix B
Appendix C
Appendix D

81
Greenhouse Environment Graph
Field Environment Graph
Greenhouse ANOVA Tables
Field ANOVA Tables

88
89
90
102

List of Tables
Table 1

Treatment regime for Cannabis sativa var. fédrina fertilizer
trials in the UNBC greenhouse and Gitsegukla field.

44

Table 2

Fertilizer effect on stem morphology of Cannabis sativa var.
fédrina grown in the UNBC greenhouse.

49

Table 3

Fertilizer effect on third intemode morphology of Cannabis
sativa var. fédrina grown in the UNBC greenhouse.

50

Table 4

Fertilizer effect on third intemode anatomy of Cannabis
sativa var. fédrina grown in the UNBC greenhouse.

52

Table 5

Fertilizer effect on primary phloem fibre anatomy of
Cannabis sativa var. fédrina grown in the UNBC greenhouse.

54

Table 6

Fertilizer effect on tissue ratios of Cannabis sativa var.
fédrina grown in the UNBC greenhouse.

55

Table 7

Fertilizer effect on stem morphology of Cannabis sativa var.
fédrina grown in the Gitsegukla field.

57

Table 8

Fertilizer effect on third internode morphology of Cannabis
sativa var. fédrina grown in the Gitsegukla field.

59

Table 9

Fertilizer effect on third internode anatomy of C an n ate
sativa var. fédrina grown in the Gitsegukla field.

61

Table 10

Fertilizer effect on primary phloem fibre anatomy of
Cannabis sativa var. fédrina grown in the Gitsegukla field.

63

Table 11

Fertilizer effect on tissue ratios Cannabis sativa var. fédrina
grown in the Gitsegukla field.

64

VI

List of Figures

Figure 1

UNBC greenhouse design of Cannabis sativa var. fédrina grown at
90 stems/m^.

40

Figure 2

Gitsegukla field design of Cannabis sativa var. fédrina grown at
90 stems/m^.

42

Figure 3

Cross-section of the third intemode of Cannabis sativa wax. fédrina
stained with TBO.

47

Figure 4

Example of primary phloem fibre shape and lumen size variation
within one treatment (150 kg sea star N/ha + 0 kg P 205 /ha), on
TBO stained cross-sectional images of Cannabis sativa var.
fédrina.

48

Figure 5

Example of secondary phloem fibre variability within one
treatment (0 kg N/ha 4- 0 kg PiOs/ha), on TBO stained crosssectional images of Cannabis sativa var. fédrina.

48

Figure 6

Example of secondary xylem cell shape and wall thickness
variation on TBO stained cross-sectional images of Cannabis
sativa var. fédrina.

48

Figure 7

Interaction effects of nitrogen fertilizer type and phosphoras level
on the intemode fresh/dry weight of Cannabis sativa var. fédrina
in the UNBC greenhouse, n=477.

51

Figure 8

Representation of phosphorus level enhancement of secondary
phloem fibre development on TBO stained cross-sectional images
of UNBC greenhouse grown Cannabis sativa var. fédrina.

53

Figure 9

Interaction effects of nitrogen fertilizer type and phosphoms level
on the primary phloem fibre/total fibre area ratio of Cannabis
sativa var. fédrina in the UNBC greenhouse, n=477.

56

Figure 10

Interaction effects of nitrogen fertilizer type and phosphoras level
on the primary phloem fibre/total fibre volume ratio of Cannabis
sativa var. fédrina in the UNBC greenhouse, n=477.

56

Figure 11

Interaction effects of nitrogen fertilizer type and nitrogen level on
the number of intemodes of Cannabis sativa var. fédrina in the
Gitsegukla field, n=800.

58

V ll

Figure 12

Interaction effects of nitrogen fertilizer type and nitrogen level on
secondary phloem fibre area (mm^)
(n
of Cannabis sativa var. fédrina
in the Gitsegukla field, n=800.

62

Figure 13

Interaction effects of nitrogen fertilizer type and nitrogen level on
secondary phloem fibre volume (mm^) of Cannabis sativa var.
fédrina in the Gitsegukla field, n=800.

62

V lll

Acknowledgements
Thank you to my supervisor, Dr. Jane Young, for her patience and direction
throughout this journey.
I am grateful to my committee. Dr. Lito Arocena, Dieter Ayers and Dr. Hugues
Massicotte, for lending their knowledge to the study, and to Dr. Janet Marsh for contributing
as my external examiner.
Special gratitude is extended to Dave Ryan and the Gitsegukla Economic
Development Corporation for initiating and providing funding for this project. The support of
Dave Forai and funding from the Village of Masset is also appreciated.
My thanks also go to the Northern Land Use Institute of the University of Northern
British Columbia (UNBC) and the National Research Council of Canada for their funding.
Robert Bucher and family offered cultivation knowledge and assistance, and could
not been thanked enough.
I was privileged to share research and laughter with Alysse Hambleton. In the field,
we were loved and looked after by Leroy and Joe the ‘Cannabus’.
Numerous field, greenhouse and laboratory volunteers were instrumental to the
success of this project. I thank Jennifer and Nathan Howard from Gitsegukla, and from
UNBC: Michelle Coyle, Jesse Giesbrecht, Kelly Hambleton, Sophie Kessler, Colin Lacey,
Keith Williams and many students from Dr. Young’s Plant Biology course.
Countless other UNBC faculty, staff and students were helpful along the way, and
they are appreciated.
I was blessed with this project, and am grateful. This thesis is completed and
submitted in honour of Grandad Ryles and Ryles Craig Forrest. Together, and in a short
period of time, we experienced the whole circle of life and learned what truly matters.

IX

1 Introduction and Objectives
The potential of crop cultivation, including industrial fibre hemp (Cannabis sativa
L.), for community economic development was investigated by Dave Ryan and the
Gitsegukla Economic Corporation of Gitsegukla, British Columbia. Dr. Jane Young, from the
Biology Program at UNBC, was asked to assist Mr. Ryan in his endeavours by offering
scientific data on fertilizer, specifically organic, requirements for productive C. sativa fibre
crops in Northern British Columbia. Another goal of this project was to test locally derived
organic fertilizers as the Gitsegukla Economic Corporation anticipated future production of a
fish head meal organic fertilizer, which would also minimize waste in their commercial
fishing (Ryan pers. comm. 1999). With such production still under development, it was
requested that Alaskan Fish Meal (white cod bonemeal) organic fertilizer (Alaska Fish
Fertilizer Company, Renton, Washington) be tested as a nitrogen source.
The village of Masset, Queen Charlotte Islands, British Columbia, supplied a sea star
meal fertilizer, which has been traditionally used on local gardens (Forai pers. comm. 2000).
Sea star is a by-catch product of the commercial fishing industry, and a joint investigation
with the Department of Fisheries and Oceans (DFO) into the feasibility of a commercial sea
star industry was initiated (Forai pers. comm. 2000). A third organic fertilizer. Blood Meal,
was purchased through Gala Green Products Ltd., Grand Forks, British Columbia. All three
organic fertilizers were compared with inorganic nitrogen fertilizer (Evergro Products, Inc.,
Delta, British Columbia) in this study.
To assist Mr. Ryan in meeting the goal, the objective of this thesis was to assess the
effect of nitrogen source and level on morphological and anatomical characteristics of C.
sativa var. fédrina grown in both field and greenhouse settings. Statistical significance of
between treatment effects of three levels of three organic nitrogen fertilizers, one inorganic
1

nitrogen fertilizer and a control were determined for plant height, diameter, weight, cell
dimensions and areas and volumes of the three fibre types: primary phloem, secondary
phloem and xylem. The anatomical component focused on primary phloem fibre, as it is
valued for its length, flexibility, high cellulose content and lower quantity of more easily
removed lignin (Kundu 1941, Van der Werf et al. 1994b, 1995b, Bocsa and Karus 1998,
Correia 1999, Keller et al. 2001, Mediavilla et al. 2001).
The field site for this project was at Gitsegukla and ran adjacent to the Skeena River,
on a field not cultivated for almost 100 years. The greenhouse site was located at the I.K.
Barber Enhanced Forestry Laboratory, UNBC, Prince George, British Columbia. The
greenhouse was used as a “controlled” site to minimize the effect of other factors and to
assess potential influence of different nitrogen fertilizers.
Previous research has focused on the effect of nitrogen level on C. sativa cultivation
(Jordan et al. 1946, Hessler 1947, Ruzsanyi 1970, Ritz 1972, Basso and Ruggiero 1976,
Haralanov and Babayashev 1976, Van der Werf et al. 1994a, 1995a, 1995c, Hoppner and
Menge-Hartmann 1995, Meijer et al. 1995, Van der Werf and Van den Berg 1995, Ivonyi et
al. 1997, Cromack 1998, Scheifele 1999, Amaducci et al. 2000, BCMAF 2000, Lisson and
Mendham 2000, Sankari 2000, Struik et al. 2000, Keller et al. 2001, Mediavilla et al. 2001),
but not on potential differences between those of organic and inorganic fertilizers.

2 Literature Review
2.1 History
Cannabis and Humulus are the only two genera of the Cannabaceae family (Schultes
1970, Steam 1970). Industrial hemp and marijuana share the same genus and species.
Cannabis sativa L., only differing in their variety, which is primarily determined by the

content of THC (ô (delta)-9-tetrahydrocannabinol) (Health Canada 1998, British Columbia
Ministry of Agriculture and Food (BCMAF) 1999). Canadian regulations require that
industrial hemp contain less than 0.3% THC, while marijuana varieties have been known to
contain 8-30% THC (Health Canada 1998, BCMAF 1999).
The word Cannabis has roots in Sanskrit ancient vernacular and although Caspar
Baughin first used the name Cannabis sativa in 1623, Linnaeus created the Cannabis genus
in 1735 (Schultes 1970). Despite the fact that numerous species names have occurred, i.e., C.
chinensis (Delile), C. erretica (Sieve.), C.foetens (Gilib.), C. indica (Lam.), C. lupulus
(Scop.), C. macrosperma (Stokes), C. americana (Pharm. Ex Wehmer.), C. generalis (E.H.L.
Krause), C. gigantea (Crevost), C. ruderalis (Janischevskii), and a hybrid, C.X. interstitia
(Sojak), it is now generally agreed that Cannabis is a monotypic genus with one species.
There are no true morphological or botanical varieties within the species, but instead many
ecotypes and cultivated races exist (Schultes 1970). This point is often ignored as the term
‘variety’ is commonly used in the Cannabis literature.
C. sativa is not only considered to be one of the oldest crops used for fibre, but one of
the first crops to be cultivated by humans (Schultes 1970, Dempsey 1975). Generally
considered an “Old World Plant” and Asiatic in origin, it has been found in tombs dating
back to 8000 BC (Schultes 1970, BCMAF 1999). In China, there is evidence of its use as a
food grain and fibre source 6500 years ago and it is documented in Chinese writings as early
as 2700 BC (Blade et al. 1998, BCMAF 1999). Around 1500 BC, Scythian invaders from
Asia introduced C. sativa to Western Europe (Schultes 1970). The first reports of its
cultivation in the New World occurred in Chile in 1545 (Blade et al. 1998). Introduction into
North America was around the year 1632, by pilgrims of New England (Schultes 1970). C.

sativa has been found growing wild from Iran to southern Siberia and may be one of the most
widely distributed plants, now spread throughout most of the temperate and tropic regions of
the world (Haney and Bazzaz 1970, BCMAF 1999).
Over 50,000 items can be made from C. sativa fibres and seeds (BCMAF 1999).
Fibres have been used to produce fabric, paper, rope, sails, fishing nets, oakum, upholstery
and carpet (Ramey, Jr. 1980, Van der Werf et al. 1996, Fraanje 1997). Until the early 19***
century, paper was made out of rags (worn-out cloths) which were solely C. sativa and Linum
(flax) [occasionally Gossypium (cotton)], therefore, almost all paper in history was made of
the fibres of these two plants (Van Roekel 1994). Sail-powdered navies of the world were
reliant upon the use of fibrous crops such as C. sativa, Corchorus (jute) and Linum, and
farmers of England and American colonies were legislated to dedicate a portion of their land
to the production of C. sativa (Vignon and Garcia-Jaldon 1996, Blade et al. 1998).
Introduction of C. sativa to Canada occurred in Nova Scotia (Francis 1996). The
popularity of C. sativa farming in Eastern and Central Canada rose in the 18* and 19*
centuries (Blade etal. 1998). From 1923 to 1942, the Canadian Department of Agriculture
tested agronomic management, processing and crop improvement techniques in -3 0 locations
across Canada (Blade et al. 1998). High production costs and the increased use of motorized
boats, synthetic fibres and fibre crops grown in the tropics lead to a decline in C. sativa
cultivation (Ramey, Jr. 1980, Vignon and Garcia-Jaldon 1996, BCMAF 1999). In 1938,
cultivation was made illegal under the Canadian Opium and Narcotics Act, although limited
production was granted during World War II (BCMAF 1999). In 1994, a license was granted
for a low-THC C. sativa research plot in southern Ontario. On March 12, 1998, after a 60
year Canadian ban, it became legal to grow 23 varieties of industrial C. sativa under licenses
granted by Health Canada (BCMAF 1999).

2.2 Morphology
2.2.1 Root
C. sativa has a tap root system that includes numerous lateral roots with horizontal
and vertical extensions (Kundu 1941, Dempsey 1975, Bocsa and Karus 1998). Rooting depth
can be influenced by soil characteristics, groundwater level, cultivation technique, sex and
variety (Bocsa and Karus 1998). In well-cultivated, permeable soils with high mineral
content subsoil, taproots can reach depths of 2-2.5 m. In heavy humus or marshy soil,
taproots reach 30-40 cm (Dempsey 1975, Bocsa and Karus 1998). Under ideal conditions,
lateral roots can extend as far as 60-80 cm (Bocsa and Karus 1998).

2.2.2 Stem
C. sativa is an annual dicot (Kundu 1941, Steam 1970, Dempsey 1975). When young,
the succulent stem lignifies rapidly becoming erect, branched, rigid and woody (Kundu 1941,
Dempsey 1975, Fraanje 1997, Bocsa and Karas 1998). Under optimal conditions, seeds
germinate within 3-7 days and growth to the fourth intemode occurs in 2-3 weeks (Clarke
1999, Scheifele 1999). C. sativa can grow 4-10 cm a day and as high as 5 m in its ~110-115
day vegetative period (Dempsey 1975, Bocsa and Karus 1998, Clarke 1999, Scheifele 1999).
Male plants grow 10-15% taller than females, with smaller diameters and fewer branches
(Bocsa and Karus 1998). C. sativa can have 6-11 intemodes, as long as 20-50 cm varying in
length along the stem (Kundu 1941, Dempsey 1975, Mediavilla et al. 1998). Stem diameter
can range from 3.6-60 mm (Jordan et al. 1946, Dempsey 1975, Scheifele 1999). Largediameter stems are more suitable for seed than fibre production while 4-5 mm diameters are
optimal for fibre production (Jordan et al. 1946, Dempsey 1975, Scheifele 1999).
C. sativa stems are obtusely hexagonal, grooved or furrowed, and hollow in most

varieties (Steam 1970, Dempsey 1975, Bocsa and Kams 1998). They are covered by minute,
non-erect, upward-curved glandular hairs (Steam 1970). The stem provides 65-70% of the
total mass of a fully-grown C. sativa plant (Bocsa and Kams 1998). Leaves appear on the
stem, but are shed off in the lower portion as the plant matures (Dempsey 1975).

2.2.3 Foliage
C. sativa plants have epigeous cotyledons at the first node, followed by 7-12 leaf
pairs (Kundu 1941, Mediavilla et al. 1998). Leaf pairs are arranged in decussate (opposite)
phyllotaxy until photoperiod change prompts a transition to altemate arrangement and
subsequent onset of flowering (Kundu 1941, Dempsey 1975, Mediavilla et al. 1998, Clarke
1999, Lisson and Mendham 2000).
Leaves are palmately compound, most commonly with 5-9 leaflets, but their rangecan
be from 3-11 (Steam 1970, Dempsey 1975). The number of leaflets is determined by variety,
position of leaves on the stem and plant age (Bocsa and Kams 1998). The narrow-lanceolate
leaflets have a wedge-shaped base, a coarse, saw-toothed edge and a long pointed tip (Steam
1970). They vary in length from 5-15 cm and 1-2 cm in width (Steam 1970, Dempsey 1975).
There is an average of 4-14 teeth per edge, with sharp points towards the tip of each leaflet.
Oblique leaf veins occur from leaflet midrib to teeth tips (Steam 1970). Leaflets are rough
and dark green on the adaxial surface, but somewhat lighter on the abaxial surface (Dempsey
1975). Numerous hairs cover the surface of the leaflets creating a soft texture (Steam 1970,
Bocsa and Kams 1998). Leaf glandular hairs excrete minimal amounts of THC in their resin
(Bocsa and Kams 1998).
C. sativa laminas are attached to the stem by stiff, 3-15 cm long petioles with
persistent pointed stipules at their base (Kundu 1941, Steam 1970, Dempsey 1975, Bocsa and
6

Karus 1998). Intemode length, and size and complexity of leaves, increase until the midpoint
of the stem where the longest intemode (-18 cm) and the largest leaves are situated (Kundu
1941).
In the vegetative phase, leaf mass can comprise -24-25% of the total plant mass but
by the end of this phase can be reduced to -8-14% due to wind and natural attrition.
Irregularly shaped or coloured leaves commonly develop from fused leaflets, dual-leaf
formation or chlorophyll defects (Boesa and Kams 1998).

2.2.4 Floral Characteristics
C. sativa is sexually dimorphic (Bocsa and Kams 1998). Originally dioecious, it is
also possible to breed monoecious varieties (Bocsa and Kams 1998, Van der Werf et al.
1994a). Experimental modification to decrease daily exposure to light can increase the
occurrence of monoecious plants while prolonged exposure decreases the proportion of
flowering plants, prevents male and monoecious flowering and reduces flowering in female
plants (Dempsey 1975, Van der Werf et al. 1994a). Although monoecious C. sativa yields
fewer flowers and less pollen, the characteristics of monoecious flowers are similar to those
of female dioecious plants (Bocsa and Kams 1998).
It is claimed that male and female plants are morphologically indistinguishable before
flowering (Van der Werf et al. 1994a). However, in dioecious C. sativa, the male (staminate)
plants are taller and narrower, with fewer leaves than female (pistillate) plants, which are
shorter, stockier and house a broad crown of leaves associated with the terminal inflorescence
(Steam 1970, Dempsey 1975, Bocsa and Kams 1998). Male plants have a 4-6 week shorter
vegetative period than females and die after shedding the pollen, while female plants survive
until the fmits are mature (Kundu 1941, Dempsey 1975, Bocsa and Kams 1998). Unlike most

dioecious crops, which have a 1:1 sex ratio, in C. sativa crops female plants predominate
slightly with 53% female and 42% male plants (Bocsa and Karus 1998). The number of male
and female flowers is relatively constant under normal conditions within a single variety, but
may vary between geological races, varieties or environmental conditions (Steam 1970,
Dempsey 1975, Bocsa and Karus 1998). Plant mass for both the male and female plants are
uniform in a fibre crop at regular harvest time, although delayed harvesting results in lower
weight for males (Bocsa and Karus 1998).

2.2.4.1 Staminate
Male flowers can reach 18-30 cm in length as long, loose, multi-branched, clustered
panicles that develop in the axils of leaves either singly, in pairs, or in groups (Steam 1970,
Dempsey 1975, Bocsa and Kams 1998, Clarke 1999). Each inflorescence branch supports
three apetalous florets, one median and two laterals, on bracts or stipules (Dempsey 1975).
Florets have a deeply parted, simple calyx with five yellow-green or red lobes (~5 mm long)
that house five stamens with anthers suspended from long threadlike filaments (Steam 1970,
Dempsey 1975, Boesa and Kams 1998). Anthers have an elongated prism shape prior to
maturation and tum light yellow after maturation. As fibre crops are planted densely to
decrease branching, flowers are restricted to the terminal end of the stem resulting in fewer
flowers per plant than a crop with wide spacing (Bocsa and Kams 1998).
C. sativa is anemophilous (wind pollinated) with dry, floury dense clouds that travel
as far as 12 km and as high as 20-30 m (Steam 1970, Dempsey 1975, Bocsa and Kams 1998,
Clarke 1999). It produces more pollen than any other cultivated plant (BCMAF 1999). At
anthesis, a single male plant can release up to 30-40 g of pollen from terminal pores of the
anther (Dempsey 1975, Boesa and Kams 1998, Mediavilla et al. 1998). The white, papillate
8

or smooth, circular-oblate pollen grains are 25-30 //m in diameter with 2-4 circular germpores (Steam 1970, Dempsey 1975).

