Abstract
Agronomic research in cacao in the 1950s in Jamaica was devoted almost entirely to the introduction, propagation and establishment of different varieties imported mainly from Trinidad and St Vincent. Field evaluation of these introductions led to the adoption of a few medium- to high-yielding varieties, but the later discovery of their susceptibility to black pod disease [Phytophthora palmivora (Butl.) Butl.] restricted their use as parents in breeding programmes. The resulting germplasm base of the cocoa industry is very narrow. However, the observed slow growth of the pathogen in the pod tissues of the susceptible variety ICS 60 permitted its use and resulted in the production of PA 150 × ICS 60 as the best-yielding local hybrid. Nutrition experiments dealt mainly with the effects of N, P and K on yield of cocoa cultivated with or without shade, and with liming of acid soils, but no experimentally-determined fertilizer recommendations ensued. New fertilizer experiments aim to address this, and other current research seeks to broaden the germplasm base of the cocoa industry and to re-evaluate a cocoa/coconut intercropping system.