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REPUBLIC OF RWANDA
MINISTRY OF EDUCATION
HIGHER INSTITUTE OF AGRICULTURE AND ANIMAL
HUSBANDRY (ISAE)
FACULTY OF AGRICULTURE AND RURAL
DEVELOPMENT
Presented by:
Donatien NIYIBIGIRA
For the Partial Fulfillment of the
requirement of the award of
Bachelor’s Degree in Horticulture
Research Supervisor:
Mr. NG’ETICH (MSc.)
Academic year: 2011
Effect of Organic and Inorganic Fertilizer on Growth and
Yield of Collards (Brassica oleracea var. acephala).
A case study of Musanze Rwanda.
i
DEDICATION
To:
Almighty God;
My family;
My beloved parents;
My brothers and sisters;
My friends and classmates;
I dedicate this memoir to them.
ii
DECLARATION
I, Donatien NIYIBIGIRA declare that this Memoir is an original research work supervised
by Mr. Onesmus NG’ETICH, and has not been published earlier in any other higher
institution. This memoir has been submitted for the partial fulfillment of the requirement
of the award of Bachelor’s Degree (Ao) In Horticulture at the Higher Institute of
Agriculture and Animal Husbandry (ISAE).
Student name:
Donatien NIYIBIGIRA:………………… Signature:….………………………
Date: …………………
Supervisor:
Mr. Onesmus NG’ETICH:………………. Signature..………………….……..
Date: …………………
iii
ACKNOWLEGDEMENTS
First and foremost, I thank the Almighty God for His abundant blessings, guidance and
protection during my studies in ISAE. I acknowledge the contributions of many scientists
which have been cited in this dissertation for detailed general information, and regret any
inadvertent omission. I deeply acknowledge the Government of Rwanda for offering the
second cycle in ISAE. I am also thankful to ISAE authorities for providing all necessary
facilities during the research work.
I acknowledge all the academic staff, especially the lecturers of the department of Crop
Production for their kind assistance in both theoretical and practical knowledge provided.
I highly feel indebted and full of gratitude to the Higher Institute of Agriculture and
Animal Husbandry especially to the lecturers in the Faculty of Agriculture and Rural
Development for the training they offered to me.
It is great pleasure for me to express my great sense of gratitude to my supervisor, Mr.
Onesmus NG’ETICH, for his valuable suggestions, constructive criticism and painstaking
efforts throughout the period of project work.
From the bottom of my heart, I would like to acknowledge my family and the family of
Mulindabigwi Desire for the moral support, advices, encouragements, love, joy and
sympathy expressed during this research.
I am thankful to my brothers, sisters, friends and classmates for their moral support during
the course of my study.
Finally any other who, near or far, feel have contributed to our intellectual development
and the achievement of this work, here are our heartfelt thanks.
Donatien NIYIBIGIRA
iv
ABSTRACT
Appropriate soil fertility is essential for increased and sustainable crop production.
However mineral fertilizers are expensive. An alternative way of overcoming the
problems of declining soil fertility is to use an integrated fertilization. As a result, an
experiment was carried out to find suitable fertilizer regime which could give an economic
yield of collard (Brassica oleracea var. acephala). This experiment was arranged in a
Randomized Complete Block Design with three replicates. Treatments were as following:
(T1): the control without any fertilizer, (T2): the combination of 150 kg/ha of N: P: K (17-
17-17) and 10 t/ha of Farmyard manure, (T3): 20 t/ha of farmyard manure alone and (T4):
300 kg/ha of N: P: K (17-17-17). These were applied as basal application of fertilizer in
this experiment. The parameters studied were; plant height, stem diameter and leaf area,
fresh yield, dry biomass yield, pH, Nitrogen, Phosphorus, Potassium and organic carbon.
The results of this study revealed that there were significant differences in plant height,
stem diameter and leaf area during the early stage of the growth and later. Higher yields of
223.0 t/ha was obtained from the plants subjected to the combination of both farmyard
manure and N: P: K (17-17-17) whereas the control gave the lowest yield (104.7 t/ha).
From this study, it could be stated that the combination of farmyard manure and N:P:K
(17-17-17) at the rate of 10 t/ha of farmyard manure and 150 kg/ha of N:P:K gives higher
yield (223.0 t/ha) and this combination could possibly reduce the cost of production in the
cultivation of collard. From the results, the leaf area from plants treated with 150 kg/ha of
N: P: K (17-17-17) and farmyard manure (10 t/ha) was significantly higher by 76%
compared to the control. The chemical soil analysis after the experimental period showed
that there was an increased of Nitrogen by 8.6%, Phosphorus by 43.8%, Potassium by
32.0% organic carbon by 7.4%, organic matter by 0.65% while there was a reduction of
pH and C/N ratio by 0.54% and 10.5% respectively for the treatment subjected to 150
kg/ha of N: P: K (17-17-17) and farmyard manure (10 t/ha). Therefore through the highest
yield obtained by use of the combination of both organic and inorganic fertilizer, we
recommend to the farmers the application of mineral fertilizers in combination of
Farmyard manure for maximizing collards production and at the same time improving the
physical, chemical and biological properties of the soil.
RESUME
v
La fertilité du sol appropriée est très importante pour l’augmentation et la production
végétale durable. Cependant, les engrais minéraux sont très chers. Un moyen alternatif de
dépasser les problèmes de baisse de fertilité du sol est d’utiliser la fertilisation intégrée.
C’est pourquoi une expérimentation a été conduite pour identifier lequel convenable
fertilisant qui pourrait donner un rendement économique de chou précoce (Brassica
oleracea var. acephala). Le dispositif expérimental est celui de blocs aléatoires
complètement randomisées avec trois répétitions qui étaient les suivants: (T1) : le témoin,
(T2) : la combinaison de 150 kg/ha de N:P:K (17-17-17) and 10 t/ha de fumure organique,
(T3) :20 t/ha de fumure organique seule et (T4) :300 kg/ha de N:P:K (17-17-17). Ceux-ci
ont été appliqués comme étant des fertilisants de base. Les Paramètres étudiés étaient : la
hauteur de plante, diamètre de la tige, surface de la feuille, le rendement frais des feuilles,
le rendement sec des biomasses, pH du sol, Azote, Phosphore, Potassium, et Carbone
organique. Les résultats de cette étude ont révélé qu’il y’ avait les différences
significatives dans les hauteurs de plantes, diamètre de la tige et surface du feuille durant
la croissance la plus jeune de la plante. Le plus haut rendement de (223.0 t/ha) a été obtenu
des plantes soumises à la combinaison de 150 kg/ha de N:P:K (17-17-17) et 10 t/ha de
fumure organique au moment où le témoin donnait le plus petit rendement (104.7 t/ha). De
cette étude on peut dire que la combinaison de fumure organique et N:P:K (17-17-17) a
donné un rendement profitable de (223.9 t/ha) et cette combinaison pourrait réduire le coût
de production dans la culture de chou précoce. De ces résultats, la surface des feuilles de
plantes traitées par 150kg /ha of N : P : K (17-17-17) et la fumure organique (10 t/ha)
étaient significativement grand par 76%par rapport au control. Les analyses chimique du
sol après l’expérience ont montré qu’il avait une augmentation d’azote 8.6%, phosphore
par43.8%, potassium par 32.0%, carbone organique par 7.4%, matière organique par
0.65% alors qu’il y avait une réduction du pH and le rapport de carbone et azote par 0.54%
et 10.5% respectivement pour les traitements traités par 150kg /ha of N : P : K (17-17-17)
et la fumure organique (10 t/ha). Cependant, de ce plus haut rendement obtenu de la
combinaison de la fumure organique et inorganique, nous recommandons aux agriculteurs
d’utiliser la combinaison de la fumure organique et inorganique pour maximiser la
production de choux précoces et d’améliorer à même temps les propriétés physique,
chimique et biologique du sol.
vi
vii
TABLE OF CONTENTS
DEDICATION .......................................................................................................................i
DECLARATION ..................................................................................................................ii
ACKNOWLEGDEMENTS .................................................................................................iii
ABSTRACT.........................................................................................................................iv
RESUME .............................................................................................................................iv
TABLE OF CONTENTS....................................................................................................vii
LIST OF TABLES ................................................................................................................x
LIST OF FIGURES .............................................................................................................xi
LIST OF APPENDICES.....................................................................................................xii
ACRONYMS AND ABREVIATIONS.............................................................................xiv
CHAPTER ONE ...................................................................................................................1
INTRODUCTION ................................................................................................................1
1.1 Background Information ...................................................................................................... 1
1.2. Problem Statement............................................................................................................... 2
1.3.1. General objective ................................................................................................ 2
1.3.2. Specific objectives .............................................................................................. 2
1.4. Hypotheses .......................................................................................................................... 3
CHAPTER TWO ..................................................................................................................4
REVIEW OF LITERATURE ...............................................................................................4
2.1. Overview of Collards .......................................................................................................... 4
2.1.1. Origin and Botanical Description ....................................................................... 4
2.1.2. Ecological requirement....................................................................................... 5
2.1.2. Horticultural production field practices.............................................................. 5
2.1.3. Nutritional value of collard................................................................................. 8
2.1.4. Role and Potential of Collard Green in Health Promotion ................................. 9
2.2. Effect of Fertilizers on Leafy Vegetables............................................................................ 9
2.2.1. Major or Macro-Nutrients .................................................................................. 9
viii
2.2.2. Functions of Macronutrients in Leafy Vegetables.............................................. 9
2.3. Effect of combine application of organic and inorganic fertilizer on leafy vegetable.......10
2.4. Time and Method of Fertilizer Application.......................................................................11
2.5. Composition of Farmyard manure.....................................................................................11
2.6. Fertilizer recommendations on collards, kales, cabbage and other related fodder crops. .12
CHAPTER THREE.............................................................................................................14
MATERIAL AND METHODS ..........................................................................................14
3.1. The experimental site ........................................................................................................14
3.2. Experimental Design and Treatment Application .............................................................15
3.3. Planting Materials..............................................................................................................16
3.4. Soil and Manure Nutrient Analysis ...................................................................................16
3.5. Mineral fertilizer (N: P: K 17-17-17) ................................................................................16
3.6. Other materials ..................................................................................................................16
3.7 Nursery bed preparation and sowing ..................................................................................17
3.8. Land Preparation and Treatment application.....................................................................17
3.9 Transplanting ......................................................................................................................17
3.10 Routine Management Practices ........................................................................................18
3.11. Data Collection ..................................................................................................18
3.11.1. Soil Sampling .................................................................................................18
3.11.2. Agronomic Parameters Measured ..................................................................19
3.11.3. Statistical Analysis .........................................................................................19
CHAPTER FOUR...............................................................................................................21
PRESENTATION AND INTERPRETATION OF RESULTS..........................................21
4.1. Effects of organic and inorganic fertilizers on soil chemical properties after transplanting
of collards..........................................................................................................................21
4.2. Effects of organic and inorganic fertilizers on plant height of Collard (cm).....................22
4.3. Effects of organic and inorganic fertilizers on number of leaves of Collard .....................23
4.4. Effects of organic and inorganic fertilizers on stem diameter (mm) of Collard ................24
4.5. Effects of organic and inorganic fertilizers on leaf area (cm2) of Collard.........................24
4.6 Effects of organic and inorganic fertilizers on Fresh weight (grams/plant) of Collard ......25
4.7 Effects of organic and inorganic fertilizers on oven-dry mass of edible leaves of Collard 26
ix
4.8 Effects of organic and inorganic fertilizers on Total fresh weight and Total oven-dry mass
of Collard ..........................................................................................................................27
CHAPTER FIVE.................................................................................................................13
DISCUSSION .....................................................................................................................13
5.1. Effects of organic and inorganic fertilizers on soil chemical properties after transplanting
of collards..........................................................................................................................13
5.2. Effects of organic and inorganic fertilizers on plant height of Collard in cm ...................15
5.3. Effects of organic and inorganic fertilizers on number of leaves of Collard.....................15
5.4. Effects of organic and inorganic fertilizers on stem diameter of Collard..........................16
5.5. Effects of organic and inorganic fertilizers on leaf area of Collard ..................................17
5.6. Effects of organic and inorganic fertilizers on Fresh and oven-dry mass of edible leaves of
Collard...............................................................................................................................17
5.7. Effects of organic and inorganic fertilizers on Total fresh weight and Total oven-dry mass
of Collard ..........................................................................................................................18
