FBRI State Research Center of Virology and Biotechnology VECTOR, Rospotrebnadzor, 630559, Koltsovo, Novosibirsk Region, Russia.
J Therm Biol. 2021 Dec;102:103123. doi: 10.1016/j.jtherbio.2021.103123. Epub 2021 Nov 10.
Gypsy moth Lymantria dispar (GM) is a polyphagous insect and one of the most significant pests in the forests of Eurasia and North America (U.S. and Canada). Accurate information on GM cold-hardiness is needed to improve methods for the prediction of population outbreaks, as well as for forecasting possible GM range displacements due to climate change. As a result of laboratory and field studies, we found that the lower lethal temperature (at which all eggs die) range from -29.0 °C to -29.9 °C for three studied populations of L. dispar asiatica, and no egg survived cooling to -29.9 °C. These limits agree, to within one degree, with the previously established cold-hardiness limits of the European subspecies L. dispar, which is also found in North America. This coincidence indicates that the lower lethal temperature of L. dispar is conservative. Thus, we found that the Siberian populations of GM inhabit an area where winter temperatures go beyond the limits of egg physiological tolerance, because temperatures often fall below -30 °C. Apparently, it is due to the flexibility of ovipositional behavior that L. dispar asiatica survives in Siberia: the lack of physiological tolerance of eggs is compensated by choosing warm biotopes for oviposition. One of the most important factors contributing to the survival of GM eggs in Siberia is the stability of the snow cover.
舞毒蛾 Lymantria dispar（GM）是一种多食性昆虫，也是欧亚大陆和北美的森林中最重要的害虫之一（美国和加拿大）。准确的 GM 抗寒性信息对于改进预测种群爆发的方法以及预测由于气候变化可能导致的 GM 范围转移是必要的。通过实验室和野外研究，我们发现，三个研究种群的 L. dispar asiatica 的致死低温（所有卵均死亡的温度）范围为-29.0°C 至-29.9°C，而冷却至-29.9°C 时没有卵存活。这些极限与先前建立的欧洲亚种 L. dispar 的抗寒性极限一致，该亚种也在北美发现。这种一致性表明，L. dispar 的致死低温是保守的。因此，我们发现 GM 的西伯利亚种群栖息在冬季温度超出卵生理耐受极限的区域，因为冬季温度经常低于-30°C。显然，正是由于产卵行为的灵活性，L. dispar asiatica 才能在西伯利亚生存：卵的生理耐受缺乏通过选择温暖的生境来产卵来弥补。导致 GM 卵在西伯利亚存活的最重要因素之一是积雪的稳定性。
