5. Harvesting and Storage

Harvesting Cocoa Beans:

Farmers use long-handled knives or big machetes to harvest the ripe cocoa pods. The pods are ripe when they turn into a deep yellow color (for most of the varieties).

Figure 1: Harvesting tools

They are collected and then broken up with wooden tools. The beans inside are removed by hand. The shell is discarded and the wet beans are fermented for a number of days. This step is important for the development of the flavor. For the fermentation, the beans are placed in wooden boxes on the farm.
After fermentation, the beans are carried to the villages. There, they are dried on concrete floors for 7-10 days.
The speed of drying is very important. If the beans are dried too fast, they can develop acidic flavors. This is because when dried too fast, it is possible that the cotelydons do not dry completely and only the outer shell dries. After a few days, funghi can grow on the beans.
Sun drying usually provides optimal conditions. Sun and wind combined most of the times ensure adequate drying conditions.

Figure 2: Drying the beans

Storage of Cocoa Beans: 

Optimal storage conditions for cocoa beans include the following aspects:
1. The warehouse should not have cracks or holes in the walls to prevent insects from coming inside. Furthermore, they should have non-inflammable cement walls.
2.The floor level should be higher than the surrounding areas to prevent flooding.
3.The roof should be well-sealed and insulated, but not made of wood.
4.Adequate ventilation should be installed to prevent the development of molds.
5.The bags of beans shoud be stored on pallets, so that the bottom layer has air ventilation as well. The top layer of bags sould be at least 5-10cm away from the ceiling. Also to allow air ventilation.
6.The cocoa beans should be regularly inspected to prevent contaminations.
7.No other products should be stored next to the cocoa beans to avoid contamination.
8.The access to the storage area should be monitored and recorded.

Figure 3: Storage of Cocoa Beans

References

International Cocoa Organization. (2011). Factors to consider in the storage area in order to minimize risk. Retrieved 10 2018, from https://www.icco.org/faq/60-storing-cocoa-beans/107-factors-to-consider-in-the-storage-area-in-order-to-minimize-risk.html

Worldagroforestry.org. (n.d.). An Overview of Cocoa Production in Côte d'Ivoire and Ghana. Retrieved 10 2018, from http://www.worldagroforestry.org/treesandmarkets/inaforesta/documents/Cocoa_production_in_Cote_divoire.doc

Pictures:

Figure 1: http://www.cotterell.de/pictures/446/show/540x405/crop/VHW+05.jpg?sh=318e90c1f6dae3c8

Figure 2: https://d2v9y0dukr6mq2.cloudfront.net/video/thumbnail/Hb2xLftlindb3lr9/man-drying-cocoa-beans-in-tabasco-mexico_rrjujyh8g_thumbnail-full01.png

Figure 3: https://www.thechicagocouncil.org/sites/default/files/cocoa_crisis_main-77612127-900x600.jpg

 

4. Plant Improvement

Pollination: 

The cocoa plant is self-compatible and self-incompatible at the same time. That means it can perform both self-pollination and cross-pollination.
Self-pollination means that a plant has the ability to fertilize itsself. These plants have complete flowers including stamen and pistils. This can happen within the same flower or between two flowers on the same plant whereas cross-pollination requires two individual plants. The pollen from one plant fertilizes the ovule on the second plant.
The genotype of Theobroma Cacao is diploid (2n=20).

Figure 1

Plant Breeding and Plant Improvement:  

Grafting:
Grafting is one method how cocoa plants are propagated. Grafting is the process of placing on part of a plant on or into a root, stem or branch of another plant (britannica). In cocoa, a part of elite plant material (scion) is grafted on seedlings or already mature trees (rootstock). Grafting is done to imrpove disease resistance, ensure flowering and many more characteristics of the plants.





Breeding:
The aim of breeding cocoa plants has been focussing on yield and disease resistance for years. By crossing the three types Criollo, Forastero and the hybrid Trinitario some major progress has been achieved. However, since the cocoa trees are still very susceptible to certain pest and diseases, like for example the swollen shoot virus in West Africa, further successful breeding methods need to be developed.

