The potential of ISFM in cocoa

There is an avenue to increase cocoa yields in West Africa through integrated soil fertility management (ISFM). This PhD project will explore the potential of several options of soil fertility management in cocoa farming. The project strives first to deepen our understanding of cocoa farming systems, focusing on the availability of organic resources and the effect of current and improved fertilization practices on yields. This will help to assess the relevance of technical options at hand for different categories of cocoa farmers. The effectiveness of mineral fertilization will further be assessed by identifying the key soil characteristics which limit the crop responsiveness to applied nutrients. Within the range of a prioriopportunities, cocoa husk recycling is attractive because of its high content of potassium (K). The temporal patterns of nutrient release from cocoa husk will be identified, and selected management options will be tested to avoid excessive leaching without increasing the risk of black pod disease spread. The project will also assess the role of organic matter (OM) in cocoa residue recycling in relation to the large amount of litter annually produced in mature plantations (5 t DM ha-1 on average). The outcomes will provide a better understanding of nutrient cycling and contribute to design improved soil fertility recommendations in cocoa plantations.