Management of Wild Pollinator Services in Cocoa (Theobroma Cacao L) Production Systems in Ghana

Abstract

Studies to evaluate farmer knowledge of cocoa pollination, farm practices and their impact on cocoa pollination were conducted through questionnaires and field experiments in three major cocoa growing areas in Ghana from 2007 to 2009. Results show that cocoa farmers were unaware of the concept of pollination, identity and ecology of cocoa pollinators, hence have not intentionally developed practices to enhance pollinator services in their farms. Proximity of cocoa farms to natural forests did not influence the abundance of cocoa pollinating ceratopogonid midges as well as pod set of cocoa. Ceratopogonid abundance, however, significantly differed (p<0.05) under varying cocoa canopies, shade cover levels and presence of plantain/banana trees in or near farms. Farms treated with aqueous neem seed extract (ANSE) recorded more ceratopogonids than with confidor (Imidacloprid) 2 and 60 – 120 days after spraying insecticides (DASI). Ceratopogonids population appeared to recover within 30 DASI. Pod set was also significantly higher in farms treated with ANSE than those treated with confidor 30 and 60 – 120 DASI. Mud-wall breeding troughs with pod husk, plantain stem and pod husk/plantain stem mixture as breeding substrates increased cocoa pod set in the dry season. All three sampling methods used (UV-bright painted pan traps (UVPPT), McPhail traps and motorized aspirators) were effective for sampling ceratopogonids, the yellow UVPPT being the most efficient. The stingless bee, Liotrigona parvula Darchen was collected on cocoa flowers for the first time.