Honey bees bring more cashfrom cashewKwame S Aidoo1

Mary Adzanyo2

Rita Weidinger2

Andre M Tandjiekporv

Keywords: Apis mellifera adansonii,bee products, Benin, crop yield,Ghana, integration, top-bar hive

The integration of beekeepinginto cashew orchards has greatpotential to increase cashew nutyields and to also improve farmers'income through the sale of beeproducts. Facts and figures forthe benefits of this integrationare not available in cashewproducing countries. To measurethe contribution of bee pollinationfor increasing yield and quality ofcashew nuts, The African CashewInitiative commissioned this studybetween October 2012 and June2013. We introduced honey beecolonies into cashew farms in Beninand Ghana to find the effect oncashew production.

Materials and methodsThe study took place in the cashewgrowing belts of Benin and Ghana.In Ghana, two experimental farmswere set up in each of four cashewgrowing communities: Badu,Kranka,Tanobuase andWenchi.

Cashew fruits with the mature nut (which is the seed)

In Benin, farms were selectedin Bassila, Ouesse, Parakou andTchaourou - a total of eight farms.Within each community, two farmswith trees of a similar age, goodcultural practice, and spaced notless than 2 km apart were used. Thestudy began in October 2012, whencashew trees in both countries hadjust started flowering.

Two honey bee colonies(Apis mellifera adansonif) in top-bar

One of the experimental hives overflowing with bees and stores

hives were set close to a markedexperimental plot on the first farm.Seventy cashew trees (seven rows,ten in each row) were marked withred paint to form the experimentalplot of the orchard. The hives wereinspected internally and bathroomscales were used to record theirinitial weight. The second farm(control) was selected at a distancenot less than 2 km away from thefirst and without managed honeybee colonies. Seventy trees weresimilarly marked with red paint.

Data collectionFour beekeeper-cashew farmers,in most cases owners of theexperimental farms, were informedabout the study after they agreedto fully support the research.Notebooks marked up with therelevant tables for data collectionwere explained to the farmers andthey used them for record keeping.The farmers were taught to carryout the following:Accurate scale reading; Weighinghives weekly and recordingtheir weight accurately; Weeklycollection, weighing and recordingof cashew nut yields from the70 trees; Weekly sampling,weighing and recording the weightof 200 nuts from the total obtainedfrom the 70 trees.

Questionnaires andinterviewsEighty cashew farmers in Ghanaand 40 in Benin were interviewedindividually and taken through astructured questionnaire. Theirresponses were recorded andanalysed using the statisticalsoftware SPSS 16.0 for Windows.

Results - findings frominterviewsCrop and animal integrationGhana - the majority of farmers(88%) did not grow any cropsunder the closed canopy of theirorchards and 38% could not thinkof any crops that could be grownunder cashew trees for additionalincome.The remaining 12%cultivate one or more of avocado,cocoa, cocoyam, ginger, plantainand yam under the trees. Mostfarmers did not keep animalson their farms although a smallnumber (26.3%) kept bees, hens,sheep or snails.

Benin - none of the farms had anycrops growing as undergrowth, and

Weighing a hive using a modified bathroom scale

none of the farmers could think ofa crop that could be cultivated forextra income. It was observed thatthe spice Aframomum melegueta(also known as Guinea pepper)was growing wild in the forestvegetation adjourning cashew

Table 1. Summary of questionnaire responses from 80 farmers inGhana and 40 in Benin

Parameter/Indicator

Males interviewedFemales interviewedAgro-chemical use on farmsCashew farm intercropped with other crops forextra incomeFarmers keeping animals on farmsFarmers keeping bees on farmsOf farmer beekeepers, those in Ghana with1-20 hives, or in Benin with 6-20Beekeepers with basic beekeeping equipmentFarmers joining beekeeping associationsBeekeepers processing honey using crush anddrain methodBeekeepers' total annual honey harvest (Ghana:6-80 kg; Benin: 5-50 kg)Beekeepers with hive productivity kg of honey/hive/year (Ghana 7-21; Benin 7-14)Beekeepers processing empty, broken combs intobeeswaxAvailability of beekeeping extension services

Ghana(%)

78.821.2<10

12.026.317.1

69.062.521.0

80.0

80.0

80.0

40

0.0

Benin(%)

92.517.5<20

0.00.0

57.5

65.040.080.0

76.2

70.0

70.0

31.60.0

Farmers with annual nut production of 100-4,000 kg(Ghana) and 100-3,500 kg (Benin) 89.7 94.7

Farmers drying raw cashew nuts for 1-3 daysFarmers processing cashew apple

89.73.8

94.713.2

orchards. Its integration into theorchards could be explored. Onlythree farmers kept cattle and hens,however over 55% of cashewfarmers interviewed kept bees ontheir farms.

