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 a major source of grain reserve depletion. Fungi and insect pests both damage grains synergistically in the store. Fungal and insect pest infestations pose nutritional damage to the stored food which becomes unpalatable for the consumer. There is a need to develop a timeline for synergistic damage caused by insect pest and mycotoxigenic fungi to manage them in stored products. For this purpose, interaction of mycotoxigenic fungi (Aspergillus flavus, Aspergillus niger, Penicillium digitatum and Alternaria alternata) along with C. maculatus (Fabricius) (Bruchidae: Coleoptera) was studied at wide range of temperature. Development of C. maculatus was observed on fungus inoculated and non-inoculated C. arietinum seeds under different temperatures. C. maculatus was found attracted for completion of its life cycle attributes (Fecundity, larval emergence, pupae and adults) in fungus inoculated grains. Population of C. maculatus was decreased by increase in temperature but high temperatures pose to more fungi developments. Meanwhile, more egg laying was observed at 27 ºC and 33 ºC. At tested temperatures, larval emergence was high as compared other checked life attributes. Infestation of A. flavus and A. niger was also increased with different life stages of C. maculatus at all checked temperatures. Penicillium digitatum and Alternaria alternata infestation were increased in the C. arietinum at 27 ºC and 30 ºC respectively. This study will help in measuring the control practices of fungi and insect pest infestations in stored chick pea in Pakistan.