CHAPTER SIX ...................................................................................................................19
CONCLUSION AND RECOMMENDATIONS................................................................19
6.1 Conclusion ..........................................................................................................................19
6.2 Recommendations ..............................................................................................................20
REFERENCES. ........................................................................................................................21
APPENDICES ....................................................................................................................25
x
LIST OF TABLES
Table 1: Comparison of nutritional value between Collard and Cabbage ............................8
Table 2. The climatic data during the experimentation.......................................................14
Table 3: Effects of organic and inorganic fertilizers on soil chemical properties after
transplanting of Collard .......................................................................................22
Table 4: Effects of organic and inorganic fertilizers on plant height of Collard ................23
Table 5: Effects of organic and inorganic fertilizers on stem diameter (mm) of Collard ...24
Table 6: Effects of organic and inorganic fertilizers on Fresh edible yield of Collard.......26
Table 7: Effects of organic and inorganic fertilizers on oven-dry mass of edible leaves of
Collard..................................................................................................................27
xi
LIST OF FIGURES
Figure 1: Experimental layout.............................................................................................15
Figure 2: Sampling points in experimental plot. .................................................................18
Figure 3: Effects of organic and inorganic fertilizers on number of leaves of Collard after
15th and 25th day .................................................................................................23
Figure 4: Effects of organic and inorganic fertilizers on leaf area (cm2) of Collard ..........25
Figure 5: Effects of organic and inorganic fertilizers on total fresh weight and total oven-
dry mass of Collard (in grams). ..........................................................................13
Figure 6: Effects of organic and inorganic fertilizers on total fresh weight and total oven-
dry mass of Collard(T/ha)...................................................................................13
xii
LIST OF APPENDICES
Appendix 1:1Soil pH after harvesting after trial.................................................................25
Appendix 2: Nitrogen rate after harvesting (%)..................................................................25
Appendix 3: Phosphorus rate after harvesting (ppm) .........................................................26
Appendix 4: Potassium rate after harvesting (meq/100g)...................................................26
Appendix 5: Organic carbon after transplanting .................................................................27
Appendix 6: Organic matter after harvesting......................................................................27
Appendix 7: C/N ration.......................................................................................................28
Appendix 8: Effect of treatment on soil chemical ..............................................................13
Appendix 9: Interpretation norms of pH.............................................................................13
Appendix 10: Interpretation norms of O.M and available P, and total N ...........................13
Appendix 11: Number of leaves at 15th day after transplanting .........................................14
Appendix 12: Number of Leaves at 25th days after transplanting.......................................15
Appendix 13: Leaf area at 25th day after transplanting.......................................................15
Appendix 14: Plant height at 15th day after transplanting...................................................16
Appendix 15: Plant height at 25th day after transplanting (in cm) ......................................16
Appendix 16: plant height at 32th day after transplanting(cm) ...........................................16
Appendix 17: Plant height at the 39th day after transplanting (cm) ....................................17
Appendix 18: Plant height at the 46th day after transplanting.............................................17
Appendix 19: plant height at the 53rd day after transplanting (cm) ....................................17
Appendix 20: Stem diameter at 15th day after transplanting(mm)......................................18
Appendix 21: Stem diameter at 25th after transplanting (mm)............................................18
Appendix 22: Stem diameter at 32th after transplanting(mm).............................................18
Appendix 23: Stem diameter at 39th day after transplanting (mm).....................................19
Appendix 24 Stem diameter at 46th day after transplanting (mm) ......................................19
Appendix 25: Stem diameter at the 53rd day after transplanting (mm)...............................19
Appendix 26: Analysis of Variance of soil pH ...................................................................20
xiii
Appendix 27: Analysis of Variance of Total Nitrogen .......................................................20
Appendix 28: Analysis of Variance of available phosphorus .............................................20
Appendix 29: Analysis of Variance of available potassium ...............................................20
Appendix 30: Analysis of Variance of organic matter........................................................20
Appendix 31: Analysis of Variance of plant height at the 15th day ....................................21
Appendix 32: Analysis of Variance of plant height at the 25th day ....................................21
Appendix 33: Analysis of Variance of plant height at the 32nd day....................................21
Appendix 34: Analysis of Variance of plant height at the 39th day ....................................21
Appendix 35: Analysis of Variance of plant height at the 46th day ...................................21
Appendix 36: Analysis of Variance of plant height at the 53rd day....................................22
Appendix 37: Analysis of Variance of number of leaves at the 15th day............................22
Appendix 38: Analysis of Variance of number of leaves at the 25th day............................22
Appendix 39: Analysis of Variance of stem diameter at the 15th day.................................22
Appendix 40: Analysis of Variance of stem diameter at the 25th day.................................22
Appendix 41: Analysis of Variance of stem diameter at the 32nd day................................23
Appendix 42: Analysis of Variance of stem diameter at the 35th day.................................23
Appendix 43: Analysis of Variance of stem diameter at the 46th day.................................23
Appendix 44: Analysis of Variance of stem diameter at the 53rd day ................................23
Appendix 45: Analysis of Variance of leaf area .................................................................23
Appendix 46: Analysis of Variance of fresh weight at the 25th day ...................................24
Appendix 47: Analysis of Variance of fresh weight at the 39th day ...................................24
Appendix 48: Analysis of Variance of fresh weight at the 53rd day ...................................24
Appendix 49: Analysis of Variance of total fresh weight in t/ha........................................24
Appendix 50: Analysis of Variance of total fresh weight in grams/ha ...............................24
Appendix 51: Analysis of Variance of Total oven-dry mass in grams/ha ..........................25
Appendix 52: Analysis of Variance of Total oven-dry mass in tones/ha ...........................25
Appendix 53: Picture in the field from the beginning up to the end of the experiment......25
xiv
ACRONYMS AND ABREVIATIONS
ANOVA: -Analysis of Variance
C/N: -Carbon-Nitrogen ratio
FAO: -Food and Agriculture Organization
FYM: -Farm Yard Manure
GDP: -Gross Domestic Product
HSD: -Honestly Significant Difference
ISAE: -Institut Supérieur d’Agriculture et d’Elevage.
LA : -Leaf Area
MINAGRI: -Ministry of Agriculture and Animal Resources
MINALOC: -Ministry of Local government
N:P:K: -Nitrogen, Phosphate, Kalium (Potassium)
pH: -potential in Hydrogen
RCBD: -Randomized Complete Bloc Design
RHODA: -Rwanda Horticulture Development Agency
T/ha: -tons per hectare
Ttt: -Treatment
USA: -United States of America
USD: -United States Doll
1
CHAPTER ONE
INTRODUCTION
1.1 Background Information
The agricultural sector, remains at the center of Rwanda’s development and is now
recognized as the engine of growth that will drive poverty reduction in Rwanda and
improve the livelihood of its population (MINAGRI, 2007). Shifting cultivation, as
practiced by the traditional farmers to restore soil fertility in sustaining cropping can no
longer meet up with the increased need for food supply due to high population pressure.
The length of fallow period required to replenish the soil to maintain soil productivity has
to be shortened. The primary function of soil productivity and fertility restoration through
fallow is less effective since intensive cropping is now more common. The use of
inorganic fertilizers alone has not been helpful under intensive agriculture because it
aggravates soil degradation (Sharma and Mittra, 1991).
The degradation is brought about by loss of organic matter which consequently results in
soil acidity, nutrient imbalance and low crop yields. Any effort in crop production is
achieved through increasing productivity rather than expansion of production area. The
maximum productivity would be achieved through a combination of proper use of
improved agricultural techniques including fertilization. (MINAGRI, 2008).
Response of crops to applied fertilizer depends on soil organic matter. The quantity of soil
organic matter depends on the quantity of organic material which can be introduced into
the soil either by natural returns through roots, stubbles, sloughed-off root nodules and
root exudates or by artificial application in the form of organic manure which can
otherwise be called organic fertilizer (Agboola and Omueti, 1982).
The need to use renewable forms of energy has revived the use of organic fertilizers
worldwide. Nutrients contained in organic manures are released more slowly and are
stored for a longer time in the soil, thereby ensuring a long residual effect (Sharma and
Mittra, 1991). Improvement of environmental conditions and public health as well as the
need to reduce costs of fertilizing crops are also important reasons for advocating
increased use of organic materials (Seifritz, 1982). Application of organic manures also
improves the soil microbial properties (Belay et. al., 2001)
2
The benefits derivable from the use of organic materials is however not fully used in
Musanze .
Therefore, the present study was carried out to study the response of vegetative growth
and yield of the collard Brassica oleracea var. acephala, to applied organic manures
compared with mineral fertilization
1.2. Problem Statement
Rwanda is among countries in Sub-Saharan African and is experiencing high food
shortages. However, soil fertility is declining at alarming rate due to the limited use of
organic and mineral fertilizers, depletion of soil nutrients by continued cropping without
the use of fertilizers, soil erosion and farmers are unable to acquire fertilizers due to the
escalating market prices limiting its usage. The fore mention factors have led to continued
food shortages in the country. There are different ways to overcome the declining trends
in soil fertility including proper utilization of fertilizers which should provide part of
solution to plant requirement. Therefore, more emphasis is to be placed on technologies
and strategies to integrated use of both minerals and organic fertilizers. This is what
prompted me to conduct the study on effect of organic and inorganic fertilizers and the
combination of both on growth and yield of collard.
1.3.1. General objective
The main objective of the study is to evaluate the effect of organic and inorganic fertilizers
on growth and yield of collards (Brassica oleracea var. acephala)
1.3.2. Specific objectives
The specific objectives of the research study were:
1) To determine the effect of organic fertilizer (Farmyard manure) and inorganicfertilizers N:P:K (17-17-17) on growth and yield of collards.
2) To determine the effect of combined application of inorganic (N:P:K 17-17-17) andorganic fertilizer (Farmyard manure) on growth and yield of collards.
3
1.4. Hypotheses
To achieve the objectives, the following hypotheses were formulated:
1) Ho: There is no effect of organic fertilizer (Farmyard manure) and inorganic
fertilizers (N:P:K 17-17-17) on growth and yield of collards.
2) Ho: There is no effect of combined application of inorganic (N:P:K 17-17-17) and
organic fertilizer (Farmyard manure) on growth and yield of collards.
4
CHAPTER TWO
REVIEW OF LITERATURE
2.1. Overview of Collards
2.1.1. Origin and Botanical Description
The collard is a cool season crop that should be grown during early spring or fall. The
mature plant will withstand frosts and light to medium freezes. It is a cultivar of cabbage
(Brassica oleracea or Wild cabbage), and a member of the cabbage family (Brassica),
which is a genus of plants in the mustard family (Brassicaceae). Most people just refer to
them all as Cole crops or cabbages. Brassica plays a major role in the human diet (Sally,
2007). Like kale, cauliflower and broccoli, collards are descendents of the wild cabbage, a
plant thought to have been consumed as food since prehistoric times and have originated
in Asia Minor. From there it spread into Europe, being introduced by groups of Celtic
wanderers around 600 B.C. Collards have been cultivated since the times of the ancient
Greek and Roman civilizations. Collard greens dates back to the rate 17 th century in
United States (Fowke et al., 2006).
Collard greens are various loose-leafed cultivars of Brassica oleracea (Acephala Group),
the same species that produces cabbage and broccoli. The plant is grown for its large,
dark-colored, edible leaves. They are classified in the same cultivar group as kale and
spring greens, to which they are closely similar genetically. The name collard is a
shortened form of the word colewort "cabbage plant" (Sally, 2007).
The Cultivar Group name Acephala ("without a head" in Greek) refers to the fact that this
variety of Brassica oleracea does not have the usual close-knit core of leaves like
cabbage. The plant is a biennial where winter frost occurs, perennial in even colder
regions. It is also moderately sensitive to salinity. It has an upright stalk, often growing up
to two feet tall. The plant is very similar to kale. Plant Varieties, Carolina Improved
Heading (or Morris), Georgia Southern, Blue Max, or Heavy crop. These varieties have
consistently done well in North Carolina conditions. Popular cultivars of collard greens
include Georgia Southern, Morris Heading, Butter Collard (Korus , 2009).
5
2.1.2. Ecological requirement
Collards may be grown in a variety of soils. Heavier loamy soils will produce the greatest
yields. The lighter, well drained, sandy soils are best for early spring crops. Soils should
be well drained, rich in organic matter and have a pH of 6.0 to 6.5 (University of minisota,
2009) Leafy vegetables require quick, continuous growth for best quality. They need
ample nitrogen for good green color and tender growth. For average soils use 600 pounds
of 10-10-10 (or equivalent) fertilizer per acre (8 pints per 100 feet of row) before planting.
Side dress with 15 to 30 pounds of nitrogen per 3 to 5 weeks after the seed comes up or
after transplanting, and 2 to 3 weeks after that, (Delahaut, 1997). Collard is extremely
resistant to warm as well as cool temperature. Collards require full sun, and although they
can withstand more drought than the cabbage, (Sally, 2007).