2.2.4.1 Pistillate
Female flowers form a dense, club-shaped or erect raceme inflorescence, in close
aggregate pairs on stipules at leaf axils (Steam 1970, Dempsey 1975, Clarke 1999). A
papery, scabrous, green, single-leaf calyx or bract, creates a tubular sheath around the ovary
(Steam 1970, Dempsey 1975, Bocsa and Karas 1998, Mediavilla etal. 1998). The thin
membranous bract excretes resin from the short-stalked or stalkless circular glands of its
slender trichomes (hairs) (Steam 1970, Clarke 1999). The bract surrounds two thin (3-8 mm)
pistils, with fused style and dual-forked stigma, and the ovary, which houses one seed (Bocsa
and Kams 1998, Mediavilla et al. 1998). With pollination, stigmas tum from white to red, but
if pollination is deficient or does not occur, pistils can tum bright white and reach 10-20 mm
(Bocsa and Kams 1998).
Although the fmit of C. sativa is technically an achene, it has also been called a nut
and is most commonly referred to as a ‘seed’. Bracts surround and imprint a mottle on the
hard, thin, net-veined pericarp, which is light brown to dark grey, smooth and somewhat
compressed, orbicular-oval or ellipsoid in shape (Steam 1970, Dempsey 1975, Bocsa and
Karas 1998, Clarke 1999).
The single, oil-rich seed contains a strongly curved embryo with two cotyledons
packed together along one side and the thin radicle along the other side of the starchy
endosperm (Steam 1970, Bocsa and Karas 1998). On average, C. sativa fruits are 2-6 mm
long, 2-4 mm wide and 1-4 mm in diameter weighing 4.7-23.7 mg (Steam 1970, Bocsa and

Karus 1998, Clarke 1999, Oomah et al. 2002). Thousand seed weights average 20 g, with a
range from 3-60 g and monoecious seed averages of 16 g, dioecious averages of 21 g and
fibre varieties ranging from 14-23 g (Dempsey 1975, Clarke 1999). Individual seeds mature
in 3-5 weeks (Mediavilla et al. 1998).
C. sativa seeds contain 25-35% oil, 20-30% carbohydrates, 20-25% protein and 1015% dietary fibre (Deferne and Pate 1996). They are high in essential fatty acids (37%) and
carotene, low in saturated fats and have a favourable balance of 3:1 Q (omega)-6 to Q-3 fatty
acids (Defeme and Pate 1996, BCMAF 1999, Leizer et al. 2000). There is a range from
-2.2:1 to a 3:1 ratio of linoleic to a-linolenic acid (BCMAF 1999, Leizer etal. 2000). Seeds
have <1 mg/g condensed tannin (catechin), <3 mg/g inositolpentaphosphate and <15 mg/g
inositolhexaphosphate (phytic acid) (Matthaus 1997). They also contain phosphoras,
potassium, calcium, magnesium, sulphur, iron, zinc, terpenes, cannabinoids, phenolics
(including methyl salicylate), ^-sitosterol which has hypocholestérolémie properties and
tocopherols which have antioxidant and anticancer properties (Defeme and Pate 1996, Leizer
et al. 2000).
The seed is the only part of C. sativa that has been used for food. Whole seeds are
used in soups or ground into cakes, animal feed, non-dairy cheese, milk and ice cream
(Roulac 1997, BCMAF 1999). There are no known negative effects, or toxicity reports, of
the consumption of seed oil or its cannabinoids (Leizer et al., 2000).
The seed oil can also be used in the manufacturing of fuel, paint, cosmetics, soaps,
detergents, hydraulic oils, lubricants, biofuels, pharmaceuticals, leather and textiles
(Matthaus 1997, BCMAF 1999). The UV-B and UV-C absorbance capacity may make it a
potential source for broad-spectram UV protection (Oomah et al. 2002). Residues arising

10

from manufacturing processes of C. sativa seed oil can also be used in animal feeds
(Matthaus 1997).

2.3 Chemicals
THC (Ô -9-tetrahydrocannabinol) is produced by glandular trichomes and
accumulates in specialized non-cellular, intra-wall secretory cavities (Kim and Mahlberg
1997). It is secreted by epidermal resin glands, which are associated with the glandular hairs
of the leaf, stem and female flowers (Steam 1970, Blade et al. 1998, Bocsa and Kams 1998,
BCMAF 1999, Clarke 1999). It has been suggested that THC offers the plant UV-B
protection, protection from animals, or may work in conjunction with other chemicals to act
as a means of plant recognition to other organisms in the environment (Steam 1970, Kim and
Mahlberg 1997, Blade et at. 1998).
Within a particular variety of C. sativa, the THC content is largely dependent upon
environmental conditions (Bocsa and Karas 1998). At a lower latitude (46° N) or elevation
(200-250 m), the same variety may produce higher levels of THC than at a higher latitude
(55° N) or elevation (500-600 m). There are also differences in the THC levels of individual
geographic races. Central Russian geographical races have intermediate levels of THC, while
Asiatic races have the highest concentrations (Bocsa and Karas 1998).
Oils and other chemicals are also found in C. sativa. Cannabinol occurs in leaves,
flowers and tips of plants (Dempsey 1975). Although concentrations are similar between
male and female plants, the increased foliage of female plants results in higher cannabinol
yields (Argurell 1970). Cannabinol is composed of >95% cannabidiolic acid and <3% ô tetrahydrocannabinolic acid (Argurell 1970). Cannabidiolic acid appears at early growth

11

stages, increases through plant development and is known to have antibiotic activity by the
eighth week of growth (Krejci 1970). Cannabinoids, and their associated terpenes, may play
roles in antidessication, antimicrobial, antifeedant and UV-B pigmentation (Pate 1994).
There are 58 monoterpenes, 38 sesquiterpenes, simple ketones and esters that have also been
isolated in different C. sativa preparations (Ross and ElSohly 1996).

2.4 Anatomy
As in other ‘woody’ annual dicotyledons, a C. sativa stem is composed of epidermis,
cortex, primary phloem, secondary phloem, vascular cambium, secondary xylem, primary
xylem, and pith, which becomes hollow as the plant matures (Kundu 1941, Mauseth 1988,
Raven et al. 1999).
Cortex can be composed of parenchyma, collenchyma and/or sclerenchyma cells
(Mauseth 1988, Raven et al. 1999). Parenchyma cells have a thin primary wall. They provide
plant organs with mechanical strength derived from osmotic-induced turgor pressure.
Parenchyma cells are also involved in synthesis, structure, transport, secretion and
meristematic functions. Collenchyma cells have thick, cellulose rich, primary walls with
plasticity that offers strength during organ elongation and can lignify at its completion. They
are found in dicots, and occur in the margins and ribs of stems, petioles and leaves, often
directly beneath the epidermis hut also in strands or cylinders within the cortex (Mauseth
1988, Raven et al. 1999). There are no examples of use of collenchyma exclusively in fibre
production which relies on high tensile strength (McDougall et al. 1993).
Sclerenchyma cells have continuous graduation in size, shape and function; therefore,
classification of sclerenchyma is divided between conducting and non-conducting
sclerenchyma (Mauseth 1988, Raven etal. 1999). Conducting sclerenchyma are tracheids
12

and vessel elements of the xylem. The secondary walls of each are high in lignin and also
lack protoplasm at maturity, which makes the cells conducive to water conduction. Non­
conducting sclerenchyma can be divided into either fibres or sclereids, i.e., xylary (xylem) or
extraxylary sclerenchyma (Mauseth 1988, Raven et al. 1999). A ‘fibre cell’ is an individual
sclerenchyma cell, a ‘fibre bundle’ is a collection of such cells and the term, ‘fibre’, is a mix
of cells and bundles (Hobson et al. 2001).

2.4.1 Vascular Tissue Differentiation Factors
Plant growth regulators (PGRs) (phytohormones) believed to be involved in vascular
tissue and fibre differentiation include, but are not exclusive to, auxin, gibberellin and
cytokinin (Aloni 1979, Saks etal. 1984, Aloni 1995). Auxin and gibberellin are commonly
associated with vegetative portions of the stem such as the developing buds and leaves, while
cytokinin is found in the roots (Saks et al. 1984, Taiz and Zeiger 1991, Aloni 1995, Raven et
al. 1999).
Auxin is the limiting and controlling factor for phloem and xylem differentiation
(Aloni 1995). Phloem differentiation can occur at low auxin levels, and in the absence of
xylem differentiation, however, xylem differentiation can only occur with higher auxin
levels. The highest ratio of phloem/xylem occurs under optimal cytokinin levels. In the early
stages of vascular differentiation, cytokinin involvement requires the presence of auxin while
in later stages, differentiation can occur in the absence of cytokinin. The presence of
cytokinin increases tissue sensitivity to auxin (Aloni 1995).
Auxin is the main inducing and limiting factor in primary phloem fibre differentiation
(Aloni 1979). Gibberellin is involved, however, unlike auxin, it cannot act alone and requires
the presence of auxin to be involved. Auxin/gibberellin ratios determine the development and
13

size of primary phloem fibres and stem elongation. A high auxin ratio results in rapid fibre
differentiation, thick secondary cell wall development and inhibits stem elongation, while a
high gibberellin ratio enhances fibre, intemode and stem elongation (Aloni 1979).
Cytokinin is a limiting and controlling factor for fibre (particularly xylem)
differentiation, and increases secondary xylem lignification. In the early stages of secondary
xylem fibre differentiation, cytokinin can play either a promotional or inhibitory role
depending on the physiological state of the plant (Saks et al. 1984).
Cannabis research involving PGRs has found gibberellin to be involved in lateral
branch suppression, poor development of root systems and in increased intemode and stem
elongation, fresh and dry weights, bast/core ratios, number of phloem fibres, phloem fibre
diameters and lengths (up to lOx), lignification (Atal 1961) and plant sex differentiation (Atal
1961, Mohan Ram and Jaiswal 1972, Khryanin and Milyaeva 1977).

2.4.2 Phloem
Primary and secondary phloem, composed of parenchyma, sieve tubes, companion
cells and fibres, are located to the outside of the vascular cambium (Mauseth 1988, Raven et
al. 1999). Primary phloem originates from the outer cells of the procambium and secondary
phloem originates from the vascular cambium (Raven et al. 1999). In C. sativa, tissues to the
outside of the vascular cambium are commonly referred to as the bark (Van der Werf et al.
1995b, Keller et al. 2001) or bast (Ramey Jr. 1980, Bocsa and Karus 1998).
C. sativa bast can be 8.7-50.4% of the stem, with 40-68% phloem fibre composed of
8.4-89% primary phloem fibre and 0-45% secondary phloem fibre (de Meijer 1994, 1995,
Van der Werf et al. 1994b, Correia 1999, Scheifele 1999, Kamat 2000, Sankari 2000,
Mediavilla et al. 2001). It contains 60-74% cellulose, 2.9-11% lignin and 10-18%
14

hemicellulose (Ramey Jr. 1980, Bocsa and Karus 1998, Correia 1999, De Jong et al. 1999).
C.

sativa stem quality is primarily determined by phloem fibre content (Van der Werf

et al. 1994b, McDougall et al. 1993, Mediavilla et al. 2001). Phloem fibres function in plant
mechanical support, herbivore and sap-sucking insect protection, and are a major component
of commercial fibres (Mauseth 1988). High phloem fibre yield, with low secondary phloem
fibre content is optimal for both textiles and paper production (Van der Werf et al. 1994b,
Mediavilla et al. 2001). Increase in phloem fibre content reflects greater increase of
secondary rather than primary phloem fibre (de Meijer 1994).

2.4.2.1 Primary Phloem Fibre
During the vegetative stage of C. sativa, the first fibres to be formed are primary
phloem fibres (Mediavilla et al. 2001). This development occurs during the phase of rapid
stem elongation (Sankari 2000). Up to 40 individual thick-walled, multinucleated (7-21)
fibres are arranged in bundles of 100-300 mm average lengths (Kundu 1941, McDougall et
al. 1993, Meijer et al. 1995, Vignon et al. 1996, De Jong et al. 1999, Keller et al. 2001).
Fibres are bound by middle lamella into round, oval, elliptical, rectangular or outwardtapered pyramid-wedge shapes (Kundu 1941, Vignon et al. 1996, Bocsa and Karus 1998).
Fibre bundles are separated by pectin and hemicellulose-rich cortex parenchyma cells
(Vignon and Garcia-Jaldon 1996, Garcia-Jaldon 1998).
Primary phloem fibres are pointed at both ends and reach their final length and double
their cross-sectional area when the internode completes its extension (Kundu 1941). Final
cell lengths of 0.5-25 cm can be 100-1000 times the diameter (13-78 /^m), with 14 fim thick
walls (Kundu 1941, Ramey Jr. 1980, Van der Werf et al. 1994b, Bocsa and Karus 1998,
Correia 1999, De Jong et al. 1999, Kamat 2000, Sankari 2000). Individual cells complete
15

elongation before secondary cell wall development becomes apparent by the third, fourth, or
eighth internode and continues throughout the lifespan of the plant (Kundu 1941, Ramey Jr.
1980, Mediavilla et al. 2001). Thickening of the wall can reduce the lumen to less than 10%
of the cross-sectional area of the cell (McDougall et al. 1993). The original circular shape is
lost when fibre cells are compressed during secondary growth of the stem (Bocsa and Karus
1998). Pits occur between fibres, but not between fibres and parenchyma (Kundu 1941,
McDougall et al. 1993).
Primary phloem fibre length slightly decreases and diameter increases with plant age
(Kamat 2000). Reduction in fibre length is due to increased interwoven lignification and
decreased turgor pressure (Kamat 2000). As the plant matures, lignification increases tensile
strength of the fibres, but reduces break and torque resistance and elasticity (Bocsa and Karus
1998). Most cells die after differentiating, but do not collapse upon drying unlike other fibres
such as those of Gossypium (Ramey Jr. 1980, McDougall et al. 1993).

2.4.2.2 Secondary Phloem Fibre
Uninucleate secondary phloem fibres form tangential bands of 10-40 cells
(McDougall et al. 1993). Fibres average 0.2-2 cm in length with 22 ^m diameter (Kundu
1941, McDougall et al. 1993, Van der Werf et al. 1994b, Sankari 2000). Filling of secondary
phloem fibre cell walls occurs at the time of flower induction (Mediavilla et al. 2001). After
phyllotaxy change, an abrupt increase in secondary phloem fibre is apparent in female plants
(Mediavilla et al. 2001). The proportion of secondary phloem fibre within the phloem
decreases up the stem, but increases with stem diameter and weight (Van der Werf et al.
1994b).

16

2.4.3 Xylem
The tissues between the vascular cambium and the hollow core (part of pith) are
primary and secondary xylem and the remaining pith. Primary xylem originates from the
inner cells of the procambium and secondary xylem originates from the vascular cambium
(Mauseth 1988, Raven et al. 1999). In C. sativa, they are often referred to together as the
hurd or woody core (Dewey and Merrill 1916, Van der Werf et al. 1995b, Bocsa and Karus
1998, De Jong et al. 1999).
Xylem is composed of parenchyma cells, vessel elements, fibre-tracheids and fibre.
Although a graduation of all cell types and their intermediates exist, there are two main
xylem fibre types: libriform fibres, with thicker cell walls and reduced pits, and fibretracheids, an intermediate form (Mauseth 1988, Raven et al. 1999).
Xylem comprises the largest portion of a C. sativa stem (49.6-80%), and its area
increases with plant age (de Meijer 1994, 1995, Vignon et al. 1996, Correia 1999, Cromack
1998, Scheifele 1999, Kamat 2000). As they are less flexible than phloem fibres, the
aggregation of xylem fibres supplies the stem with vertical strength (Bocsa and Karus 1998).
C. sativa xylem contains 34-40% cellulose, 20-25% lignin and 20-35% hemicellulose (Bocsa
and Karus 1998, De Jong et al. 1999).
Xylem fibre cells can be 0.2-1.0 mm long with 0.1-3 //m wall widths and 10-41 /an
diameters (de Meijer 1994, Van der Werf et al. 1995c, Vignon et al. 1996, Bocsa and Karus
1998, Correia 1999, De Jong et al. 1999, Kamat 2000). Fibre lengths can reach 27.5 times
their diameter (De Jong et al. 1999). Male plant fibres can be 20 /an shorter and 2.5 /an
wider, and fibre varieties tend to have wider fibres than non-fibre varieties (de Meijer 1994).
As with phloem fibres, xylem fibre diameters increase and lengths decrease with plant age

17

and the subsequent increased lignification and decreased turgor pressure (Kamat 2000).

2.5 Growth Requirements
One of the main obstacles for hemp cultivation is adequate crop establishment (Struik
et al. 2000). C. sativa's sensitivity to poorly structured or compact soils is particularly
apparent on heavy clay soil types which experience increased crop variability and decreased
growth (BCMAF 1999, Scheifele 1999, Struik et al. 2000). Well-drained loam or loess soils,
with favorable water balance, permeability and nutrient accumulation are optimal. C. sativa
requires a pH between 5.8-7.5, with > pH 6.0 recommended, and pH 7.0-7.5 preferred
(Dempsey 1975, Bocsa and Karus 1998, BCMAF 1999). The same variety grown on pH 6.6
soil can be 30-45 cm higher than grown on pH 6.0 soil (Scheifele 1999). Crops are improved
if grown on a <5% slope of south facing lowland (Bocsa and Karus 1998).
Until seedlings reach 2-3 weeks old, they are both drought tolerant and sensitive to
high soil moisture (Seale et al. 1957, BCMAF 1999, Scheifele 1999). Low moisture levels
can result in mass reduction and hastened maturity, while excess moisture causes death or
plant stunting (BCMAF 1999, Scheifele 1999). C. sativa plants prefer semi-humid conditions
with 250-700 mm of water during the full duration of growth or 125 mm per month
(Dempsey 1975, Bocsa and Karus 1998, BCMAF 1999). Irrigation can increase total biomass
and stem dry matter. Water requirements for this species are lower than both Zea (maize) and
Hibiscus (kenaf) (Amaducci et al. 2000).
Seed germination can begin at 1-2°C soil temperatures, but requires 6-12°C soil
temperatures to germinate within 8-12 days (Bocsa and Karus 1998, BCMAF 2000). Lower
than optimal temperatures may result in delayed or poor emergence (25-50%) (Mediavilla et

18

al. 1998, BCMAF 2000). The optimal air temperature for growth is 13-25°C with rapid daily
growth of 4-6 cm achieved upon daily averages of 16°C (Dempsey 1975, Bocsa and Karus
1998). Seedlings and mature plants can endure frost to -5°C (BCMAF 1999).
C. sativa is a short-day plant, requiring shorter daylengths (<14 hours) to enter its
reproductive phase (Dempsey 1975, Van der Werf et al. 1994a, Bocsa and Karus 1998,
Lisson et al. 2000).

2.6 Cultivation Techniques
2.6.1 Stem Density
Increased crop density results in a greater risk of self-thinning (Van der W erf et al.
1995a). In an even-aged monoculture crop, size inequality increases over time until the onset
of self-thinning which results in decreased inequality (Weiner and Thomas 1986). Plant
competition is usually ‘one-sided’ as a result of competition for light. However, size
inequality also results from the effects of differences in age, genetics, pests, disease and
environmental conditions (Weiner and Thomas 1986).
For fibre, C. sativa can be cultivated at densities between 50-750 stems/m^ (Jakobey
1965, Dempsey 1975). Lower densities (30-90 stems/m^) are capable of maintaining their
density through to harvest, while higher planting densities (180-300 stems/m^) are more
susceptible to self-thinning (Van der Werf et al. 1995e, Lisson and Mendham 2000, Struik et
al. 2000). Higher plant densities result in delayed flowering, thin stems, lower height and
weight, produce lower crop yields and increased susceptibility to disease (Meijer et al. 1995,
Van der Werf et al. 1995c, Van der Werf 1997, Lisson and Mendham 2000, Sankari 2000,
Struik et al. 2000).

19

2.6.2 Nutrients
The highest nutrient demand occurs during the rapid growth phase and can increase
until technical maturation (full flowering) when only the female plants continue to absorb
nutrients until their seeds mature (Bocsa and Karus 1998). C. sativa removes more nutrients
per hectare than Gossypium, Linum, Triticum (wheat), Zea, Secale (rye) or Avena (oats)
(Dempsey 1975). The amount of available nutrients in the soil and the application of
fertilizers can increase C. sativa stem lengths by 50-60% (Bocsa and Karus 1998).

2.6.3 Pests and Disease
Either biotic sources sueh as genetic disposition, fungi, nematodes, parasitic plants,
bacteria and viruses, or abiotic sources such as environmental stress, nutrient defieieney or
pollutants eause C. sativa disease or injury (MePartland 1996a). Different diseases affect
different varieties, growth stages and plants in different geographic locations or climates.
Fungi cause more problems for C. sativa than bacteria. The borer speeies are the most
important insect pests, and mites are the most important non-inseet pests (MePartland
1996a,b). Although -100 diseases and -300 pests, mainly insects, have been identified for C.
sativa, very few are considered serious and rarely cause économie crop loss (MePartland
1996a,b, Bocsa and Karus 1998). Considered pest-tolerant, C. sativa has fewer pests than
many other crops and there are no specific pesticides or herbicides for this species
(MePartland 1996b, BCMAF 1999).
Uniform and healthy C. sativa crops can suppress and be virtually free of weeds
requiring little or no use for herbicides (Hoppner and Menge-Hartmann 1995, Van der Werf
et al. 1995b, Van der Werf et al. 1995c, Van der Werf and Van den Berg 1995, Bocsa and
Karus 1998, BCMAF 1999, Scheifele 1999). One of the most important weed or parasitic
20

plants of C. sativa is broomrape (Orobanche ramosa) (Bocsa and Karus 1998).
Important C. sativa diseases include grey mold {Botrytis cinerea), hemp canker or
white mold {Sclerotinia sclerotiorum), pythium disease (Pythium debaryanum) and hemp
rust (Melampsora cannabina). The most common pests of this plant are the hemp borer
(Grapholita delineand), European com borer (Ostrinia nubilalis), hemp flea (Psylliodes
attenuata), hemp greenfly (JPhorodon cannabis), Bertha armyworm (Mamestra configurata),
lygus plant bug, cutworm, stinkbug, grasshopper, root knot nematode, caterpillar, beetle,
leafminer, slug, rodent and bird (MePartland 1996b, Bocsa and Kams 1998).
There is evidence that C. sativa may offer moderate efficacy as a repellent crop or
botanical pesticide, although ironically, some of the pests it controls are also those of the
plant itself (MePartland 1997). It has also been found to be effective in suppressing soil
borne pathogens such as nematodes (Meloidogyne chitwoodi), fungus (Verticillium dahliae)
and the survival structures (microsclerotia) of Verticillium dahliae (Kok et al. 1994). When
THC is isolated, it has proven pesticide abilities against bacteria and fungi, but its efficacy on
insects is uncertain. It is believed that cannabinoids play a small role and that it is actually the
combination of the effects of the -400 chemicals in C. sativa that provide the pesticide
capability (MePartland 1997).

