The impact of soil treatments on black pod rot (caused by Phytophthora megakarya) of cacao in Cameroon

This study was undertaken under farmers’ field condition in the Centre region of Cameroon. Trichoderma asperellum PRR11, together with a water and fungicide (Ridomil Gold 66 WP) control, were applied on a three weeks basis over two consecutive production seasons. Weekly data collection consisted of counting healthy and diseased pods. For each treatment six replicate plots, each containing 16 trees, were used. Soil samples were taken at the beginning and end of the second season to determine the impact of the treatments on P. megakarya primary inoculum levels as well as the presence of fungal antagonists of P. megakarya. Although soil applications did not significantly reduce the total number of diseased pods, nor overall pod rot rate, soil applications did change disease dynamics by reducing the speed in which the disease progressed. Moreover, soil applications did impact the presence of fungal antagonists and most importantly significantly reduced the amount of P. megakarya primary inoculum present in the soil. Given the effectiveness of T. asperellum in controlling black pod rot, combined aerial and soil applications should have additive effects when combined simultaneously for the control of black pod disease in cacao. Graphical abstract

Source: Biological Control - May 24, 2018 Category: Biology Source Type: research