2.1.2. Horticultural production field practices
a) Cropping Systems
There are four general ways to produce collards: Grow plants and set transplants in early
spring, and harvest the whole plant 50 to 60 days later. Grow plants and transplant in early
spring, and market cropped leaves in late spring, and carry plants over to fall when the
entire plant is harvested. Seed direct about August 15, or transplant from September 1 to
15, and harvest in late October to December. Seed direct to field in spring. These may be
harvested as leafy greens or thinned to 15 to 18 inches and carried over to fall. It requires
about 1 1/2 pounds of seed per acre (Sorensen, 1996).
b) Growing Plants and nursery arrangement
Plants may be grown by seeding directly in the field (1 to 2 pounds seed per acre) or in
protected beds (1 pound of seed per 1000 square feet). This should produce about 50 to 60
thousand plants or enough for about 4 to 5 acres. About 6 to 8 weeks will be required to
produce plants ready for transplanting (Sorensen, 1996).
6
c) Direct seeding
There are several good precision seeders on the market. In general, the seeders reduce seed
use by 40 to 70%. The stands are much more uniform and require very little thinning.
Uniform stands are easier to grow and harvest, thus reducing the cost of production.
Uniform stands grow evenly and are better weed competitors. Precision seeds that can be
used with collards include StanHay (belt type), Gaspardo and StanHay (vacuum type), and
Nibex (spoon type). Direct seeding can also be done with a Planet Jr., but requires more
seed and more thinning than stands established with precision seeders. Seed should be
placed in moist soil usually 1/2 to 3/4 inch deep, but never deeper than 1 inch. If adequate
moisture for germination is below 3/4 inch, irrigation should be applied. Frequent
irrigation is also important in obtaining good stands in hot weather (1/4 inch per day at
midday) (Delahaut, 1997).
d) Spacing
Spacing depends on how the crop will be produced. If the plants are to be cut when half
grown, they may be spaced 10 to 15 inches (25.4cm-38.1cm) apart. If they are to be
harvested when full grown they should be spaced 15 to 18 inches apart. If the seed is to be
drilled in the row and the young collard plants are to be harvested, similar to mustard
greens, the plants may be 2 to 4 inches apart. Rows should be 36 to 42 inches apart for
conventional systems. However, multi-row beds of 2 to 4 rows on 38 to 60 centers provide
greater yields and improved quality. In such a system, rows on each bed are spaced 12 to
18 inches apart. This provides rapid ground cover, fewer weeds and more tender growth.
(Delahaut, 1997)
e) Irrigation
Collards, like other members of this plant family, require above average moisture. Use
irrigation liberally in times of moisture stress, usually 1.5 inches per week when
precipitation is less than this. (Delahaut, 1997)
7
f) Weed management
The production method you use and the season you plant the crop will determine the kind
and extent of your weed problems. Chemical herbicides are available for use on collards
and are generally recommended. Whether you use an herbicide or not, some cultivation
will likely be necessary. Avoid deep cultivation. Close spacing and rapid growth will help
to suppress weeds (Delahaut, 1997).
g) Insect Management
Several worms (imported Cabbage worm, Cabbage looper, Diamond-back larvae) and
Harlequin bugs are the predominate insects. A rigid control program will be necessary,
especially during summer and fall. Aphids are also a serious problem during cool weather.
Use high pressure (200 psi) sprayers and a sticker to provide best control (Delahaut,
1997).
h) Disease Management
Some diseases like black rot are seed borne. You should insist on western grown,
chemically treated seed to reduce this disease. Another major disease is Downy Mildew
which produces discolored spots on the leaves. The Carolina variety has resistance to one
or more strains of Downy Mildew (Delahaut, 1997).
i) Harvesting
Harvesting may be done through: Cutting entire plants when very young, similar to
mustard greens (spaced 2 to 4 inches apart). Successive cutting can be done with these
systems. Cutting entire plants when about half grown (spaced 10 to 15 inches apart). And
they are tied in bunches of one to three plants with a rubber band, twisted or string;
Cutting entire plants when full grown (spaced 15 to 18 inches apart); Harvesting tender
leaves from full grown plants. When marketed these leaves are tied in one or two-pound
bunches. Check with your buyer to see how they would like the product packaged. Local
sales can often be made in bulk, but distant shipments and supermarket sales will have to
be placed in crates or cartons. Icing will also be necessary for quality maintenance
(Delahaut, 1997).
8
k) Cultivation and storage
The plant is commercially cultivated for its thick, slightly bitter edible leaves. They are
available year-round, but are tastier and more nutritious in the cold months, after the first
frost. For best texture, the leaves should be picked before they reach their maximum size,
at which stage the leaves will be thicker and should be cooked differently from the new
leaves. Age will not affect flavor. Flavor and texture also depend on the cultivar. Fresh
collard leaves can be stored for up to 10 days if refrigerated to just above freezing (1 °C)
at high humidity (>95%). In domestic refrigerators, fresh collard leaves can be stored for
about three days. Once cooked, they can be frozen and stored for greater lengths of time
(Delahaut, 1997).
2.1.3. Nutritional value of collard
Collard has mustard oil, sulphur and nitrogen containing compounds popular in fighting
Cancer. Their nutritional values exceed that of other known green vegetables. For
example; 100grams of collard contain; 85% water, 45calories energy and various minerals
such as 4.8grams, proteins 0.8grams fat, 7.5g carbohydrates, 250g calcium, 82mg
phosphorous, 1.5g iron, 43mg potassium, 9.300IU vitamin A, 0.16mg Thiamine, 0.31g
Riboflavin, 1.7mg Niacin and 1.52mg ascorbic acid (Lorenz & Maynard, 1980).
Table 1: Comparison of nutritional value between Collard and Cabbage
Nutritional value per
100 g of fresh yield
Collard greens
Nutritional value per 100 g of
fresh yield Cabbage,
Energy 151 kJ (36 kcal) 103 kJ (25 kcal)
Carbohydrates 7.1 g 5.8g
Fat 0.4 g 0.1g
Protein 3 g 1.28g
Vitamin A equiv. 575 μg (64%) 53μg (13%)
Vitamin C 26 mg (43%) 36.6mg (44%)
Vitamin K 623 μg (593%) 76(72%)
Calcium 210 mg (21%) 40mg (4%)
Source: USDA Nutrient database
9
2.1.4. Role and Potential of Collard Green in Health Promotion
Collards green are known to have a high cholesterol-lowering ability than all other
cruciferous vegetables such as: steamed kale, mustard green, broccoli, Brussels sprouts,
and cabbage in terms of its ability to bind bile acids in the digestive tract. When this bile
acid binding takes place, it is easier for the bile acids to be excreted from the body. Since
bile acids are made from cholesterol, the net impact of this bile acid binding is a lowering
of the body’s cholesterol level. It’s worth noting that steamed collards show much greater
bile acid binding ability than raw collards. We get unique health benefits from collard
greens in form of cancer protection. The cancer-preventive properties of collard greens
may be largely related to 4 specific glucosinolates found in this cruciferous vegetable:
glucoraphanin, sinigrin, gluconasturtiian, and glucotropaeolin. Each of these
glucosinolates can be converted into an isothiocyanate (ITC) that helps lower our cancer
risk by supporting our detox and anti-inflammatory systems (Ambrosone, 2009).
2.2. Effect of Fertilizers on Leafy Vegetables
2.2.1. Major or Macro-Nutrients
This group includes N, P and K which are required in maximum quantities by the plants.
These nutrients are often deficient in almost all the soils because of their heavy depletion.
The deficiency is corrected by the application of fertilizers based on soil analysis and crop
requirement (Rayar, 2004).
2.2.2. Functions of Macronutrients in Leafy Vegetables
a) Nitrogen
According to (Miller and Donahue 1990), Nitrogen is most often the limiting nutrient in
plant growth; it is a constituent of chlorophyll; plant proteins and nucleic acid. Nitrogen
can be utilized by plants as the ammonium cation or as the nitrate anion. It is then
involved in photosynthesis that is why an adequate supply of N is associated with high
photosynthetic activity, vigorous vegetative growth, and a dark green color. Excessive use
of Nitrogen in relation to other nutrients can delay crop maturity. Excess of Nitrogen can
lower the moisture content of grains at harvest, and causes weakening of cotton fiber and
cereal. (Amkha and Kazuyuki, 2006.)
10
b) Phosphorus
Phosphorus (P) does not occur as abundantly in soils as N and K. total concentration in
surface soils varies between about 0.02% and 0.10% .Unfortunately, the quantity of total P
in soils has little or no relationship to the availability of P to plants. P is the second most
often limiting nutrient. It is contained in plant cell nucleic and is part of energy storage and
transfer chemicals in the plants soils have low total and low plant-available phosphate
supplies because mineral phosphate forms are not readily soluble. P used by plants is taken
up as HPO42- and H2PO4
- anion. Unfortunately most soluble phosphates become fixed
(precipitated-form insoluble compound) before plants can absorb them. Organic
phosphates are important even major phosphate source in most soils (Miller and Donahue,
1990)
c) Potassium (K)
Potassium is one of essential nutrients required for plant growth and reproduction. It is
classified as a macronutrient as Nitrogen and phosphorus. It plays a vital role in
photosynthesis, carbohydrates transport, protein formation, control of ionic balance,
regulation of plant stomata and water use activation of plant enzymes and many other
processes (Munson et al., 1985)
d) Farmyard Manure (FYM)
Manure consists of animal excrement, usually mixed with straw or leaves. The amount and
quality of the excrement depend on the animals and feed. Good manure contains more
than just excrement and urine. According to FAO (1987), organic matter plays the
following roles: Improving soil structure; water infiltration and water retention; Improving
soil aeration and reduce the risk of erosion; in addition the organic matter has a buffer
effect that influences the variation of soil pH; Increasing the reserve of nutrients and
activating substances such as growth hormones; ( Parr and Hornic, 1995).
2.3. Effect of combine application of organic and inorganic fertilizer on leafyvegetable
Soil organic matter is the major reservoir of N and many other essential plant nutrients. It
is the main source of energy for soil organisms both plants and animals. The release of
Nitrogen from soil organic matter is controlled by soil micro-organisms.
11
During the decomposition of organic matter, soil microorganisms convert organic nitrogen
into ammonium (NH4+) and nitrate (NO3
-) forms of nitrogen which plants utilize. Its
combination with mineral fertilizer may increase vegetative growth. (Engel et al., 2001)
Organic manure supplies some nutrients for plants and the carbon containing compounds
are food for small animals and micro-organisms. Manures often improve the structure of
soils; they may do this directly through their action as bulky diluents in compacted soils or
indirectly when the waste products of animals or microorganism cement soil particles
together. These structural improvements increase the amounts of water useful to crops that
soil can hold, they also improve aeration and drainage and encourage good root growth by
providing enough pores of the right sizes and preventing the soil. (Cooke. 1967).
2.4. Time and Method of Fertilizer Application
Nitrogenous fertilizers must be applied in split, so that the Nitrogen loss through leaching
and washing could be reduced as Nitrogen being readily soluble and highly mobile is
subjected to these losses very easily. Therefore to achieve the highest recovery and
maximum use efficiency, it is essential that half of the total quality of the required
Nitrogen should be applied as basal and rest half in 2-3 split doses. Except in acidic and
highly alkaline soils, the Phosphorus must be applied in one dose as basal placement but in
acidic soils rock phosphate, bone meal or basic slay may be applied at least a fort right
before sowing or crop planting whereas in alkaline soils spraying of phosphate has given
better results.
The potassic fertilizers should be applied in single dose as basal placed but split
application along with N as top dressing has given better response in heavy soil types.
Sandy soil need split application of N for reduced loss of N through leaching. A
combination of organic manure and fertilizers is always beneficial for achieving highest
recovery and best fertilizer use efficiency (Miller and Donahue, 1990)
2.5. Composition of Farmyard manure
On average dry Farmyard manure contain about 2%N, 1.7% K and 0.4%P; but different
batches may contain very different percentages of nutrients depending on the origin and
storage. (Berryman, 1965)
12
2.6. Fertilizer recommendations on collards, kales, cabbage and other related foddercrops.
Practically in all experiments, collard, kales and cabbage responded well to nitrogen and at
least 50 kg N/ha are justified. It does not matter whether the N fertilizer is applied at
transplanting or a later top dressing, 50 kg of P2O2 and 50 kg of K2O are also
recommended respectively per hectare. There is little information on the Phosphorus and
potassium fertilization of these crops grown on average land, but they contain considerable
amounts of both P and K and these plant foods should be applied as fertilizers before
transplanting. Thus 300 kg/ha of N: P: K 17-17-17 compound fertilizer without farmyard
and 150 kg of N: P: K 17-17-17 with farmyard is respectively used assuming that 20t/ha of
farmyard manure only is used per hectare. (Cooke, 1972)
14
CHAPTER THREE
MATERIAL AND METHODS
3.1. The experimental site
This study was conducted at crop production research and demonstration field, ISAE Busogo,
Northern Province, Rwanda. The altitude of this region is 2200m above sea level and receives
four seasons well established throughout the year. Such seasons are: Short rainy season: It
covers the period between September and December; Short dry season: Starts around mid-
December and lasts till February; long rainy season: It covers the period ranging from March
to June; long dry season: It starts from June to September. (MINALOC, 2006). This region is
known to have annual rainfall of 1400 mm, with an average temperature of 13oC and relative
humidity of 86%
Table 2. The Climatic Data during the Experimentation
Months AverageTo
(oC)
Max.To( oC) Min.To (oC) Rainfall
(mm)
Humidity %
June 15.2 21.0 10.0 78.3 84
July 15.0 21.8 8.3 28.5 78
August 15.3 20.7 10.7 107.4 81
September 15.3 21.8 10.4 228.3 88
October 15.7 20.8 10.5 167.6 87
Source: ISAE station, 2011.