Agrochemical usage: Almost allthe farmers (90% in Ghana; 80%in Benin) did not use chemicalpesticides or fertilisers on theirfarms. Oecophylla red ants werewidespread in both countries andused as biological agents for pestcontrol on cashew orchards - seeTable 1.

Integration of beekeepinginto cashew orchardsAverage honey harvests per colony,per season were 20.7 kg (Ghana)and 13.7 kg (Benin).There is a similar trend forbeeswax: 1.40 kg for Ghana and0.92 kg per colony for Benin.Propolis production was also higherfor colonies in Ghana than in Benin(0.37 kg and 0.26 kg respectively) -see Table 2.

EffectsTable 3 shows the results ofeffective pollination activitiesof honey bee colonies in theexperimental orchards. Onaverage, the yield of raw cashewnuts (RCN) was 9.1 kg/tree and4.2 kg/tree for orchards with andwithout bee colonies respectivelyin Ghana; and 6.75 kg/tree and 2.16kg/tree in Benin. The indication isthat the presence of honey bees inorchards improves RCN yields to

Table 2. Honey, beeswax and propolis production for cashew orchardsin Ghana and Benin

Colony Honey (kg) Beeswax (kg) Propolis (kg)Number Ghana Benin Ghana Benin Ghana Benin12345

678Total

23.50

35.500.00

10.5035.50 +

15.000.0016.58.50

145.00Mean 20.70

Range 8.50-35.50

4.200.00

28.80

11.20

1.602.400.000.70

7.50 2.40 +1.01

6.5013.90

0.001.10

24.10 O.S796.20

13.704.20-28.80

9.781.40

0.57-1.60

0.280.001.930.750.50

0.440.931.626.450.92

0.28-1.93

0.30 0.000.400.000.25

0.000.200.20

0.45 + ' 0.250.000.400.350.45

0.300.300.30

2.60 1 1.550.37 0.26

0.25-45.00

0.20-0.30

NotesHarvest was stolen and hive burntColony abscondedTwo harvests carried out inWenchi

Table 3. Raw cashew nut yields

PlotNumber

1

2

3

4

Total

Mean

With beecolonies(kg/tree)

11.3012.106.966.00

36.36

9.1

GhanaNo bee

colonies(kg/tree)

5.203.803.993.90

16.894.2

% yieldincrease

117.3218.4

74.475.0

116.7

With beecolonies(kg/tree)

13.807.012.303.90

27.016.75

Benin

No beecolonies(kg/tree)

3.153.100.801.608.65

2.2

% yieldincrease

337.0

126.3182.5144.6"

212.5

Figure 1. Raw cashew nut yields in cashew orchards in Ghana with andwithout honey bee colonies (2012/2013 season)

14

12

10

With bees

Without bees

Kranka Tanobuase Wenchi Badu

up to 116.7% in Ghana and 212.5%in Benin (Table 3; Figures 1 and 2).

Cashew nut qualityThe presence of honey beecolonies in orchards did notaffect RCN quality significantly asmeasured by the weight of 200 nutssampled in the same growing area(Figures 3 and 4).

