|VANHOVE, WOUTER - Ghent University|
|VANHOUDT, NIELS - Collaborator|
|BHANU, KARUMURU RAJA M - Pest Control, Ltd|
|DAMME, PATRICK VAN - Ghent University|
|YU, MENGMENG - China Agricultural University|
Submitted to: Journal of Applied Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/7/2015
Publication Date: 2/27/2015
Citation: Vanhove, W., Vanhoudt, N., Bhanu, K., Damme, P., Abubeker, S.U., Zhang, A. 2015. Geometric isomers of sex pheromone components do not affect attractancy of Conopomorpha cramerella in cocoa plantations. Journal of Applied Entomology. DOI:10.1111/jen.12212.
Interpretive Summary: The cocoa pod borer (CPB) is one of the most important insects affecting cocoa production in Southeast Asia. This pest is responsible for up to 50 % of cocoa crop losses in Malaysia. Until now, management of CPB has heavily relied on pesticide applications, which is neither environmentally sustainable nor economically effective. Our previous research confirmed the activity of the CPB sex attractants in the Indo-Malayan archipelago region. However, application of the sex attractant against CPB was halted due to economic reasons and lack of commercial quantities. In this study, we modified the synthetic method for improved economical production of the CPB sex attractant. Field tests conducted in Malaysia during 2013 – 2014 indicated that other non-target compounds and impurities generated during this modification did not reduce the attractancy of CPB in the cocoa plantation. This result will provide much needed insights into CPB management for growers and scientists to help develop more cost effective control strategies based on natural products, resulting in better quality cocoa beans as well as better chocolate products for world wide consumers.
Technical Abstract: Sex pheromone of cocoa pod borer (CPB), Conopomorpha cramerella, has previously been identified as a blend of (E,Z,Z)- and (E,E,Z)-4,6,10-hexadecatrienyl acetates and the corresponding alcohols. These pheromone components have been synthesized with modification of the existing method and relative attractancy of synthetic blends with different levels of non-target pheromone components and chemical purities was tested in a cocoa field using Delta traps. It was found that male captures were not significantly different from traps baited with pheromone blends containing 5% to 47% (based on four identified pheromone components) other geometric acetates [(E,Z,E)-, (Z,Z,Z)-, (Z,E,Z)-, and (Z,E,E)-4,6,10-hexadecatrienyl acetates]. This result indicates that C. cramerella males did not discriminate among the pheromone components and other geometric isomers in the blends. Therefore, neither antagonistic nor synergistic effect from other pheromone geometric isomers was observed. The modified synthetic pathway is offering the prospect of more economical production of CPB sex pheromone. During the 17 weeks in which C. cramerella monitoring concurred with the main harvest period of 2013 - 2014, CPB trap catch data from above blends showed a good correlation with the number of pods with C. cramerella infestation symptoms.