University of The Gambia

By

Abdoulaye Seck

GAMHORT Project Manager

July 2013

1

REPORT ON THE ACTION RESEARCH ACTIVITIES CARRIED OUT ON MICROGARDENING

(2010-2012)

TABLE OF CONTENTS

1. Background

2. Baseline

3. Research justification and objectives

4. Research methodologies

5. Main research findings

6. Conclusions

2

1. Background

Concern Universal’s GAMHORT Project was first focused on conventional horticulture and has worked from 2007 to 2008 in small scale farmer capacity building in North Bank and West Coast Regions where several hundreds of farmers were trained and supported.

Afterwards, CU also needed to support peri-urban and urban communities and through GAMHORT explored and discovered possibilities of collaborating with Senegal. The soilless vegetable production technology or micro-gardening was then introduced in The Gambia by Concern Universal in 2008 for adaptation and dissemination purposes as a component of CU’s poverty alleviation and food security strategy.

The technology was introduced and successfully piloted in 20 sites of the Kombo area with main focus on unemployed household women and youths. In addition, the technology was extended to PLHIVs1 through the Mutapola net work involving mainly women. Later on, other beneficiaries were involved through the Gambian lower basic schools where students were targeted and through specialized education institutions (e.g. GOVI2 and GADHOH3). Since the performance of the technology was discovered and confirmed from the beginning, the need was felt to adapt it to the Gambian realities for sustainability purposes. As a result, the action research component was implemented.

2. Baseline

The GAMHORT projects funded by UMCOR/FRB were aimed at enhancing the livelihoods of small scale producers through conventional horticultural training. In 2006-2008, over 690 direct beneficiaries were trained in rural areas (West Coast and North Bank Regions) and local production boosted from 55 to 82% of GiG’s purchases (269 tons and D4.2 millions distributed to local farmers).

In order to also reach the poor peri-urban and urban communities and areas where land is a major issue, a new soil less technology was introduced in The Gambia for the first time, successfully tested, and became GAMHORT Micro-gardening project 1.

In both cases where conventional and soilless production techniques have been promoted for the benefit of poor communities, a number of issues were identified as key constraints needing to be tackled to sustain the livelihoods of rural and peri-urban/urban communities.

1 PLHIVs: People living with HIV/AIDS.2 GOVI: Gambian Organization for the Visually Impaired.3 GADHOH: Gambian Association for the Deaf and Hard of Hearing.

3

In conventional horticulture, 4 BSc’s degree theses were supervised by CU in collaboration with the University of The Gambia as summarized in table 1.

Table 1: Action research carried out in conventional horticulture and main findings

Research topics Years Students Overall objective Main findings

Studies on onion bulb yield and quality as influenced by plant density in organic and intensive cropping systems in The Gambia

2009 A.Baldeh

To evaluate the effect of spacing on onion growth and yields in 2 different cultural systems

[Traditional system (TS): beds with only organic matter and manual irrigation;Intensive system: drip irrigation with fertigation system + manure;Densities compared: 444,444; 500,000; 666,666 and 1,041,666 plants/ha].

Onion bulb weight negatively impacted by higher densities (TS);

The marketable bulbs decrease with increased densities;

Net marketable yield is good TS (21T/ha), better in IS (27T/ha) (good response to intensification, less to increased densities;

Total net yield higher with T4 (the highest density);

Bolting, very high decreased with higher densities.

Response of tomatoes (variety F1 Mongal) to varying levels of compost on a sandy loam soil in the western region, the Gambia.

2009F.

Trawally

To investigate possibilities of succeeding tomato intensive production only based on organic matter (Sheep + Goat manure) through comparison of different doses.

[5 doses of manures compared 0 (T1), 5(T2), 15(T3), 25(T4) and 35 T/ha(T5) to reduce dependency to chemical fertilisers in favour of manures]

Plant growth, no general significant effect (T5-T1/T2);

Plant earliness, no effect, trend, 16-18 days for flowering;

Net yield and its components: net positive correlation trend: Fruit number: net effect, 3 groups (T1/T2;T3/T4;T4/T5)(10-22 fruits/plant); fruit weight and yield: Net increase with manure doses, 2 groups of significance: T1/T2 (14.4 and 16.2 t/ha) and T3/T4 /T5 (27, 28 and 35 t/ha).