Busogo soil is permeable and generally it is fertile (MINALOC, 2006). The soil is of
volcanic type and is classified into Andisol. According Raymond, (1990) Andisols are
formed from volcanic ejecta (ash), characterized by loose and well aerated physical status.
The results of soils analysis of the experimental plots have shown that the soil could be
classified into fairly (weak) acidic soil. The average pH value recorded before trial was 5.83
and after trial, it was found to be 5.79. This area was chosen due to the fact that the area is
composed of organic soils which are fertile and where the vegetables are mostly grown
specially Brassicaceae.
15
3.2. Experimental Design and Treatment Application
The experimental design was randomized complete block design (RCBD) with 4 treatments
and each replicated three times. Total plots: 4 x 3=12 plots. Plot size was 1.5 m x1.5 m=2.25
m2. Thus the experimental field was 2.25 m2x12= 27 m2. As shown in the figure below, the
plots were separated with the paths of 0.5 m, between replications and 0.5 m between
treatments. Thus the total plots of experiment were 41.25 m2 and 1 m of borders was provided
around the experiment field on which cabbages were grown. The following treatments were
applied: Treatment 1: control; Treatment 2: 10 t/ha of FYM +150 kg /ha of N: P: K (17-17-
17); Treatment 3: 20 t/ha of FYM only; Treatment 4: 300 kg of N: P: K (17-17-17)/ha. Using
this rate, I based on the recommendation reported by (Cooke, 1972) and (Gupta, 1990).on
vegetables in the same family.
Figure 1: Experimental layout
T1 T3 T4 T2Block1
T3 T4 T2 T1
T4 T2 T1 T3
Block2
Block3
1.50 m
0.50 m
0.50m
1.50
m
16
Key:
T1 ═ Control;
T2 ═ 150 kg/ha of N: P: K 17-17-17 + 10t/ha of FYM;
T3 ═ 20t/ha of FYM;
T4 ═ 300 kg/ha of N: P: K 17-17-17
3.3. Planting Materials
The plant to be used was collards (Brassica oleracea var. acephala) of Brassicaceae family,
known to be highly adapted and productive in the similar conditions. The choice of this
vegetable was due to its nutrient value; adaptability and short vegetative cycle.
3.4. Soil and Manure Nutrient Analysis
The farm yard manure (FMY) used in this experiment was obtained from ISAE farm.
Farmyard manure content was 1.5% nitrogen, 0.44% of phosphorus and 1.25% of potassium.
The Farmyard which was used is 20 t/ha reported to 4.5 kg /plot of 2.25 m2 has been applied.
3.5. Mineral fertilizer (N: P: K 17-17-17)
The mineral fertilizer used is N:P:K 17-17-17, a mixed fertilizer which contains 17 kg of
nitrogen, 17kg of phosphorus and 17 kg of potassium in 100 kg of total compound. It is an
important mixed fertilizer for plants and vegetables growth in general and it is available in the
market (MINAGRI, 2010). In addition, the rate of 300 Kg/ha of N: P: K equivalent to 67.5 g
/2.25 m2 has been respectively applied.
3.6. Other materials
To carry out cultural farming practices like tillage; sowing, transplanting, weeding, and the
data collection, the following materials were used: hoe for cultivation, graduated ruler for
taking height and leave size measurements, electric weighing sensitive balance to measure the
weight of fertilizers and yield, the diameter to measure the size of plots, the stake to limit the
plot, rope bags and baskets to transport the farmyard manures, micrometric screw gauge to
measure stem diameter, oven to dry the harvested leaves. Leaf area for collards was taken
once at the 25thday after transplanting and it was determined, using the following formula:
green collard leaf area = (Length x Width) (0.67) as it was reported by Pearcy et al. 1989.
17
Leaf length was measured using a tape measure, beginning at the leaf blade-petiole intercept
to the leaf tip. The width was measured at the widest leaf lobes. Leaf length and leaf width
measurements were taken from a randomly selected 5th- leaf from the shoot tip.
3.7 Nursery bed preparation and sowing
Before I start my research, nursery bed preparation and sowing was done. The nursery was
prepared at 13th July 2011 by removing plant residues, breaking bigger soil particles. At the
same Certified seeds of collards bought from AGROTECH and were raised in the nursery 1
month before transplanting and watered once a day until the seedlings were ready to be
transplanted
3.8. Land Preparation and Treatment application
The land was ploughed by breaking the soil to achieve favorable tilth. The primary was done
on 13th July 2011 by removing plant residues, breaking bigger soil particles and taking needed
dimension. The second tillage was done on 12th August 2011 for making the soil suitable for
seed germination. Land plotting was carried out by respective plot size; this was followed by
labeling plot using pieces of wooden plank. After the soil unit was determined, the soil
samples were collected from the soil unit. This soil sample would be representative of that
soil unit. According to Dilip (1996): Soil is a heterogeneous body, so, if sample is collected
from only one spots of the soil unit, it would not represent it. To have the representative
value, the samples should be collected from several spots of the soil unit. Farmyard manure
with 20 t/ha and 10 t/ha from ISAE-farm was applied before transplanting in respective plots
(as shown on the design of experiment) and mixed with the soil using hand hoe. The mineral
fertilizers (N: P: K 17-17-17) with 150 kg/ha and 300 kg/ha were respectively applied in
treatment two and in treatment four at the time of transplanting. In some plots organic matter
and mineral fertilizer were applied separately while in others, they were combined
respectively with 10 t/ha of farm yard manure and 150kg/ha of N:P:K to evaluate their effect
on growth and yield of collards at the end of experiment.
3.9 Transplanting
After seedlings were ready to be transplanted, they were approached and healthy seedlings
were selected among others to be transplanted in rows spaced with 37cm and 37 cm between
(37 cm x 37cm). The seedlings were put into the holes made within the lines at the rates of 1
18
seedling per holes. Thus 16 Plants per plot. This means 16 x 12= 192 plants in the whole
experiment
3.10 Routine Management Practices
a. Weeding and Crop protection
Weeding control was done two times during the research time in 3rd and 6th weeks after
transplanting by using hands in order to allow water infiltration and aeration to the soil and
eventually keep the plants from weeds competition and make the field always clean. During
the young stage of the plant, insecticide “dethane” was used to control cut worms (Agrotis
Segitum).
3.11. Data Collection
3.11.1. Soil Sampling
Soil testing was known for a long time as one of the possible means for the determination of
fertilizer application rates. The logic behind this approach is that a soil contains enough
amounts of nutrients from a fertilizer application that can be reduced or increased. The need
for using soil tasting data for the determination of fertilizer application rates has become more
necessary. The continued uses of heavy doses of fertilizers have resulted in a high
accumulation of plant nutrients, particularly phosphate and potassium (Zulkifli et al., 1994).
Soil sampling was taken carefully in each plot before and after experiment at the 30 cm deep
top soil on plot basis. Five locations were selected in each plot. The equal portion of soil from
these 5 samples in each plot were taken and mixed for making a composite sample of 0.5 kg
that were representative for each plot. The composite samples were used in analysis for each
treatment.
The number of samples was one before field experiments and twelve after field experiment
which were analyzed in ISAE laboratory.
Figure 2: Sampling points in experimental plot.
* *
*
* **
19
Before laboratory analysis, the collected samples were air dried and then sieved with 2x 0.5
mm diameter sieve in soil laboratory of ISAE. The following chemical analysis was carried
out: Concentration of total nitrogen using KJELDHAL method, available phosphorus by
DICKNAN- BRAY method, available potassium using Cobalinitry method and the pH of soil
using pH meter.
3.11.2. Agronomic Parameters Measured
The parameters which were measured include:
Height of plants, this was recorded at the 15th day after transplanting and later during each
harvesting within interval of 7 days, it means respectively at 25th day, 32nd day, 39th , 46th day
and 53rd day after transplanting. To take the plant height, a ruler was used; the height was
taken from the soil level up to the youngest leave of plant.
Number of leaves was taken once at the 25th day by accounting each leaf from the bottom to
the top. Leaf area was another parameter to be recorded, this was recorded using also a
graduated ruler to take a leaf length and a leaf width then later leaf area was calculated using a
formula reported by Pearcy et al. 1989
Weight of fresh leaves was recorded at each harvesting. As harvesting was progressive at least
the three leaves were left to allow photosynthesis to remaining plant after fresh weight of
edible leaves were taken using electric weighing sensitive balance. Weight of oven-dry mass
of edible leaves was taken after drying the harvested leaves at 105oC for 10 hours.
Stem diameter was taken six times from the 15th day after transplanting up to the last
harvesting in order to evaluate the plant growth. To record this parameter a micrometric screw
gauge was used.
3.11.3. Statistical Analysis
The data collected were arranged in Microsoft excel and later subjected to analysis of
variance using JMP 5.1 computer software The treatments with significant means were
separated using Turkey HSD method for pair use comparison.
20
21
CHAPTER FOUR
PRESENTATION AND INTERPRETATION OF RESULTS
4.1. Effects of organic and inorganic fertilizers on soil chemical properties after
transplanting of collards
The observation gathered during laboratory experiments for determination of soil chemicals
properties are given in the appendix 8and the following table 3 indicates the means of soil
chemical observed after the experiment according to the applied treatments in the experimental
design. This shows also the effect of fertilizers on soil pH; Nitrogen; Phosphorus; Potassium;
Carbon; Organic Matter; and Carbon Nitrogen ratio after transplanting of Collard.
The single sample before the trial was taken by taking the four representative samples in four
corners of the field and one sample in the middle. These were mixed to have one representative
sample before transplanting. The results of pH-water observed, were 5.83 before experiment and
after harvesting, it was ranging from 5.76 to 5.82 and they were not significantly different each
other. The high mean was 5.8 and the highest value was observed in treatment subjected to the
combination of N: P: K and farmyard and treatment treated with farmyard only. The lowest
value was observed in the control. The concentration of total nitrogen in the soil of the
experiment site after harvesting was not significantly different with the high mean of 0.30%.
The value of available phosphorus before transplanting was of the average of 29.92 ppm. The
values of available phosphorus after harvesting were significantly different at p≤ 0.05 with the
range of 54.1 ppm to 22.1 ppm. The high mean was observed in treatment treated with farmyard
manure followed by the treatment subjected to the combination of N: P: K and farmyard. The
low mean was observed respectively in the control and treatment subjected to N: P: K, which
was not significantly different, each other. The treatments subjected respectively to N:P:K and
Farmyard were significantly higher in potassium content with high mean of 1.14meq/100g and
low means were in treatments treated with N:P:K and Farmyard with the low mean of 0.34
meq/100g. The potassium value before transplanting was 0.78 meq/100g.
The soil organic carbon concentration was 2.7% before transplanting and after harvesting, the
high mean of 2.9 % was observed in treatment with Farmyard manure.
