Effects of photoperiod and temperature on reproductive diapause in Ophraella communa (Coleoptera: Chrysomelidae), a potential biocontrol agent against Ambrosia artemisiifolia

Abstract

To investigate the seasonal adaptation strategies of Ophraella communa to new habitats, the effects and regulation mechanisms of photoperiod and temperature on the reproductive diapause in a population collected from Changsha, Hunan were examined. Adults showed obvious reproductive diapause, which was regulated by photoperiod and temperature. At 30°C, there was no adult diapause occurring under either long‐day or short‐day conditions; at 25°C the pre‐oviposition period was short and fecundity was high in adult females under L : D 16 : 8 h, whereas under L : D 12 : 12 h, a few females entered reproductive diapause; at 20°C under short‐day conditions, all female adults entered diapause. The pre‐oviposition period was significantly prolonged when the pupae and adults were transferred from long‐days to short‐days, but the day length influence was not obvious when they were transferred only in the adult stage. However, the fecundity dropped greatly no matter whether the photoperiod shifted to short‐days only in the adult stage or whether the shift occurred in both the pupal and adult stage. The fecundity was extremely low when photoperiod shifted from long‐days to short‐days in both pupal and adult stages. This was an indication that the pupal and adult stages were the photoperiod‐sensitive stage for adult reproductive diapause. This was especially true for the photoperiod in the pupal stage, which has a distinctly significant regulative effect on reproductive diapause. Additionally, this article also addresses the reason for different photoperiodic response patterns in reproductive diapause induction between the Changsha strain and the Tsukuba strain (Japan) of O. communa.

Life History Characteristics ofDiorhabda CarinulataUnder Various Temperatures

“…Therefore, our results of the effects of temperature on developmental time in the tamarisk leaf beetle suggest that there may be an optimal temperature range beyond which developmental time is signiÞcantly impacted. This was also shown in results by Zhou et al (2010) on the leaf beetle Ophraella communa (LeSage). In their study on the effects of temperature on developmental time, the optimal range for development for O. communa was between 25 and 28ЊC.…”

Is the recent decrease in airborne Ambrosia pollen in the Milan area due to the accidental introduction of the ragweed leaf beetle Ophraella communa?

“…Females lay eggs every few days for a month or more, with the fecundity exceeding 2700 eggs/female (Futuyma et al 1993;Zhou et al 2010b). The survival rate of eggs and larvae is higher, and the development periods shorter, when temperature and humidity are increased (Zhou et al 2010a, b;Zhu et al 2012). Both the larva and imago feed on leaves of A. artemisiifolia (Wan et al 2009).…”

Rapid evolution of an introduced insect Ophraella communa LeSage in new environments: temporal changes and geographical differences in photoperiodic response

“…Low temperature also affected induction of its diapause (Zhu et al . ). In the present study, the larvae and adults of O .…”

“…This study examined only the effect of photoperiod on diapause of O. communa but did not address other environmental conditions that may influence diapause of this species. Low temperature also affected induction of its diapause (Zhu et al 2012). In the present study, the larvae and adults of O. communa were supplied with ragweed leaves at the growing stage before flowering.…”