Effects of Zingiber officinale, Curcuma longa and Alpinia galanga essential oils on the morphological characteristic of cocoa pod borer, Conopomorpha cramerella

Authors: BAKAR, SARIPAH - Malaysian Cocoa Board; LATIP, S.N.H.M. - Universiti Teknologie Petronas; AWANG, ALIAS - Malaysian Cocoa Board; Zhang, Aijun

Submitted to: Journal of Fundamental and Applied Sciences
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/9/2017
Publication Date: 11/10/2017
Citation: Bakar, S., Latip, S., Awang, A., Zhang, A. 2017. Effects of Zingiber officinale, Curcuma longa and Alpinia galanga essential oils on the morphological characteristic of cocoa pod borer, Conopomorpha cramerella. Journal of Fundamental and Applied Sciences. 9(6s):25-38.

Interpretive Summary: Cocoa pod borer (CPB) is one of the most important insect pests and has become a major threat to cocoa growing countries in the South-East Asia region. Crop loss to farmers can be substantial and continuous infestations may cause unacceptable levels of damage, resulting in more than 30% yield loss. Even though integrated pest management strategy and other control approaches were suggested, in most cases, growers still preferred to implement chemical control as a single technique in managing CPB infestation. Biweekly prophylactic treatment with chemical insecticides was considered to be one of the most effective approaches. However, prolonged use of chemical insecticides may produce the risk of insecticide resistance, pose environmental problems, and increase the health risks to the grower. In laboratory bioassay, we discovered that the essential oils obtained from three Zingiberaceae species widely planted in South-East Asia could effectively prevent pupal and larval developments of CPB. In addition, all Zingiberaceae species selected for this study are safe for both human and environmental health. Our research findings enable scientists and growers to develop environmentally friendly pest management alternatives to conventional pesticides for CPB strategic control in cocoa production, therefore, reducing threats to natural ecosystems and human health.

Technical Abstract: The cocoa pod borer, Conopomorpha cramerella, is a major threat to cocoa plantation in the South-East Asia region. The infestation in Malaysia is very serious; even several control approaches are suggested to the growers. However, heavy reliance and prolonged use of synthetic chemical insecticide in managing this pest may lead to resistance mechanism, therefore environmentally friendly approach using natural product is an attractive alternative for use in pest management due to its reduced threat to human and environmental health. Three Zingiberaceae species, Zingiber officinale, Curcuma longa, and Alpinia galangal widely planted in Malaysia, were selected for this study. The pupicidal activities of commercially available essential oils from above Zingiberaceae species were evaluated in laboratory bioassays against C. cramerella. All Zingiberaceae essential oils showed promising results, in which percentages of deformed pupa were more than 40% and percentages of healthy adult emergence were less than 50%. Overall results showed that Z. officinale, C. longa, and A. galanga essential oils have great potentials to be used as part of biological control strategies in cocoa plantation for C. cramerella management in the future.