Other treatments were not significantly different at p≤ 0.05 with the low mean observed in
treatment subjected to N: P: K (17-17-17). The effect of fertilizers on organic matter has shown
22
significant difference in all treatments with the high mean of 5% in treatment with Farmyard
manure while the exception was observed in treatment subjected to N:P:K application. The
average before transplanting was of 4.65% there. However, there was no significant difference
observed in carbon nitrogen ratio. The average value before transplanting was 11%
Table 3: Effects of organic and inorganic fertilizers on soil chemical properties aftertransplanting of Collard
pH Nitroge
n (%)
Phosphorus
(ppm)
Potassium
(meq)
Carbon
(%)
organic
matter(%)
C/N ratio
(%)
Control 5.76a 0.21a 22.1c 0.42bc 2.5ab 4.3ab3 12.4a
N:P:K
& FYM
5.8a 0.28a 43.7b 1.03a 2.7ab 4.7ab 10.5a
FYM 5.8a 0.30a 54.1a 1.14a 2.9a 5.0a 9.6a
N:P:K 5.79a 0.26a 30.3c 0.97ab 2.4b 4.2b 10.0a
*Means followed by the same letters are not significantly different according to Turkey HSD
at P ≤ 0.05
4.2. Effects of organic and inorganic fertilizers on plant height of Collard (cm)
The effect of different fertilizers on plant height varied with time. At 15 day after transplanting,
the plants which was treated with N:P:K was significantly taller with the mean height of 14.6 cm
at p≤ 0.05 while those subjected to farmyard manure alone and the combination of farmyard
manure and N:P:K followed with identical mean of 12.0 cm and 12.3 cm respectively upon
analysis. However, plants treated with farmyard manure and the control was not significantly
different at p≤ 0.05. In addition, it was observed that plants treated with N: P: K was
significantly higher by 40% compared with the control. The plants subjected to N: P: K,
farmyard manure and combination of both farmyard manure and N: P: K was not significantly
different from each other except the control at 25th and 32nd day after transplanting.
However, at 39th day after transplanting, the plants that were treated with N: P: K and the
combination of N: P: K and farmyard manure were significantly higher by about 31.5%
compared with the control at p≤ 0.05. The plants that were subjected to N: P: K, farmyard
23
manure and combination of both farmyard manure and N: P: K was the same in mean plant
height except for the control which significantly lower at 46th and 53rd day after planting.
Table 4: Effects of organic and inorganic fertilizers on plant height of Collard
15th day 25th day 32nd day 39th days 46th day 53rd day
Control 10.4c* 14.2b 18.0b 19.1c 20.0b 21.6b
N:P:K and FYM 12.3b 17.5ab 21.3ab 23.3ab 25.1a 27.8a
FYM 12.0bc 16.53ab 20.0ab 21.3bc 24.4a 27.7a
N:P:K 14.6a 21.0a 24.0a 25.1a 26.3a 29.0a
*Means followed by the same letters are not significantly different according to Turkey HSD
at P ≤ 0.05.
4.3. Effects of organic and inorganic fertilizers on number of leaves of Collard
The number of leaves has been recorded twice. The first record was done at the 15 th day after
transplanting and the second at the 25th day to determine the effect of organic and inorganic
fertilizers on their number during the plant growth (Appendix 11; 12; 37 and 38) and the
following Figure 3 shows that there was no significant difference between treatments
according to Turkey HSD at P ≤ 0.05.
a* a a a
10.1a a aa
0
5
10
15
Control NPK&FYM FYM NPK
Pla
nt h
eigh
t (cm
)
Treatments
15th day25th day
Figure 3: Effects of organic and inorganic fertilizers on number of leaves of Collardafter 15th and 25th day
24
4.4. Effects of organic and inorganic fertilizers on stem diameter (mm) of Collard
The means comparison of stem diameter of collard showed that the effects of organic and
inorganic fertilizers on stem diameter were not significantly different in all treatments from
the 15th, 25th day up to 32nd day after transplanting at p ≤ 0.05. The exception concerns the
treatments subjected to the combination of both N: P: K and farmyard manure, which showed
increasingly high means of 11.1 mm, 19.6mm and 20.3mm. The plants subjected to farmyard
manure, and the combination of both N: P: K and farmyard were not significantly different at
the 39th day after transplanting. The significant difference was observed in the treatment with
N: P: K by about 10 % compared to the control. The treatments of the combination of N: P: K
and Farmyard manure, farmyard manure alone and N: P: K did not show any significant
difference from the 46th day up to the 53rd day after transplanting. The highest effect was
given by the combination of N: P: K and Farmyard manure by 23.6% compared to the control
at 46th day and by 15.7% compared to the control at the 53rd day. However, the difference was
observed in the control at the 46th day after transplanting.
Table 5: Effects of organic and inorganic fertilizers on stem diameter (mm) of Collard
15th day 25th day 32nd day 39 days 46th day 53rd day
Control 7.6b* 14.3b 14.5b 17.5c 19.0b 21.3a
N:P:K and FYM 11.1a 19.6a 20.3a 20.2a 23.5a 24.6a
FYM 8.0b 14.0b 16.6b 20.1ab 22.2a 24.1a
N:P:K 8.4b 15.1b 17.8ab 19.3bc 22.2a 24.3a
*Means followed by the same letters are not significantly different according to Turkey HSD
at P ≤ 0.05
4.5. Effects of organic and inorganic fertilizers on leaf area (cm2) of Collard
The leaf area was recorded at the first harvesting after transplanting to determine the effects of
organic and inorganic fertilizers on leaf area of Collard (Appendix 13 and 45). The treatments
with N: P: K and the combination of both N: P: K and farmyard manure did not show
significant difference. The widest leaf area was observed in plants subjected to the
combination of both N:P:K and farmyard manure with the high mean of 397.2 centimeters
25
square which was 77% higher compared to the control. It was followed by the mean of 355.3
cm2 from the treatment subjected to N: P: K. However the great significant difference was
noted with the plants within treatments in the control and farmyard manure. The leaf area of
plants with Farmyard manure is wider by about 24% compared to the control.
c*
a
b
a
0
50
100
150
200
250
300
350
400
450
Control NPK and FYM FYM NPK
Leaf
are
a in
cm
squ
are
Treatments
25th day
Figure 4: Effects of organic and inorganic fertilizers on leaf area (cm2) of Collard
4.6 Effects of organic and inorganic fertilizers on Fresh weight (grams/plant) of Collard
The fresh leaves were weighted after each harvesting to determine the yield of these fresh edible
leaves in all harvesting intervals. The effects of organic and inorganic fertilizers on fresh weight
of collard varied with time. At the 25th day after transplanting, it was observed that the plants
subjected to the combination of N: P: K and farmyard manure were significantly heavier with the
high mean of 722.8 grams/plant at p ≤ 0.05. It was observed that plants treated with the
combination of N: P: K and farmyard was significantly higher in weight by 102 % compared
with the control. There is no significant difference between the plants under treatments of the
combination of N: P: K and Farmyard manure and plants with N: P: K. the plants subjected to
the Farmyard manure were significantly heavier by about 42% compared to the control.
However, at the 32nd day after transplanting, the plants treated with N: P: K and farmyard was
significantly heavier by about 97.5% compared to the control p ≤ 0.05. During all the period of
experiment, the plants that were subjected to N: P: K and farmyard manure were the same in
26
means of leaf weight except for the control, which significantly lowered. Observing the Table 6
below, it is clear that N:P:K+FYM and N:P:K alone were significantly higher in comparison
with the fresh yield weight from FYM alone and the least mean was observed from the control
upon analysis from 39th , 46th and 53rd days after transplanting However, It has been observed
that the plant under the combination of N: P: K and Farmyard manure were the heaviest with the
identical high means of 542.3g; 552.0g; 816.7g respectively at the 39th day; 46th day 53rd day
after transplanting.
Table 6: Effects of organic and inorganic fertilizers on Fresh edible yield of Collard
25th day 32nd day 39 days 46th day 53rd day
Control 356.2c* 256.7c 222.8c 234.3c 402.6c
N:P:K and FYM 722.8a 507.0a 542.3a 552.0a 816.7a
FYM 505.8bc 356.0b 371.1b 428.9b 569.6b
N:P:K 585.0ab 404.0b 465.1ab 480.9ab 758.8a
*Means followed by the same letters are not significantly different according to Turkey HSD at
p≤ 0.05.
4.7 Effects of organic and inorganic fertilizers on oven-dry mass of edible leaves of
Collard
The oven-dry mass of edible leaves was taken again after each harvesting to determine the yield
of these edible leaves after all experiment. The effects of organic and inorganic fertilizers on dry
mass of collard also varied with the time. Observing the Table 7. below, it was noted that the
treatments subjected to the combination of N:P:K and Farmyard manure have got the highest
means during the time of trial in increasing manner with the high mean of 494 g/plant at the 53rd
day after transplanting. This has been followed by the treatment with N: P: K only in addition it
has been observed that there was no significant difference between the treatments with
combination of both N: P: K and Farmyard manure and the one with N: P: K only at P ≤ 0.05
from 25th day up to the 53rd day after transplanting. The plants subjected to the Farmyard manure
were significantly heavier by about 30.9% compared to the control and significantly lower by
69.8% from the leading treatment at P ≤ 0.05.
27
Table 7: Effects of organic and inorganic fertilizers on oven-dry mass of edible leaves ofCollard
25th day 32nd day 39 days 46th day 53rd day
Control 162.0c* 116.2c 100.4c 121.3c 222.3b
N:P:K and FYM 398.4a 305.0a 327.7a 321.4a 494.3a
FYM 231.6bc 155.2bc 164.8bc 191.3bc 291.1b
N:P:K 298.5ab 213.4b 242.6ab 232.5ab 378.9ab
*Means followed by the same letters are not significantly different according to Turkey HSD at
p≤ 0.05.
4.8 Effects of organic and inorganic fertilizers on Total fresh weight and Total oven-dry
mass of Collard
The effect of Fertilizers on fresh edible leaves weight varied significantly in all treatments,
thus the treatment subjected to the combination of both N: P: K and farmyard manure showed
significantly high mean of 223.0 t/ha. This was followed by the treatment under N: P: K with
the mean of 191.7t/ha. In addition, the high mean was significantly higher by about 113%
compared to the control. However the figure 5; 6; 7 and the appendices 49, 50,51and 52
demonstrated that either in total fresh weight or in total oven-oven dry weight, the plants
within treatments treated with the combination of both N:P:K and Farmyard were
significantly different and heavy compared to other treatments. The plants under N: P: K
treatment followed in all cases followed by the plants subjected to Farmyard manure, while
the control lowered in all considerations as it is shown in the Table 8 bellow. Guertal and
Edwards (1996) reported fall collard yields of 10,400 – 14,700 kg /ha if harvested once using
various mulches, and Mulvaney MJ 2006, reported that the Collard yield averaged 23,109 ±
6411 kg /ha (standard deviation) if harvested once, so the yields in this study are within the
expected range for the area.
13
d*
a
c
b
d
a
cb
0
500
1000
1500
2000
2500
3000
3500
Control FYM andN:P:K
FYM N:P:KFertilizers
Fres
h ed
ible
yie
ld g
/pla
nt
Freshedibleyield ingrams/plant
Oven-drymass ofedibleyield ingrams/plant
Figure 5: Effects of organic and inorganic fertilizers on total fresh weight and totaloven-dry mass of Collard (in grams).
d*
a
c
b
d
a
gb
0
50
100
150
200
250
Control FYM and N:P:K FYM N:P:K
Yie
ld in
T/h
a
Total freshedible yieldin t/ha
Total oven-dry mass ofedible yieldin t/ha
Fertilizers
Figure 6: Effects of organic and inorganic fertilizers on total fresh weight and totaloven-dry mass of Collard(T/ha).
14
d
d
a
a
c
c
b
b
0
50
100
150
200
250
Yie
ld in
T/h
a
Control FYM andN:P:K
FYM NPK
Treatments
Total freshbiomass in inT/haTotal oven-dry biomass inT/ha
Table 8: Effects of organic and inorganic fertilizers on total fresh biomass and totaloven-dry biomass of Collard (in T/ha).
13
CHAPTER FIVE
DISCUSSION
5.1. Effects of organic and inorganic fertilizers on soil chemical properties after
transplanting of collards
The results of pH-water observed after transplanting were ranging from 5.76 to 5.82 with
the highest value of 5.8 in the Treatments subjected to the combination of N: P: K and
farmyard and in the one treated with Farmyard only. The lowest value was observed in the
control. According to the interpretation standards established by Mutwewingago and
Rutunga (1987), the soil of the experimental site range in fairly acidic soil. (pH 5.2-6.2).
In this study, the decrease of pH value from 5.83 to 5.76 has been influenced by the
decomposition of existing organic matter because organic matter in form of plant litter,
compost, and manure will decrease soil pH through the decomposition.(Brady and Well
2002).
The total Nitrogen content varied from 0.21% to 0.30% after transplanting with the
average of 0.23 % before transplanting. According to interpretation standards of total
nitrogen established by Mutwewingago and Rutunga (1987), this soil nitrogen content is
between 0.2-0.5 percent which high class is. The increase was observed respectively in
treatments subjected to Farmyard manure, combination of both N: P: K and farmyard
manure and N: P: K only. This may resulted to mineralization of organic matter and due to
the application of nitrogen-containing fertilizers (20t/ha of FYM; 150 kg of N: P: K /ha +
10 t/ha of FYM; and 300 kg of N: P: K /ha as it was reported by Palm and al., (2000).