2.7 Fibre Cultivation
C. sativa fibres are used to manufacture textiles and in the pulp and paper industry to
strengthen paper for bank notes, cigarette paper, religious books, filter paper, coffee filters,
tea bags, specialty non-wovens, insulating paper (electrical condensators), greaseproof
papers, security papers and various specialty art papers (Van Roekel 1994, Van der W erf et
al. 1996, Vignon and Garcia-Jaldon 1996, Johnson 1999, Mediavilla et al. 2001).
21

For textile and paper produetion, the stronger, longer fibres of the phloem, primary
phloem in particular, are more valuable than xylem fibres (Van der Werf et al. 1994b, Bocsa
and Karus 1998, Mediavilla et al. 2001). In paper manufacturing, fibre length is positively
correlated with paper strength (Van der Werf et al. 1994b). However, xylem fibres have also
been used to produce printing, writing and copying paper, in addition to fuel, barnyard litter,
stable bedding and a sawdust substitute (Dewey and Merrill 1916, De Jong et al. 1999).
New C. sativa fibres can be added to enhance old paper for reuse on a high quality
level. Fibres used in newspapers can also be reused to produce paper wool insulation, which
can be recycled further into new material, composted or incinerated with other feedstock
(Fraanje 1997).

2.7.1 Cellulose
The cellulose level of raw material is positively correlated with chemical pulp yield
(Van der Werf et al. 1994b). Cellulose influences pulp viscosity, and high viscosity indicates
strong pulp due to its higher degree of polymerization and reduced susceptibility to acid
hydrolysis (Correia 1999).
Cellulose production increases throughout the life of the plant, but after the lumen of
the cells are filled, encrustation of lignin in cell walls occurs and decreases cellulose quality
(Struik et al. 2000). C. sativa phloem fibres contain more cellulose (64.8-79%) than xylem
fibres (34.5%) (Van der Werf et al. 1995b, Keller et al. 2001). The low cellulose levels of the
xylem may restrict it to mechanical pulping (Bosia 1975).
In C. sativa, the highest cellulose levels occur in upper stem regions and in male
plants with dioecious varieties having higher levels than monoecious varieties (Bedetti et al.
1979, Keller et al. 2001). Nitrogen has been found to have a negligible effect on stem
22

cellulose content (Struik et al. 2000). However, harvest after flowering yields more
favourable cellulose content, as raw material for paper manufacturing (Van der Werf et al.
1994b).

2.7.2 Lignin
Lignin develops in the fibre cell wall at the completion of cell elongation (Keller et
al. 2001). Higher lignin levels are often found in weaker fibres (Hessler 1947). It is difficult
to enzymatically or chemically digest lignin, which makes its removal difficult to do in an
environmentally friendly manner (Van der Werf et al. 1995b, Keller et al. 2001). Harvest
scheduling for fibre should aim for low lignin levels, and the low lignin containing portions
of the stems should he maximized (Keller et al. 2001).
Phloem fibre lignin decreases over the growing season resulting in a lower quantity
(4.3%) of more easily removed lignin than from xylem fibres (20.8%) (Van der Werf et al.
1994b, Correia 1999). Lignin levels in primary phloem fibres are lower than those of
secondary phloem fibres (Kundu 1941, Mediavilla et al. 2001). Due to the low lignin levels,
mechanically and chemically pulped phloem fibre can be characterized as wood free and
opportunities for unbleached or non-chlorine bleached pulp production are higher than for
wood pulp (Van der Werf et al. 1995b, Van Roekel et al. 1995).

2.7.3 Plant Variety (Ecotype/Cultivated Race)
Variety is one of the main factors affecting the proportion of phloem fibre in C. sativa
stems (de Meijer 1994, Van der Werf et al. 1996, Cromack 1998, Sankari 2000). It affects the
proportion of bast, hut not the proportion of core, or the bast hemicellulose or lignin content,
nor is it attributed to hast content decrease with increased stem dry weight (Van der Werf et
23

al. 1994a,b).
Dioecious male plants are more important for fibre production, however, for phloem
fibre in particular, neither dioecious nor monoecious varieties are superior over the other
(Horkay and Bocsa 1996, Bocsa and Karus 1998, Sankari 2000, Mediavilla et al. 2001).
Optimal harvest date is later for late flowering varieties (Van der Werf et al. 1996). In
such varieties, stem growth continues longer, resulting in greater heights (de Meijer and
Keizer 1994, Van der Werf et al. 1996). Stem height is correlated with stem yield (de Meijer
and Keizer 1994), therefore, late- or non-flowering varieties are suggested for fibre
cultivation (Van der Werf et al. 1994a).

2.7.4 Photoperiod
Photoperiod extension does not affect phyllotaxy change, however, at longer
photoperiods flowering will be delayed in females and prevented in male and monoecious
plants (Van der Werf et al. 1994a, Lisson et al. 2000). Decreased allocation of dry matter to
floral parts is apparent by the shorter (~8 times) inflorescence of plants grown in extended
daylengths (Van der Werf et al. 1994a).
Prolonged daylength increases growth rates between flowering and harvest (Van der
Werf et al. 1994a). The prevention of flowering results in increased stem yield, however,
extended daylengths decrease the quality of the stem content (Van der Werf et al. 1994a).
Similarly, the total amount of light during the vegetative period influences fibre quality more
than quantity (Bocsa and Karus 1998).

2.7.5 Plant Sex
Stems of male plants accumulate primary phloem earlier and in higher quantities.
24

However, female stems are stronger due to thicker, stronger phloem fibres and a higher
proportion of secondary phloem fibre which develops earlier than in male stems (Bocsa and
Karus 1998, Mediavilla et al. 2001).

2.7.6 Stem Density
Plant density is positively related to primary phloem content and fibre fineness, but
inversely related to stem diameter, height, weight, crop yield and flowering date (Jakobey
1965, Van der Werf et at. 1995a,c, Van der Werf 1997, Cromack 1998, Correia 1999, Lisson
and Mendham 2000, Sankari 2000, Struik et al. 2000). Although it is claimed that there is no
correlation between total phloem fibre content and stem diameter, primary phloem content is
more affected by stem diameter of dioecious varieties than monoecious varieties (Van der
Werf et al. 1994b, Sankari 2000). Smaller diameter stems (4-5 mm) are particularly suitable
for fibre production (Jordan et al. 1946, Dempsey 1975, Scheifele 1999). It is also claimed
that total phloem content is inversely related to stem dry weight, yet there is no correlation
between total phloem fibre content and stem dry weight (Van der Werf et al. 1994a,b).
Plant density continues to improve stem quality beyond the point of stem yield
increase. Therefore, the optimal plant density for phloem fibre production is higher than the
lowest plant density that offers the maximum stem dry matter yield (Van der Werf et al.
1995c).
Densities of 90, >100 or 110 stems/m^ produce the most optimal C. sativa stem
yields for phloem fibre, while higher densities such as 270 stems/m^ reduce the proportion of
phloem in the stem and increase the proportion of non-fibre components (Van der Werf et al.
1995b, c, Cromack 1998, Lisson and Mendham 2000). Xylem libriform fibre lengths increase
with densities up to 90 stems/m^, but diameters are not affected by plant density (Van der
25

W erfefa/. 1995c).

2.7.7 Stem Height
The main factors affecting the proportion of stem dry matter are flowering date, plant
density and sexual orientation of the crop (Van der Werf et al. 1996). Plants can add mass by
increasing in height, radius or volume of already occupied stem space (Van der Werf et al.
1995a). Stem height is negatively related to plant density, but positively related to stem yield
(de Meijer and Keizer 1994, Struik et al. 2000). Taller plants tend to be later flowering
varieties, male plants and earlier planted stems (de Meijer and Keizer 1994, Bocsa and Karus
1998, Van der Werf and Van den Berg 1995, BCMAF 2000). Variation in stem height and
weight is greater in female plants (Van der Werf and Van den Berg 1995).

2.7.8 Nutrients
2.7.8.1 Nitrogen
Nitrogen is a component of nucleoside phosphates and amino acids and, therefore, is
involved in the formation of nucleic acids and proteins of plant cells. As it is associated with
many plant cell components, a characteristic deficiency symptom is stunted plant growth
(Taiz and Zeiger 1991). In C. sativa, nitrogen absorption increases continuously throughout
the vegetative period until the onset of flowering with daily nitrogen uptake of 3-4 kg N/ha
and a maximum uptake point of 142-256 kg N/ha incorporated into the plant. Increases in
nitrogen uptake occur when nitrogen supply increases (Ivonyi et al. 1997, Hendrischke et al.
1998). During field retting, plant material is easily mineralized with 16% dry matter and 40%
nitrogen (67 kg N/ha) lost and, therefore, concerns of nitrate leaching can exist (Hendrischke
etal. 1998).
26

It is claimed that nitrogen is the most important nutrient for C. sativa growth and stem
yield, and that compared to its absence, and up to a certain level, nitrogen increases plant
height, and both stem and fibre yield (Jordan et al. 1946, Hessler 1947, Ivonyi et al. 1997,
Bocsa and Karus 1998, BCMAF 2000, Struik et al. 2000). Stem yield increase due to
nitrogen occurs regardless of phosphorus or potassium level applied, yet the application of
nitrogen fertilizer results in lower requirements of these elements (Ivonyi et al. 1997).
On low nitrogen soils, nitrogen deficiency may be apparent and the application of
nitrogen fertilizer may result in a significant stem yield and diameter increase which may not
occur on fertile soils (Jordan et al. 1946). Nitrogen fertile soils can produce adequate yields,
and even slightly increased yields compared to fertilizer treatments (Jordan et al. 1946, Struik
et al. 2000). On these soils, nitrogen fertilizer addition presents either a limited or moderate
effect, or no significant yield or height increases (Jordan et al. 1946, Hendrischke et al. 1998,
Struik et al. 2000).
High levels of soil or nitrogen fertilizer can result in no yield increase and even small
yield decreases (Hessler 1947, Hendrischke et al. 1998, Struik et al. 2000). It may increase
stem diameter beyond that favourable for fibre, and ereate greater variability in stem
diameter, height and weight (Jordan et al. 1946, Van der Werf and Van den Berg 1995,
Scheifele 1999). Leafier, succulent growth, increased stem breakage, higher proportions of
female to male stems and enhanced self-thinning (due to higher competition for light than for
nitrogen) can also occur with high nitrogen (Jordan et al. 1946, Van der Werf et al. 1995a,
Van der Werf and Van den Berg 1995, Struik et al. 2000). Increased nitrogen levels create
large stems with thin phloem sections of low fibre quantity and quality, as the fibres are
weaker and coarser (Jordan et al. 1946, Hessler 1947, Bocsa and Karus 1998). The
detrimental effect of even moderately excessive nitrogen levels on fibre quality is also known
27

in Linum research (Jordan et al. 1946).
For C. sativa fibre cultivation, nitrogen has been applied at levels ranging from 3-220
kg N/ha (Jordan etal. 1946, Hessler 1947, Ruzsanyi 1970, Ritz 1972, Basso and Ruggiero
1976, Haralanov and Babayashev 1976, Van der Werf etal. 1994a, 1995a, 1995c, Hoppner
and Menge-Hartmann 1995, Meijer et al. 1995, Van der Werf and Van den Berg 1995,
Ivonyi et al. 1997, Cromack 1998, Scheifele 1999, Amaducci et al. 2000, BCMAF 2000,
Lisson and Mendham 2000, Sankari 2000, Struik et al. 2000, Keller et al. 2001, Mediavilla et
al. 2001). Significant differences between nitrogen level treatment effects that have been
found include greater fibre yields with 56 or 112 kg N/ha treatment than in the absence of a
nitrogen fertilizer application, with 112kg N/ha producing the highest yield (Jordan et al.
1946). Compared to 0 kg N/ha, treatment with 113 kg N/ha in conjunction with 56 kg
P20s/ha results in stem yield increase with the additional combination of 52 kg KiO/ha
resulting in the greatest (20%) increase (Ruzsanyi 1970). Comparing 60 and 120 kg N/ha has
also resulted in no stem yield increase (BCMAF 2000), however, the application of 80 or 160
compared to 0 kg N/ha has presented a stem yield increase (Ivonyi et al. 1997). The
application of 240 kg N/ha did not increase stem yield beyond that achieved by 80 or 160 kg
N/ha treatment (Ivonyi et al. 1997).
Compared to 80 kg N/ha, plants grown with 200 kg N/ha experienced increased stem
yield, radial growth, biomass (Van der Werf et al. 1995a) and variability in height and weight
(Van der Werf and Van den Berg 1995). However, 80 kg N/ha has caused increased bast
content (Van der Werf and Van den Berg 1995), stem height, proportion of stem in the dry
matter, self-thinning rate (Van der Werf et al. 1995a) and ratio of male plants (Van der Werf
and Van den Berg 1995). There were also fewer flowering plants and nodes on the stems
(Van der Werf and Van den Berg 1995).
28

Based on several C. sativa fertilization studies over three years and locations, it was
found that stem yield was greater with increasing nitrogen level treatment from 100, 160 to
220 kg N/ha, however, the effect was only slight and it was concluded that relatively low
levels of nitrogen are adequate for C. sativa fibre crops (Struik et al. 2000). This is
complemented by the suggestion that the nitrogen requirements of C. sativa fibre crops are
not as high as expected and that not only can its application levels be decreased, from 140 to
100 kg N/ha, but also that the phosphorus and potassium levels should be increased
(Scheifele 1999).
When soil nitrogen level needs are supplemented with fertilizer, either liquid or solid
form is acceptable, as the form of fertilizer has no significant effect on stem yield (Basso and
Ruggiero 1975). It has been claimed that starter fertilizer does not significantly affect stem
height, nor does the time of nitrogen fertilizer application significantly affect the percentage
of fibre achieved (Ritz 1972, Scheifele 1999). However, it is also claimed that nitrogen
fertilizer is more effective if applied at or just after sowing followed by one or two
applications, for example, at emergence and at the point of the third leaf pair formation
(Haralanov and Babayashev 1976, Van der Werf et al. 1995c, Mediavilla et al. 1998). Bam
manure treatment has been found to be less effective than synthetic fertilizers for C. sativa
production. Increased moisture improves fertilizer effectiveness and subsequent stem yield
(Ruzsanyi 1970). Inadequate precipitation inhibits nitrogen fertilizer effectiveness (BCMAF
2000).

2.7.S.2 Phosphorus
Phosphorus is a component of metabolic nucleotides, i.e., DNA and RNA. As sugarphosphate, it is involved in respiration, photosynthesis and phospholipid cell membrane
29

composition (Taiz and Zeiger 1991). Until flowering, C. sativa requires phosphorus to aid in
nitrogen-use efficiency, the development, elasticity and tensile strength of fihre cells, bundles
and total fibre yield (Bocsa and Karus 1998). Daily uptake of 0.25-0.64 kg PiOg/ha is
constant throughout the growth of the plant with a maximum uptake point of 52-67 kg
PsOg/ha incorporated into the plant (Ivonyi et al. 1997). Phosphorus has been applied to C.
sativa fibre crops at levels ranging from 18-121.5 kg P205 /ha (Jordan et al. 1946, Hessler
1947, Ruzsanyi 1970, Haralanov and Babayashev 1976, Meijer et al. 1995, Ivonyi et al.
1997, Cromack 1998, Scheifele 1999, BCMAF 2000, Lisson and Mendham 2000, Sankari
2000).
It is claimed that C. sativa is likely able to absorb the small quantity of phosphorus it
needs from the soil and studies have found that, on low phosphorus soils, the application of
phosphorus fertilizer alone can result in decreased stem height and weight (Ruzsanyi 1970,
Ivonyi et al. 1997). It is also claimed that on low nitrogen soils, phosphorus application can
significantly increase fibre yield and that phosphorus requirements are lower when nitrogen
fertilizer is applied (Jordan et al. 1946, Ivonyi et al. 1997).
Studies comparing phosphorus levels have found that compared to 0 kg PiOg/ha,
treatment with 33 kg PzOg/ha produces greater fibre yields (Jordan et al. 1946) and 100 kg
PzOg/ha increases stem yield, but higher levels do not (Ivonyi et al. 1997). Compared to 113
or 169 kg P 205 /ha, treatment with 56 kg P205 /ha in combination with 113 kg N/ha increased
stem yield, with the greatest yield occurring with the additional combination of 52 kg K20/ha
(Ruzsanyi 1970). Similar outcomes have been found when the increase in application from
30 to 60 kg P 205 /ha only resulted in increased yield when combined with 50 kg K20/ha
(BCMAF 2000).

30

2.7.5.3 Potassium
Potassium is involved in plant cell osmotic potential regulation and activation of
respiration and photosynthesis enzymes (Taiz and Zeiger 1991). The potassium uptake of C.
sativa plants increases from germination through to harvest, with the highest uptake
occurring during fibre development when potassium plays a more important role in fibre
quality than phosphorus (Ivonyi et al. 1997, Bocsa and Karus 1998). At the most intensive
point, daily uptake is 3-6 kg KzO/ha with a maximum uptake point of 223-358 kg KaO/ha
incorporated into the plant (Ivonyi et al. 1997). Potassium has been applied to C. sativa fibre
crops at levels ranging from 32.5-300 kg KiO/ha (Jordan et al. 1946, Hessler 1947, Ruzsanyi
1970, Haralanov and Babayashev 1976, Meijer et al. 1995, Cromack 1998, Scheifele 1999,
BCMAF 2000, Lisson and Mendham 2000, Sankari 2000).
As with phosphorus, the absence of nitrogen fertilizer application can result in
increased potassium requirements (Ivonyi et al. 1997). Although no difference has been
found between the effects of 0 and 22 kg KiO/ha treatment on fibre yield (Jordan et al.
1946), when 52 kg KiO/ha is combined with 56 kg P^Og/ha and 113 kg N/ha, stem yield is
greater than with the same combination with 139 kg KzO/ha level substitution (Ruzsanyi
1970). However, it is also believed that higher than required potassium levels can increase
stem yield (Ivonyi et al. 1997), particularly when the nitrogen and phosphorus levels are
equal (BCMAF 2000).

2.7.5.4 Other Elements
Although the role of trace elements in C. sativa growth is limited, it is known that
sulphur, calcium (CaO) and magnesium (MgO) are important for particular crop rotations
(Bocsa and Karus 1998, Scheifele 1999).
31

2.7.9 Harvest
Stem and fibre development increase rapidly until phyllotaxy change when stem
elongation slows and fibre yield decreases (Van der Werf et al. 1994a, Mediavilla et al. 1998,
2001, Keller et al. 2001). It is possible for elongation to continue past flowering, in which
case earlier flowering results in more length acquired during the floral phase, while later
flowering plants extend more before flowering (de Meijer and Keizer 1994). The ideal time
to harvest for fibre is when dioecious male plants flower (Seale et al. 1957, Jakobey 1965,
Bocsa and Karus 1998, Mediavilla et al. 1998, 2001). At this point, primary phloem cells
predominate and low lignin levels are advantageous for fibre separation (Keller et al. 2001,
Mediavilla et al. 2001). Fibre quantity may be lower, but quality is higher than at later
harvests (Jakobey 1965). The maximum fibre yields achieved at the end of male flowering
and peak of female flowering are due to increased production of secondary phloem fibre
(Mediavilla et al. 2001).
The effect of harvest date on the proportion of bast in the stem is dependent upon
plant variety and density (Van der Werf et al. 1994b). Harvest date affects the chemical
composition of the bast more than the core (Van der Werf et al. 1994b). Delayed harvest
results in increased lignification of fibre, increased production of shorter, higher lignin
containing secondary phloem fibre, and difficult manual separation of fibres (Bocsa and
Karus 1998, Struik et al. 2000, Keller et al. 2001, Mediavilla et al. 2001). High phloem fibre
yield, with low secondary phloem fibre content, is optimal for both textiles and paper
production (Van der Werf et al. 1994b, Mediavilla et al. 2001). An increased proportion of
secondary phloem fibres can result in a reduced total phloem fibre length and a subsequent
reduction in value for paper production (Van der Werf et al. 1994b).
Fibre strength does not vary in different locations along the stem, nor does it decrease
32

with delayed harvest, but the longest fibres are found at the longest internodes (Kundu 1941,
Keller et al. 2001). It is possible for individual fibres to diverge at incoming leaf trace
bundles and continue into the next intemode (Kundu 1941). The top portion of a C. sativa
stem has weaker fibres and a lower phloem fibre content (Hessler 1947, Cappelletto et al.
2001). Phloem fibre in the top 1/3 of the stem is more difficult to separate, therefore, the
lower 2/3 of the stem is more valuable for fibre production and the top portion can be
removed and discarded at harvest (Van der Werf et al. 1994b, Mediavilla et al. 2001).
Variation in stem diameter, height and weight are undesirable for harvesting equipment,
mechanical defoliation and bast and core separation (Van der Werf and Van den Berg 1995).

2.7.9.1 Fibre Removal
Phloem fibres are removed from other stem tissues by retting (Ramey Jr. 1980,
Vignon and Garcia-Jaldon 1996, Kamat 2000, Hobson et al. 2001, Keller et al. 2001). In
field retting, water and microorganisms (fungi) secrete a wide spectmm of enzymes that
decompose the vascular cambium, tannins, pigments, sugars, gums and pectins (Vignon and
Garcia-Jaldon 1996, Johnson 1999, Kamat 2000, Cappelletto etal. 2001). Chemical bonds
between fibres and surrounding tissue are cleanly separated with little damage to the fibres
(Ramey Jr. 1980, Hobson et al. 2001). Cellulose has resistance to decomposition by bacterial
retting and as a result, dew-retted fibre contains -70% cellulose and 30% encrustant material
that varies with variety, growing condition and method of retting (Hessler 1947, Bocsa and
Karus 1998).
As retting is time consuming, can be costly and carry uncertainty, other mechanical
techniques are being tested (Vignon et al. 1996, Hobson et al. 2001, Keller et al. 2001). Fibre
yield, length, distribution and strength are similar for retted and unretted stems (Hobson et al.
33

2001). However, over-retted fibres are weaker (Hessler 1947). Due to less degradation by
microorganisms, cellulosic fibres endure less damage using mechanical fibre removal
(Vignon et al. 1996). Unretted fibre is coarser, with 4% impurities, while retted fibre has only
2%. The light colour and low fungal contamination of unretted fibre is considered a
marketing advantage. Unretted fibre results in a less variable product which may be more
cost effective (Hobson et al. 2001).