Studies on comparing performances of different tomato hybrids for off-season production in the Gambia

2010 L. Marong

To compare the performances of different tomato hybrids in off-season production.

[4 hybrids compared under intensive conditions (NPK 80-80-160 kg/ha): F1 Ninja, f1 Caribo, F1 Nadira and f1 Mongal] in rainy season.

Plant growth: normal and constant growth, though F1 Ninja and F1 Caribo performed better ;Earliness of flowering; F1 Mongal was the earliest variety but only significantly > toF1 Caribo ;Yield and yield components :

Marketable fruit number per bed varied from 33 fruits (F1 Ninja) to 70 fruits (F1 Mongal) ;

Total fruits number varied from 43 to 83 fruits per bed; high wastages from 16% (F1 Mongal) to 23% (F1 Ninja);

No positive link seen between plant height and yield;

Gross marketable yield varied from 14.5 (F1 Caribo) to 18T/ha (F1 Mongal) and again F1 Mongal and F1 Nadira were > to F1 Ninja and F1 Caribo.

4

In summary, the above described research actions carried out between 2009 and 2011 and focused on key production issues have enabled the following possibilities:

On onion spacing: it has been demonstrated that yield is more linked to crop intensification rather than to plant densities. Small scale farmers depending on production areas, adopt densities going from 1 to 4 folds. Based on Baldeh’s results, it is now well understood that the spacing of 20 cm (between rows) and 10 cm (between plants) is optimum and that rather than increasing density and costs of seeds, fertilizers and manure should be properly supplied for good yields and optimum seed costs;

On organic tomato production: The aim was to demonstrate the possibility of production normally without inorganic fertilizers. The study has shown that yields and yield components have increased together with manure doses from 14 T/ha (no manure) to 35 T/ha (35 T of manure /ha). Further research should be focused on testing higher manure doses to identify the maximum and the optimum doses;

Testing heat tolerant hybrids for rainy season production: the aim was to check which of the currently used hybrids (Mogala dn Nadira) was the most heat tolerant and compare them to 2 other new varieties. The study has demonstrated that F1 Mongal is the best adapted to hot and wet season production, followed by F1 Nadira;

Investigating hybrid tomato NPK fertilizer requirements under adverse growing conditions: in tomato, technicians have always questioned the NPK dose of 120-120-240 (1.2 T of 10-10-20/ha) recommended by Local research and

5

Research topics Years Students Overall objective Main findings

The response of tomato (variety F1 Nadira) to different fertilizer rates on sandy soils in Western Region

2011 H. Bojang

To investigate possibilities of succeeding tomato intensive crops with optimised fertiliser doses, through comparison of different NPK doses.

[Comparison of 5 NPK doses in kg/ha :00-00-00;50-50-100; 60-60-120; 70-70-140; 80-80-160 (+20 T/ha of cow dung)].

Plant growth, net trends, 80-80-160, is the best with 83 cm for final height though no significant difference with 70-70-140 and 60-60-120;Fruit number: net effect with 80-80-160 highest (411 fruits/plot) >all except 70-70-140 (404 fruits);Marketable yield: 80-80-160 (40T/ha) > all but statistically = to 70-70-140 (38 T/ha).

which is not accessible to most small scale farmers. The study was aimed at investigating the optimum dose enabling achieving high yield whilst being affordable to farmers. It has been clearly shown that with 80-80-160 (800 kg of NPK) being dose and cost of at least 33%, it was possible to obtain 38T/ha.

In the micro-gardening component, details of research issues are presented in chapter 3 below.

3. Research justification and objectives in micro-gardening

The overall objective of the first phase (GAMHORT MG1 project) consisted of introducing and promoting the micro-gardening technology in peri-urban, urban and rural areas of The Gambia and building the capacities of 150 youths and women to ensure food availability and income generation. It falls into 4 specific objectives respectively relating to the main targets to be reached (unemployed household women and youths, PLHIVs and to a lesser extent, rural communities).

The project has reached and trained 175 direct beneficiaries (roughly a few hundred people reached indirectly) covering 20 sites in the targeted areas. As a result, a network has been set up with women and youth groups producing their own semi-organic vegetables for consumption and marketing. In particular, the Mutapola women’s network is actively producing vegetables both at their headquarters which is also serving as a demonstration point, and in their respective support group areas. Accordingly, the piloting of the technology has been successful based on results obtained and success stories told by beneficiaries.

