Vol. 14(16), pp. 1364-1372, 22 April, 2015 DOI: 10.5897/AJB2014.14277 Article Number: 5BA702852400 ISSN 1684-5315 Copyright © 2015 Author(s) retain the copyright of this article http://www.academicjournals.org/AJB African Journal of Biotechnology Full Length Research Paper Developmental response of tropical warehouse moth, Ephestia cautella (Walker) (Lepidoptera: Pyralidae)'s larvae to stored cocoa beans fermented at varied degrees Oyedokun, Adegoke Victor* and Omoloye, Amos Adebayo Department of Crop Protection and Environmental Biology, University of Ibadan, Nigeria. Received 27 October, 2014; Accepted 30 March, 2015 Developing larvae of major insect pests like Ephestia cautella rapidly degrade stored cocoa beans through feeding and other biological activities on the beans. Completion of developmental stages of insects may be influenced by a number of biochemical factors triggered by the primary post-harvest processing of cocoa beans prior to storage. Hence, this study assessed the development of E. cautella from first instar larval stage to adult stage on cocoa beans fermented at varied degrees. Fresh ripening pods of Amelonado variety (N38) were harvested and fermented variedly at 0 - 7 days, and sun-dried to about 5-6% moisture content. The variedly fermented cocoa beans (300 g/treatment) were infested with newly hatched first instar larvae of E. cautella (N=10) in a completely randomized design with four replications at 28±2°C and 70±5% relative humidity (RH). Days to adult emergence of the larvae of E. cautella on the cocoa beans varied significantly (P>0.05) between 0 day and 76.50 days in 4 days and 7 days-fermented beans, respectively. Significant variations occurred (P>0.05) in the total adult emergents of E. cautella, ranging between 0 and 8.25 in 4 days and 1 day fermented beans, respectively. This study reveals that the fermentation period of cocoa beans prior to drying and storage influenced adult emergence of E. cautella on stored cocoa beans, with 0 - 3 days fermented beans highly susceptible to E. cautella’s development to adult stage. Cocoa beans need to be fermented adequately for 4 to 7 days before drying to prevent insects’ damage. Notably, 4-days fermented cocoa beans did not support E. cautella development to adult stage at 90 days post larvae-introduction. The 4-days fermented cocoa beans require further investigations for its nutritional suitability and importance in human diets. Key words: Varied fermentation, Ephestia cautella, total adult emergents, days to adult emergence. INTRODUCTION Cocoa is a major export and source of income in some countries in West Africa including Nigeria (Tah et al., 2011) and is widely cultivated in the tropical rain forest and adjoining rain-fed ecologies in Nigeria (Opeke, 2005). Nigeria is the fourth largest producer of dried cocoa beans in the world after Cote d’Ivoire, Ghana and Indonesia with an average output of about 225,000 - 245,000 metric tons between 2011 and 2013