2.8 Present Study
2.8.1 Stem Sampling Location and Technique
Previous research has performed fibre measurements at locations such as 5 cm
(Kamat 2000) or 30 cm from the root base (Correia et al. 1998), or at 20-30% of the stem
height for the best approximation of the primary and secondary phloem content (Van der
Werf et al. 1994b). When a stem is divided into ten even segments, the third segment has
been used for xylem and phloem analysis (de Meijer and Van der Werf 1994) and is best
suited for secondary phloem fibre assessment (Van der Werf et al. 1994b).
Specific phloem fibre measurements have been determined using cross-sectional
images (Kamat 2000) and processes of TBO (toluidine blue O) (Mediavilla et al. 2001) and
carmino green of Mirande solution staining of cross-sections, and with gold-palladium coated
samples (Vignon et al. 1996). However, various traditional wood chemistry and manual
dissection techniques have more commonly been used to determine mass fractions of stem
components (Jordan et al. 1946, Hessler 1947, de Meijer 1994, Van der Werf et al. 1994a,
1994b, de Meijer 1995, Cromack 1998, Scheifele 1999, Lisson and Mendham 2000, Sankari
2000, Cappelletto et al. 2001).

34

2.8.2 Fédrina
Fédrina is one of more than 33 different “varieties” of C. sativa, which range in
origin from France, Hungary, Poland, Italy and the former USSR (BCMAF 1999, Ranalli
1999). Some varieties are specialized for seed produetion while others are for fibre. Bred by
M. Amoux and J.P. Mathieu, Fédrina 74 is derived from Fibrimon 24, a monoecious
crossbred variety with high fibre content, and the dioecious Fibridia. Fédrina 74 is a latematuring hybrid variety within the Central and Northern ecotypes category (de Meijer 1995,
Bocsa and Karus 1998).
Originally a monoecious variety, after genetic drift, it now has 15-30% males and a
substantial number of true females within a crop (de Meijer 1995, Van der Werf et al.
1994a). In France, it is grown for use in the paper industry and as a dual-purpose crop for
fibre and seed. Although the fibre quality is considered mediocre, it has sufficient stem/fibre
yield and is a variety recommended for areas with medium soil fertility and poor, rainy
weather (de Meijer 1995, Bocsa and Karus 1998). French varieties typically require a
photoperiod of 14-15.5 hours to enter their reproductive phase, and flower in August after
stem growth slows and ceases. They should be harvested in early September (Van der Werf
et al. 1995c, Van der Werf et al. 1996, Struik et al. 2000).
Initial densities of at least 90 Fédrina stems/m^ provide adequate weed suppression
(Van der Werf et al. 1994a) and self-thinning rates are lower with emergence rates of 86-114
stems/m^ than 186-823 stems/m^ (Meijer et al. 1995). With a planting density of 140
stems/m^, 179 cm heights, 7.4 mm diameters (at base of stem) and 893 g/m^ stem yields can
he achieved (Lisson and Mendham 2000), while planting densities of 160 Fédrina stems/m^
result in -80 stems/m^ at harvest with 194-228 cm heights and 6.7-7.1 mm diameters
(Cappelletto et al. 2001). With a harvest density of 175 Fédrina stems/m^, 165-181 cm
35

heights and 4.09-7.8 t/ha dry matter yield can result (Scheifele 1999).
In Fédrina, the proportion of stem in the aboveground dry matter can reach 78-84%
(Meijer et al. 1995, Van der Werf et al. 1996) and remain constant through to harvest (Meijer
et al. 1995), unaffected by flowering or seed filling (Van der Werf et al. 1996). However, it
has been stated that the bast content is either unaffected by flowering or seed filling (Meijer
et al. 1995) or that it is higher at flowering than when seeds are ripe (Van der Werf et al.
1994b). As a variety, Fédrina has a greater bast content decrease with increased stem dry
weight (Van der Werf et al. 1994a).
Fédrina phloem comprises 22.6% (de Meijer 1995), 20.9-27.5% (Cappelletto et al.
2001) and 32.8% (Lisson and Mendham 2000) stem mass fractions, with 18.9% primary
phloem fibre and 3.6% secondary phloem fibre (de Meijer 1995). Xylem equates to 60.0%
(de Meijer 1995) and 61.3-67.1% (Cappelletto et al. 2001) stem mass fractions. Both phloem
and xylem percentages are lower in the top 1/4 of Fédrina stems than the middle and base
sections (Cappelletto etal. 2001). The hemi-cellulose (14.7-15.6%) and a-cellulose (65.070.5%) levels are highest mid-stem, and the greatest lignin level (3.5-8.9%) is found in the
top region of the stem (Cappelletto et al. 2001).
In Fédrina, extended daylength causes an increased number of nodes with alternate
phyllotaxy and proportion of stem in the aboveground dry matter, but reduced bast content
and inflorescence yield (Van der Werf et al. 1994a). The prevention of flowering by 24 hr
daylengths can increase stem dry matter to 89%, increase leaf matter and reduce
inflorescence dry matter (Van der Werf et al. 1996).

36

2.8.3 Organic Agriculture
Pollution and the increasing cost of chemical fertilizers (especially nitrogen) have
contributed to greater use of organic materials in crop production (Sharma and Mittra 1991).
Organic fertilizers originate from waste and residue of plant and animal life and contain
mineral nutrients in the form of complex organic molecules, while chemical fertilizers
contain inorganic salts (Taiz and Zeiger 1991). It has been proposed that organic farming
practices have lower nitrogen input although not necessarily lower subsequent nitrate
leaching, an important effect of agricultural practice on nitrogen loading in natural water
systems (Kirchmann and Berstrom 2001). There is a belief that organically grown crops are
of higher quality and are healthier for human consumption than those grown with chemical
fertilizers (Taiz and Zeiger 1991).
Organic farming practices avoid the use of synthetic fertilizers, pesticides, growth
regulators and livestock feed additives and instead rely on natural, cultural and biological
controls, crop rotations, crop residues, animal manures, legumes, green manures, off-farm
organic wastes, mechanical cultivation and mineral-bearing rocks to maintain soil fertility
and crop productivity. Practices are employed that measure short-term viability against long­
term environmental sustainability by working with natural processes and cycles to conserve
resources, minimize waste and environmental damage (Hill and MacRae 1992).
Developing countries traditionally used organic materials to maintain and improve
productivity and fertility on agricultural lands until the 1950s when chemical fertilizer use
increased (Parr and Colacicco 1987). They were relatively inexpensive, easily available, less
bulky, and easier to store, transport and apply and often produced dramatic yield
improvement. Increased chemical fertilizer use and the failure to maintain effective soil
conservation practices have resulted in excessive soil erosion, nutrient run off losses and a
37

decrease in stable soil organic matter levels. In turn, this has led to extensive degradation,
decreased crop use efficiency of applied ehemical fertilizers and declined productivity of
agricultural soils in many developing countries (Parr and Colacicco 1987). Organic fertilizers
have been known to eause positive effects on the accumulation of soil organic matter in
reclaimed soils, partieularly within the first few years (Delschen 1999).
Studies have shown that plants derive equal amounts of nitrogen from soil, organic
and inorganic sources (Azam et al. 1985). Soil mineral nitrogen is neither constant in amount
nor location, but is increased by mineralization of organic nitrogen and decreased by
denitrification and immobilization, when nitrate components move downward by leaehing
(Addiscott and Darby 1991).
Most organic sources slowly release nutrients, and compared to inorganic sources,
have a greater residual effect on soil fertility (Parr and Colacicco 1987). Organic nitrogen is
transported in greater amounts to the roots than the shoots, which may explain why, after an
initial nutrient flush, organie fertilizer components are released more slowly, provide a more
continuous supply, leach less and create a residual effect which influences yield responses
from suceeeding erops. When organie material is applied in combination with that of
inorganic, there is ~ 30% less nitrogen loss and crop yield is often higher than when either is
applied alone, whieh suggests that organic materials can increase the effieaey of inorganic
fertilizers (Azam et al. 1985, Parr and Colacicco 1987). Inorganic fertilizer is released and
utilized faster, with more inorganic nitrogen transported to the shoot, indicating that this form
is more mobile than organic nitrogen (Azam et al. 1985). It often has higher macro- and
micronutrient content than organic sources (Parr and Colacicco 1987).
A Canadian organic agriculture movement emerged in the 1950s and both the interest
and practice of various forms of alternative agriculture in Canada are in a state of exponential
38

growth. Consumer demand for organically farmed products has been driven by increased
awareness of correlations between food and health, lifestyles and degradation of the
environment, and the depressed state of the Canadian farm economy (Hill and MacRae
1992).

3 Materials and Methods
The effect of four nitrogen fertilizers on the morphology and anatomy of Cannabis
sativa war. fédrina was studied in two experiments using randomized complete block designs
in both a greenhouse setting at I.K. Barber Enhanced Forestry Laboratory, UNBC, Prince
George, British Columbia (53°53' N 122°48' W) and field site at Gitsegukla, British
Columbia (55° 11' N 127°46' W). In each study area, twenty treatments were replicated in
four blocks for a total of 80 plots of plants grown at a density of 90 stems/m^.

3.1 Greenhouse Study
On July 4 (Day 1), 2000, C. sativa var. fédrina seeds were hand-planted in individual
wooden boxes in the greenhouse (Figure 1). The over-planted (-144 stems/m^) boxes
averaged 82% germination. The 0.0625 m^ sample plots and surrounding 0.125 m buffers
(un-sampled) of all 4 blocks were thinned to 90 stems/m^ on Day 9 (July 12, 2000).
Therefore, each plot contained 6 sample plants, resulting in 24 sample plants for each of the
twenty treatments and a total of 480 greenhouse grown plants sampled.
Phyllotaxy change became apparent by Day 44 (August 16, 2000) and flowering by
Day 52 (August 24, 2000). Plots were harvested by hand from Days 61 to 64 (September 2 to
5, 2000).

39

m

Figure 1. UNBC greenhouse design of Cannabis sativa vsly. fédrina grown at 90
stems/m^. Twenty treatments were replicated over 4 blocks with 24 sample plants per
treatment for total of 480 plants sampled.

3.1.1 Environmental Data
Greenhouse temperature (21°C day, 18°C night) was controlled by a Greystone 420ma Room Temperature Sensor (Greystone Energy Systems Inc., Moncton, New
Brunswick). Relative humidity data was collected by a Siemens Room Relative Humidity
Transmitter (Siemens Building Technologies, Inc., Brampton, Ontario). Sunrise and sunset
data was obtained for Prince George, BC (53°55' N 122°45' W) through the National
Research Council of Canada (Appendix A). Plants were watered daily with tap water.

3.1.2 Soil Characteristics
The greenhouse soil was 3:1 sand and potting soil with a pH of 6.55. Nitrogen,
phosphorus and potassium levels were determined (as per Kalra and Maynard 1991) to be 8

40

kg N/ha, <1 kg P/ha and 126 kg K/ha, respectively.

3.1.3 Fertilization
Greenhouse soil nitrogen and phosphorus levels were considered negligible.
Potassium levels met those of previous C. sativa research (see literature review); therefore,
no potassium fertilizer was added.
Powder or granular forms of inorganic nitrogen fertilizer (ammonium sulphate;
21:0:0; Evergro Products, Inc., Delta, British Columbia) and the two organic fertilizers. Sea
Star fertilizer (5:0:0; Masset, British Columbia) and Alaskan Fish Meal (8:5:1; Renton,
Washington) were applied to the soil at 75,150 or 300 kg N/ha (Table 1). Each treatment was
repeated with the addition of a granular form of inorganic phosphorus fertilizer (treble
superphosphate; 0:45:0; Evergro Products, Inc., Delta, British Columbia) at 90 kg PzOg/ha.
Control treatment (0 kg N/ha) was also repeated with the addition of 90 kg PzOg/ha.
One third of each nitrogen fertilizer treatment was applied one week (Day 16; July 19,
2000) after ~90% germination and two thirds at one month after germination (Day 37;
August 9, 2000). Phosphorus fertilizer was applied to the soil two weeks (Day 25; July 28,
2000) after germination. No herbicides or pesticides were used.

3.2 Field Study
On July 6 (Day 1), 2000, C. sativa var. fédrina was planted with a tractor disc seed
drill in north-south running rows at 18 cm row spacing (Figure 2). Due to a high germination
rate, the Im^ plots and surrounding Im buffers were thinned from -400-500 stems/m^ to 90
stems/m^ (Days 15 to 17; July 20 to 22, 2000). Each plot (including buffer) was separated
from adjacent plots by a Im wide area without seed. Plots contained 10 sample plants;
41

therefore, 40 plants were sampled from each of the twenty treatments for a total of 800
plants.
Phyllotaxy change became apparent by Day 46 (August 20, 2000) and flowering by
Day 53 (August 27,2000). Plots were harvested by hand from Days 66 to 68 (September 9 to

11, 2000).

Figure 2. Gitsegukla field design of Cannabis sativa y sac.fédrina grown at 90 stems/m .
Twenty treatments were replicated over 4 blocks with 40 sample plants per treatment
for a total of 800 plants sampled.

3.2.1 Environmental Data
Daily temperature, precipitation, sunrise and sunset data were obtained through
Environment Canada (Appendix B). Temperature and precipitation data were averaged
between those of Murder Creek (55°31' N 127°28' W) and Suskwa Valley, British Columbia
(55°17' N 127°10' W) and daylength data were recorded in Smithers, British Columbia
(54°49’N 127°11'W).

42

3.2.2 Soil Characteristics
Field soil was determined (as per Kalra and Maynard 1991) to be loam in texture with
nitrogen, phosphorus and potassium levels of 2 kg N/ha, <1 kg P/ha and 263 kg K/ha,
respectively. It had a pH of 6.06.

3.2.3 Fertilization
Field soil nitrogen and phosphorus levels were considered negligible. Potassium
levels met those of previous C. sativa research (see literature review); therefore, no
potassium fertilizer was added.
Powder or granular forms of inorganic nitrogen fertilizer (ammonium sulphate;
21:0:0) and the two organic fertilizers. Blood Meal (15:0:0; Gala Green Products Ltd., Grand
Forks, British Columbia) and Alaskan Fish Meal were applied to the soil at 75, 150 or 300 kg
N/ha (Table 1). Each treatment was repeated with the addition of a granular form of inorganic
phosphorus fertilizer (treble superphosphate) at 90 kg PiOg/ha. Control treatment (0 kg N/ha)
was also repeated with the addition of 90 kg PzOg/ha.
One third of each nitrogen fertilizer treatment was applied one week (Day 18; July 23,
2000) after -90% germination and two thirds at one month after germination (Day 38;
August 12, 2000). Phosphorus fertilizer was applied two weeks after germination (Day 25;
July 30, 2000). No herbicides or pesticides were used.

43

Table 1. Treatment regime for Cannabis sativa \a r. fédrina fertilizer trials in the UNBC
greenhouse and Gitsegukla field.

Greenhouse

Nitrogen Fertilizer Type

0 kg N/ha
0 kg N/ha + 90 kg PiOs/ha
75 kg N/ha

Sea Star Fishmeal Inorganic

75 kg N/ha + 90 kg P205 /ha

Sea Star Fishmeal Inorganic

150 kg N/ha

Sea Star Fishmeal Inorganic

150 kg N/ha + 90 kg P20s/ha Sea Star Fishmeal Inorganic
300 kg N/ha

Sea Star Fishmeal Inorganic

300 kg N/ha + 90 kg P205 /ha Sea Star Fishmeal Inorganic

Field

Nitrogen Fertilizer Type

0 kg N/ha
0 kg N/ha + 90 kg P205 /ha
75 kg N/ha

Bloodmeal Fishmeal Inorganic

75 kg N/ha + 90 kg P205 /ha

Bloodmeal Fishmeal Inorganic

150 kg N/ha

Bloodmeal Fishmeal Inorganic

150 kg N/ha + 90 kg PzOg/ha Bloodmeal Fishmeal Inorganic
300 kg N/ha

Bloodmeal Fishmeal Inorganic

300 kg N/ha + 90 kg P20g/ha Bloodmeal Fishmeal Inorganic

Note: Each of the 20 treatments was replicated in four blocks.

3.3 Morphological Measurements: Greenhouse and Field Study
In the greenhouse, plant height, number of intemodes and length of third intemode
(from soil surface) were measured every 4 days. In the field, plant height measurements
were taken every two weeks. At harvest, for both settings, plant height, number of
intemodes (from soil surface), third intemode length, diameter (at midpoint), fresh weight.

44

dry weight and fresh weight/dry weight ratios were determined for each sample plant.
Sample intemodes were stored lightly wrapped in plastic film, in individual paper bags
within plastic containers at 4°C (EGC cooler. Chagrin Falls, Ohio, USA) with the exception
of sectioning time at room temperature. Dry weights were measured after drying for 4 days
at 65°C (Despatch Oven, Minneapolis, Minnesota).

3.4 Anatomical Measurements: Greenhouse and Field Study
Laboratory techniques followed those of Strieker (2000) and were similar to those of
Mediavilla et al. (2001). Cross-sections were cut with razor blades and stained with TBO
(toluidine blue O). TBO stains lignified tissues blue to blue-green (secondary walls), pectin
stains red-purple (primary walls) and phenolic substances stain blue-green in colour. At the
time of sectioning, xylem depths were measured with ocular micrometers. All cross-sections
were scanned into Northern Exposure^" image analysis software 2.7 (Mississauga, Ontario)
with a microscope-mounted Hitachi Color Video Camera (model VK-C370, Hitachi Ltd.,
Japan). Phloem measurements were made with Northern Exposure^". Phloem and xylem
areas, volumes, and ratios were calculated using the equations for a cylinder. The area in
which the number of primary phloem cells was counted was 0.25 mm long and the width of
the primary phloem tissue (mm) wide. The unit was standardized across treatments to be the
number of primary phloem cells per square millimetre. Primary phloem cell wall width was
measured on the first three cells to the right of the cross-sectional image.

3.5 Statistical Analysis
SPSS™ software (SPSS, Inc., Chicago, Illinois) was used to determine means of

45

measurements and calculated values, analysis of variance (ANOVA) (including interaction
effects) and post-hoc analyses (Tukey-HSD and Bonferroni) differences between fertilizer
treatments.

4 Results
Block effects were experienced in both greenhouse and field trials of Cannabis sativa
var. fédrina. Pest damage to plants was not observed, however, due to shallow application of
the final fishmeal fertilizer treatment, some soil surface mould resulted. Minor fungal gnat
activity was observed on the mouldy surface and ceased with its integration into the soil. In
the field, minimal weed presence was either removed by hand or was naturally suppressed
with increased crop canopy closure.
In the 61 to 64 days of the greenhouse study, plants grew to 19.5 to 154.4 cm heights,
with 5 to 16 intemodes and 0.7 to 15.4 cm long third intemodes of 0.6 to 6.1 mm diameter
(means. Tables 2 and 3). Greenhouse plants were watered daily and maintained at 20.1 to
23.0 °C with 44.6 to 73.9 % relative humidity. Daylength decreased from 17.0 to 13.4 hours,
with phyllotaxy change apparent at 14.8 hours and flowering at 14.2 hours (Appendix A).
Three greenhouse plots established only 5 sample plants, which reduced the total number of
plants sampled per treatment from 24 to 23 for sea star at 150 kg N/ha and 90 kg PiOs/ha,
fishmeal at 75 kg N/ha and 90 kg PiOg/ha and inorganic at 150 kg N/ha and 90 kg PiOg/ha.
In the 66 to 68 days of the field study, plants grew to 20.4 to 193.4 cm heights, with 4
to 16 intemodes and 3.59 to 33.45 cm long third intemodes of 1.4 to 9.5 mm diameter
(means. Tables 7 and 8). Daily precipitation ranged from 0 to 23.4 mm with a total of 156.0
mm. Temperature ranged from 3.0 to 29.3 °C. Daylength decreased from 17.1 to 13.0 hours.

46

with phyllotaxy change apparent at 14.6 hours and flowering at 14.1 hours (Appendix B).
Figure 3 is a cross-sectional image showing epidermis, cortex, primary and secondary
phloem and xylem of the third intemode of a stem. The presence of vascular cambium
retting, causing separation of secondary phloem and xylem, was apparent on some crosssections, and offers a visual presentation of the process as described in the literature review.
Pink stained cell walls of collenchyma in the cortex were well defined in some crosssections. Although not statistically analysed, there was variation observed, even within
treatment groups, for primary phloem fibre cell shape and lumen size (Figure 4), secondary
phloem presence (Figure 5) and secondary xylem cell shape and wall thickness (Figure 6).

Figure 3. Cross-section of the third intemode of Cannabis sativa \ slt. fédrina stained
with TBO. Epidermis is on the outside followed hy cortex (pink), primary phloem (light
purple), secondary phloem (blue) and xylem (blue). Colour refers to that of cell walls.
Retting of vascular cambium and separation of secondary phloem and xylem is visible.
Scale bar = 100 fan.

47

Figure 4. Example of primary phloem fibre shape and lumen size variation within one
treatment (150 kg sea star NÂia + 0 kg PzOg/ha), on TBO stained cross-sectional images
of Cannabis sativa \a r. fédrina. From left image to right, primary phloem fibres appear
more compressed, with thinner cell walls and smaller lumens. Scale bar = 100 fan.