The main lessons learned related to a) the need to maintain target sites; b); the need to solve the dependency situation in terms of imported input; c) the necessary support of current beneficiaries and further diffusion of the technology, and d); the need to sustain the technology through the setting up of a revolving fund for beneficiaries to purchase inputs, and mainly reducing costs through research enabling the use of readily available local resources.

As stated in the previous report, further to the successful piloting of the technology (high agronomic performance, good quality produce, increasing interest from beneficiaries, etc.) research into how to sustain this technology was carried out to find solutions for input and accessory availability and affordability such as the following:

Imported fertilisers and pesticides; High costs of tables rendering difficulty in the adoption of the technology;The need for the standard substrates to be simpler for availability purposes, etc.

6

Research areas

Through collaboration with the University of The Gambia (UTG), three (03) BSc. student research theses were implemented under CU’s scientific responsibility on the topics as follows:

Topic 1: “Evaluation of different solid substrates from local resources for sustainable microgardening technology development in urban and peri-urban areas of the Gambia” (by Seedy. Fatty).

This research was aimed at:

Looking at the effects of different local substances used as solid substrates on yield and fruit quality of tomatoes [groundnut shells, rice husks, saw dust and a mixture of these (33. 3 % each)] to be compared to the standard substrate (60 % groundnut shells +20 % rice husks+ 20 % gravels);

Looking at substitution possibilities of wood tables where possible by dug beds filled with the simpler and substrates to reduce acquisition costs.

Topic 2: “Investigating the effect of manure on the quality and yield of vegetables from micro-gardening for substitution purposes to imported fertilizers” (By Ousainou. Sanyang).

Research activities in this area consisted of comparing locally available manures (cow, goat/sheep dung and poultry manure) to imported inorganic fertiliser solutions on yield and quality of vegetables to reduce production costs and improve input availability.

Topic 3: “Testing local manures as a substitute for chemical fertilisers used in the production of tomato in the Gambia” (By Samba. John).

This research work was a follow-up study after preliminary work carried out through topic 2. The aim was to confirm results obtained on possibilities of replacing inorganic fertilizers by animal manures. In particular, pervious research work has demonstrated the good performance of poultry manure as a potential substitute of chemical fertilizer solutions currently used. In addition, this research is based on the simplified substrate consisting of 100% broken groundnut shells to confirm investigation findings in this area. Another specificity of this research relates to the fact that it was conducted during the off season conditions, in which case yield performances were expected to be lower due to increased biotic and abiotic stresses. The expected outputs will include brief descriptions of new organic versions and related costs estimates

7

4. Research methodologies

4.1. Topic 1: “Evaluation of different solid substrates from local resources for sustainable micro-gardening technology development in urban and peri-urban areas of the Gambia” (by Seedy. Fatty).

This research is aimed at testing the effectiveness of simple solid substrates as compared to the mixed standard version for substitution purposes and to improve access to the technology.

Materials and methods

Location: The trial was conducted in Yundum at Concern Universal’s horticultural production and training Farm (GiG Farm);Crop and variety: Tomato hybrid variety F1 Mongal;Substrates used : 5 different substrates (See details below) Planting: Nursery established on 22nd July 2010 and transplanting on august 17th 2010;Irrigation and fertilizer application and care:

NPK through a solution to be applied on a daily basis (6 day/week) at the rate of 20ml in 2 liters of water per table, and

Secondary (Ca, S, Mg) and micronutrients application through a ready-made solution at the rate of 10ml per table in 2 liters of water daily (6 days/week);

Staking of plants to avoid contact of leaves and fruits with the substrate moisture;

Preventive sprayings to control pests and diseases (e.g. early blight with manebe and mite pests with Dicofol).

Experimental Design

9 plants per table (1.2 m2) through a Randomized Complete Block Design (RCBD) with three (03) replicates and five (5) treatments. The studied treatments were the following:

Treatment 1 (T1): Standard substrate (60 % groundnut shells +20 % Rice + 20% gravels);

Treatment 2 (T2): Broken groundnut shells (GNS)100%; Treatment 3 (T3): 100% rice husks; Treatment 4 (T4): 100% saw dust; Treatment 5 (T5): Mixture of T2, T3 and T4 at 33% each.

8

Table 1 below provides details of the experimental design with randomized treatments.

