Pesticidal activities of selected zingiberaceae species against cocoa pod borer, other pests and beneficial insects / Saripah Bakar

Conopomorpha cramerella, (Lepidoptera: Gracillariidae) has been identified as the major pest causing significant damage to cocoa production in Southeast Asia. The management is focused on the use of synthetic insecticides, whereas the utilization of biopesticides receives comparatively little attention. Botanical extracts have potential as biopesticide due to their target-specific nature, biodegradability and utilization in pest management programs. The primary objective was to investigate the biopesticide potential of Zingiberaceae species, Alpinia galanga (lesser galanga), Curcuma longa (turmeric), and Zingiber officinale (ginger). Bioassays were conducted to investigate the effects of plant extracts and essential oils on the egg, pupa, and adult of CPB. The experimental observation revealed that Z. officinale and A. galanga have the capability to influence the oviposition behavior, facilitate effective egg penetration, increased malformations in pupa and adult, and decrease egg hatchability. The development of two concentrations of potential botanical pesticides was conducted using an emulsion formulation utilized from stripped palm oil methyl esters (SPME), combined with Z. officinale and A. galanga EOs. The composition of the emulsion consisted of 5% SPME, 2.16% Tween® 80, 0.64% Span® 80, and 90% water, resulting in a hydrophilic-lipophilic balance (HLB) value of 12. The formulation exhibited compliance with the quality parameters specified by the Food and Agriculture Organisation (FAO). The formulations underwent testing in laboratory and field against CPB, Helopeltis, and leaf-eating insects. The results demonstrated promising outcomes, with A. galanga F2 and Z. officinale F2 performing similar results or, in certain tests outperforming insecticides, particularly when at higher concentrations. The formulations likewise have minimal influence on the beneficial insects of cocoa. Based on the findings, the potential of utilizing Zingiberaceae-based botanical pesticide as an ecologically sustainable method for cocoa pest management appears promising for cocoa producers in the near future.