According to Raymond and al, (1990), organic matter is the major source of total nitrogen
into the soil (90 to 95%).that is why the nitrogen rate increased in the soil as Farmyard
manure is increased into the soil.
It was observed also that the treatments received Farmyard manure, the combination of
both Farmyard manure and N: P: K and N: P: K only showed the variation in available
Phosphorus from 29.92 ppm to be respectively: 54.1, 43.7 and 30.3 ppm while it reduction
from the control. The data of available phosphorus in this experimental site ranged
between 20 to 50 ppm. According to Mutwewingago and Rutunga (1987), this soil is in
the category of moderate available phosphorus except in the treatment that received
Farmyard manure only which was found in high availability of phosphorus upon soil
14
analysis. The increase in available phosphorus may be caused by decaying plant and
animal residues, humus, and microorganisms as it was reported by Steven and Hodges
(2002). The combination of organic source of Phosphorus and inorganic Phosphorus, can
lead to the release of Phosphorus by mineralization of organic matter. These results are not
far from the one found by Nyirarukundo (2011) under Busogo conditions where high
value in available Phosphorus resulted from the accumulation of organic matter and
decomposition released high quantities of Ca from organic matter and increased
availability of Phosphorus. Steven C. Hodges (2002)
The results obtained on soil potassium showed that the soil potassium content was 0.78
meq/100g of soil and varied from 0.42 meq/100g to 1.14/100g of soil. The treatments
treated with Farmyard manure and the one with the combination of both N: P: K and
Farmyard manure showed high mean followed by the treatment with N: P: K only whereas
the control decreased. Potassium does not move readily in most soils especially in soil
enriched in organic matter. However, on sandy soils with low CEC, potassium can move
by mass flow, and loss from the surface soil can be significant, especially after periods of
heavy rainfall. That is why we may say that the decrease of potassium in the control and in
the treatment subjected to farmyard manure is due to low amount of organic matter and
thus high rate of leaching. Another reason can be explained by high rainfall level
experienced during the experiment. This was stated by Steven C. Hodges (2002) that the
Loss of K is minimized by implementing good erosion control practices; maintain good
soil pH to increase soil CEC, building soil organic residues where possible, and using split
applications to reduce leaching losses on soils with low CEC. In addition, This is was due
to the addition of potassium-containing fertilizers whereas it decreased in the control
because of excessive use of K by the crop as was reported by Steven C. Hodges (2002)
that the availability of soil potassium depends primarily on the types and amounts of soil
minerals present in the soil and the absorption of the crop. According to Mutwewingago
and Rutunga (1987), the data were ranging between 0.6-1.2 which is in category of high
availability of potassium.
The results from soil analysis showed also that the average of organic carbon was 2.7%
before transplanting while the high value was observed in treatments treated with
farmyard manure. The range was between 2.4% and 2.9%. According to Henry et al.,
15
(1997), long term application of organic manure is expected to increase organic carbon
and humus content of the soil. Therefore the increase in organic carbon was due to
decomposition of farmyard manure which was buried during ploughing. In addition it has
been observed that the high value of Carbon to Nitrogen ratio was high in the control and
low in treatment with Farmyard manure with the range of 9.56% and 12.35% after
transplanting. According to Tom and Nancy (1996) the higher the C/N ratio the lower will
be the mineralization thus the experimental site was in quick mineralization category
according to the norms of Mutwewingago and Rutunga (1987).
5.2. Effects of organic and inorganic fertilizers on plant height of Collard in cm
The results observed in this study indicated that the height of collard at different stage of
growth was highly influenced by treatments. At 15th day after transplanting there was
significant difference between treatments with the highest mean of 14.6 cm in treatment
subjected to N:P:K followed respectively with the combination of both N:P:K and
Farmyard and the treatment of Farmyard. The height response to fertilizers was due to
nitrogen amount which is responsible for shoots and leaf growth. The soil potassium is
also important in the breakdown of Carbohydrates, in the process which provides energy
for plant growth as reported by Gupta, (2004). A good supply of Nitrogen is associated
with vigorous growth and a deep green color whereas the plants deficient in N become
stunted and yellowing appearance (Steven and Hodges 2002).The last one was observed in
the control, where no fertilizer was applied, this was due to the lack of nutrients required
by the plant. During 25th; 32nd; 39th; 46th; 53rd day after transplanting, the plants subjected
to N: P: K, combination of both N: P: K and Farmyard manure, and Farmyard manure
alone were not significantly different in terms of height. This response of plants height to
the fertilizers may the consequences of availability on macro elements in the soil and thus
high photosynthetic activities as it was explained by Miller and Donahue (1990), who
stated that the soil reaction affect the plant growth by applying mineral fertilizer. By using
farmyard manure, nutrients content of the soil are improved and microbial activity of
decomposing and mineralization of applied Farmyard manure get enhanced and this leads
to release of plant nutrients which influence plant growth and yield in general.
5.3. Effects of organic and inorganic fertilizers on number of leaves of Collard
16
The mean numbers per plant was from 6.4 to 7 at the 15th day which shows that there was
no significant difference upon analysis at P ≤ 0.05. The identical means also were found at
the 25th day eventually with high means in plants within in the treatments subjected to N:
P: K.. Here also the explanation which may be given by the fact that the plots receiving a
combination of organic and inorganic fertilizers produced slightly higher number (P>0.05)
is that Nitrogen is involved in photosynthesis. That is why an adequate supply of Nitrogen
is associated with high photosynthetic activity and vigorous vegetative growth (Miller and
Donahue1990).
5.4. Effects of organic and inorganic fertilizers on stem diameter of Collard
The means comparison of stem diameter has shown that the combination of both N: P: K
and Farmyard manure were significantly higher in all treatments from the 15th, 25th day
up to 32nd day whereas other treatments were not significantly different could be due to
effect of potassium which is responsible of both growth and size of the stem as explained
by Munson et al., (1985) and cited by El-Sirafy et al., (2008). During the decomposition
of organic matter, soil microorganisms convert organic nitrogen into ammonium (NH4+)
and nitrate (NO3-) forms of nitrogen which plants utilize. Its combination with mineral
fertilizer may increase vegetative growth (Engel et al, 2001). At the 39th day; 46th day;
and 53rd day both treatments with the combination of N: P: K and farmyard manure and
the one with farmyard manure only were not significantly different each other and were
the best in terms of stem diameter. This is due to the quick mineralization of organic
matter, which leads to the release of macro elements and thus increases in stem growth. It
was also seen that at the 53rd day after transplanting the plants had the identical means
although the high mean was in the treatment under combination of organic and inorganic,
this is because the plant had attained their optimum growth in terms of stem diameter.
17
5.5. Effects of organic and inorganic fertilizers on leaf area of Collard
The data recorded at the first harvesting after transplanting to determine the effects of
organic and inorganic fertilizers on leaf area of Collard, showed that the treatments with
N: P: K and the combination of N: P: K and farmyard manure did not show significant
difference thus the widest area was observed in plants subjected to the combination of
both N: P: K and farmyard manure with the high mean of 397.2 centimeters square. This
mean is significantly higher by about 77% compared to the control. It is followed by the
mean of 355.3 cm2 from the treatment subjected to N: P: K. This variation might be due to
the availability of nutrients especially nitrogen and could be due to the improvement of
soil water holding capacity as mentioned earlier by Roe and Cornforth (2000).
Furthermore, organic manure activates many species of living organisms, which release
phytohormones and may stimulate the plant growth and absorption of nutrients (Arisha et
al., 2003). Such organisms need nitrogen for multiplication. This is possible reason that
the use of organic manure with inorganic fertilizer showed a beneficial effect on leaf area.
However the decline may be associated to low nitrogen content in the control. This has
been stated by Steven and Hodges (2002).
5.6. Effects of organic and inorganic fertilizers on Fresh and oven-dry mass of edible
leaves of Collard
The results of this study indicate that both Fresh and oven-dry mass of edible leaves of
Collard responded much stronger to the combination of both N: P: K and Farmyard
manure levels than N: P: K alone or Farmyard manure alone Negative effects of excessive
application of N on biomass production was documented for several crops (Robert et al.,
1989), including Brassica oleracea L. var. Acephala. (Chweya, 1997). Nkoa et al., (2003),
suggest that biomass reductions caused by excessive N applications may be the result of
osmotic imbalances due to N accumulation in plant tissues. In addition the decline in
treatments subjected to Farmyard manure and in the control can be justified by low
amount of N: P: K rate in the soil. These either fresh or oven-dry mass of edible leaves
were relatively in concordance with the results of leaf areas found above.
18
5.7. Effects of organic and inorganic fertilizers on Total fresh weight and Total oven-
dry mass of Collard
The effect of Fertilizers on fresh edible leaves mass has varied significantly in all
treatments, thus the treatment subjected to the combination of both N: P: K and Farmyard
manure showed significantly high mean of 223.0 t/ha. This was followed by the treatment
under N: P: K with the mean of 191.7t/ha. In addition, the high mean was significantly
higher by about 113% compared to the control. However the appendix 49; 50; 51 and 52
demonstrated that either in total fresh weight or in total oven-dry weight, the plants within
treatments treated with the combination of both N: P: K and Farmyard were significantly
different and heavy compared to other treatments. The plants under N: P: K treatment
followed in all cases followed by the plants subjected to farmyard manure, while the
control lowered in all considerations as it is shown in the table The plants under N:P:K
treatment followed in all cases followed by the plants subjected to Farmyard manure,
while the control lowered in all considerations as it is shown in the Table 8. Guertal and
Edwards (1996) reported fall collard yields of 10,400 – 14,700 kg /ha if harvested once
using various mulches, and Mulvaney, 2006, reported that the Collard yield averaged
23,109 ± 6411 kg /ha (standard deviation) if harvested once, so the yields in this study are
within the expected range for the area. In addition, the results in terms of growth and yield
are in accordance with those obtained by Shiralipour and Faber (1996) on broccoli
(B.oleraceavar Italica); Wong et al. (1990) and Magnusson (2002) on chinensis cabbage
(B. chinesis) and Abdelrazzag (2002) on onion (Allium cepa). The highest yield of leaves,
fresh and dry weights of collards were obtained by application of 10toness/ha of Farmyard
manure with 150kg/ha of inorganic fertilizer (N:P:K). This variation was due to the
availability of nutrients especially nitrogen and potassium and could be due to the
improvement of soil water holding capacity as mentioned earlier by Roe and Cornforth
(2000). Furthermore, organic manure activates many species of living organisms, which
release phytohormones and may stimulate the plant growth and absorption of nutrients
(Arisha et al., 2003). Such organisms need nitrogen for multiplication. This is the reason
that the use of organic manure with inorganic fertilizer showed a beneficial effect on both
fresh and oven-dry matter.
19
CHAPTER SIX
CONCLUSION AND RECOMMENDATIONS
6.1 Conclusion
This research was carried out in order to evaluate the effect of organic and inorganic
fertilizers on growth and yield of collards. To achieve this objective, those fertilizers were
applied in various plots laid out in randomized complete blocs with three replicates.
According to the results obtained after trial I come with the following conclusions:
1) The results of soil analyses after experiment compared to the initial soil analysis prove
that the mineral and organic fertilizers applied individually or as combination have
improved the soil status and nutrients content in the soil. The exception was always
observed in the control or smoothly in the treatment with N: P: K only.
2) The combination of both farmyard manure and N: P: K revealed a positive impact on
growth of agronomic parameters such as: plant height, number of leaves, stem
diameter and leaf area. This research demonstrated the effects of N: P: K containing
fertilizers and Farmyard-containing fertilizers were different over the time in terms of
plant height, stem diameter and the yield of collards. Collard plants grown in soil
amended with the combination of both Farmyard manure and N:P:K have shown a
vigorous vegetative growth (leaf area, fresh and dry weights), and high yield compared
to the application of either N:P:K or Farmyard manure alone.
3) Based on the results of yield obtained after harvesting, farmyard manure and N: P: K
combined together demonstrated better results on collard yield. The combination of
Farmyard and N: P: K have given 223.0 t/ha yield in average of fresh edible leaves; the
N: P: K alone have resulted 191.7 t/ha yield in average of fresh edible leaves, farmyard
manure has given 158.0 t/ha while the control gave 104.7 t/ha; with respectively 131.0
t/ha; 97.0 t/ha; 73.3t/ha and 51.0t/ha of oven-dry mass of edible leaves. This yield is of
great importance since it may be obtained within short period compared to other
Brassica and can be harvested sequentially.
20
6.2 Recommendations
According to the results obtained in this experimentation, the following recommendations
can be mentioned:
1. The combination of both farmyard manure (10 t/ha) and N: P: K (150 kg/ha)
should recommended for the farmers to increase collards production.