Figure 1: Illustration of the experimental design

Parameters observedThe following six (06) parameters linked to plant growth or development were observed:

Plant height measured at four weeks interval 3 times (measures on 3 plants per table); Plant lateral growth measured once at plant full growth (10 weeks after planting);Days to 50% flowering (Date when 5 plants / 9 are flower);Days to 50% fruiting (Date when 5 plants out of the 9 set fruits);Fruit number per table;Fruit weight per table in kg (weighing total harvest per table);Net yield estimated in T/ha.

Data processingThe data collected were treated with a statistical software (SPSS) to perform a one - criterion analysis of variance (ANOVA 1). In addition, multiple mean comparisons were carried out based on least significant Difference values (LSD) at 5 % probability

Standard (T1) Groundnut (T2) Rice husks (T3) Saw dust (T4) Mixed (T5)

Plate 2: different types of substrates compared on a tomato crop

In addition to conventional micro-garden tables, dug beds have also been tested in order to estimate the extent of cost reduction where possible.

4.2. Topic 2 “Investigating the effect of manure on the quality and yield of vegetables from micro-gardening for substitution purposes to imported fertilizers” (By Ousainou. Sanyang).

9

T3 T2 T4T2 T4 T5T4 T5 T1T5 T1 T3T1 T3 T2

Block 1 Block 2 Block 3

This research is aimed at testing the effectiveness of different locally available manures on a 100% groundnut shell solid substrate as recommended by research topic 1 in replacement of the mixed one. The research is aimed at substituting the standard fertilizer application by manures in order to reduce costs and improve access to the technology by urban and peri-urban communities.

Materials and methods

Location: The trial was conducted in Yundum NARI Horticultural garden Kombo North West Coast Region (Gambia is Good training farm);Crop and variety: Tomato hybrid variety F1 Mongal selected for its fast growth;Substrates used : 5 different substrates (See details below) Planting: Sowing (Nursery) on 30th August 2010 and transplanting on 20th

September 2010 (9 seedlings per table; spacing: 50 cm x 50 cm);Irrigation: Watering was done daily in both morning and evening using watering cans. Only the control treatment has been supplied soluble fertilizers. Two litters of water were applied on one table as a solution of macro and micro-elements at the rate of 10ml of macro elements and 5ml of micro elements mixed in the two litters of water and applied on a daily basis except on Sundays. In addition, the plants were staked 5 weeks after transplanting. Plant protection was preventively and curatively ensured to control the main pests and diseases.

Experimental Design

A Randomized Complete Block Design (RCBD) was used with 4 replications and 5 treatments. Five tables each measuring 1.5m2 was used as a block. Foot path of 1m between blocks and 0.5 between Tables was used;The treatments compared are as follows:

Treatment 1: macro and microelements (15 and 10 ml respectively) Treatment 2 sheep/goat manure Treatment 3 cow dung Treatment 4. Poultry manure Treatment 5 mixture of sheep/goat, cow dung and poultry manure

(See figure 2).

10

T5 T1 T2 T4T1 T3 T1 T2T3 T2 T5 T3T4 T5 T3 T5T2 T4 T4 T1

Block 1 Block 2 Block 3 Block 4

Figure 2: Illustration of the experimental design

Parameters observed and data processingThe six (06) parameters as follows were observed:

a) Days to 50% flowering – when 5 out of the 9 plants flowerb) Days to 50% fruiting-When 5 out of the 9 plants set fruitsc) Plants height was measured from the base of the plant to the tip of the growing

point using a tape measure at 2 weeks intervald) Plant lateral growth was also measured using the tape measure at 8, 10, and

12 weeks after transplanting.e) Number of Marketable and unmarketable fruits f) Net yield.

The data collected were statistically processed an analysis of variance (ANOVA 1). Mean comparison was carried out based on the least significant Difference values (LSD) at 5 % probability.

4.3. Topic 3: Testing local manures as a substitute for chemical fertilisers used in the production of tomato in the Gambia” (By Samba. John).

This research has built on recommendations from previous work and is aimed at:

Comparing diverse types of local organic matters including poultry manure and the inorganic fertiliser solutions as a control;

Selecting the best combinations or versions on basis of different parameters, and

Working out access cost and proposing the cheapest versions to users.