Figure 5. Example of secondary phloem fibre variability within one treatment (0 kg
N/ha + 0 kg PaOs/ha), on TBO stained cross-sectional images of Cannabis sativa var.
fédrina. From left image to right, secondary phloem fibre development appears to
increase. Scale bar = 100 fan.

Figure 6 . Example of secondary xylem cell shape and wall thickness variation on TBO
stained cross-sectional images of Cannabis sativa \sn . fédrina. From left image to right,
xylem cells appear more circular in shape with thicker cell walls. Scale bar = 100 fan.
48

4.1 Morphology of Greenhouse-Grown C. sativa y sir. fédrina
(ANOVA Tables - Appendix B)
4.1.1 Stems
Stem morphology was not significantly affected by either nitrogen fertilizer type or
nitrogen level (Table 2). Plants treated with 90 kg PiOg/ha produced significantly higher
heights and number of internodes compared to those without phosphorus.

Table 2. Fertilizer effect on stem morphology of Cannabis sativa ysar, fédrina grown in
the UNBC greenhouse.
Dependent
Variable
Height (cm)
Number of
intemodes

Control

Sea Star

79.20 (6.24)* 87.85 (3.60)
10.6 (0.3)
11.3 (0.2)

Fishmeal

Inorganic

87.41 (3.60)
11.3 (0.2)

84.75 (3.60)
11.0 (0.2)

0 kg N/ha
75 kg N/ha
150 kg N/ha 300 kg N/ha
Height (cm) 79.20 (6.24) 82.40 (3.60) 88.61 (3.60) 89.01 (3.60)
Number of
10.6 (0.3)
11.0 (0.2)
11.4 (0.2)
11.1 (0.2)
intemodes
____________ O kgPzOs/ha 90 kg P^Og/ha
Height (cm) 77.71 (2.79)a 94.14 (2.79)b
Number of 10.6 (0.1 )a
11.7 (O.l)h
intemodes_____________________________
* Means (SE). Within rows, values followed by a different letter are
significantly different (p < 0.05). Determined by ANOVA, Tukey's HSD
and Bonferroni's post-hoc analyses, n=24.

4.1.2 Internodes
The morphology of internodes was not significantly affected by either nitrogen
fertilizer type or nitrogen level (Table 3). Intemode diameter, fresh weight and fresh/dry
weight ratio were significantly higher in treatments with the addition of 90 kg PzOg/ha
compared to those without phosphoms.
A significant interaction occurred between the effects of nitrogen fertilizer type and
phosphoms fertilizer addition on internode fresh/dry weight ratio (Figure 7). Comparing

49

treatments of 0 and 90 kg PzOg/ha, the most dramatic intemode fresh/dry weight ratio
increase was with inorganic nitrogen fertilizer treatment, and the least dramatic was with the
fishmeal treatment.

Table 3. Fertilizer effect on third intemode morphology of Cannabis sativa yar. fédrina
grown in the UNBC greenhouse.
Dependent
Control
Sea Star
Fishmeal
Inorganic
Variable
Length (cm)
5.33 (0.48)*
5.12(0.27)
5.53 (0.27)
5.26 (0.27)
Diameter (mm)
2.58 (0.21)
3.03 (0.12)
2.84 (0.12)
2.89 (0.12)
Fresh weight (g) 0.415 (0.075) 0.597 (0.043) 0.601 (0.043) 0.565 (0.043)
Dry weight (g)
0.108 (0.022) 0.132(0.013) 0.136(0.013) 0.112(0.013)
Fresh / dry weight 4.73 (0.92)
5.50 (0.53)
5.17(0.53)
5.89 (0.53)
0 kg N/ha
75 kg N/ha
150 kg N/ha 300 kg N/ha
Length (cm)
5.33 (0.48)
5.22 (0.27)
5.57 (0.27)
5.12 (0.27)
Diameter (mm)
2.58 (0.21)
3.00(0.12)
2.94(0.12)
2.81 (0.12)
Fresh weight (g) 0.415 (0.075) 0.548 (0.043) 0.595 (0.043) 0.621 (0.043)
Dry weight (g)
0.108 (0.022) 0.125 (0.013) 0.134 (0.013) 0.120(0.013)
Fresh / dry weight 4.73 (0.92)
5.49 (0.53)
5.71 (0.53)
5.36 (0.53)
0 kg PzOs/ha 90 kg PzOg/ha
Length (cm)
5.49(0.21)
5.12(0.21)
Diameter (mm) 2.43 (0.09)a
3.34 (0.09)h
Fresh weight (g) 0.473 (0.033)a 0.668 (0.033)h
Dry weight (g)
0.135 (0.010) 0.114 (0.010)
Fresh / dry weight 4.09 (0.4 l)a
6.79 (0.4 l)h
* Means (SE). Within rows, values followed by a different letter are
significantly different (p < 0.05). Determined by ANOVA, Tukey's HSD and
Bonferroni's post-hoc analyses, n=24.

50

10.00

O)

I

8.00

t

6.00

Control
Sea Star
Fishmeal

§ 4.00

Inorganic

u_
®

2.00

o
c
g
c

0

90

Phosphorus Level (kg PgOg/ha)

Figure 7. Interaction effects of nitrogen fertilizer type and phosphorus level on the
internode fresh/dry weight of Cannabis sativa yar. fédrina in the UNBC greenhouse,
n=477.

4.2 Anatomy of Greenhouse-Grown C. sativa var. fédrina
(ANOVA Tables - Appendix B)
4.2.1 Internodes
Intemode anatomy was unaffected by either nitrogen fertilizer type or nitrogen level
(Table 4). However, primary phloem fibre area, secondary phloem fibre area and volume,
xylem area and volume, and total fibre area and volume were each significantly higher in
treatments with phosphoms fertilizer application (Table 4, Figure 8).

51

Table 4. Fertilizer effect on third internode anatomy of Cannabis sativa yar. fédrina
grown in the UNBC greenhouse.
Dependent
Variable*
PP area (mm^)
PP volume (mm^)
SP area (mm^)
SP volume (mm^)
X area (mm^)
X volume (mm^)
T area (mm^)
T volume (mm^)

Control

Sea Star

Fishmeal

Inorganic

0.65 (0.04)
0.63 (0.04)
0.63 (0.04)
0.56 (0.06)t
0.89 (0.14)
0.88 (0.08)
1.02(0.08)
0.94 (0.08)
0.35 (0.09)
0.61 (0.05)
0.47 (0.05)
0.52 (0.05)
0.50 (0.21)
0.87 (0.12)
0.61 (0.12)
0.79 (0.12)
0.49 (0.12)
0.84 (0.07)
0.70 (0.07)
0.69 (0.07)
0.80 (0.23)
1.51 (0.14)
1.32 (0.14)
1.24 (0.14)
1.40(0.24)
2.09(0.14)
1.81 (0.14)
1.84 (0.14)
2.18 (0.45)
3.26 (0.26)
2.95 (0.26)
2.97 (0.26)
0 kg N/ha
75 kg N/ha 150 kg N/ha 300 kg N/ha
PP area (mm"')
0.56 (0.06)
0.61 (0.04)
0.63 (0.04)
0.67 (0.04)
PP volume (mm^)
0.89 (0.14)
0.92 (0.08)
0.96 (0.08)
0.96 (0.08)
SP area (mm^)
0.35 (0.09)
0.52 (0.05)
0.51 (0.05)
0.57 (0.05)
SP volume (mm^)
0.50 (0.21)
0.72 (0.12)
0.72 (0.12)
0.83 (0.12)
X area (mm^)
0.49 (0.12)
0.69 (0.07)
0.72 (0.07)
0.82 (0.07)
X volume (mm^)
0.80 (0.23)
1.22 (0.14)
1.31 (0.14)
1.53(0.14)
T area (mm^)
1.40 (0.24)
1.81 (0.14)
1.87 (0.14)
2.06 (0.14)
T volume (mm^)
2.18 (0.45)
3.32 (0.26)
2.87 (0.26)
2.99 (0.26)
0 kg PzOg/ha 90 kg lOs/ha
PP area (mm^)
0.51 (0.03)a 0.74 (0.03)h
PP volume (mm^)
0.91 (0.06)
0.97 (0.06)
SP area (mm^)
0.23 (0.04)a 0.80 (0.04)b
SP volume (mm^)
0.25 (0.09)a
1.22 (0.09)b
X area (mm^)
0.43 (0.05)a
1.00(0.05)b
X volume (mm^)
0.75 (O.lO)a
1.85 (O.lO)b
T area (mm^)
1.17 (0.1 l)a
2.56 (O.ll)b
T volume (mm^)
1.91 (0.20)a 4.04 (0.20)b
* PP, primary phloem fibre; SP, secondary phloem fibre; X, xylem fibre; T, total
fibre (PP+SP+X)
t Means (SE). Within rows, values followed by a different letter are
significantly different (p < 0.05). Determined by ANOVA, Tukey's HSD and
Bonferroni's post-hoc analyses, n=24.

52

&

Figure 8 . Representation of phosphorus level enhancement of secondary phloem fibre
development on TBO stained cross-sectional images of UNBC greenhouse-grown
Cannabis sativa yar. fédrina. Top row: 0 kg P205/ha treatment. Bottom row: 90 kg
PzOg/ha. Left: 0 kg N/ha. Middle: 150 kg N/ha sea star. Right: 300 kg N/ha flshmeal.
Epidermis is on the outside followed hy cortex (pink), primary phloem (light purple),
secondary phloem (blue) and xylem (blue) tissues. Scale bar = 100 jjm.

4.2.2 Primary Phloem Fibres
Primary phloem fibre cell number/mm^ and wall width were both unaffected by either
nitrogen fertilizer type or nitrogen level (Table 5). However, the number of primary phloem
fibre cells/mm^ was significantly higher in treatments without phosphorus and primary
phloem fibre cell wall thickness was significantly higher with the addition of 90 kg PzOg/ha.

53

Table 5. Fertilizer effect on primary phloem fibre anatomy of Cannabis sativa var.
fédrina grown in the UNBC greenhouse.
Dependent
Control
Sea Star
Fishmeal
Inorganic
Variable*
# PP/mm^
3369.8 (211.1)t 2964.7 (121.9) 2908.7 (121.9) 3086.5 (121.9)
PP cell wall
5.6 (0.2)
5.7 (0.1)
5.7 (0.1)
5.5 (0.1)
thickness (//m)
0 kg N/ha
75 kg N/ha
150 kg N/ba
300 kg N/ba
# PP/mm^
3369.8 (211.1) 3113.7(121.9) 2902.3 (121.9) 2943.9 (121.9)
PP cell wall
5.6 (0.2)
5.6 (0.1)
5.7 (0.1)
5.6 (0.1)
thickness (//m)
_______
0 kg PiOs/ha
90 kg PaOs/ba
# PP/mm^
3475.8 (94.4)a 1 5 l l \ (94.4)b
PP cell wall
5.3 (O.l)a
5.9 (O.l)b
thickness (//tn)_______________________________
* PP, primary phloem fibre; SP, secondary phloem fibre; X, xylem fibre; T, total fibre
(PP+SP+X)
t Means (SE). Within rows, values followed by a different letter are signifieantly
different (p < 0.05). Determined by ANOVA, Tukey's HSD and Bonferroni's post-hoc
analyses, n=24.

4.2.3 Tissue Ratios
Control plants had significantly higher primary phloem fibre/total fibre area and
volume ratios than any type of nitrogen fertilizer treatment (Table 6). The absence of
phosphorus fertilizer application produced signifieantly higher primary phloem fibre/total
fibre area and volume ratios, and total phloem fibre/total fibre area and volume ratios.
Conversely, significantly higher secondary phloem fibre/total fibre area and volume,
xylem/total fibre area and volume ratios were produced with the phosphorus treatment.
In significant interactions between the effects of nitrogen fertilizer type and
phosphorus fertilizer application on primary phloem fibre/total fibre area (Figures 9) and
volume (Figure 10) ratios, control or inorganic nitrogen fertilizer treatment ratios show a
more dramatic decrease between the 0 or 90 kg PzOg/ha treatments than sea star or fishmeal
treatments.

54

Table 6. Fertilizer effect on tissue ratios of Cannabis sativa ysvr. fédrina grown in the
UNBC greenhouse.
Control
Sea S tar
Dependent
Fishmeal
Inorganic
Variable*
PP/T area
0.39 (O.Ol)h 0.40 (O.Ol)h
0.47 (0.02)at 0.34 (O.Ol)h
PP/T volume
0.52 (0.04)a 0.31 (0.02)h
0.39 (0.02)h 0.41 (0.02)h
SP/T area
0.19(0.02)
0.27 (0.01)
0.23 (0.01)
0.24 (0.01)
SP/T volume
0.16(0.03)
0.23 (0.02)
0.18(0.02)
0.20 (0.02)
X/T area
0.34 (0.02)
0.39 (0.01)
0.38 (0.01)
0.36 (0.01)
0.32 (0.04)
X/T volume
0.45 (0.02)
0.43 (0.02)
0.39 (0.02)
PP+SP/T area
0.66 (0.01)
0.61 (0.01)
0.62 (0.01)
0.64 (0.01)
PP+SP/T volume 0.68 (0.04)
0.61 (0.02)
0.55 (0.02)
0.57 (0.02)
0 kg N/ha
75 kg N/ha
150 kg N/ha 300 kg N/ha
PP/T area
0.47 (0.02)
0.39 (0.01)
0.36 (0.01)
0.38 (0.01)
PP/T volume
0.52 (0.04)
0.39 (0.02)
0.35 (0.02)
0.38 (0.02)
SP/T area
0.19(0.02)
0.25 (0.01)
0.24 (0.01)
0.25 (0.01)
SP/T volume
0.16 (0.03)
0.20 (0.02)
0.19(0.02)
0.21 (0.02)
0.34 (0.02)
X/T area
0.37 (0.01)
0.39 (0.01)
0.38 (0.01)
0.32 (0.04)
X/T volume
0.40 (0.02)
0.43 (0.02)
0.44 (0.02)
PP+SP/T area
0.66 (0.01)
0.63 (0.01)
0.62 (0.01)
0.61 (0.01)
PP+SP/T volume 0.68 (0.04)
0.60 (0.02)
0.57 (0.02)
0.56 (0.02)
0 kg PiOg/ha 90 kg PiOg/ha
PP/T area
0.47 (O.Ol)a 0.30 (O.Ol)h
PP/T volume
0.53 (0.02)a 0.24 (0.02)h
SP/T area
0.17(0.01)a 0.31 (O.Ol)h
SP/T volume
0.11 (O.Ol)a 0.29 (0.0l)h
X/T area
0.36 (O.Ol)a 0.39 (O.Ol)h
X/T volume
0.36 (0.02)a 0.47 (0.02)h
PP+SP/T area
0.64 (O.Ol)a 0.61 (O.Ol)h
PP+SP/T volume 0.64 (0.02)a 0.53 (0.02)h
* PP, primary phloem fibre; SP, secondary phloem fibre; X, xylem fibre; T,
total fibre (PP+SP+X)
t Means (SE). Within rows, values followed by a different letter are
significantly different (p < 0.05). Determined by ANOVA, Tukey's HSD and
Bonferroni's post-hoc analyses, n=24.

55

I
II
II

II
E

0.70
0.60
0.50
0.40
0.30
0.20
0.10
0.00

Control
Sea Star
- A - Fishmeal
Inorganic

0

90

Phosphorus Level (kg PgOg/ha)

Figure 9. Interaction effects of nitrogen fertilizer type and phosphorus level on the
primary phloem fihre/total fihre area ratio of Cannabis sativa \a r. fédrina in the UNBC
greenhouse, n=477.

0.800
0.700
0.600
0.500
0.400
0.300
0.200
0.100
0.000

Control
Sea Star
Fishmeal
Inorganic

0

90

Phosphorus Level (kg PgOg/ha)

Figure 10. Interaction effects of nitrogen fertilizer type and phosphorus level on the
primary phloem Bbre/total fihre volume ratio of Cannabis sativa \a r. fédrina in the
UNBC greenhouse, n=477.

56

4.3 Morphology of Field-Grown C. sativa var. fédrina
(ANOVA Tables - Appendix C)
4.3.1 Stems
Morphological stem characteristics were significantly affected by nitrogen fertilizer
level, but not by type of fertilizer applied (Table 7). Control treatment resulted in lower stem
height and number of internodes than fertilized treatments. The highest stem height oecurred
with treatment of 150 kg N/ha. Plants without phosphorus treatment had significantly greater
heights compared to plants treated with 90 kg P 205 /ha.
A significant interaction occurred between the effects of nitrogen fertilizer type and
nitrogen level on the number of internodes (Figure 11). Means from the control treatment
were consistently lower than all other treatments. Bloodmeal and fishmeal treatment means
were the highest with 150 kg N/ha, while the highest inorganic treatment mean was at 75 kg
N/ha.

Table 7. Fertilizer effect on stem morphology of Cannabis sativa var. fédrina grown in
tbe Gitsegukla field.
Dependent
Variable
Height (em)
Number of
intemodes
Height (cm)
Number of
intemodes

Control

Bloodmeal

Fisbmeal

Inorganic

97.13 (5.54)*
9.5 (0.2)

121.08 (3.20)
10.3(0.1)

127.07 (3.20)
10.3 (0.1)

130.43 (3.20)
10.4 (0.1)

0 kg N/ba
97.13 (5.54)a
9.5 (0.2)a

150 kg N/ba 300 kg N/ba
75 kg N/ba
115.61 (3.20)b 137.29(3.20)0 125.69 (3.20)b
10.2(0.1)b
10.6 (O.l)b
10.2 (0.1 )b

0 kg PzOs/ba 90 kg PzOg/ba
128.48 (2.48)a 118.09 (2.48)b
10.4 (0.1)
10.2 ( 0 . 1)

Height (cm)
Number of
intemodes
* Means (SE). Within rows, values followed by a different letter are
significantly different (p < 0.05). Determined by ANOVA, Tukey's HSD and
Bonferroni's post-hoe analyses, n=40.

57

c

•Control
•Bloodmeal

10.5 —
10.0

•Fishmeal
■Inorganic

0

9.5 —

1E 9.0 —
3

z

8.5 —
0

75

150

300

Nitrogen Level (kg N/ha)

Figure 11. Interaction effects of nitrogen fertilizer type and nitrogen level on the
number of internodes of Cannabis sativa yar. fédrina in the Gitsegukla field, n=800.

4.3.2 Internodes
Morphological intemode characteristics were significantly affected by nitrogen
fertilizer level, but not by fertilizer type (Table 8). Intemode diameters from the 150 or 300
kg N/ha treatments were significantly higher than those of 0 or 75 kg N/ha. Intemode fresh
weights were significantly higher with treatments of 150 or 300 kg N/ha compared to control.
Plants without phosphoms treatment possessed significantly higher intemode diameters,
fresh and dry weights.

58

Table 8. Fertilizer effect on third internode morphology of Cannabis sativa var. fédrina
grown in the Gitsegukla field.
Dependent
Control
Fishmeal
Inorganic
Bloodmeal
Variable
Length (cm)
10.75 (0.74)* 10.58 (0.43)
11.34 (0.43)
11.71 (0.43)
Diameter (mm) 4.12 (0.22)
4.77 (0.13)
4.85 (0.13)
4.47 (0.13)
Fresh weight (g) 1.461 (0.236) 2.091 (0.136)
2.438 (0.136) 2.424 (0.136)
Dry weight (g) 0.244 (0.040) 0.206 (0.023)
0.254 (0.023) 0.275 (0.023)
Fresh/dry weight 6.15 (1.33)
10.11 (0.77)
10.45 (0.77)
11.59 (0.77)
0 kg N/ha
75 kg N/ha
150 kg N/ha 300 kg N/ha
Length (cm)
10.75 (0.74)
11.15(0.43)
10.83 (0.43)
11.65 (0.43)
Diameter (mm) 4.12 (0.22)a
4.93 (0.13)b
4.73 (0.13)h
4.44 (0.13)a
Fresh weight (g) 1.461 (0.236)a 1.981 (0.136)ab 2.603 (0.136)0 2.369 (0.136)bc
Dry weight (g) 0.244 (0.040) 0.228 (0.23)
0.275 (0.023) 0.232 (0.023)
Fresh/dry weight 6.15 (1.33)
9.80 (0.77)
10.69 (0.77)
11.65 (0.77)
0 kg PaOs/ha 90 kg PaOs/ha
Length (cm)
11.46 (0.33)
10.87 (0.33)
Diameter (mm) 4.83 (0.10)a
4.45 (O.lO)b
Fresh weight (g) 2.462 (0.105)a 2.002 (0.105)b
Dry weight (g) 0.281 (0.018)a 0.209 (0.018)b
Fresh/dry weight 9.58 (0.60)
10.94 (0.60)
* Means (SE). Within rows, values followed by a different letter are significantly
different (p < 0.05). Determined by ANOVA, Tukey's HSD and Bonferroni's
post-hoc analyses, n=40.

4.4 Anatomy of Field-Grown C. sativa var. fédrina
(ANOVA Tables - Appendix C)

4.4.1 Internodes
Nitrogen fertilizer type was found to significantly affect three anatomical
characteristics, two of which did not differentiate in post-hoc tests: primary phloem fibre area
and volume (Table 9). The area of primary phloem fibre was higher with fishmeal or
inorganic nitrogen fertilizer treatment and lower with bloodmeal or control treatment. The
volume of primary phloem fibre was highest in the control and lowest in the bloodmeal
treatment. Total fibre volume was significantly higher with fishmeal or inorganic nitrogen

59

fertilizer treatment compared to control. Xylem area and volume were significantly higher
with 150 or 300 kg N/ha treatment compared to control. Total fibre volume was significantly
higher in the 150 kg N/ha treatment than the control. Primary phloem fibre area, xylem area
and volume and total fibre area and volume were all significantly higher with the absence of
phosphorus fertilizer compared to treatments with phosphorus.
There were significant interactions between the effects of nitrogen fertilizer type and
nitrogen level for secondary phloem fibre area (Figure 12) and volume (Figure 13). Means
from the control treatment were consistently lower than all other treatments. Bloodmeal and
fishmeal treatment means were highest with 150 kg N/ha, while the highest inorganic
treatment mean was at 75 kg N/ha.

