Variations in life-history traits of phytophagous fly, Atherigona pulla (Muscidae: Diptera) in different phenological stages of host-plants

The phytophagous fly species of Atherigona are commonly known as ‘shoot flies’ due to larval feeding inside growing shoots of many cultivated and wild grasses in tropical world. Several species of shoot flies occur on cereals and millets with remarkable specificity for host-plant species. Atherigona pulla (Wiedemann) is a serious pest on two small millet crop species Panicum miliaceum and P.sumatrense in India. Several overlapping generations of A.pulla occur during the crop growth period starting from as early as three-leaf seedling stage to panicle initiation stage of P. miliaceum and P.sumatrense. We analysed the life history traits (such as pupal size, adult longevity, sex ratio, egg size, and parasitisation by braconid and eulophid wasps) of A.pulla at four different plant phenological stages. The results showed significant differences in all the life-history traits between host-plant phenological stages. The results signify the fitness of the fly species to survive through various phenological stages of its host-plants.