Material and methods

Location: The trial was conducted at Wellingara Lower Basic School;Crop and variety: Tomato hybrid variety F1 Mongal;Substrate: 100% groundnut shells recommended by CU’s recent research (Fatty, 2010) in replacement of the standard mixture, not always available to farmers;Planting: Sowing (Nursery) on 11th July 2012 and transplanting on 22nd

August 2012 (9 seedlings per table; spacing: 30 cm x 40);Irrigation and care: The plants were staked at 35 days after transplanting. Watering was done daily (2 liters per table morning and evening) except on the check treatment receiving 1.5 and 1 bottle covers of macro and micro elements respectively in 2 liters of water/table in the morning); in addition,

11

plants were preventively and curatively treated to combat the main pests and diseases;Fertilizer application: 5 treatments to be compared, including treatment 1 (the control) normally supplied on a daily basis with chemical fertilizer solutions unlike treatments 2, 3, 4, and 5, which received a total of 6.25 kg of manure per table (different types): basal application of 2.5 kg followed by 3 splits applications of 1.25 kg at four weeks interval.

Experimental Design

A Randomized Complete Block Design (RCBD) was used with four (4) replications and five (5) treatments. Blocks consisted of five (05) tables each measuring 1.2 m2 as described above.

The compared treatments are detailed as follows:

Treatment 1 (T1): standard fertilizer application (macro and micro elements daily applied);Treatment 2 (T2): 100% groundnut shell dust;Treatment 3 (T3): 100% poultry manure;Treatment 4 (T4): 75% groundnut shell dust plus 25% poultry manure;Treatment 5 (T5): 75% poultry manure plus 25%groundnut shell dust.

Figure 3 below provides details of the experimental design with randomized treatments.

Figure 3: Illustration of the experimental design

Parameters observedThe following six (06) parameters linked to plant growth or development were observed:

Days to 50% flowering (days after planting when 5 plants / 9 are flowering);Days to 50% fruiting (when 5 plants out of the 9 plants started setting fruits);

12

T3 T1 T3 T2T5 T5 T1 T4T4 T4 T5 T1T1 T2 T2 T3T2 T3 T4 T5

Block 1 Block 2 Block 3 Block 4

13 harvests, 55 g/fruit (38-

127 g), 42 T/ha

Plant height measured at four weeks interval (measures on 3 plants per table); Plant lateral growth measured once at plant full growth;Fruit number per table (obtained by counting all fruits harvested on each table);Fruit weight per table in kg determined by weighing total harvest per table as the basis of net yield estimate (T/ha).

Data processingThe data collected were treated with a statistical software (MStat C) to perform a one - criterion analysis of variance (ANOVA 1). In case of significant differences multiple mean comparisons are carried out based on least significant Difference values (LSD) at 5 % probability.

5. Main research findings and discussion

5.1. Topic 1 (on solid substrates)

Dug beds

20 cm deep beds were filled with broken groundnut shells and planted with different vegetable species (hybrid tomatoes, cucumbers, cauliflowers, etc.) in order to investigate possibilities of reducing costs by replacing tables with beds. Plant densities were higher than those recommended on conventional horticulture (9 plants/m2). Fertiliser application was conducted as recommended on tables through day-to-day application of solutions. Plate 5 summarising results obtained on tomatoes show that globally, beds covered with plastic as on tables gave good results with high yields (42 T/ha); however, uncovered beds (cheaper) give better results with bigger fruits, a longer harvest period and higher yields on tomatoes (58 tons/ha). Similar results were obtained on cucumber (>50 T/ha), cabbage and cauliflower (See plates below).

13

15 harvests, 64 g/fruit (40-89 g), 58 T/ha

Covered bed Aspect of a cluster Vegetative growth 1st harvest Yield data

Non covered bed Aspect of a cluster Vegetative growth 1st harvest Yield data

Plate 3: Compared effect of groundnut shells in dug beds (covered and non covered) on tomatoes

Plate 4: Compared effect of groundnut shells in dug beds on cabbages

Plate 5: Compared effect of groundnut shells in dug beds on various species

Effect of different substrates

Table 2 and plate 6 respectively present details on the 5 treatments (types of substrates) compared, including the standard one composed with groundnut shells, rice husks and gravels, and views of these substrates.

Trials were conducted based on experimental designs with replicated treatments enabling statistical analyses to check differences.Main results

Table 3 shows that the standard substrate (T1) and groundnut shells (T2) had the best effects on plant growth, In fact, all 5 treatments had a net effect on plant height but the main differences were linked to lateral growth or plant canopy. This is clearly illustrated in the figure below.

