Cocoa floral phenology and pollin ation: Implications for productivity in Caribbean Islands

Abstract

Cocoa midges [Forcipomyia sp (Diptera: Cerato-pogonidae)] are major pollinators of cocoa and it is assumed that the number of fertilized pods and the increase in bean numbers may be the approach to enhancing cocoa yield. An insect survey using suction traps was employed to estimate the midge population dynamics in three Caribbean territories. Separate studies were conducted on the cocoa floral and reproductive phenology in addition to the evaluation of several naturally occurring substrates. The results indicated that the insect population as determined by the suction traps were low (27.1 ± 3.37 to 53.5 ± 8.47 transect site). The trees maintained the floral prolificacy even though the pollination [%] was low for Jamaica (0.91), Trinidad (0.88), and Tobago (0.11). However, it was improved when the midge pollinator population was increased with augmentation of substrates of cacao pods [5660] and banana pseudo-stem (1885). This resulted in significant increases in new pods which increased from < 10 pods/tree in the untreated areas to 49 to 76 pods/tree with substrate augmentation. It was evident that the discarded cocoa pod after harvest was a suitable feeding substrate and breeding site for the midge. This information is to be used to advance further studies in plant-pheromones which can serve as attractants to increase pollination/fertilization in cocoa. Key words: Theobroma cacao, cocoa midges, substrate augmentation, pollinators, floral phenology.