Development of an attract-and-kill strategy for Cocoa Pod Borer (Conopomorpha cramerella Snellen) control

Authors: VANHOVE, WOUTER - Ghent University; Zhang, Aijun; OSMAN, HAFIZ - Barry Callebaut Malaysia Sdn Bhd; VANHOUDT, NIELS - Barry Callebaut Malaysia Sdn Bhd; VAN DAMME, PATRICK - Czech University Of Life Sciences Prague

Submitted to: Pest Management Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/29/2019
Publication Date: 2/23/2019
Citation: Vanhove, W., Zhang, A., Osman, H.I., Vanhoudt, N., Van Damme, P. 2019. Development of an attract-and-kill strategy for Cocoa Pod Borer (Conopomorpha cramerella Snellen) control. Pest Management Science. https://doi.org/10.1080/09670874.2019.1578003.
DOI: https://doi.org/10.1080/09670874.2019.1578003

Interpretive Summary: The yield of cocoa beans in Southeast Asia was significantly affected by infestation of an insect pest of cocoa pod, cocoa pod borer (CPB), and pod losses were up to 50% of the crop. Until now, application of synthetic pesticides was the only conventional intervention for growers to control CPB populations. In previous research, the activity of CPB sex attractant based on our modified synthetic method for more economical production was confirmed in the Malaysia cocoa plantation, which provided the possibility to use it as an alternative to chemical control. In the current follow-up study, the effectiveness of an attract-and-kill strategy based on a sex attractant was tested in a 2-year experiment, with high and low loads of the sex attractant used in attract-and-kill stations. Our results demonstrated that the killing stations with lower dose loads significantly reduced the number of CPB-infested cocoa pods. This useful information will help growers and scientists to develop attract-and-kill strategies based on natural products into efficient, safe, and environmentally friendly CPB-control alternatives, producing high quality chocolate products for worldwide consumers.

Technical Abstract: In South-East Asia, cocoa production is dramatically affected by Cocoa Pod Borer (Conopomorpha cramerella) infestations. As an alternative to hazardous and unsustainable chemical control, the effectiveness of an attract-and-kill strategy using 8 cypermethrin-treated killing stations per ha of cocoa, was tested in two experiments, with 100 µg and 33.3 µg CPB-pheromone loadings in attract-and-kill stations, respectively. In both experiments, insecticide-treated stations significantly (p < 0.05) reduced number of CPB-moths caught in monitoring traps. However, during the first experiment (100 µg pheromone loadings), catch number reduction was not reflected in share of CPB-affected pods. In the second experiment, killing stations (33.3 µg loadings) significantly (p = 0.021) reduced the number of CPB-infested cocoa pods. However, no significant effect on bean yield was found. Results suggest that, contrary to killing stations with 33.3 µg pheromone loadings, those with 100 µg were ineffective in reducing pod loss due to the mating disruption effect of high pheromone doses. More research, testing a broader range of pheromone loadings, different killing station densities and pheromone blends in combination with other insecticides in viscous formulations, is needed to develop the attract-and-kill strategy into an efficient, safe and environmentally friendly CPB-control method.