Table 3: Effects of substrates on plant growth

14

2-3 harvests, 450 -

500 g/head 45 (non

covered) to 50

(covered) T/ha

Cucumber :15 harvests

(40-50 T/ha);

Cauliflower: (3-5

harvests): 300-400

g/head, 30-40 T/ha

TreatmentsPlant final height

(Means in cm)Plant canopy (Means in cm)

T1 (Standard) 146.6a 325.3a

T2 (Groundnut) 143.2ab 314.9a

T3 (Rice husks) 149.5a 205.9b

T4 (Saw dust) 125b 99.1c

T5 (Mixture) 146a 119.3c

Means 142.1 212.9

As it relates to plant reproductive phase, it was observed that T1 and T2 were the earliest treatments in terms of flowering and fruiting. Table 4 comparing the effects of substrates on fruit number and net yields show the highest performances of T1 and T2 statistically equal to each other respectively with 19 and 17 fruits/plant (average yield = 9.6), 47 and 40 T/ha (average yield = 25.4 T/ha). This is illustrated by the attached figure and plate 7 linking net yield to fruit number with T1 and T2 (best plant growth) being the best treatments.

Table 4: Effects of substrates on yield and yield components

TreatmentsMean fruit

number/plantMean yield

(T/ha)

T1 (Standard) 19a 47.4 a

T2 (Groundnut) 17a 40.4 a

15

T1 T2 T3 T4 T5

72.1 71.5 53.6 44.5 53.3

125.7 124.8 127103.9 119.1

146.6 143.2 149.5125

146

325.3 314.9

205.9

99.1 119.3

Effect of substrates on plant growth

4 weeks 8 weeks12 weeks Lateral growth

T1 T2 T3 T4 T5

19 178

2 4

47.7 4958.4

41.3

53.847.4

40.4

23

4.312

Effect of different substrates on yield and yield components

Fruit number /plant weight/fruit (g)Net yield (T/ha)

T3 (Rice husks) 8b 23 b

T4 (Saw dust) 2c 4.3 c

T5 (Mixture) 4c 12 c

Means 9.6 25.4

Standard (T1) Groundnut (T2) Rice husks (T3) Saw (T4) Mixed (T5)

Plate 2: compared effects of different substrates on a tomato crop growth

5.2. Topic 2 : organic fertilizers (Full season)

Research results on organic fertilisers

Figure 2 provides details of the trial consisting of comparing 5 different fertiliser applications including the standard (imported inorganic fertiliser solutions) and 4 organic manures or mixtures locally available (goat/sheep and cow dung, poultry manure and a mixture of these).

Main results:

Tables 5 and 6 and their attached figures respectively present data on compared effects of different manures on plant growth through plant height and on earliness of flowering and fruiting. In all cases, the standard treatment (T1) and poultry manure (T4) were the best. The trial is being finalised and the analysed being performed.

Table 5: Effect of different organic fertilisers on plant growth

TreatmentsMean plant height (8 weeks, cm)

16

T1 T2 T3 T4 T5

28.8 20.1 14.726.4 21.3

59

36.322.4

48 40.7

88.9

53.632.5

70.8 62.9

97.9

59.638.2

84.570.4

129.8

90.8

62.6

11199.8

Effect of different manures on plant height (cm)

2 weeks 4 weeks6 weeks 8 weeks 12 weeks

T1 (Standard) 129.8a

T2 (Goat) 90.8b

T3 (Cow) 62.6c

T4 (Poultry) 111d

T5 (Mixed) 99.8e

Means 98.8

Table 6: Effect of different organic fertilisers on plant reproductive phase

Treatments Mean days

to floweringMean days to

fruiting

T1 T2 T3 T4 T5

3040.5

60

34.5 37

35

46.3

65

39.8 43

Effect of different manures on plant reproductive phase

50 % Flowering 50 % fruitingT1 (Standard) 30a 35

T2 (Goat) 41b 46

T3 (Cow) 60c 65

T4 (Poultry) 35d 40

T5 (Mixed) 37e 43

Means 40 46

Plate 6 and table 6 show details of plant vegetative and reproductive phases under the different treatments. The above mentioned best performance of T1 and T2 can clearly be seen as compared to other treatments.

This finding shows that potentially, there are chances of substitution possibilities of the imported fertiliser solutions by locally available organic matters, which will enable significantly reducing acquisition and production cost of the micro-gardening technology.