60

Table 9. Fertilizer effect on third intemode anatomy of Cannabis sativa yar. fédrina
grown in the Gitsegukla field.
Dependent
Variable*
PP area (mm^)
PP volume (mm^)
SP area (mm^)
SP volume (mm^)
X area (mm^)
X volume (mm^)
T area (mm^)
T volume (mm^)

Control

Bloodmeal

Fishmeal

Inorganic

1.13(0.08)1$ 1.12(0.05)$
1.29 (0.05)$ 1.23 (0.05)$
2.90 (0.24)$
2.30(0.14)$
2.78 (0.14)$ 2.75 (0.14)$
0.59 (0.05)
0.54 (0.05)
0.64 (0.05)
0.35 (0.09)
0.38 (0.13)
0.70 (0.08)
0.59 (0.08)
0.75 (0.08)
0.96 (0.15)
1.48 (0.09)
1.37(0.09)
1.59 (0.09)
2.31 (0.50)
4.11 (0.29)
3.63 (0.29)
4.36 (0.29)
2.44 (0.30)
3.52 (0.17)
3.29 (0.17)
3.04(0.17)
5.58 (0.7 l)a
6.53 (0.41)ah 7.88 (0.41)h 7.56 (0.4l)h
0 kg N/ha
75 kg N/ha
150 kg N/ha 300 kg N/ha
PP area (mm^)
1.13(0.08)
1.16(0.05)
1.16(0.05)
1.30 (0.05)
PP volume (mm^) 2.90 (0.24)
2.54 (0.14)
2.83 (0.14)
2.45 (0.14)
SP area (mm^)
0.54 (0.05)
0.66 (0.05)
0.58 (0.05)
0.35 (0.09)
SP volume (mm^) 0.38 (0.13)
0.77 (0.08)
0.65 (0.08)
0.62 (0.08)
X area (mm^)
0.96 (0.15)a
1.31 (0.09)ah 1.62 (0.09)h 1.51 (0.09)h
X volume (mm^)
2.31 (0.05)a
3.38 (0.29)ah 4.61 (0.29)h 4.10 (0.29)h
T area (mm^)
3.57 (0.17)
3.27 (0.17)
2.44 (0.30)
3.00(0.17)
T volume (mm^)
5.58 (0.7l)a
6.54 (0.41)ah 8.22 (0.41)h 7.21 (0.41)ah
0 kg PiOs/ha 90 kg P^Og/ha
PP area (mm^)
1.28 (0.04)a
1.13 (0.04)h
2.49(0.11)
PP volume (mm^) 2.79 (0.11)
053 (0.04)
0.61 (0.04)
SP area (mm^)
0.59 (0.06)
SP volume (mm^) 0.71 (0.06)
1.56 (0.07)a
X area (mm^)
1.30(0.07)h
3.43 (0.22)h
4.29 (0.22)a
X volume (mm^)
3.44 (0.13)a
T area (mm^)
2.96 (0.13)h
7.91 (0.32)a
6.51 (0.32)h
T volume (mm^)
* PP, primary phloem fibre; SP, secondary phloem fibre; X, xylem fibre; T, total
fibre (PP+SP+X)
t Means (SE). Within rows, values followed by a different letter are significantly
different (p < 0.05). Determined by ANOVA, Tukey's HSD and Bonferroni's
post-hoc analyses, n=40.
$ Significant ANOVA results (p < 0.05) but no differentiation with post-hoc
analyses.

61

£
n
il

i “î
Û.

s
(0

■o
c
o
u
w

0.90
0.80
0.70
0.60
0.50
0.40
0.30
0.20
0.10
0.00

—

Control

— Bloodmeal
—A—Fishmeal
Inorganic

0

75

150

300

Nitrogen Level (kg N/ha)
Figure 12. Interaction effects of nitrogen fertilizer type and nitrogen level on secondary
phloem fibre area (mm^) of Cannabis sativa \ ay. fédrina in the Gitsegukla field, n=800.

1.20
£
n
iZ
1.00
E
Q> I 0.80

•Control
Bloodmeal

® 0.60
5
C
0

1

•Fishmeal

■5 0.40

Inorganic

0.20
0.00
0

75

150

300

Nitrogen Level (kg N/ha)
Figure 13. Interaction effects of nitrogen fertilizer type and nitrogen level on secondary
phloem fihre volume (mm^) of Cannabis sativa \ a y . fédrina in the Gitsegukla field,
n=800.

62

4.4.2 Primary Phloem Fibres
The number of primary phloem fihres/mm^ and fibre wall thickness were both
unaffected by either nitrogen fertilizer type or nitrogen level (Table 10). However, a
significantly higher number of primary phloem fibres/mm^ was produced in treatments with
the presence of 90 kg P^Og/ha.

Table 10. Fertilizer effect on primary phloem fibre anatomy of Cannabis sativa var.
fédrina grown in tbe Gitsegukla field.
Dependent
Control
Bloodmeal
Fisbmeal
Inorganic
Variable*
# PP/mm^
2163.4 (59.9)
2064.5 (59.9)
2350.6 (103.7)t 2208.8 (59.9)
PP cell wall
6.8 (0.3)
6.5 (0.2)
6.7 (0.2)
6.9 (0.2)
thickness (/mi)
0 kg N/ba
75 kg N/ba
150 kg N/ha
300 kg N/ba
# PP/mm^
2350.6 (103.7) 2197.8 (59.9)
2169.4 (59.9)
2069.6 (59.9)
PP cell wall
6.7 (0.2)
6.8 (0.3)
6.7 (0.2)
6.6 (0.2)
thickness (/mi)
0 kg PzOg/ha
90 kg PzOg/ba
# PP/mm^
2087.7 (46.4)a 2244.5 (46.4)b
PP cell wall
6.8 (0.1)
6.6 (0.1)
thickness (/mi)_______________________________
* PP, primary phloem fibre; SP, secondary phloem fibre; X, xylem fibre; T, total
fibre (PP+SP+X)
t Means (SE). Within rows, values followed hy a different letter are significantly
different (p < 0.05). Determined hy ANOVA, Tukey's HSD and Bonferroni's
post-hoc analyses, n=40.

4.4.3 Tissue Ratios
Intemode tissue ratios were unaffected hy either nitrogen fertilizer type or the
addition of phosphorus fertilizer, hut were affected hy nitrogen level (Table 11). Primary
phloem fihre/total fihre area and volume ratios were significantly higher for the control
treatment plants compared to those with any level of nitrogen treatment. Xylem/total fibre
area and volume ratios were significantly higher with 300 kg N/ha treatment compared to 75

63

kg N/ha, and ail levels of nitrogen treatment were significantly higher than the control. Total
phloem fibre/total fibre area and volume ratios were significantly higher for the control
compared to all levels of nitrogen treatment, and 75 kg N/ha was higher than 300 kg N/ha
treatment.

Table 11. Fertilizer effect on tissue ratios of Cannabis sativa \a r. fédrina grown in the
Gitsegukla field.
Dependent
Control
Fishmeal
Inorganic
Bloodmeal
Variable*
PP/T area
0.38 (0.01)
0.38 (0.01)
0.52 (0.02)t 0.38 (0.01)
PP/T volume
0.37 (0.02)
0.37 (0.02)
0.60 (0.03)
0.37 (0.02)
SP/T area
0.12(0.02)
0.17(0.01)
0.18(0.01)
0.17(0.01)
SP/T volume
0.05 (0.01)
0.09 (0.01)
0.09 (0.01)
0.09 (0.01)
X/T area
0.37 (0.01)
0.44 (0.01)
0.45 (0.01)
0.45 (0.01)
0.54 (0.02)
0.54 (0.02)
X/T volume
0.35 (0.03)
0.54 (0.02)
PP+SP/T area
0.55 (0.01)
0.56 (0.01)
0.63 (0.01)
0.56 (0.01)
0.46 (0.02)
0.46 (0.02)
PP+SP/T volume 0.66 (0.03)
0.46 (0.02)
150 kg N/ha 300 kg N/ha
0 kg N/ha
75 kg N/ha
PP/T area
0.52 (0.02)a 0.40 (O.Ol)h 0.37 (O.Ol)h 0.36 (O.Ol)h
PP/T volume
0.60 (0.03)a 0.42 (0.02)h 0.36 (0.02)h 0.34 (0.02)h
SP/T area
0.12(0.02)
0.18(0.01)
0.18 (0.01)
0.17 (0.01)
0.09 (0.01)
0.09 (0.01)
SP/T volume
0.05 (0.01)
0.09 (0.01)
X/T area
0.37 (O.Ol)a 0.43 (O.Ol)h 0.45 (O.Ol)hc 0.46 (O.Ol)c
X/T volume
0.35 (0.03)a 0.50 (0.02)h 0.55 (0.02)hc 0.57 (0.02)c
PP+SP/T area
0.63 (O.Ol)a 0.57 (O.Ol)h 0.55 (O.Ol)hc 0.54 (O.Ol)c
PP+SP/T volume 0.66 (0.03)a 0.50 (0.02)h 0.45 (0.02)hc 0.43 (0.02)c
0 kg PzOg/ha 90 kg PiOg/ha
PP/T area
0.39 (0.01)
0.40 (0.01)
PP/T volume
0.38 (0.02)
0.40 (0.02)
SP/T area
0.17(0.01)
0.17 (0.01)
SP/T volume
0.09 (0.01)
0.09 (0.01)
X/T area
0.44 (0.01)
0.43 (0.01)
X/T volume
0.53 (0.01)
0.51 (0.01)
PP+SP/T area
0.56 (0.01)
0.57 (0.01)
PP+SP/T volume 0.47 (0.01)
0.49 (0.01)
* PP, primary phloem fibre; SP, secondary phloem fibre; X, xylem fibre; T,
total fibre (PP+SP+X)
t Means (SE). Within rows, values followed by a different letter are
significantly different (p < 0.05). Determined by ANOVA, Tukey's HSD and
Bonferroni's post-hoc analyses, n=40.

64

5 Discussion
This thesis concentrated on literature related to Cannabis sativa war. fédrina fibre
cultivation, but it is appreciated that the incorporation of fertilizer research on other fibre
producing plants could only be beneficial. Comparison with results from different C. sativa
studies must take into account that its morphological and anatomical characteristics are
affected by many different factors, as discussed in the literature review. These include plant
variety, sex, age, height, diameter, weight, yield, stem portion, self-thinning rate, and
phyllotaxy change and flowering date. Cultivation parameters such as planting date, soil pH
and type, moisture levels, daylength, nutrients such as nitrogen, phosphorus and potassium,
density, harvest date and retting technique also influence C. sativa morphological and
anatomical characteristics.
The variation in C. sativa sampling and measurement techniques must also be
considered. This study analysed TBO stained cross-sections at the midpoint of the third
internode from the soil surface to determine fibre composition of the stems. In regard to the
number of intemodes produced on both greenhouse and field stems, this sampling location
was comparable to those of other studies which assessed fibre content at -30 cm from the
base (Correia 1999), at 20-30% of the stem height (Van der Werf et al. 1994b), or
approximately the third of ten equal stem segments (de Meijer and Van der Werf 1994).
However, if the length of intemode is considered, the greenhouse stem measurement site
would be below 30 cm (from the base) (Correia 1999) or 20-30% of the stem height (Van der
Werf et al. 1994b).
Previous studies have investigated specific phloem fibre measurements through crosssectional images and processes of TBO, carmino green of Mirande solution stained cross-

65

sections and gold-palladium coated samples. However, various traditional wood chemistry
and manual dissection techniques have more commonly been used to determine mass
fractions of stem components. The present study compared fibre-to-fibre measurements, and
not fibre to wbole stem cross-section measurements. Until different techniques are
specifically compared with each other, their ability to produce comparable fibre proportion
results will be assumed.
The greenhouse trial of this project was intended to serve as a more “controlled
environment” in which to assess the effects of the fertilizer treatments. C. sativa research has
traditionally been conducted in field settings. Of the limited greenhouse research available,
no studies offered results relevant to this present study. Therefore, compared to previous field
studies, stems in this greenhouse study exhibited lower heights and diameters than those of
other C. sativa war. fédrina work (Scheifele 1999, Lisson and Mendham 2000, Cappelletto et
al. 2001), but similar to tbose of other varieties at 60 days of growth (Kamat 2000). Intemode
diameters would be favourable for fibre production (Jordan et al. 1946, Scheifele 1999) and
the number of intemodes was similar to previous research (Mediavilla et al. 1998). In the
field study, results of each noted characteristic conformed to those of previous studies. It is
assumed that with a longer growing period, stems of both trials of this research would have
had increased height and diameter; however, the benefit of such an increase for greater
primary phloem fibre production is questionable.
Plants in the greenhouse tended to have lower heights, intemode lengths, diameters,
fresh and dry weights and fresh/dry weight ratios but similar number of intemodes compared
to field plants; however, none of these characteristics were compared statistically. It would be
interesting to investigate further the differences between greenhouse and field grown plants.
In the present study, the total fibre area of a greenhouse Fédrina intemode was
66

comprised of 61-66% total phloem fibre, 30-47% primary phloem fibre, 17-31% secondary
phloem fibre and 34-39% xylem. In the field, the intemode was composed of 54-63% total
phloem fibre, 36-52% primary phloem fibre, 12-18% secondary phloem fibre and 37-46%
xylem. Therefore, xylem did not generally comprise the largest portion of the stem as
previously claimed (Vignon et al. 1996, Correia 1999). Fédrina studies have found stem
mass fractions of 22.6-32.8% total phloem fibre, 18.9% primary phloem fibre, 3.6-45%
secondary phloem fibre and 60.0-67.1 % xylem (Van der Werf et al. 1994a,b, Meijer 1995,
Lisson and Mendbam 2000, Cappelletto et al. 2001).
With other varieties, cross-section assessments have shown that the stem is comprised
of 20% bast, 50% core and 30% pith fractions (Correia 1999) with 19.29% total phloem fibre
and 77.65% xylem at 60 days of growth and 20.34% and 77.31%, respectively at 120 days of
growth (Kamat 2000). At the time of highest fibre yield there was 65% primary phloem fibre
area, with up to 45% secondary phloem fibre area of the cross-section at the time of flower
induction (Mediavilla et al. 2001). Previous mass fraction assessments on other varieties
have found 19.3-68% phloem fibre composed of 8.4-89% primary phloem fibre, 0-45%
secondary phloem fibre and 49.6-77.7% xylem (de Meijer 1994, Cromaek 1998, Scheifele
1999, Sankari 2000).
This study extrapolated measurements into volumes to offer comparison at another
(third) dimension to the area results, and for future extrapolation of results into potential
yields that may be attained. For example, the grand mean of all treatments results for the
primary phloem fibre volume of the third intemode multiplied by the number of internodes in
the lower 2/3 of the stem suggests that greenhouse plants would produce 0.25 m^ (8.93 ft^,
0.326 yd^) and field plants, 0.66 m^ (23.57 ft^, 0.863 yd^) of primary phloem fibre on a
404,686 m^ (100 acre) field; this would double with two crops per year.
67

Collenchyma was observed on stem cross-sections in this study. There are no
examples of the exclusive use of collenchyma in high tensile strength fibre production
(McDougall et al. 1993), however, the role of collenchyma in the cellulose and lignin
contents of C. sativa bast and its pulp potential should be considered and investigated.
Cultivation conditions of C. sativa var. fédrina grown in both the greenhouse and
field trials of this present study met C. sativa daily temperature requirements (Dempsey
1975, Bocsa and Karus 1998) and this variety’s timing of phyllotaxy change in relation to
photoperiod change (Lisson et al. 2000, Struik et al. 2000) and date of harvest (Van Der
Werf et al. 1996). Greenhouse plants were watered daily, but field plants were not irrigated
and as a result of the climatic conditions, total precipitation was low in the field trial
(Dempsey 1975, Bocsa and Karus 1998, BCMAF 1999).
In both trials, plants in the two centre blocks were more “robust” than those of outer
blocks most likely due to greater exposure to natural light. In the greenhouse, the ventilation
equipment may have caused increased shade, airflow and lower temperatures on the block
parallel to the outer wall. Plants were grown at a density capable of maintaining its
population through to harvest (Struik et al. 2000), however, the mortality of three greenhouse
sample plants before harvest reinforces that the potential of self-thinning should be
considered when growing hemp for fibre.
In this study, one dose of nitrogen fertilizer was applied one week after -90%
germination and a second dose at one month after germination, in a powder or pellet form
just below the soil surface. Phosphorus fertilizer was applied two weeks after germination.
Although nitrogen fertilization schedule does not significantly affect the percentage of C.
sativa fibre (Ritz 1972) or stem height (Scheifele 1999), fertilizer application before sowing,
with subsequent doses during the period of growth (Haralanov and Babayashev 1976,
68

Mediavilla et al. 1998) could be considered. The shallow application of fertilizer resulted in
fishmeal fertilizer soil surface mold; however, with re-integration into the soil, its efficacy
was not expected to be negatively affected (Alaskan Fish Meal pers. comm. 2000). Pre­
sowing fertilizer and, or, liquid fertilizer integration into the soil would be recommended for
future cultivation.

5.1 Morphology of Greenhouse-Grown C. sativa vvac. fédrina
In the greenhouse trial, neither nitrogen fertilizer type nor level significantly affected
C. sativa var. fédrina morphology. This outcome was unexpected as previous research has
documented that nitrogen is the most important nutrient for C. sativa growth and stem yield,
particularly at levels hetween 60-240 kg N/ha which affect stem yield, height, diameter,
number of nodes and weight (Jordan et al. 1946, Hessler 1947, Ruzsanyi 1970, Ivonyi et al.
1997, Van der Werf et al. 1995a, Van der Werf and Van den Berg 1995, Bocsa and Karus
1998, Scheifele 1999, BCMAF 2000, Stmik et al. 2000). If stem height is correlated with
stem yield (Meijer and Keizer 1994) then the results in the present study suggest there would
be no effect of nitrogen fertilizer type or level on stem yield.
The lack of difference between the effects of nitrogen fertilizer type suggests that the
use of organic fertilizer produces outcomes comparable to those of inorganic nitrogen
fertilizer. Benefits of organic fertilizer use are noted in the literature review of this thesis. The
only evidence of previous studies comparing organic and inorganic fertilizers on C. sativa
found barn manure to be less effective than synthetic fertilizer on stem yield (Ruzsanyi
1970). The lack of difference between the effects of nitrogen level suggests that there is the
opportunity to grow C. sativa without nitrogen fertilizer, which can result in reduced nitrate
leaching (Hendrischke et al. 1998) and long-term nitrate pollution (Addiscott and Darby

69

1991).
When 90 kg P^Og/ha was added to the greenhouse soil in combination with, or in the
absence of a nitrogen fertilizer, plants possessed significantly greater heights, number of
internodes, intemode diameters, fresh weights and fresh/dry weight ratios compared to those
without phosphoms. Therefore, results of this study complement previous findings that 30100 kg PiOg/ha treatment increases stem yield (Ruzsanyi 1970, Ivonyi et al. 1997, BCMAF
2000). However, claims that on low phosphoms soils, the application of phosphoms fertilizer
alone results in decreased stem height and weight (Ruzsanyi 1970), and that C. sativa is
likely able to absorb the small quantity of phosphoms it needs from the soil (Ivonyi et al.
1997) were not supported. Unless the presence of phosphoms enabled the plants to maximize
the use of the low nitrogen available in the soil, the lack of nitrogen fertilizer effect on stem
morphology suggests that the claim that C. sativa requires phosphoms to aid in nitrogen-use
efficiency (Bocsa and Kams 1998) was also not supported.
The significant interaction effect between nitrogen fertilizer type and phosphoms
level on intemode fresh/dry weight ratio complements the phosphoms level effect, as all
treatments experienced an increased result with the application of phosphoms fertilizer. It can
be deduced from the interaction graph that inorganic nitrogen fertilizer treatment experienced
the greatest increase, and fishmeal the least. It must be noted that significant differences
within interaction effects were not statistically analysed.

