COCOACOCOA• Thoebroma cacao Family Sterculiaceae

• Economic Importance to Ghana

• Known in Ghana as the golden pod

• Production Between 1957 and 1966,

• 300,000 metric tons per annum valued at about #3,000,000,000.00,

• Making Ghana the leading producer of cocoa in the

world.

Economic importance of cocoaEconomic importance of cocoa • Revenue from cocoa was used to provide

• Free education,

• Free medicare

• Subsidy for housing and transport

• Road network Ghana from 1957 to 1966

• Population of 6 million people

How cocoa came and became How cocoa came and became successful in Ghana.successful in Ghana.

• Origin : Amazon forests on the slopes of Andies in South America (Brazil) and Central America.

• It grows as a small under storey tree, under tall big trees in the Amazon forest.

• Natives call it food for the gods (Theobroma)

SpreadSpread

• Spanish (colonialists) (conquistadors) found that the S/A natives prepared a festive food from dried roasted and fried cocoa beans, maize and pepper.

• This native food was bitter to the Spaniards. The Spaniards substituted milk and sugar for maize and pepper and produced chocolate.

• There was a crave for the product in Europe and chocolate business was developed.

• Raw materials needed to support the chocolate business.

• Spaniards and other Europeans attempted to grow

the crop in Europe, but the winter weather did not permit the cultivation of cocoa in the cold European climate.

• So the crop was taken to their tropical colonies.

• From S/A the Spaniards took cocoa to Fernando Po now Cape Verde Islands.

• From Cape Verde, Tetteh Quarshie brought cocoa to Ghana in 1879

Types of CocoaTypes of Cocoa

Cocoa color of color of no of seeds cotyledon podType unripe pods ripe pods per pod color surface

Criollo green or yellow 25 white rough red red warty

bottleneck curved beak

(Criollos produce fine cocoa but non commercial because of disease susceptibilty)

Forastero green yellow 40-60 purple smooth

Trinitario Hybrid between criollos and forasteros. Combine the two characters of criollos and forasteros

Subtypes of Forastero cocoaSubtypes of Forastero cocoa1. Upper Amazon Forastero• Self Incompatible, vigorous, some with resistant or

tolerance to black pod, and swollen shoot virus disease

• Eg. Nanays (Na), Parinaris(P) Scavinas (Sca), Iquitos (IMC)

2. Lower Amazon ForasteroSelf compatible, uniform bean size and slow growing, intolerant to full exposure, sensitve to swollen shoot virus diseaseeg Amelonado (Tete Quarshie cocoa)

The success of Amelonado in GhanaThe success of Amelonado in Ghana

1. Absence of Witches broom (Crinipellis perniciosa) and seed rot (Monilia roreri ) diseases in W/A

2. Lower incidence of blackpod disease in W/A compared to S/A

3. Amelonado is self fertile- No barrier to fruit set after pollination. Farmers could plant unselected seeds obtained from from nearby farmers.

3.Farming system • The slash and burn shifting cultivation practiced by

W/A farmers left tall forest trees to provide the permanent shade required for the crop.

• Temporary food inter-crops of plantain and cocoyam provided the temporal shade for the young seedlings.

4.Soil type• Abundant soil organic in the virgin forest in those

years supported the growth of Amelonado, which reached full bearing after 8-10 years.

5. Processing• Fermentation and Drying

• The small heap fermentation system practiced by the W/A farmer was ideal to produce good well fermented cocoa beans

• The dry weather from mid-November to January provided ideal weather for fermentation and drying of cocoa beans.

• The uniform bean size of 1gm, the unique flavor after fermentation favored processing into chocolate products.

6. Socio-economic factors

• Well organized market for purchasing dried cocoa beans.

• Social Factors ( money for Christmas and end of year celebrations)

• Prestige of a cocoa farmer ( farms as security for loans)

• Farmers’ adequately motivated.

Basic Ecophysiology of Cocoa.Basic Ecophysiology of Cocoa.The seed:• The seed has no dormancy.

• Seeds become fully mature before pods become ripe.

• Therefore seeds from semi ripe pods can be used for planting, but for fermentation and processing, seeds must be harvested from ripe pods.

• Seeds may germinate in unharvested overripe pods.

• Seeds lose their viability very quickly on exposure. For cultivation, fresh seeds from ripe pods are used. Seeds germinate in overripe pods.

• Seeds are killed after 8 minutes at 40C ( intolerant to clod)

• Can be stored in Charcoal powder or sawdust at 30% moisture after sweatings are removed for 10-13 weeks

• Removal of seed coat enhances germination

Seedling Growth:• Young seedlings require some shade for growth.

• Seedlings vary greatly in their shade requirements.

Lower Amazon forasteros are intolerant to full exposure. Upper Amazon types like “scavinas” tolerant to full exposure

• The seedling growth is orthotropic: with 3/8 phyllotaxy. After 1-3 years the terminal bud of the seedling divide to form 3-5 lateral branches called fans with ½ phyllotaxy. The process is called jorqueting.

• The point of branching is called jorquette.

• Just below the jorquette, a lateral bud shoots up to continue the upward growth of the seedling. Growth is thus in tiers (steps).

• Flowering starts soon after the first jorquette.

• The main stem is called chupon. Height of cocoa is regulated by pruning chupons or fans.

Growth of the adult treeGrowth of the adult tree• Adult tree grows in flushes.

• Terminal buds on young branches produce shoots simultaneously in response to rainfall and soil moisture conditions especially after period of drought.

