Pupal diapause of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) mediated by larval host plants: pupal weight is important

▶ Cues associated with diapause have focused primarily on temperature and photoperiod; host plants have received limited attention. ▶ Here, we reported a facultative diapause in Helicoverpa armigera mediated by host plant and found diapause incidence to be affected by larval host plants. ▶ Further analysis showed that pupal weight rather than development duration affected doapause occurrence. ▶ Starvation experiments causing body size differences further confirmed diapause incidence is a function of pupal weight. ▶ H. armigera appears to have evolved a mechanism of diapause incidence based on pupal weight to maximize its fitness.