Discussion and conclusionThe study has established thatthe incorporation of beekeepinginto cashew farming systems willimprove the productivity of farmsand income levels of farmers intwo ways: the sale of bee products(beeswax, honey and propolis)and also increased nut yields asa result of effective pollinationactivities of honey bees. Thebaseline rate of incorporation hasbeen established as two coloniesper hectare of orchard- This meansthat a cashew farmer with a fivehectare orchard could operate anapiary of ten honey bee colonies.However this number could beincreased gradually dependingon the availability and richnessof additional forage resourceswithin the cashew ecosystem andthe presence of nearby apiaries.It was observed during the studythat worker honey bees sometimescollect cashew apple juice. Itmust be noted that honey beesdo not depend entirely on thecashew trees for forage. Otherflowering plants in the nearbyvegetation provide additionalforage especially during the off-flowering period of the cashewtrees (June to October): these extrasources sustain bee colonies in thecashew ecosystem. Honey beesare not the only bee pollinatorsof cashew flowers, however largenumbers of honey bee workers onthe farm (over 70,000 from the twocolonies for one hectare) ensuredthat every receptive hermaphroditeflower was visited and fertilised toproduce fruits. A single cashew treeat one time produces about767 flower panicles of which63-67 are hermaphrodite (maleand female structures in one) and250^400 are male flowers. All thehermaphrodite flowers must bevisited by pollinators to effectfertilisation for fruit set (Bigger,1960). Several other bee speciesincluding stingless bees and smallsolitary bees also contribute to

Figure 2. Raw cashew nut yields in cashew orchards in Benin with andwithout honey bee colonies (2012/2013 season)

o•aOJ

33o

16

With bees

Ousse Tchaourou Parakou Bassila

the effective pollination of cashewflowers.Studies conducted in severalcashew producing countries suchas Brazil and India have attributedlow nut yields of orchards toinadequate pollination. Thenotable significant higher RCNyields recorded in farms withhoney bee colonies are in linewith other studies conducted inIndia. Reddi (1987) found that25-72% of cashew flowers werenot pollinated in nature becauseof pollinator limitation and statedthat an increase of 157.8% waspossible if flowers receivedadequate pollen. The significanthigher yields recorded on farmsin Ghana over Benin are attributedto low species numbers of otherbees recorded in orchards in

Women harvesting cashew nuts on a farm in Ghana

Table 4. Income value of integrating two honey bee colonies into one hectare cashew farms in Ghana and Benin

Item

RCN Increased

RCN yield per tree

Total RCNyield/ha/ year

Total value hiveproducts(two hives/ha/year)

Total gross annualincome

Exchange rate (2013)

Ghana without beecolonies

4.5 kg/tree

336 kg value at GHC336.00

0

GHC 336.00US$ 176.84

US$1. 00 = CMC 1.90

Ghana with beecolonies102.2%

9. 1 kg/tree679.4 kg value atGHC 679.40

GHC 396.20US$208.53

GHC 1075.60US$566.11

Benin without beecolonies

2. 16 kg/tree

175 kg value at CFA70,000.00

0

CFA 70,000.00US$ 140.00

US$ 1.00 = CFA 500.00

Benin with beecolonies212.5%

6.75 kg/tree

546.9 kg value atCFA 218,760.00

CFA 69, 220.00US$ 138.40

CFA 287,980.00US$ 575.96

Figure 3. RCN quality as determined by weight of 200 RCNs inorchards with and without honey bee colonies in Benin(2012/2013 season)

Ousse Tchaourou Parakou Basilla

Figure 4. RCN quality as determined by weight of 200 RCNs in orchardswith and without honey bee colonies in Ghana (2012/2013 season)

With bees

Without bees

Kranka Tanobuase Wenchi Badu

the cashew belt of Benin. Manystingless bees that were found inorchards in Ghana were absentin Benin. An enterprising farmercould additionally cultivateshade loving crops (for exampleAframomum melegueta and ginger)under the cashew trees to improvefarm income. Domestic animalsincluding goats, poultry and sheepon the farm will also add to familywealth and health.

Beekeepers in both countries needmore knowledge concerning themanagement of apiaries, especiallyin the cashew production system.Current methods of harvesting andprocessing of o^iality bee productsmust be also upgraded.

ReferencesBIGGER,M. (1960) Selenothripsrubrocinctus Giard and the floralbiology of cashew in Tangayika.East Africa Agricultural Journal.25:229-234.REDDI.E.U.B. (1987) Under-pollination: a major constraint ofcashew nut production. ProceedingsIndian National Science Academy.B 53: 249-51.

Acknowle dgmentsThanks to GiZ/African CashewInitiative (ACi) for providing thefunds for the research work. Theimmense support during the fieldwork provided by Messrs KodjoSiaka of Centre de RecherchesAgricoles (Benin), also H Odoi andE Laryae of ACi (Ghana) is muchappreciated.

Author details'Global Pollination Project-Ghana,University of Cape Coast,Cape Coast, Ghana

3African Cashew Initiative, Accra,Ghana