Temperature mediated influence of mycotoxigenic fungi on the life cycle attributes of Callosobruchus maculatus F. in stored chickpea

Abstract

Environmental factors (biotic and abiotic) are major depletion reasons in granaries. Fungi and insect pests act synergistically in deterioration of grains in storages which results in nutritional damage to the stored food which becomes unpalatable for the consumer. There is a need to establish a timeline for synergistic damage caused by insect pests and mycotoxigenic fungi for better management. For this purpose, interaction of mycotoxigenic fungi (Aspergillus flavus, Aspergillus niger, Penicillium digitatum and Alternaria alternata) with Callosobruchus maculatus (F.) (Coleoptera: Chrysomelidae) was studied at different temperatures. Development of C. maculatus was observed on fungus inoculated and uninoculated C. arietinum seeds. In fungus inoculated grains the development (Fecundity, larval emergence, pupation rate and adult emergence) of C. maculatus was found more better as compared on uninoculated grain. The population of C. maculatus was decreased by increase in temperature but high temperatures favours more fungi developments. More egg laying was observed at 27 °C and 33 °C. At tested temperatures, larval emergence was high as compared to other observed life attributes. Infestation of A. flavus and A. niger was also increased with increase of temperatures. Penicillium digitatum and A. alternata infestation were increased in the C. arietinum at 27 °C and 30 °C respectively. This study will help in measuring the control practices of fungi and insect pest infestations in stored C. arietinum (chickpea) in Pakistan.

Keywords

• Insect microbial interaction
• C. maculatus
• Growth parameters
• Ecophysiological factors