In the Ivory Coast, plant breeding and biotechnological projects have been established in 40 programs concerning all kinds of crops. Cocoa is one of the main crops in these programs. The breeding focusses on qualitative traits, favourable environments and biotic stress.
However, breeding facilities lack adequate equipment and laborartors infrastructure. That is the reason why advanced breeding techniques are very hard to implement. The lack of educated and trained plant breeders is also hindering the progress in breeding techniques. Additionally, the acces to public or private national genetic resources is limited.

References

Diby, L., Kouame, C., Kahia, J. W., & Betemariam, E. (2017). Tea, Coffee, and Cocoa. Retrieved 10 2018, from https://www.researchgate.net/publication/308792482_Tea_Coffee_and_Cocoa

ENCYCLOPÆDIA BRITANNICA. (2018). Graft, Horticulture. Retrieved 10 2018

Koffi, K. (2008). Plant breeding programs in Cote d’Ivoire. Retrieved 10 2018, from FAO: http://www.fao.org/in-action/plant-breeding/our-partners/africa/cote-divoire/en/

Sheaffer, C. S., & Moncada, K. M. (2012). Introduction to Agronomy. Delmar Cengage Learning.

Pictures:

Figure 1: https://content.ces.ncsu.edu/media/images/ag396-19.gif

3. Pests and Pest management

Plantations in West Africa have several pests and diseases that are prone to affect the Cocoa plants.
Two insects that affect the cocoa trees very often are Mirids (Distantiella theobrama or Sahlbergella singularis) and so called stink bugs (Bathycoelia thalassina).

Figure 1: Mirid

Figure 2: Stink bug

Figure 3: Damage after punctures

An infestation with either of these two insects has severe consequences for the trees. They feed and inject their saliva into the plant leaves. The resulting punctures in the plant tissue make it possible for fungal pathogens to enter. This so-called "secondary invasion" results in dieback disease. Additionally, stink bugs causes premature ripening and also often deformations of the cocoa fruits.

The main pest management practice against Mirids is the application of insecticides. Stink bugs can also be controlled through this indirectly.
There has been very little research on breeding cocoa varities that are resistant against those two pests.

Starting in 1940, insecticides like endrin, heptachlor, lindane and dieldrin were sprayed on the cocoa plantations in West Africa. However, the insecticides were not used in the correct manner. Either they were sprayed prophylatically or when it was already too late and the plants were infected.
Since 2000, major developments have been introduced to the pest control of cocoa trees. There has been a lot of research and monitoring of the two most important pests, mirids and stink bugs. Additionally, the concerns about protecting the natural environment and the wildlife became more influential in pest management.
Major issues in the spraying of insecticides are that pest populations are very hard to predict, therefore it is difficult to say when thy have to be applied. Secondly, most farmers do not have the ability to spray large areas at short notice. That means it could already be too late for the application of insecticides.
Another very important concern when sprayng insecticides are the effects on the natural environment and animals .
Lastly, most of the farmers are smallholder farmers that simply cannot afford the chemicals or the needed equipment for a safe spraying of insecticides.

Another possible pest management practice is the use of aggregation pheromones. They are hormones which effect and confuse the insects in their mating behaviour. However, this method is not very established yet and needs further research.

Clearly, the pest management sector in West Africa still needs to develop further. More research about alternative practices such as pruning, agro-forestry, etc. has to be implemented. Furthermore, breeding and finding resistant cocoa varieties have to be emphasized.

Well-planned integrated pest management would include the use of resistant varieties, pheromones, alternative cultural practices and the use of chemicals when necessary. As already mentioned, this sector needs more research in order to establish best management practices for the crops, the people, as well as the natural environment.

References

Dropdata. (n.d.). The World's Worst Cocoa Problems. Retrieved 09 2018, from http://www.dropdata.org/cocoa/cocoa_prob.htm

Richard Adu-Acheampong1*, J. E. (2015). Strategy for Insect Pest Control in Cocoa. American Journal of Experimental Agriculture. Retrieved 09 2018

Skillman, V. (2016). Damage caused by Mirids. Retrieved 09 2018, from http://skillmav.wixsite.com/cocoapest/damage

pictures:

Figure 1: http://skillmav.wixsite.com/cocoapest/general-description

Figure 2: http://www.dropdata.org/cocoa/cocoa_prob.htm

Figure 3: http://gsbpestcontrol.com/img/cms/stink-bug.jpg