Pesticides use in cocoa sector in Cameroon: characterization of supply source, nature of actives ingredients, fashion and reasons for their utilization

The chemical control is the widely control method applied in Cameroon for pests and diseases by all the cocoa producers without technical suitable assistance by the State as before 1980’S. However, it is known that farmers have less knowledge on the good pesticides use for the control of a specific pest. The objective of this study was to provide insight in current pesticide use in the cocoa sector in Cameroon. A stratified sampling scheme was used. A total of 251 cocoa farmers, 20 post-harvest cocoa traders and 37 chemical retailers were randomly selected and interviewed. The study showed that 35 different chemicals were marketed in Cameroon for use in cocoa: 4 herbicides, 11 fungicides and 20 insecticides. Of 251 farmers consulted, 96.8% said that they use pesticides on their farms while 3.2% did not. Fungicides were used most often by farmers 61.8%) followed by insecticides (38.2%). Eight active ingredients although, officially banned, were still being used on cocoa farms. Over 77% of farmers do not respect the official spray recommendations for chemicals. Moreover, 64% do not respect recommended doses. Two main pesticide-supply-pathways exist in Cameroon: a legal and illegal supply chain, which provides 51% of pesticides to cocoa farmers, resulting in an estimated loss of value added tax for the Cameroonian government of about 550 000 to 2.4 million Euros per year. These results suggest that improved pests and diseases control by the State and raising farmer awareness about pesticide use in cocoa could greatly attribute to more sustainable cocoa economy in Cameroon.Keywords : Cocoa, pesticides, insecticides, fungicides, Cameroon

Biological control of cacao diseases

This chapter discusses the advances in biological control of cacao diseases over the last 15 years. Most attention has been focused on biological control of frosty pod rot (Moniliophthora roreri), witches' broom (Moniliophthora perniciosa) and black pod disease (Phytophthora spp.). Research on biocontrol of other diseases in the cacao phyllosphere or rhizosphere is scarce or in its infancy. There is, however, a steady increase in information regarding the factors influencing and the mechanisms underlying biological control of cacao diseases as well as practical aspects such as inoculum production, formulation and application. There has been a clear shift away from inundative approaches using epiphytic BCAs towards more classical biocontrol approaches using bacterial and fungal endophytes as well as vesicular arbuscular mycorrhiza. These have the advantage that they can permanently establish themselves in the cacao tree. Moreover, besides direct competition for space and nutrients, antibiosis and mycoparasitism, through induced resistance and growth promotion, endophytes have a larger arsenal of mechanisms through which they can help protect their host. Endophytic BCAs could thus provide more effective and sustainable disease control. Recent advances in our understanding of the mechanisms through which endophytic biocontrol agents can reduce pest and disease impact provide possibilities for innovative disease control strategies, including combination therapies together with natural or chemical products. Continued work on production, formulation and application is also necessary in order for biocontrol to become economically interesting. However, biological control will not become a stand-alone solution for disease control but should become part of integrated pest management strategies, with cultural management as a central and reinforcing pillar. (Résumé d'auteur