2. The use of organic matter completely decayed also is advisable and should be
promoted to improve chemical, physical and biological condition of the soil and
thus leading to the high yield.
3. Further studies are needed to determine optimal rates of organic fertilizers for
proper growth and production of collards in all corners of the country.
21
REFERENCES.
ABDELRAZZAG, A., 2002. Effect of chicken manure, sheep manure and inorganic
fertilizers on yield and nutrient uptake by onion. Pakistan J. Biol. Sci., 5: 266–8.
AGBOOLA, A.A. AND J.A. OMUETI, 1982. Soil fertility problem and its
management in tropical Africa. Paper presented at the International Institute of
Tropical Agriculture, Ibadan, Nigeria. pp: 25.
AMBROSONE CB, TANG L. Cruciferous vegetable intake and cancer prevention: role
of nutrigenetics. Cancer Prev Res (Phila Pa). 2009 Apr;2, )
AMKHA, S., T. MICHIKO, C. SAGWANSUPYAKORN,.SUKPRAKAN AND I.
KAZUYUKI, 2006. Effect of amount of nitrogen fertilizer on early growth of
leafy vegetables in Thailand. Nettai Nogyo., 50(3):pp. 127-132.
ARISHA, H.M.E., A.A. GAD AND S.E. YOUNES, 2003. Response of some pepper
cultivars to organic and mineral nitrogen fertilizer under sandy soil conditions.
Zagazig J. Agric. Res., 30: 1875–99
AYOOLA O.T. AND 2E.A MAKINDE,2007.Complementary Organic and Inorganic
Fertilizer Application: Influence on Growth and Yield of Cassava/maize/melon
Intercrop with a Relayed Cowpea.
BELAY, A., A.S. CLASSENS, F.C. WEHNER AND J.M. DE BEER, 2001. Influence
of residual manure on selected nutrient elements and microbial composition of
soil under long–term crop rotation. South Africa J. Plant and Soil, 18: 1-6.
BERRYMAN, C (1965) ‘Composition of organic manures and waste products used
agriculture’ N.A.N.S advisory paper Nº2.
BRADY, N. AND WELL, R. The nature and properties of soils.13th ed.2002
CHWEYA JA (1997) Genetic enhancement of indigenous vegetable in Kenya. In:
Guarino L (ed.) Traditional African Vegetables. Proc. IPGRI Int. Workshop on
Genetic Resources of Traditional Vegetable in Africa, University of Nairobi
Kenya. International Plant Genetic Resources Institute (IPGRI), Rome. 86-95
COOKE, G. W. 1972 ’Fertilizing for maximum yield.
COOKE, G.W.1968, The control of soil Fertility; London; Crosby Lockwood Ltd.
COOPER, P.J.M., LEAKEY, R.R.B., RAO, M.R. & REYNOLDS, L.1996.
Agroforestry and the mitigation of land degradation in the humid and sub-humid
tropics of Africa. Experimental Agriculture 32(3), 235-290.
DILIP KUMAR DAS,1996: Introductory Soil science; first edition,195-440pp.
22
FOWKE JH, MORROW JD, MOTLEY S, ET AL. 2006) Brassica vegetable
consumption reduces urinary F2-isoprostane levels independent of micronutrient
intake. Carcinogenesis, October 1, 2006; 27(10):2096-2102.2006.
GUERTAL EA, EDWARDS JH 1996 Organic mulch and nitrogen affect spring and
fall collard yields. Hortscience 31, 823-826.
GUPTA, A.P., S.R. ANTIL AND P.R. NARWAL, 1988. Effect of farmyard manure on
organic carbon, available N and P contents of soil during different periods of
wheat growth. J. Indian Soil Sci., 36: 269–73
GUPTA, I.C.2004: A handbook of soil, fertilizer and manure, Agrobios, India, 335-
345p.
J. WANJIKU & J. UHURU MANYENGO, (2009).
JAMA and PALM, (2000).Tithonia diversifolia as green manure for soil fertility
improvement in Western Kenya, Nairobi, Kenya P.201-221.
KORUS AZL (2009) Effect of Cultivar and Harvest Date of Kale (Brassica Oleracea L.
Var. Acephala) on Content of Nitrogen Compounds. Published in. Polish journal
of environment Studies. Vol18 (2) p. 335-241.
Lorenz,O.A. and Maynard , D.N. (1980). Knott’s Handbook for Vegetable Growers. 2nd
Edition. John Wiley and Sons inc. USA.
MAGNUSSON, M., 2002. Mineral fertilizers and green mulch in Chinese cabbage
(Brassica pekinensis rupr): effect on nutrient uptake, yield and internal tipburn.
Soil Plant Sci., 52: 25–35
MILLER .W.R and DONAHUE. R.L 1990: Soils An introduction to soils and plant
growth; Sixth edition; new Jersery, USA. 181-250pp.
MINAGRI (2007) Politique Agricole nationale, Kigali, pp.80.
MINAGRI, (2010).Farmer’s diary. National Agriculture Extention Support Project
(PASNVA) in collaboration with RADA.
MINAGRI, may 2006; Horticulture action plan , Full version, Kigali Rwanda, pp.20
MINAGRI/SPSPAT, 2008: Support Project to Strategic Plan for Agricultural
Transformation. Kigali, Rwanda. PP.53.
MINALOC (2006), Ministry of local government. Monography of Musanze District.
MULVANEY MJ,2006, Biomass shifts and suppresses weed populations under
Conservation Agriculture.
23
MUNYEMANA and VON OPPE, M.,(1999). La pomme de terre au Rwanda: une
analyse d’une filiere a haute potentialite, Kigali,Rwanda.P 72.
MUTWEWINGABO, B. et RUTUNGA, V. 1987: Etude des sols des stations
NKOA R, COULOMBE J, DESJARDINS Y and TREMBLAY N (2000) toward
optimization of growth via nutrient supply phasing: nitrogen phasing increases
broccoli (Brassica oleracea var. italica) growth and yield. J. Exp. Bot. 52 821-
827.
PARR, J.F. AND S.B. HORNIC, 1995. Transition from conventional agriculture to
nature farming systems:The role of microbial inoculants and organic fertilizers.
pp: 25. Paris,France.
PEARCY, R. W., J. EHLERINGER, H. A. MOONEY, AND P. W. RUNDEL. (EDS).
1989. Plant physiological ecology: Field methods and Instrumentation. Chapman
and Hall. N. Y., pp. 305. Leaf length and width measurement.
RAYAR, A. J. 2000: Sustainable agriculture in sub-saharan Africa. The role of soil
productivity, AJR publication-chennai, India, 21p,172-173p.
RAYAR, A.J. 2004 A handbook on soil fertilization.ISAE-BUSOGO.
ROBERT K, HAY M and WALKER AJ (1989) An Introduction to the Physiology of
Crop Yield.
ROE, E.N. AND C.G. CORNFORTH, 2000. Effect of dairy lot scraping and
composted dairy manure on growth, yield and profit potential of double-cropped
vegetables. Compost Sci. and Utilization, 8: 320–7.
SALLY MORTON (2007), Collard green and lettuce.
SANCHEZ, P.A., BURESH, R.J. & LEAKEY, R.R.B. 1997. Trees, soils and food
security. Philosophical Transactions of the Royal Society of London Series B
352(1356), 949-961.
SHARMA, A.R. AND B.N. MITTRA, 1991. Effect of different rates of application of
organic and nitrogen fertilizers in a rice-based cropping system. Journal of
Agricultural Science (Cambridge), 117: 313-318.
Shiralipour, A. and B. Faber, 1996. Greenhouse Broccoli and Lettuce growth using
composted bioslids. Compost Sci. and Utilization, 4: 38–44.
SORENSEN, J.N., 1996. Improved N efficiency in vegetable production by fertilizer
placement and irrigation. Acta Horticulturae, 428: 131-140.
Steven and Hodges, soil fertility basics, Chapter 12 Nutrient Management & Realistic
Yields – 69.
24
TOM RICHARD AND NANCY TRAUTMANN(1996) Cornell University
Ithaca,NY14853607-255-1187.
WONG, H.M., 1990. Comparison of several solid wastes on the growth of vegetable
crops. Agric. Ecosys. Envirn., 1: 49–60.
YOUNG, Y.C., O. SUNGBONG, O. M. MYOUNG, AND J. E. SON. 2007. Estimation
of individual leaf area, fresh weight and dry matter of hydroponically grown
cucumbers (Cucumis sativus L.) using leaf length, width and SPAD value.
Scientia Horticulturae 111(4): 330-334.
ZULKIFLI H. SHAMSUDDIN AND AHMAD HUSNI M.H,1994: combined use of
chemical and organic fertilizers.
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APPENDICES
The results of soil analysis
Appendix 1:1Soil pH after harvesting after trial
Ttt Bloc1 Bloc2 Bloc3 Average
T1 5.80 5.77 5.73 5.76
T2 6.04 5.64 5.78 5.82
T3 5.79 5.62 6.06 5.82
T4 5.84 5.59 5.96 5.79
Appendix 2: Nitrogen rate after harvesting (%)
Ttt Bloc1 Bloc2 Bloc3 Average
T1 0.17 0.22 0.23 0.20
T2 0.33 0.19 0.24 0.25
T3 0.33 0.27 0.31 0.30
T4 0.27 0.18 0.32 0.25
Calculation:
Total N %=( Absorbance read-blank) x2.2
Exemple: (0.158-0.040) x2.2=0.26
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Appendix 3: Phosphorus rate after harvesting (ppm)
Ttt Bloc1 Bloc2 Bloc3 Average
T1 21.2 23.2 22 22.1
T2 35.2 49.6 46.4 43.7
T3 56 53.6 52.8 54.1
T4 30.4 30.8 29.8 30.3
Calculation:
P (ppm)= absorbance-blanc x f.cx f.d
Where : f.c=(facteur de correction) =109
f.d =(facteur de dilution)= 10/3
Appendix 4: Potassium rate after harvesting (meq/100g)
Ttt Bloc1 Bloc2 Bloc3 Average
T1 0.39 0.4 0.47 0.42
T2 0.38 0.29 0.36 1.03
T3 1.19 0.76 1.49 1.14
T4 0.97 1.2 0.74 0.97
Calculation :
Kmeq/100gr = (absorbance – blanc) x 165x3
f.c:165
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Appendix 5: Organic carbon after transplanting
Ttt Bloc1 Bloc2 Bloc3 Average
T1 2.63 2.43 2.43 2.6
T2 2.8 2.65 2.7 2.7
T3 3 2.55 3.15 2.9
T4 2.5 2.4 2.4 2.4
Calculation :
% C = (absorbance – blanc) x 80x100x1/1000x f.c
Note that 80x100x1/1000xf.c= 5
That’s to say % C= (absorbance-blanc ) x 5
Example : (0.61-0.14) x 5 = 2.35 and so on
Appendix 6: Organic matter after harvesting
Ttt Bloc1 Bloc2 Bloc3 Average
T1 4.53 4.19 4.19 4.30
T2 4.83 4.56 4.65 4.68
T3 5.17 4.39 5.43 4.99
T4 4.31 4.14 4.14 4.19
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Appendix 7: C/N ration
Ttt Bloc1 Bloc2 Bloc3 Average
T1 15.47 11.04 10.56 12.35
T2 8 14.7 8.7 10.46
T3 9.1 9.44 10.16 9.56
T4 9.2 13.3 7.5 10
13
Appendix 8: Effect of treatment on soil chemical composition
Treatment PH-eau N (%) P(ppm) K (meq/100g) C (%) O.M C/N
Initial
Soil
Analysis
After Initial
Soil Analysis
After Initial
Soil Analysis
After Initial
Soil Analysis
After Initial
Soil Analysis
After Initial
Soil
Analysis
After Initial
Soil
Analysis
After
T1
5.83
5.76
0.23
0.20
29.92
22.1
0.78
0.42
2.7
2.6
4.65
4.30
11.7
12.35
T2 5.82 0.25 43.7 1.03 2.9 4.68 10.46
T3 5.82 0.30 54.1 1.14 2.9 4.99 9.56
T4 5.79 0.25 30.3 0.97 2.4 4.19 10
13
Appendix 9: Interpretation norms of pH
pH Highly
acidic
Very
acidic
Fairly
acidic
Slightly
acidic
Neutral Slightly
basic
