Optimal Low Temperature and Chilling Period for Both Summer and Winter Diapause Development in Pieris melete: Based on a Similar Mechanism

Abstract

The cabbage butterfly, Pieris melete hibernates and aestivates as a diapausing pupa. We present evidence that the optimum of low temperature and optimal chilling periods for both summer and winter diapause development are based on a similar mechanism. Summer or winter diapausing pupae were exposed to different low temperatures of 1, 5, 10 or 15°C for different chilling periods (ranging from 30 to 120 d) or chilling treatments started at different stages of diapause, and were then transferred to 20°C, LD12.5∶11.5 to terminate diapause. Chilling temperature and duration had a significant effect on the development of aestivating and hibernating pupae. The durations of diapause for both aestivating and hibernating pupae were significantly shorter when they were exposed to low temperatures of 1, 5 or 10°C for 50 or 60 days, suggesting that the optimum chilling temperatures for diapause development were between 1 and 10°C and the required optimal chilling period was about 50–60 days. Eighty days of chilling was efficient for the completion of both summer and winter diapause. When chilling periods were ≥90 days, the durations of summer and winter diapause were significantly lengthened; however, the adult emergence was more synchronous. The adaptive significance of a similar mechanism on summer and winter diapause development is discussed.

Energy and lipid metabolism during direct and diapause development in a pierid butterfly

“…Wiklund and Solbreck, 1982). An increase in development rate with time spent in diapause has also been suggested in other butterflies (Wiklund and Solbreck, 1982;Gray, 2009;Xiao et al, 2013;Stålhandske et al, 2015). Also, the rising MR slope reflects an accelerated postdiapause developmental rate with time spent at 2°C.…”

Effect of winter cold duration on spring phenology of the orange tip butterfly, Anthocharis cardamines

“…The effect of chilling is both an increased developmental sensitivity to increasing spring temperatures and an increased synchrony in hatching for a given spring temperature (e.g., Xiao et al. 2013; Chen et al. 2014; Stålhandske et al.…”

“…2014) and insects (Collier and Finch 1983; Bosch and Kemp 2003; Chuche and Thiéry 2009; Xiao et al. 2013; Williams et al. 2015b).…”

“…There are also some studies on insects showing that developmental trajectories are indeed affected by cold duration, which may serve to synchronize local populations (Xiao et al. 2013; Chen et al. 2014).…”

Prolonged coldness on eggs reduces immature survival and reproductive fitness in Tetranychus urticae (Acari: Tetranychidae)

“…Third, compared to that tested in this study, eggs laid by the overwintering adults will survive better and can survive at least for four days or longer when temperature is ≈ 5 °C in spring, as eggs matured in mother's ovaries have experienced and thus adopted to the adverse environmental conditions. Prolonged chilling required for terminating winter diapause is often reported (i.e., Tauber & Tauber 1976;Tauber et al 1986;Xiao et al 2013). To our best knowledge, chilling is more frequently reported to arrest rather than accelerate the development of immature stages, and most studies are relevant to mass production, storage, shipment and release of natural enemies in biological control programs (van Lenteren & Tommasini 2003;Lins 2013;Ismail et al 2014).…”