17

Standard (T1) Sheep/goat (T2) Cow dung (T3) Poultry (T4) Mixture (T5)

Standard (T1) Sheep/goat (T2) Cow dung (T3) Poultry (T4) Mixture (T5)

Plate 6: Compared views of plant growth and reproductive phase (same planting date) under as

linked to different manures (Treatments 1 and 4, the best are bordered in red)

Table 6: effect of different manures on fruit number and net yield

TreatmentsMean fruit

number/plantNet yield

(T/ha)

Check Sheep/Goat

Cow dung Poultry Mixed

21.75

5.8 4.059.6

5.43

44.85

17.38

9.73

26.85

14.63

Effect of manures on net yield (T/ha)

Frt num/pl Net yield (T/ha)T1 (Standard) 22a 44.9a

T2 (Goat) 6b 17.4bc

T3 (Cow) 4b 9.7b

T4 (Poultry) 10c 26.9c

T5 (Mixed) 5b 14.6b

Means 10 22.7

5.3. Topic 3 : Organic fertilizers during off-season

Plant vegetative growth:

18

Tables 7 and 8 show the high performance of the standard chemical fertiliser solutions (T1) followed by poultry manure (T3, 100% and 75% in mixture with groundnut shell powder) both on plant height and lateral growth (cm). The low performance of T2 (groundnut shell powder) seems to be linked to the poor quality of the manure.

Table 7: Plant height as influenced by treatments (12 weeks after planting)Treatments R1 R2 R3 R4 Means

T1 (Standard fertilisers) 82 74.7 86.3 84 82a

T2 (100% groundnut shells, GNS) 44.5 39 29 44 39b

T3 (100% poultry manure, PM) 65 69.3 63.7 74.7 68c

T4 (Mixture GNS-PM, 75-25) 70 59.7 69.7 65 66d

T5 (Mixture GNS-PM, 25-75) 79.3 70.3 68 71.3 72dc

Means 68.2 62.6 63.3 67.8 66

Means followed by the same letters are not significantly different at 5%.

Table 8: Plant lateral growth as influenced by treatments (12 weeks after planting)

Treatments R1 R2 R3 R4 Means

T1 (Standard fertilisers) 87 93 107 120 102a

T2 (100% groundnut shells, GNS) 44 0 15 25 21d

T3 (100% poultry manure, PM) 57 56 57 57 66bc

T4 (Mixture GNS-PM, 75-25) 56 74 50 48 57f

T5 (Mixture GNS-PM, 25-75) 82 41 51 51 56f

Means 65.2 52.8 56 60.2 59

Means followed by the same letters are not significantly different at 5%.

Figure 4 below shows the impact of plant vegetative growth through its 2 components: plant final height (12 weeks after transplanting) with T1, T5 and T3 having respective mean values of 82, 72 and 68 cm, and plant lateral growth which as in previous trials, has proven to make the difference in terms of correlation to net yield (102 cm for T1, 66 cm for T2 and 56 for T5)

19

T1 T2 T3 T4 T5

82

39

68 66 72

102

21

66 57 56

Figure 4: Effect of manure on plant vegetative growth

Plant height Lateral growth

Yield and yield components

The same trends can be observed in tables 7 and 8 with T1, T3 and T5 both for fruit number per table and net yield with respectively 40, 20 and 15 T/ha. Overall, the relatively lower yields compared to full season production can be understood given the adverse conditions of the rainy season. This result confirms the effectiveness of poultry manure alone (20T/ha) observed in our previous trials. Again, T2 (groundnut shell dust) has been so late in flowering due to its negative impact and heating up just after its application thus compromising plant evolution. It can be seen that the poorest treatment performances (T2 and T4) with low fruit number and weight are those containing groundnut shell dust. As stated above, in this case, the quality of the organic matter (status of decomposition) needs to be considered. These findings to be completed by costs considerations will be made available to beneficiaries.

Table 7: Fruit number per table as influenced by treatments

Treatments R1 R2 R3 R4 Means

T1 (Standard fertilisers) 68 121 79 97 91a

T2 (100% groundnut shells, GNS) 0 0 0 0 0c

T3 (100% poultry manure, PM) 54 33 32 34 38b

T4 (Mixture GNS-PM, 75-25) 8 7 5 1 5c

T5 (Mixture GNS-PM, 25-75) 39 41 36 43 40b

Means 33.8 40.4 30.4 35 40

Means followed by the same letters are not significantly different at 5%.