5.2 Anatomy of Greenhouse-Grown C. sativa var. fédrina
Anatomical characteristics of greenhouse-grown C. sativa var. fédrina were affected
by nitrogen fertilizer type but not level. The ratios of primary phloem fibre/total fibre area
and volume were significantly higher for control plants compared to those of any type of
70

nitrogen fertilizer treatment. This implies that secondary tissue development (secondary
phloem and xylem) are neither enhanced nor inhibited by nitrogen application. Just as
phloem fibres function in plant mechanical support, the aggregation of the less flexible
secondary xylem fibres produced during secondary thickening of the stem supply vertical
strength (McDougall et al. 1993, Bocsa and Karus 1998). Although correlation analyses
between anatomical and morphological characteristics were not performed, the absence of a
positive nitrogen fertilizer effect on characteristics such as stem height, weight or diameter
coincides with the absence of a positive effect on secondary tissue development.
The results of the present study indicate that there are no significant differences
between those of the control and/or three levels of nitrogen fertilizer, and that some primary
phloem characteristics are even improved by the absence of nitrogen fertilizer, as suggested
by the fertilizer type results. This is in contrast to previous findings that treatments with 56 or
112 kg N/ha increase fibre yield (Jordan et al. 1946), and that 80 kg N/ha produces higher
bast contents than 200 kg N/ha treatment (Van der Werf et al. 1995a). Unless excess nitrogen
application would occur above the 300 kg N/ha treatment presently analysed, the claim that it
produces stems with thin phloem sections of low fibre quantity (Bocsa and Karus 1998) is
also unsupported.
The proportion of phloem fibre, and a high primary and low secondary phloem fibre
content in the stem, are principal quality parameters for the use of C. sativa in textile and
paper production (Meijer 1994, Van der Werf et al. 1994b, Bocsa and Karus 1998, Keller et
al. 2001, Mediavilla et al. 2001). Therefore, the lack of a significant nitrogen level effect and
the higher ratios of primary phloem fibre/total fibre area and volume for control plants
compared to those of any type of nitrogen fertilizer treatment, suggest that the absence of a
nitrogen fertilizer is advantageous for primary phloem fibre production and subsequently for
71

textiles and paper manufacturing. In addition to, and as with greenhouse plant morphology
characteristics, the absence of a difference in the effects of nitrogen fertilizer type suggest
that if fertilizer use occurred, organic fertilizer would produce outcomes comparable to those
of inorganic nitrogen fertilizer.
Anatomical characteristics of greenhouse-grown plants were affected by the
application of phosphorus. Primary phloem fibre area, secondary phloem fibre area and
volume, xylem area and volume, total fibre area and volume, primary phloem fibre cell wall
thickness, secondary phloem fibre/total fibre area and volume, xylem/total fibre area and
volume ratios were each significantly higher in treatments with 90 kg PzO^/ha application.
However, the number of primary phloem fibre cells/mm^, primary phloem fibre/total fibre
area and volume ratios, and total phloem fibre/total fibre area and volume ratios were
significantly higher in treatments without phosphorus addition. There is no apparent reason
for the inconsistent result of primary phloem fibre area, compared to other primary phloem
fibre results. Therefore, the absence of phosphorus fertilizer application is advantageous for
primary phloem fibre production, and secondary phloem fibre and xylem is enhanced by
phosphorus application. This improved secondary tissue development (secondary phloem and
xylem) corresponds with the positive effect of phosphorus on relevant morphological
characteristics such as stem height, weight and diameter.
As with the stem morphology, the lack of nitrogen fertilizer effect on stem anatomy
suggests that the claim that C. sativa requires phosphorus to aid in nitrogen-use efficiency
(Bocsa and Karus 1998) was not supported and that investigation into the effects of different
levels of phosphorus fertilizer on stem morphology would be required to determine if
phosphorus requirements are lower when nitrogen fertilizer is present (Ivonyi et al. 1997).
The significant interaction effect between nitrogen fertilizer type and phosphorus
72

level on primary phloem/total fibre area and volume ratios complemented both the nitrogen
fertilizer type and phosphorus level effects. Control treatment results were greater than all
other treatments, and all treatments experienced a decreased result with the application of
phosphorus fertilizer. From the interaction graphs, it can be noted that control and inorganic
nitrogen fertilizer treatments experienced greater decreases than fishmeal and sea star with
the application of phosphorus fertilizer.
In general, morphological and anatomical characteristics of greenhouse plants were
unaffected by nitrogen fertilizer type or level. Phosphorus application benefited plant
morphology, secondary phloem fibre and xylem production, but its absence benefited
primary phloem fibre content. Results from this greenhouse trial suggest that phosphorus is a
more limiting factor than nitrogen on C. sativa growth.

5.3 Morphology of Field-Grown C. sativa var. fédrina
In the field trial, nitrogen fertilizer type did not significantly affect plant morphology,
however, nitrogen level did. The lack of a nitrogen fertilizer type effect suggests that the use
of organic nitrogen fertilizer produces outcomes comparable to those of inorganic fertilizer
for C. sativa morphology.
Treatment with 150 kg N/ha resulted in significantly higher plant heights than the
other nitrogen levels, and the number of internodes and intemode diameters were positively
affected by addition of 150 or 300 kg N/ha. Further, fresh weights were significantly higher
for the 150 or 300 kg N/ha compared to the control. This confirms that nitrogen fertilization
affects stem height (Jordan et al. 1946, Van der Werf et al. 1995a), diameter (Jordan et al.
1946, Van der Werf et al. 1995a, Van der Werf and Van den Berg 1995, Scheifele 1999) and
number of nodes (Van der Werf and Van den Berg 1995).
73

Nitrogen levels assessed in this research are not equivalent to previous work, however
they are somewhat similar, and can be compared. In contrast to the present results for height,
previous studies have found that compared to 200 kg N/ha, treatment with 80 kg N/ha
increases stem height (Van der Werf et al. 1995a). If stem height is indeed correlated with
stem yield (Meijer and Keizer 1994), then the present results may lend support to previous
work which found that compared to 0 kg N/ha, stem yield increased with 113 (Ruzsanyi
1970) or 160 kg N/ha treatments (Ivonyi et al. 1997), and that stem yield increased between
100 and 160 kg N/ha treatment (Struik et al. 2000). Stem yield decrease between 160 and
240 kg N/ha treatments (Ivonyi et al. 1997) may be supported, while stem yield increase
between 160 and 220 kg N/ha treatments (Struik et al. 2000) is not.
The significant interaction effect between nitrogen fertilizer type and level on the
number of intemodes complemented that of the nitrogen fertilizer level effect, but offered
information beyond that of the nitrogen fertilizer type, where there was no effect. From the
interaction graph, it can be noted that control treatment results were lower than all other
treatments, and that 150 kg bloodmeal N/ha produced the highest, and 75 kg inorganic N/ha
the second highest, number of intemodes.
Both in conjunction with, and in the absence of nitrogen fertilizer application, plants
without phosphoms treatment had significantly greater heights, intemode diameters, fresh
and dry weights compared to plants treated with 90 kg P20s/ha. Therefore, claims that, on
low phosphoms soils, the application of phosphoms fertilizer alone results in decreased stem
height and weight (Ruzsanyi 1970), that 30-100 kg PiOg/ha treatment increases stem yield
(Ruzsanyi 1970, Ivonyi et al. 1997, BCMAF 2000) or that C. sativa requires phosphoms to
aid in nitrogen-use efficiency (Bocsa and Kams 1998) were not supported. However, the
suggestion that C. sativa plants are able to absorb the small quantity of phosphoms needed
74

from the soil (Ivonyi et al. 1997) could be warranted.

5.4 Anatomy of Field-Grown C. sativa var. fédrina
Nitrogen fertilizer type significantly affected three anatomical characteristics of field
plants. The area of primary phloem fibre was higher with fishmeal or inorganic nitrogen
fertilizer treatment and the volume of primary phloem fibre was highest in the control,
however, the effects were not differentiated by post-hoc analysis. Effects on total fibre
volume were differentiated through post-hoc tests, which noted control treatment total
volume was lower than that of either fishmeal or inorganic treatment. Similar treatment
effects on intemode length or fibre ratios did not exist and therefore cannot explain the
opposing treatment effects on primary phloem area and volume. Until otherwise determined,
it will be assumed that nitrogen fertilizer type presented only a minimal, and inconsequential,
effect on primary phloem production.
Nitrogen fertilizer level affected anatomical characteristics of field-grown plants.
Xylem area and volume, total fibre volume and xylem/total fibre area and volume ratios were
significantly higher with 150 and/or 300 kg N/ha treatment compared to the control. Primary
phloem fibre/total fibre area and volume ratios and total phloem fibre/total fibre area and
volume ratios were significantly higher for the control treatment plants. Therefore, primary
phloem fibre development is improved in the absence of, and xylem and total fibre
development are improved in the presence of, higher levels of nitrogen fertilizer. Although
correlation analyses between anatomical and morphological characteristics were not
performed, the increased height, diameter and number of internodes with the treatment of 150
or 300 kg N/ha coincides with the secondary tissue and total fibre development which would
be required to mechanically support such increases in morphology. From these results, it can
75

also be assumed that increased morphological growth does not equate to increased yield of
the more valuable primary phloem fibre component of the stem.
If total fibre yield is considered, the present results support previous work, which
found that nitrogen treatment increases fibre yield, although present levels of 150 or 300 kg
N/ha were higher than the 56 or 112 kg N/ha previously noted (Jordan et al. 1946). However,
work which found that 80 kg N/ha produces higher bast contents than 200 kg N/ha treatment
(Van der Werf et al. 1995a) was not supported by the present study, which found greater
primary and total phloem ratios with 0 kg N/ha treatment. If excess nitrogen is considered to
be that above 0 kg N/ha, then present counts of primary phloem fibre cell numbers did not
support the claim that excess nitrogen application produces stems with low bast fibre
quantity. However, the potential thinner phloem sections (Bocsa and Karus 1998) were
supported by the greater primary and total phloem ratios with 0 kg N/ha treatment.
The significant interaction effect between nitrogen fertilizer type and level on
secondary phloem area and volume offered information beyond that of the nitrogen fertilizer
type or nitrogen fertilizer level, which found no effect. From the interaction graph, it can be
noted that control treatment results were lower than all other treatments, and that 150 kg
fishmeal N/ha produced the highest results and 75 kg inorganic N/ha the second highest.
Anatomical characteristics in the field were affected by phosphorus level. Treatments
with the absence of phosphorus fertilizer produced greater primary phloem fibre areas, xylem
areas and volumes and total fibre areas and volumes. The number of primary phloem
fibres/mm^ was higher in treatments with the presence of 90 kg P20s/ha. These data suggest
that phosphorus has a minimal effect on primary phloem fibre. The positive effect of the
absence of phosphorus fertilizer on xylem and total fibre measurements corresponds with the
positive effect on relevant morphological characteristics such as height and diameter.
76

Therefore, claims that C. sativa requires phosphorus to aid in nitrogen-use efficiency (Bocsa
and Karus 1998) were not supported, but it may be true that C. sativa plants are able to
absorb the small quantity of phosphorus needed from the soil (Ivonyi et al. 1997).
To generalize, field morphological characteristics were unaffected by nitrogen
fertilizer type while any level, 150 and/or 300 kg N/ha in particular, exhibited positive
results. Fishmeal or inorganic nitrogen fertilizer and 150 and/or 300 kg N/ha levels benefited
some anatomical characteristics, however, primary phloem fibre results were greater in the
absence of nitrogen fertilizer. The absence of phosphorus fertilizer was beneficial for field
morphological and many anatomical characteristics. In contrast to the greenhouse trial
results, those from this field trial suggest that phosphorus is not a more limiting factor than
nitrogen on C. sativa growth.

5.5 Physiological Considerations
There has been limited research on the effects of plant growth regulators (PGRs) on

C. sativa fibre production (see literature review). However, documented studies on the effect
of PGRs on vascular development in other plants are available. It appears that auxin to
gibberellin ratio, and cytokinin level, are important for fibre differentiation and composition
within the stem (Atal 1961, Saks et al. 1984, Aloni 1979,1995). Results from the present
research suggest that the absence of fertilizer application is beneficial for primary phloem
fibre production. It is possible that the stem density used in this study to limit lateral growth,
and height variability, resulted in conditions which produced optimal PGR levels for desired
primary phloem fibre composition. Investigation into potential relationships between PGR
levels within the plant and nutrients such as nitrogen and phosphorus, are required to help
understand the underlying physiological mechanisms of fibre production in C. sativa.
77

5.6 Conclusions
1. Greenhouse-grown C. sativa y av. fédrina morphology, secondary phloem fibre and xylem
were positively affected by 90 kg PiOg/ha treatment. Phosphorus was a more limiting
factor than nitrogen on greenhouse-grown C. sativa var. fédrina.
2. Field-grown C. sativa var. fédrina morphology, secondary phloem fibre and xylem were
positively affected by 150 and/or 300 kg N/ha treatment of any nitrogen fertilizer type.
Nitrogen was a more limiting factor than phosphorus on field-grown C. sativa var.
fédrina.
3. Greenhouse and field-grown C. sativa yav. fédrina primary phloem fibre was positively
affected by the absence of nitrogen or phosphorus fertilizer application. This supports the
claim that C. sativa variety and plant density are the principal parameters to consider for
C. sativa bast fibre cultivation (Van der Werf et al. 1996).
4. Unless correlation analysis proves otherwise, improvements in morphological
characteristics should not be used to infer improved primary phloem fibre yields.

6 Future Research and Recommendations
This study has more data available for analysis. Within treatment variability on
morphology and anatomy characteristics would be beneficial as they may affect harvesting
and processing techniques. A high yield treatment with high variability may be less appealing
than one of low yield and low variability. More thorough analysis of interaction effects, and
correlation analysis within morphological and anatomical, and between morphological and
anatomical characteristics, would also be useful. The ability to use morphological
characteristics to reliably predict primary phloem fibre content would be an asset for fibre
cultivation.
78

Additional anatomical measurements could also be performed on intemode crosssectional images. These may include analysis of collenchyma tissue, whole fibre bundle
measurements, increased cells counts and cell diameters of both primary and secondary
phloem, xylem cell and non-fibre tissue measurements. Variation of primary phloem fibre
cell shape and lumen size, secondary xylem shape and wall thickness could also he assessed
and used for research on the impact of such characteristics on fibre quality.
In this study, both greenhouse and field soil phosphorus levels were low and
considered negligible, yet greenhouse phosphorus treatment results were in contrast to field
results. This strongly suggests that further investigation into phosphoms effects on,
requirements of, and potential soil microorganism associations with, C. sativa are warranted.
Similar research on potassium is also recommended. Findings of the present research suggest
that organic fertilizer is as effective as inorganic; therefore, research into potential organic
sources to meet all C. sativa nutrient requirements is also recommended.
Measurements not conducted in this study, but are highly recommended for future
work as they may offer additional insight into possible reasons for particular results include
those of plant growth regulators, soil temperature, plant sex, root characteristics and
mycorrhizal status, and self-thinning rates.
A study should be conducted with traditional wood chemistry, manual dissection
mass fraction techniques and cross-section techniques to see if results from the different
methodologies can be compared. Such studies may give alternate options for future C. sativa
fibre research techniques.
The literature review and study comparison of this thesis focused on C. sativa fibre
cultivation. As information directly relevant to this present work is very limited, and the
present results appear unique, investigation into fertilizer research on other fibre producing
79

plants is strongly recommended.
The high number of variables that influence C. sativa makes it successful as a highly
adaptable plant that can thrive in a multitude of conditions. The more one understands how
this species can grow and develop under different regimes, the greater the potential for its
serious use as a fibre-producing crop. Further, given that it exhibits a large variety of cell
types in addition to different morphological and reproductive characteristics, it has great
appeal for general botanical studies and as a plant example for laboratory instruction.

80

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Van der Werf, H.M.G., H.E. Harsveld van der Veen, A.T. M. Bouma and M. ten Cate.
1994b. Quality of hemp (Cannabis sativa L.) stems as a raw material for paper. Ind Crop
Prod 1: 203-210.
Van der Werf, H.M.G. and W. Van den Berg. 1995. Nitrogen fertilization and sex expression
affect size variability of fibre hemp (Cannabis sativa L.). Oecologia 103: 462-470.
Van der Werf, H.M.G., W.C.A. Van Geel, L.J.C. Van Gils and A.J. Haverkort. 1995a.
Nitrogen fertilization and row width affect self-thinning and productivity of fibre hemp
(Cannabis sativa L.). Field Crops Res 42: 27-37.

86

Van der Werf, H.M.G., W.C.A. Van Geel and M. Wijlhuizen. 1995b. Agronomic research on
hemp (Cannabis sativa L.) in the Netherlands, 1987-1993. J Int Hemp Assoc 2(1): 14-17.
Van der Werf, H.M.G., M. Wijlhuizen and J.A.A. de Schutter. 1995c. Plant density and self­
thinning affect yield and quality of fibre hemp (Cannabis sativa L.). Field Crops Res 40:
153-164
Van der Werf, H.M.G., E.W.J.M. Mathijssen and A.J. Haverkort. 1996. The potential of
hemp (Cannabis sativa L.) for sustainable fibre production: a crop physiological
appraisal. Ann Appl Biol 129:109-123.
Van der Werf, H.H.G. 1997. The effect of plant density on light interception in hemp
(Cannabis sativa L.). J Int Hemp Assoc 4(1): 8-13.
Van Roekel, G.J. 1994. Hemp pulp and paper production. J Int Hemp Assoc 1:12-14.
Van Roekel, G.J., S.J.J. Lips, R.G.M. Op den Kamp and G. Baron. 1995. Extrusion pulping
of tme hemp bast fibre (Cannabis sativa L.). TAPPI Proceedings, 1995 Conference 477485.
Vignon, M R., D. Dupeyre and C. Garcia-Jaldon. 1996. Morphological characterization of
steam-exploded hemp fibres and their utilization in polypropylene-bases eomposites.
Biosci Tech 58: 203-215.
Vignon, M R. and C. Garcia-Jaldon. 1996. Structural features of the peetic polysaceharides
isolated from retted hemp bast fibres. Carboh Res 296: 249-260.
Weiner, J. and S. C. Thomas. 1986. Size variability and eompetition in plant monocultures.
OIKOS 47: 211-222.

87

UNBC Greenhouse Environmental Conditions, 2000
24

"T 80

-70
22
■ 60
20
50 ®
-T em perature (°C)
-Daylength (hrs)
-Relative Humidity

30 3

■

N

o

CO

CO
CO

CO

18

S

CO

20

S

Growing Day Number

Appendix A. Temperature (°C), daylength (hrs) and relative humidity of the UNBC greenhouse during the 64 days of
Cannabis sativa ysx. fédrina cultivation, July 4 - September 5,2000.

88

Gitsegukla Field Environmental Conditions, 2000
29

24

19

ÏI
O a

-T em perature (°C)
- Daylengtti (Mrs)

14 -

- Precipitation (mm)

o

CO

to

a>
CO

s

to

s to

Growing Day Number

Appendix B. Temperature (°C), daylength (hrs) and precipitation (mm) of the Gitsegukla field during the 68 days of
Cannabis sativa \ar.fêdrina cultivation, July 6 - September 11,2000.

89

Appendix C
Randomized block ANOVA on the effects of fertilizer treatment on stem morphology of
Cannabis sativa yar.fédrina grown in the UNBC greenhouse.
Dependent Variable
Height (cm)

Source*
B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

df
3
2
2
1
4
2
2
4
57

SS
17313.675
134.580
659.485
5858.684
1367.532
549.166
372.844
711.637
17740.355

F
18.54
0.22
1.06
18.82
1.10
0.88
0.60
0.57

P
0.000
0.806
0.353
0.000
0.366
0.419
0.553
0.684

Number of intemodes

B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

3
2
2
1
4
2
2
4
57

19.371
1.171
2.544
24.976
2.115
0.741
0.100
5.523
49.043

7.50
0.68
1.48
29.03
0.61
0.43
0.06
1.60

0.000
0.510
0.237
0.000
0.654
0.652
0.944
0.186

* B, block; N, nitrogen fertilizer type; [N], nitrogen level; P, phosphorus
fertilizer.

90

Randomized block ANOVA on the effects of fertilizer treatment on third internode
length and diameter of Cannabis sativa xar.fédrina grown in the UNBC greenhouse.
Dependent Variable
Length (cm)

Source*
B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

df
SS
3 229.405
2
2.073
2
2.744
1
2.826
4
9^35
2
0.788
2
2.178
4
13.897
57 103.348

F
42.17
0.57
0.76
1.56
1.36
0.22
0.60
1.92

P
0.000
0.568
0.474
0.217
0.261
0.805
0.552
0.120

Diameter (mm)

B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

3
2
2
1
4
2
2
4
57

16.34
0.68
0.64
4632
1.60
0.34
0.07
0.87

0.000
0.509
0.529
0.000
0.188
0.715
0.935
0.488

16.713
0.466
0.439
15.797
2.179
0.231
0.046
1.186
19.438

* B, block; N, nitrogen fertilizer type; [N], nitrogen level; P, phosphorus
fertilizer.

91

Randomized block ANOVA on the effects of fertilizer treatment on third internode
weights of Cannabis sativa \ar.fédrina grown in the UNBC greenhouse.
Dependent Variable
Fresh weight (g)

Source* df
B
3
N
2
2
[N]
P
1
N[N]
4
NP
2
2
[N]P
N[N]P
4
Error
57

SS
3.724
0.019
0.065
0.746
0.208
0.138
0.016
0.203
2.546

F
27.79
0.21
0.73
16.70
1.16
1.54
0.18
1.14

P
0.000
0.812
0.487
0.000
0.337
0.223
0.839
0.349

Dry weight (g)

B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

3
2
2
1
4
2
2
4
57

0.033
0.008
0.002
0.008
0.016
0.010
0.000
0.029
0.229

273
1.02
0.30
2.02
1.00
1.26
0.06
1.80

0.052
0.368
0.741
0.161
0.413
0.291
0.940
0.141

Fresh/dry weight

B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

3 114.172
2
6.237
2
1.514
1 134.620
4 51.162
2 59.655
2
0.049
4 22.935
57 389.085

5.58
0.46
0.11
19.72
1.87
4.37
0.00
0.84

0.002
0.636
0.895
0.000
0.128
0.017
0.996
0.506

* B, block; N, nitrogen fertilizer type; [N], nitrogen level; P, phosphorus
fertilizer.