• Mature tree is deciduous shedding old leaves during the dry season. Massive leaf litter could be found under cocoa plantations.

FloweringFlowering

• Flowers are formed on the main trunk and on the branches. This phenomenon is cauliflorous. The flowers are perfect and pentamerous.

• ie. Calyx - 5• Corolla - 5• Staminodes - 5• Stamens - 5

• Ovary with 5 Sepals: Sepals fuse to form the pod.

Incompatibility:

• Unique, hormorphic, mulliallitic, sproplytically controlled.

• S1>S2=S3>S4>S5>S6 after pollination.

• Pollen tube grows but pollen nuclei unable to effect fertilization.

Significance of incompatibility on cocoa productionSignificance of incompatibility on cocoa production S1>S2=S3>S4>S5>S6 Genotype Progeny Fruit set and crossS1S2xS1S2 S1S1+S1S2 nil S2S1+S2S2

S1S2xS3S4 S1S3+S1S4 S2S3+S2S4 high

S1S3XS1S4 nil nil

S2S3XS2S4 S2S2+S2S4 S2S3+S3S4 50% ovule abortion

no fruit set S2S3XS1S4 S1S2+S2S4 S1S3 +S3S4 high

S1S3XS2S3 S1S2+S1S3

S2S3+ S3S3 50% ovule abortion, no fruit set

Basic ecophysiology ctdBasic ecophysiology ctd• Cushions: Compressed branches on stem from where

flowers arise.• Pollination: Midges and Pysillides

• Cherelles: Young fruits below six weeks after pollination

• Cherelle wilt: Dropping of young cherelles. Physiological trimming mechanism to prevent over-bearing.

• Pods: Mature after 5 months attached to the cushion by the fruit stalk.

•

Basic AgronomyBasic Agronomy• Agronomic/Cultural Past Present• Practices• Land preparation Slash/burn Same• Shifting Cultivation• Planting material Amelonado Improved

hybrid

• Planting Stake, 2-4 seeds/hole, Stake,• April/May, June Seedlings raised

in nursery in June

• Spacing Irregular 8x8, 10x10

• Intercrops Plantain/Cocoyam Same

• Permanent shade Forest trees Fast growing• Leguminous

trees• Pruning Irregular Irregular

• Recommendation Removal of basal fans, when 2nd chupon is formed

• Stop growth at 2nd jorquette• to shape trees• Fertilization Nil P205, Mg and K.

• Harvesting Nov- Jan 2 weeks regular• harvesting to

control black pod

• disease and quality • of seed•

Effects of shade and fertilizer on cocoa Effects of shade and fertilizer on cocoa productionproduction

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Fermentation and quality of cocoaFermentation and quality of cocoa

• During fermentation• Mucilaginous sugary sweatings acted on by yeast and

converted to alcohol

• The process leads to rise in temperature

• Aerobic phase: alcohol converted to acetic acid and carbon dioxide by acetone bacterial

• Bean color changes to purple brown due to enzyme action on the anthocinines

• Chocolate flavor and aroma develope

Types of Fermentation SystemsTypes of Fermentation Systems1. The small heaps on banana leaves practice by

Ghanaian farmers 2. Tray fermentation developed at CRIG - tray size 1mx1.5mx10cm - Base of trays slated with palm fronds or net and

then staked together and covered with sacks.

3. Box fermentation- Box sizes about 2m x1.5m x1m with drainage holes

-boxes arranged in 3 tiers. Beans loaded into the middle box from the top after two days and then to the bottom box after the next two days. Fermentation is completed after the next 2 days

Cocoa qualityCocoa quality• Determined by undesirable types including

• Slaty beans as a result of improper fermentation

• Mouldy beans due to black pod disease

• Flat beans due to incompatibility factors

• Germinated beans due to over- ripeness

• Placenta due to negligence

• Acid cocoa due to genotype and large heap fermentation

Challenges posed by the Swollen Shoot diseaseChallenges posed by the Swollen Shoot disease

• CSSV - viral disease

Transmitted by mealybugs

- Virus endemic in forest trees

e.g. Cola chlamydanta , Bombax spp

by 1948, 38,000,000 trees removed.

The only control measure is to cut out diseased and contact trees.

• Cocoa Research Institute of Ghana was established to find solutions.

• Possnette visit to Trinidad.

(1) 100 upper Amazon pods ( prefix T)

4,000 plants grown from the 100 pods

• Six selections T79

T85

T63

TT65

(2) Cross with Amelenado – Tafo Hybrids

Cocoa Seed GardensCocoa Seed Gardens

• Cloning self incompatible parents

• Biclonal seed gardens

• Monoclonal seed gardens

FutureFuture

• Black pod disease

• Resistance to P. megacarya and P. pamivora

• Tolerant to CSSV disease exposure

• Tolerant to exposure (establishment under no shade conditions)

• Yield

Permanent shade typesPermanent shade typesCocoa/Tree Crop

• Cocoa/Mango

• Cocoa/Oil palm

• Cocoa/Coconut

• Cocoa/Rubber

• High density plantings

(3) Inter Amazon Crosses

T85XT79

T85XT63

(4) Search for New Introductions and further Inter-Amazon crosses

Eg.

T85XPA7

T85XSCA6

Time Scale Producing New HybridsTime Scale Producing New Hybrids

• Introduction - 10 years

• Progeny Testing - 10 years

• Seed Gardens and

Release of varieties - 5 years