Table 8: Yield (T/ha) as influenced by treatments

20

Treatments R1 R2 R3 R4 Means

T1 (Standard fertilisers) 30 60 30 40 40a

T2 (100% groundnut shells, GNS) 0 0 0 0 0b

T3 (100% poultry manure, PM) 30 10 20 20 20c

T4 (Mixture GNS-PM, 75-25) 3 3 3 0 2d

T5 (Mixture GNS-PM, 25-75) 10 20 10 20 15c

means 14.6 18.6 12.6 16 16

Means followed by the same letters are not significantly different at 5%.

Figure 5 shows the respective yield performances as related to fruit number per table. As mentioned above, fruit number, fruit weight and plant lateral growth are key indicators of good yield.

T1 T2 T3 T4 T5

91

0

38

5

4040

020

215

Figure 5: Effect of manures on fruit number/plant and net yield

Fr. Number Yields (T/ha)

Plate 7 presents views of compared fruit formation for the different treatments.

T1 (standard fertilisers) T2 (100% GNS dust) T3 (100% Poultry manure)\

21

T4 (Mixture GNS-PM, 75-25) T5 (Mixture GNS-PM, 25-75)

Plate 8: A few pictures on the impact of treatments compared

Considerations on cost reduction

Table 9 below shows a breakdown of costs reduction by adopting any of the new versions. As a result, cost reduction goes from 11 to 536%.

Table 9: Breakdown of costs of the different micro garden versions

Versions Stand + substrate

Input costs

Production (kg/m2)

Total costs

% of cost reduction

Table -Conventional 300 50 3 to >5 350 -

Table-manure 300 15 3 315 11

Dug bed-conventional 40 50 3 to >5 90 289

Dug bed-manure 40 15 3 55 536

22

6. Conclusion

The action research component described above, carried out over the last 3 years in collaboration with the University of The Gambia had the overall goal of proposing accessible micro-gardening versions based on locally available inputs to target beneficiaries (urban and peri-urban communities).

The research work has enabled to come to the following conclusions:

Investigations on possibilities of simplifying the solid substrate consisting of a mixture of broken groundnut shells + rice husks + gravels, have statistically indicated that groundnut shells alone can replace this mixture with the same level of yield performance (40 and 47 T/ha respectively). This finding is important since it will help improve access to the technology through a simper substrate.

This result has been confirmed over the last 2 years and is the basis of the final phase of the GAMHORT project which targeted schools and other institutions where it has worked very well. In addition, the simplified substrate has been successfully used in dug beds with the same level of performance compared to tables (around 45-50 T/ha).

Research on possibilities of replacing the chemical fertilizers by locally available organic matters has proven the good performance of poultry manure in terms of impact on plant growth and reproductive phase and therefore, on yield, though lower compared to chemicals. In this case, 2 trials were conducted in different seasons (full and off seasons):

Investigations on local manures in full season:

The comparison of different local manures including poultry, cow, sheep/goat drops and a mixture of these manures, has clearly indicated that poultry manure is a potential alternative to chemical fertilizers with average yield levels of 27 T/ha compared to the general mean of 23 T; the chemical fertilizers have still been the highest with 45 T/ha.

Investigations on local manures in off-season:

The second trial on organic fertilizers conducted in hot and rainy season trying to build on previous findings, consisted of comparing poultry manure alone with groundnut shell dust and different combinations of both together with the standard chemical fertilizers, has shown that:

23

Groundnut shell dust if not well decomposed, has a negative impact on plant growth, reproductive phase and yield;

Yield levels in off-season are lower compared to full season with averages of 16 and 23 T/ha due to the more intense biotic and abiotic stresses;

Poultry manure is confirmed after chemical fertilizers with respective yield achievements of 20 and 40 T/ha.

Overview on cost reduction:

Further to the various trials conducted, lower cost versions have been worked out with varying levels of costs depending on the use of wood or not (tables vs.dug beds) and the type of fertilizers (Chemical or organic). As a result, considering the conventional version as a reference, cost estimates varied from 11% (tables with manure) to 536% (dug bed with manure).

This finding indicates that the 3 concepts initially targeted for the micro-garden technology (effectiveness, affordability and availability) needed to be in place in order to sustain the technology have been achieved.

24