pH water 3.5-4.2 4.2-5.2 5.2-6.2 6.2-6.9 6.9-7.6 7.6-8.5
pH KCL 3.0-4.0 4.0-5.0 5.0-6.0 6.0-6.8 6.8-7.2 7.2-8.0
Source: Mutwewingabo and Rutunga (1987); quoted by Twizeyimana, 2004
Appendix 10: Interpretation norms of O.M and available P, and total N
Organic matter (% of soil) Appreciation
0.5
0.5-1
1-2
2-5
5-8
8-14
>14
Excessively less humic
Very less humic
Less humic
Moderately humic
Humic
Very humic
Excessively humic
Available P(ppm) Appreciation
<3
3-20
Very low
Low
14
20-50
50-80
>80
Moderate
High
Very high
Nitrogen (%) Appreciation
<0.075
0.075-0.2
0.2-0.5
>0.5
Low
medium
High
Very high
C/N ratio Mineralization
≤ 9
9-12
12-17
17-25
≥ 25
Very quick
Quick
Normal
Slow
Very slow
Source: Mutwewingabo and Rutunga(1987);
The results of agronomic parameters observed
Appendix 11: Number of leaves at 15th day after transplanting
Ttt Bloc1 Bloc2 Bloc3 Average
T1 7.25 6.75 6.75 6.916
T2 6.75 7 5.5 6.416
15
T3 7.25 7 6 6.75
T4 8 6.5 6.5 8
Appendix 12: Number of Leaves at 25th days after transplanting
Ttt Bloc1 Bloc2 Bloc3 Average
T1 10.75 10.25 9.25 10.08
T2 10 11.75 10.75 10.83
T3 11.5 9.75 10 10.41
T4 12 11.25 12 11.75
Appendix 13: Leaf area at 25th day after transplanting
Ttt Bloc1 Bloc2 Bloc3 Average
T1 240.052 225.587 206.862 224.167
T2 390.36 389.263 412.05 397.224
T3 262.547 259.499 313.141 278.39
T4 341.527 355.585 368.67 355.260
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Appendix 14: Plant height at 15th day after transplanting
Ttt Bloc1 Bloc2 Bloc3 Average
T1 10.775 10.375 9.95 10.37
T2 12.375 13.3 11.325 12.3
T3 11.5 11.725 12.7 11.975
T4 15.45 14.35 13.875 14.558
Appendix 15: Plant height at 25th day after transplanting (in cm)
Ttt Bloc1 Bloc2 Bloc3 Average
T1 15.75 14.25 12.5 14.16
T2 18.75 19.25 14.375 17.45
T3 15.85 18.25 15.5 16.53
T4 21.25 19.875 21.75 20.95
Appendix 16: plant height at 32th day after transplanting (cm)
Ttt Bloc1 Bloc2 Bloc3 Average
T1 18.375 17.375 17.125 17.625
T2 23.55 22.25 18.125 21.30
T3 19.5 22.375 17.75 19.87
T4 24.626 24.25 22.5 23.79
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Appendix 17: Plant height at the 39th day after transplanting (cm)
Ttt Bloc1 Bloc2 Bloc3 Average
T1 20.125 19.25 18 19.125
T2 24.5 24 21.375 23.291
T3 21.25 23 19.625 21.291
T4 25.25 26 24 25
Appendix 18: Plant height at the 46th day after transplanting
Ttt Bloc1 Bloc2 Bloc3 Average
T1 21.375 20 18.75 20.04
T2 25.825 25 24.475 25.1
T3 25 26.35 21.75 24.36
T4 26.75 26.25 26.025 26.34
Appendix 19: plant height at the 53rd day after transplanting (cm)
Ttt Bloc1 Bloc2 Bloc3 Average
T1 21.875 21.625 21.25 21.58
T2 31 28.25 23.75 27.66
T3 28.625 29.25 25.625 27.8
T4 28.625 29.5 29.25 29.125
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Appendix 20: Stem diameter at 15th day after transplanting (mm)
Ttt Bloc1 Bloc2 Bloc3 Average
T1 7.45 8.635 6.82 7.635
T2 7.912 8.5725 7.675 8.053
T3 7.542 8.7875 7.7375 8.022
T4 8.597 8.7525 7.8325 8.394
Appendix 21: Stem diameter at 25th after transplanting (mm)
Ttt Bloc1 Bloc2 Bloc3 Average
T1 15.325 13.8525 13.62 14.26
T2 16.165 18.96 14.56 16.56
T3 15.4 14.282 12.052 13.91
T4 15.91 15.272 14.135 15.10
Appendix 22: Stem diameter at 32th after transplanting(mm)
Ttt Bloc1 Bloc2 Bloc3 Average
T1 15.467 14.285 13.635 14.46
T2 17.605 18.555 16.75 17.63
T3 17.752 16.677 15.51 16.64
19
T4 16.765 18.177 18.39 17.77
Appendix 23: Stem diameter at 39th day after transplanting (mm)
Ttt Bloc1 Bloc2 Bloc3 Average
T1 17.975 18.32 16.165 17.48
T2 19.465 21.195 20.055 19.57
T3 20.97 19.1725 20.01 20.05
T4 19.835 19.3525 18.72 19.30
Appendix 24 Stem diameter at 46th day after transplanting (mm)
Ttt Bloc1 Bloc2 Bloc3 Average
T1 19.5 18.81 18.8175 19.04
T2 21 24.5875 22.245 22.61
T3 21.0625 23.1 23.4375 22.53
T4 21.875 23.1425 21.447 22.15
Appendix 25: Stem diameter at the 53rd day after transplanting (mm)
Ttt Bloc1 Bloc2 Bloc3 Average
T1 21.75 19.75 22.25 21.25
T2 22.8625 26.1 24.9375 24.63
T3 22.1876 25.25 24.875 24.10
20
T4 22.605 25.6875 24.66 24.31
Appendix 26: Analysis of Variance of soil pH
Source DF Sum of Squares Mean Square F Ratio
Model 3 0.00616667 0.002056 0.0646
Error 8 0.25460000 0.031825 Prob > F
C. Total 11 0.26076667 0.9771
Appendix 27: Analysis of Variance of Total Nitrogen
Source DF Sum of Squares Mean Square F Ratio
Model 3 0.01575833 0.005253 1.5080
Error 8 0.02786667 0.003483 Prob > F
C. Total 11 0.04362500 0.2850
Appendix 28: Analysis of Variance of available phosphorus
Source DF Sum of Squares Mean Square F Ratio
Model 3 1808.9700 602.990 39.4025
Error 8 122.4267 15.303 Prob > F
C. Total 11 1931.3967 <.0001
Appendix 29: Analysis of Variance of available potassium
Source DF Sum of Squares Mean Square F Ratio
Model 3 1.4292667 0.476422 9.9427
Error 8 0.3833333 0.047917 Prob > F
C. Total 11 1.8126000 0.0045
Appendix 30: Analysis of Variance of organic matter
Source DF Sum of Squares Mean Square F Ratio
Model 3 1.2058917 0.401964 4.4663
21
Source DF Sum of Squares Mean Square F Ratio
Error 8 0.7200000 0.090000 Prob > F
C. Total 11 1.9258917 0.0402
Appendix 31: Analysis of Variance of plant height at the 15th day
Source DF Sum of Squares Mean Square F Ratio
Model 3 26.832917 8.94431 16.2163
Error 8 4.412500 0.55156 Prob > F
C. Total 11 31.245417 0.0009
Appendix 32: Analysis of Variance of plant height at the 25th day
Source DF Sum of Squares Mean Square F Ratio
Model 3 71.436875 23.8123 7.3144
Error 8 26.044167 3.2555 Prob > F
C. Total 11 97.481042 0.0111
Appendix 33: Analysis of Variance of plant height at the 32nd day
Source DF Sum of Squares Mean Square F Ratio
Model 3 60.170450 20.0568 5.2779
Error 8 30.401251 3.8002 Prob > F
C. Total 11 90.571701 0.0267
Appendix 34: Analysis of Variance of plant height at the 39th day
Source DF Sum of Squares Mean Square F Ratio
Model 3 59.358073 19.7860 10.1102
Error 8 15.656250 1.9570 Prob > F
C. Total 11 75.014323 0.0043
Appendix 35: Analysis of Variance of plant height at the 46th day
Source DF Sum of Squares Mean Square F Ratio
22
Source DF Sum of Squares Mean Square F Ratio
Model 3 67.471875 22.4906 11.3652
Error 8 15.831250 1.9789 Prob > F
C. Total 11 83.303125 0.0030
Appendix 36: Analysis of Variance of plant height at the 53rd day
Source DF Sum of Squares Mean Square F Ratio
Model 3 101.30599 33.7687 7.7718
Error 8 34.76042 4.3451 Prob > F
C. Total 11 136.06641 0.0093
Appendix 37: Analysis of Variance of number of leaves at the 15th day
Source DF Sum of Squares Mean Square F Ratio
Model 3 0.5989583 0.199653 0.4167
Error 8 3.8333333 0.479167 Prob > F
C. Total 11 4.4322917 0.7459
Appendix 38: Analysis of Variance of number of leaves at the 25th day
Source DF Sum of Squares Mean Square F Ratio
Model 3 4.6822917 1.56076 2.5613
Error 8 4.8750000 0.60938 Prob > F
C. Total 11 9.5572917 0.1279
Appendix 39: Analysis of Variance of stem diameter at the 15th day
Source DF Sum of Squares Mean Square F Ratio
Model 3 0.8671692 0.289056 0.6582
Error 8 3.5134388 0.439180 Prob > F
C. Total 11 4.3806081 0.6003
Appendix 40: Analysis of Variance of stem diameter at the 25th day
23
Source DF Sum of Squares Mean Square F Ratio
Model 3 12.504357 4.16812 1.7501
Error 8 19.053251 2.38166 Prob > F
C. Total 11 31.557608 0.2341
Appendix 41: Analysis of Variance of stem diameter at the 32nd day
Source DF Sum of Squares Mean Square F Ratio
Model 3 21.086386 7.02880 7.5676
Error 8 7.430405 0.92880 Prob > F
C. Total 11 28.516791 0.0101
Appendix 42: Analysis of Variance of stem diameter at the 35th day
Source DF Sum of Squares Mean Square F Ratio
Model 3 14.186110 4.72870 5.8470
Error 8 6.469950 0.80874 Prob > F
C. Total 11 20.656060 0.0205
Appendix 43: Analysis of Variance of stem diameter at the 46th day
Source DF Sum of Squares Mean Square F Ratio
Model 3 26.222058 8.74069 5.9226
Error 8 11.806616 1.47583 Prob > F
C. Total 11 38.028674 0.0198
Appendix 44: Analysis of Variance of stem diameter at the 53rd day
Source DF Sum of Squares Mean Square F Ratio
Model 3 22.071141 7.35705 3.0359
Error 8 19.386688 2.42334 Prob > F
C. Total 11 41.457829 0.0929
Appendix 45: Analysis of Variance of leaf area
24
Source DF Sum of Squares Mean Square F Ratio
Model 3 32693.536 10897.8 6.5155
Error 8 13380.866 1672.6 Prob > F
C. Total 11 46074.402 0.0153
Appendix 46: Analysis of Variance of fresh weight at the 25th day
Source DF Sum of Squares Mean Square F Ratio
Model 3 190204.68 63401.6 2.3896
Error 8 212256.15 26532.0 Prob > F
C. Total 11 402460.83 0.1444
Appendix 47: Analysis of Variance of fresh weight at the 39th day
Source DF Sum of Squares Mean Square F Ratio
Model 3 107854.05 35951.4 13.5254
Error 8 21264.53 2658.1 Prob > F
C. Total 11 129118.59 0.0017
Appendix 48: Analysis of Variance of fresh weight at the 53rd day
Source DF Sum of Squares Mean Square F Ratio
Model 3 230383.07 76794.4 10.0779
Error 8 60960.82 7620.1 Prob > F
C. Total 11 291343.89 0.0043
Appendix 49: Analysis of Variance of total fresh weight in t/ha
Source DF Sum of Squares Mean Square F Ratio
Model 3 10579.053 3526.35 20.0144
Error 8 1409.527 176.19 Prob > F
C. Total 11 11988.580 0.0004
Appendix 50: Analysis of Variance of total fresh weight in grams/ha
25
Source DF Sum of Squares Mean Square F Ratio
Model 3 8972307 2990769 19.0657
Error 8 1254931 156866 Prob > F
C. Total 11 10227238 0.0005
Appendix 51: Analysis of Variance of Total oven-dry mass in grams/ha
Source DF Sum of Squares Mean Square F Ratio
Model 3 882454.0 294151 16.2240
Error 8 145045.4 18131 Prob > F
C. Total 11 1027499.4 0.0009
Appendix 52: Analysis of Variance of Total oven-dry mass in tones/ha
Source DF Sum of Squares Mean Square F Ratio
Model 3 44.622451 14.8742 16.2240
Error 8 7.334412 0.9168 Prob > F
C. Total 11 51.956863 0.0009
Appendix 53: Picture in the field from the beginning up to the end of the experiment
26