92

Randomized block ANOVA on the effects of fertilizer treatment on third internode
primary phloem fibre area and volume of Cannabis sativa yar.fédrina grown in the
UNBC greenhouse.
Dependent Variable*
PP area (mm^)

Sourcet
B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

df
3
2
2
1
4
2
2
4
57

SS
2.190
0.008
0.040
1.107
0.125
0.008
0.002
0.114
1.808

F
23.01
0.13
0.62
34.88
0.98
0.13
0.03
0.89

P
0.000
0.882
0.539
0.000
0.424
0.883
0.970
0.473

PP volume (mm^)

B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

3
2
2
1
4
2
2
4
57

23.131
0.251
0.021
0.133
0.259
0.019
0.148
1.279
8.939

49.16
0.80
0.07
0.85
0.41
0.06
0.47
2.04

0.000
0.455
0.937
0.361
0.798
0.942
0.627
0.101

* PP, primary phloem fibre
t B, block; N, nitrogen fertilizer type; [N], nitrogen level;
P, phosphorus fertilizer

93

Randomized block ANOVA on the effects of fertilizer treatment on third internode
secondary phloem fibre area and volume of Cannabis sativa yar.fédrina grown in the
UNBC greenhouse.
Dependent Variable*
SP area (mm^)

Sourcet df
B
3
N
2
2
[N]
P
1
N[N] 4
NP
2
2
[N]P
N[N]P 4
Error 57

F
0.67
1.77
0.43
90.80
1.32
1.62
0.10
2.06

P
0.571
0.180
0.651
0.000
0.272
0.207
0.909
0.098

SP volume (mm^)

B
1.54
3 1.597
N
2 0.803
1.16
2 0.210 0.30
[N]
P
1 16.478 47.74
N[N]
4 1.263 0.91
NP
1.67
2 1.155
[N]P
2 0.116 0.17
N[N]P 4 2.230
1.62
Error 57 19.673

0.213
0.320
0.739
0.000
0.462
0.197
0.845
0.183

SS
0.131
0.230
0.056
5.894
0.344
0.210
0.012
0.534
3.700

* SP, secondary phloem fibre
t B, block; N, nitrogen fertilizer type; [N], nitrogen level;
P, phosphorus fertilizer

94

Randomized block ANOVA on the effects of fertilizer treatment on third internode
xylem area and volume of Cannabis sativa ysLV.fédrina grown in the UNBC greenhouse.
Dependent Variable*
X area (mm"^)

Sourcet df
B
3
N
2
2
[N]
P
1
N[N] 4
NP
2
2
[N]P
N[N]P 4
Error 57

SS
0.673
0.308
0.232
6.058
0.541
0.156
0.056
0.332
6.039

F
2.12
1.45
1.10
57.18
1.28
0.73
0.26
0.78

P
0.108
0.242
0.341
0.000
0.290
0.484
0.769
0.541

X volume (mm^)

B
3
N
2
2
[N]
P
1
N[N] 4
NP
2
2
[N]P
N[N]P 4
Error 57

6.652 5.04
0.935
1.06
1.41
1.238
21.873 49.72
1.51
2.659
2.016 2.29
0.64
0.563
0.906 0.51
25.075

0.004
0.352
0.253
0.000
0.211
0.110
0.531
0.725

* X, xylem fibre
t B, block; N, nitrogen fertilizer type; [N], nitrogen level;
P, phosphorus fertilizer

95

Randomized block ANOVA on the effects of fertilizer treatment on third internode
total fibre area and volume of Cannabis sativa var.fedrina grown in the UNBC
greenhouse.
Dependent Variable*
T area (mm^)

Sourcet df
3
B
2
N
2
[N]
1
P
4
N[N]
2
NP
2
[N]P
4
N[N]P
57
Error

SS
6.439
1.188
0.813
35.293
2.404
0.790
0.103
1.923
27.178

F
4.50
1.25
0.85
74.02
1.26
0.83
0.11
1.01

P
0.007
0.295
0.432
0.000
0.296
0.442
0.897
0.411

T volume (mm^)

B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

3
2
2
1
4
2
2
4
57

73.347
1.389
2.707
82.827
5.546
5.412
1.147
5.439
93.686

14.88
0.42
0.82
50.39
0.84
1.65
0.35
0.83

0.000
0.657
0.444
0.000
0.503
0.202
0.707
0.513

* T, total fibre (PP+SP+X)
t B, block; N, nitrogen fertilizer type; [N], nitrogen level; P, phosphorus
fertilizer

96

Randomized block ANOVA on the effects of fertilizer treatment on third internode
primary phloem fibre cell count and wall thickness of Cannabis sativa var.fédrina
grown in the UNBC greenhouse.
Dependent Variable*
# PP/mm^

Sourcet df
B
3
N
2
2
[N]
P
1
N[N]
4
NP
2
[N]P
2
N[N]P 4
Error 57

PP cell wall thickness (mm)

B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

3
2
2
1
4
2
2
4
57

SS
10245103.728
396832.233
602100.979
17965245.269
2141088.089
307707.952
533986.096
2458545.817
20322961.821

F
9.58
0.56
0.84
50.39
1.50
0.43
0.75
1.72

P
0.000
0.576
0.435
0.000
0.214
0.652
0.478
0.157

0.0000265
0.0000005
0.0000002
0.0000072
0.0000012
0.0000010
0.0000000
0.0000019
0.0000255

19.71
0.55
0.20
16.14
0.66
1.08
0.03
1.04

0.000
0.578
(1823
0.000
0.620
0.345
0.971
0.392

* PP, primary phloem fibre
t B, block; N, nitrogen fertilizer type; [N], nitrogen level; P, phosphorus fertilizer

97

Randomized block ANOVA on the effects of fertilizer treatment on third internode
primary phloem fihre/total fibre area and volume ratio of Cannabis sativa var.fédrina
grown in the UNBC greenhouse.
Dependent Variable*
PP/T area

Sourcet df
B
3
N
2
2
[N]
P
1
N[N] 4
NP
2
2
[N]P
N[N]P 4
Error 57

SS
0.018
0.040
0.006
0.575
0.005
0.040
0.005
0.027
0.236

F
1.44
4.87
0.75
139.03
Œ33
4.86
0.61
1.65

P
0.241
0.011
0.475
0.000
0.858
0.011
0.548
0.175

PP/T volume

B
3
N
2
2
[N]
P
1
N[N] 4
NP
2
2
[N]P
N[N]P 4
Error 57

0.086
0.125
0.020
1.669
0.006
0.129
0.014
0.086
0.757

2.15
4.70
0.75
125.67
0.11
4.86
0.53
1.61

0.104
0.013
0.478
0.000
0.980
0.011
0.593
0.183

* PP, primary phloem fibre
t B, block; N, nitrogen fertilizer type; [N], nitrogen level;
P, pbospborus fertilizer

98

Randomized block ANOVA on the effects of fertilizer treatment on third internode
secondary phloem fibre/total fibre area and volume ratio of Cannabis sativa var.fédrina
grown in the UNBC greenhouse.
Dependent Variable*
SP/T area

Sourcet df
B
3
N
2
[N]
2
P
1
N[N] 4
NP
2
[N]P
2
N[N]P 4
Error 57

SS
0.010
0.019
0.001
0.371
0.014
0.020
0.006
0.026
0.192

F
0.98
280
0.13
110.15
1.02
3.00
0.91
1.90

P
0.407
0.069
0.879
0.000
0.406
0.058
0.409
0.122

SP/T volume

B
3
N
2
2
[N]
P
1
N[N]
4
NP
2
2
[N]P
N[N]P 4
Error 57

0.024
0.033
0.003
0.657
0.019
0.029
0.008
0.060
0.478

0.97
1.95
0.18
78.24
0.57
1.74
0.50
1.78

0.413
0.152
0.835
0.000
0.687
0.185
0.609
0.145

* SP, secondary phloem fibre;
t B, block; N, nitrogen fertilizer type; [N], nitrogen level;
P, pbospborus fertilizer

99

Randomized block ANOVA on the effects of fertilizer treatment on third internode
xylem/total fibre area and volume ratio of Cannabis sativa \ar.fédrina grown in the
UNBC greenhouse.
Dependent Variable*
X/T area

Sourcet df
B
3
2
N
2
[N]
P
1
N[N]
4
NP
2
2
[N]P
N[N]P 4
Error 57

SS
0.014
0.007
0.004
0.022
0.008
0.005
0.000
0.005
0.142

F
1.85
1.43
0.72
&93
0.80
1.08
0.03
0.48

P
0.148
0.247
0.489
0.004
0.530
0.347
0.975
0.750

X/T volume

B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

0.050
0.043
0.019
0.232
0.033
0.042
0.001
0.016
0.608

1.55
2.03
0.91
21.77
0.77
1.95
0.04
038

0.212
0.141
0.408
0.000
0.552
0.151
0.961
0.821

3
2
2
1
4
2
2
4
57

* X, xylem fibre
t B, block; N, nitrogen fertilizer type; [N], nitrogen level;
P, phosphorus fertilizer

100

Randomized block ANOVA on the effects of fertilizer treatment on third internode
total phloem fîhre/total Hhre area and volume ratio of Cannabis sativa \ar.fédrina
grown in the UNBC greenhouse.
Dependent Variable*
PP+SP/T area

Sourcet df
B
3
N
2
2
[N]
P
1
N[N]
4
NP
2
2
[N]P
N[N]P 4
Error 57

SS
0.014
0.007
0.004
0.022
0.008
0.005
0.000
0.005
0.142

F
1.85
1.43
0.72
8.93
0.80
1.08
0.03
0.48

P
0.148
0.247
0.489
0.004
0.530
0.347
0.975
0.750

PP+SP/T volume

B
3
2
N
[N]
2
P
1
N[N]
4
NP
2
2
[N]P
N[N]P 4
Error 57

0.050
0.043
0.019
0.232
0.033
0.042
0.001
0.016
0.608

1.55
2.03
0.91
21.77
0.77
1.95
0.04
0.38

0.212
0.141
0.408
0.000
0.552
0.151
0.961
0.821

* T, total fibre (PP+SP+X)
t B, block; N, nitrogen fertilizer type; [N], nitrogen level;
P, phosphorus fertilizer

101

Appendix D
Randomized block ANOVA on the effects of fertilizer treatment on stem morphology of
Cannabis sativa ywc.fédrina grown in the Gitsegukla Held.
Dependent Variable Source*
Height (cm)
B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

df
3
2
2
1
4
2
2
4
57

SS
34026.403
1077.711
5649.188
2167.502
1557.684
1005.270
347.015
1147.674
14106.640

F
46.12
2.19
11.49
8.81
1.58
2.04
0.71
1.17

P
0.000
0.121
0.000
0.004
0.191
0.139
0.498
0.335

B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

3
2
2
1
4
2
2
4
57

26.861
0.362
2.968
0.416
5.281
0.200
0.641
0.276
15.755

32.39
0.65
5.37
1.51
4.78
0.36
1.16
0.25

0.000
0.523
0.007
0.225
0.002
0.698
0.321
0.909

Number of internodes

* B, block; N, nitrogen fertilizer type; [N], nitrogen level;
P, phosphorus fertilizer.

102

Randomized block ANOVA on the effects of fertilizer treatment on third internode
length and diameter of Cannabis sativa yar.fédrina a grown in the Gitsegukla field.
Dependent Variable Source* df
Length (cm)
B
3
N
2
2
[N]
P
1
N[N]
4
NP
2
2
[N]P
N[N]P 4
Error 57

SS
138.562
16.064
8.236
5.650
14.979
11.139
10.152
11.488
252.308

F
10.43
1.81
0.93
1.28
0.85
1.26
1.15
0.65

P
0.000
0.172
0.400
0.263
0.502
0.292
0.325
0.630

3
2
2
1
4
2
2
4
57

24.409
1.957
:L839
2.364
:1533
(1867
0.053
1.299
22.388

20.71
2.49
3.61
6.02
1.61
1.10
0.07
0.83

0.000
0.092
0.033
0.017
0.184
0.338
0.935
0.513

Diameter (mm)

B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

* B, block; N, nitrogen fertilizer type; [N], nitrogen level;

103

Randomized block ANOVA on the effects of fertilizer treatment on third internode
weights of Cannabis sativa \ar.fédrina a grown in the Gitsegukla field.
Dependent Variable Source*
Fresh weight (g)
B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

df
SS
3 22.510
2
1.851
2 4.747
1 3.520
4
1.481
2
1.129
2 0.127
4
1.119
57 25.353

F
16.87
2.08
5.34
7.91
0.83
1.27
0.14
0.63

P
0.000
0.134
0.008
0.007
0.510
0.289
0.868
0.644

Dry weight (g)

B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

3
2
2
1
4
2
2
4
57

0.404
0.059
0.032
0.107
0.011
0.018
0.015
0.056
0.735

10.44
2.31
1.25
8.33
0.22
0.71
0.58
1.09

0.000
0.109
0.293
0.005
0.925
0.494
0.565
0.370

Fresh/dry weight

B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

3 82.319
2 28.798
2 41.147
1 34.195
4 36.620
2 61.441
2 33A88
4 19.822
57 808.151

1.94
1.02
1.45
2.41
0.65
2.17
1.17
0.35

0.134
0.369
0.243
0.126
0.632
0.124
0.318
0.843

* B, block; N, nitrogen fertilizer type; [N], nitrogen level;
P, phosphorus fertilizer.

104

Randomized block ANOVA on the effects of fertilizer treatment on third internode
primary phloem fibre area and volume of Cannabis sativa \a r. fédrina grown in the
Gitsegukla field.

Dependent Variable*
PP area (mm^)

Sourcet df
B
3
2
N
2
[N]
P
1
4
N[N]
2
NP
2
[N]P
N[N]P 4
Error 57

SS
4.059
0.352
0.282
0.330
0.353
0.060
0.080
0.099
2.753

F
28.02
3.64
2.92
6.84
1.83
0.62
0.82
0.51

P
0.000
0.033
0.062
0.011
0.136
0.543
0.444
0.725

PP volume (mm^)

B
3 31288
N
2 3.493
2 1.925
[N]
P
1 1.615
4 0.461
N[N]
NP
2 1.441
2 2.345
[N]P
N[N]P 4 2.235
Error 57 26.494

22.44
3.76
2.07
3.47
0.25
1.55
2.52
1.20

0.000
0.029
0.135
0.068
0.910
0.221
0.089
0.320

* PP, primary phloem fibre
t B, block; N, nitrogen fertilizer type; [N], nitrogen level;
P, pbospborus fertilizer

105

Randomized block ANOVA on the effects of fertilizer treatment on third internode
secondary phloem fibre area and volume of Cannabis sativa y sly. fédrina grown in the
Gitsegukla field.
Dependent Variable*
SP area (mm^)

Sourcet df
B
3
N
2
2
[N]
P
1
N[N]
4
NP
2
2
[N]P
N[N]P 4
Error 57

SS
0.993
0.109
0.163
0.138
0.674
0.133
0.073
0.067
3.357

F
5.62
0.93
E38
2.35
2.86
1.13
0.62
0.28

P
0.002
0.402
0.259
0.131
0.031
0.329
0.542
0.888

SP volume (mm^)

B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

1.880
0.292
0.286
0.270
1.622
0.143
0.112
0.294
7.805

4.58
1.07
1.05
1.97
2.96
0.52
0.41
0.54

0.006
0.351
0.358
0.166
0.027
0.595
0.666
0.709

3
2
2
1
4
2
2
4
57

* SP, secondary phloem fibre
t B, block; N, nitrogen fertilizer type; [N], nitrogen level;
P, pbospborus fertilizer

106

Randomized block ANOVA on the effects of fertilizer treatment on third internode
xylem area and volume of Cannabis sativa \a r. fédrina grown in the Gitsegukla field.
Dependent Variable*
X area (mm^)

Sourcet df
B
3
2
N
2
[N]
1
P
N[N] 4
NP
2
[N]P 2
N[N]P 4
Error 57

SS
5.976
0.571
1.222
1.055
1.571
0.488
0.080
0.329
10.432

F
10.88
1.56
3.34
5.76
2.15
1.33
0.22
0.45

P
0.000
0.219
0.043
0.020
0.087
0.272
0.805
0.772

X volume (mm^)

B
3 74.398
2
N
6.474
2 18.460
[N]
P
1 12.445
N[N] 4 12.343
2 5.121
NP
[N]P 2 0.106
N[N]P 4
7.140
Error
57 111.958

12.63
1.65
4.70
6.34
1.57
1.30
0.03
0.91

0.000
0.201
0.013
0.015
0.194
0.279
0.973
0.465

* X, xylem fibre
t B, block; N, nitrogen fertilizer type; [N], nitrogen level;
P, phosphorus fertilizer

107

Randomized block ANOVA on the effects of fertilizer treatment on third internode
total fibre area and volume of Cannabis sativa ystv. fédrina grown in the Gitsegukla
field.
Dependent Variable*
T area (mm^)

SS
Sourcet df
B
3 29.5421
N
2 2.79908
2 3.90051
[N]
P
1 3.89601
N[N]
4 6.97644
2 1.44663
NP
2 0.52834
[N]P
N[N]P 4 1.2448
Error 57 40.2082

F
13.96
1.98
2.76
5.52
2.47
1.03
0.37
0.44

P
0.000
0.147
0.071
0.022
0.055
0.365
0.689
0.778

T volume (mm^)

B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

19.98
3.00
4.24
7.05
1.63
1.12
0.28
1.30

0.000
0.058
0.019
0.010
0.179
0.334
0.754
0.282

3
2
2
1
4
2
2
4
57

240.307
24.019
34.006
28.283
26.173
8.954
2272
20.800
228.517

* T, total fibre (PP+SP+X)
t B, block; N, nitrogen fertilizer type; [N], nitrogen level;
P, phosphorus fertilizer

108

Randomized block ANOVA on the effects of fertilizer treatment on third internode
primary phloem fibre cell count and wall thickness of Cannabis sativa \a r. fédrina
grown in the Gitsegukla Held.
Dependent Variable*
# PP/mm^

F
SS
Sourcet df
B
3 5718589.417 22.16
N
2 261274.089
1.52
2 217761.028
1.27
[N]
P
1 451337.577 5.25
N[N]
4 788397.421 2.29
NP
2
0.57
97680.498
2
69591.534
0.40
[N]P
N[N]P
4 338101.938 0.98
Error
57 4902944.923

P
0.000
0228
0.290
0.026
0.071
0.570
0.669
0.424

PP cell wall thickness (mm)

B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

0.000
0.172
0.837
0.305
0.255
0.308
0.499
0.702

3
2
2
1
4
2
2
4
57

0.0000236
0.0000024
0.0000002
0.0000007
0.0000036
0.0000016
0.0000009
0.0000014
0.0000375

11.95
1.81
0.18
1.07
1.37
1.20
0.70
0.55

* PP, primary phloem fibre
t B, block; N, nitrogen fertilizer type; [N], nitrogen level; P, phosphorus
fertilizer

109

Randomized block ANOVA on the effects of fertilizer treatment on third internode
primary phloem fîbre/total fibre area and volume ratio of Cannabis sativa yar. fédrina
grown in the Gitsegukla field.

Dependent Variable* Sourcet
PP/T area
B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error
PP/T volume

B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

SS
0.012
0.000
0.024
0.003
0.014
0.008
0.005
0.004
0.199

F
1.11
0.06
3.36
0.95
1.02
1.10
0.68
0.26

P
0.352
0.940
0.042
0.335
0.403
0.339
0.513
0.902

3 0.023
2 0.000
2 0.082
1 0.012
4 0.037
2 0.019
2 0.024
4 0.006
57 0.515

0.85
0.01
4.52
1.27
1.03
1.08
1.31
0.18

0.473
0.993
0.015
0.264
0.399
0.348
0.279
0.949

df
3
2
2
1
4
2
2
4
57

* PP, primary phloem fibre
t B, block; N, nitrogen fertilizer type; [N], nitrogen level;
P, phosphorus fertilizer

110

Randomized block ANOVA on the effects of fertilizer treatment on third internode
secondary phloem fîhre/total fîhre area and volume ratio of Cannabis sativa ysa^.fédrina
grown in the Gitsegukla fîeld.
Dependent Variable* Sourcet df
SS
SP/T area
B
3 0.003
N
2 0.000
2 0.001
[N]
P
1 0.000
N[N]
4 0.012
NP
2 0.002
2 0.003
[N]P
N[N]P 4 0.003
Error 57 0.100

F
0.56
0.08
0.42
0.10
1.66
0.54
0.73
0.42

P
0.642
0.921
0.656
0.750
0.172
0.584
0.484
0.790

SP/T volume

0.27
0.15
0.09
0.07
1.82
0.26
0.80
1.00

0.848
0.864
0.916
0.796
0.138
0.768
0.455
0.417

B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

3
2
2
1
4
2
2
4
57

0.001
0.000
0.000
0.000
0.010
0.001
0.002
0.005
0.076

* SP, secondary phloem fibre
t B, block; N, nitrogen fertilizer type; [N], nitrogen level;
P, phosphorus fertilizer

111

Randomized block ANOVA on the effects of fertilizer treatment on third internode
xylem/total fibre area and volume ratio of Cannabis sativa y ax. fédrina grown in the
Gitsegukla Held.
Dependent Variable* Sourcet
X/T area
B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

df
3
2
2
1
4
2
2
4
57

SS
0.004
0.001
0.014
0.002
0.004
0.002
0.003
0.000
0.058

F
1.43
0.37
7.01
1.90
0.99
1.16
1.56
0.09

P
0.243
0.689
0.002
0.174
0.423
0.319
0.219
0.984

X/T volume

3
2
2
1
4
2
2
4
57

0.025
0.000
0.073
0.010
0.025
0.015
0.021
0.001
0.307

1.53
0.04
6.78
1.77
1.15
1.35
1.94
0.03

0.218
0.965
0.002
0.188
0.343
0.267
0.153
0.998

B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

* X, xylem fibre
t B, block; N, nitrogen fertilizer type; [N], nitrogen level;
P, phosphorus fertilizer

112

Randomized block ANOVA on the effects of fertilizer treatment on third internode
total phloem fihre/total fibre area and volume ratio of Cannabis sativa \a r. fédrina
grown in the Gitsegukla field.
Dependent Variable
PP+SP/T area

Sourcet
B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

df
3
2
2
1
4
2
2
4
57

SS
0.004
0.001
0.014
0.002
0.004
0.002
0.003
0.000
0.058

F
1.43
0.37
7.01
1.90
0.99
1.16
1.56
0.09

P
0.243
0.689
0.002
0.174
0.423
0.319
0.219
0.984

PP+SP/T volume

B
N
[N]
P
N[N]
NP
[N]P
N[N]P
Error

3
2
2
1
4
2
2
4
57

0.025
0.000
0.073
0.010
0.025
0.015
0.021
0.001
0.307

1.53
0.04
6.78
1.77
1.15
1.35
1.94
0.03

0.218
0.965
0.002
0.188
0.343
0.267
0.153
0.998

* T, total fibre (PP+SP+X)
t B, block; N, nitrogen fertilizer type; [N], nitrogen level;
P, phosphorus fertilizer

113