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水稻二化螟越冬幼虫在普通低温－15（30d），－20（4，6，8，10d），－23（4d），－25℃（4d）下的死亡率分别为3．33％，6．67％，13．33％，23．33％，26．67％，30％，56．67％；田间越冬初期、中期、后期由低温引起的死亡率分别为0，4．85％，9．96％。越冬幼虫能耐受一定的强低温－28（90min），－30（30min），－32℃（10min）。不同时期越冬幼虫的耐寒性有很大差异，其过冷却点在翌年3月中旬以前呈上升趋势，3月中旬以后又逐渐下降。不同地理纬度区越冬幼虫的耐寒性也有差异，表现为过冷却点随地理纬度的升高而上升。首次提出二化螟在越冬期间通过耐冻和避冻两种策略来越冬。
The mortality rates of overwintering larvae of rice stem borer were 3.33% at normal low temperature -15 (30d), -20 (4,6,8,10d), -23 (4d) and -25 ℃ 6.67%, 13.33%, 23.33%, 26.67%, 30% and 56.67% respectively. The mortality caused by low temperature in early, middle and late winter were 0, 4.85% 9.96%. Overwintering larvae can tolerate a certain low temperature -28 (90min), -30 (30min), -32 ℃ (10min). The cold resistance of overwintering larvae in different periods varied greatly. The subcooling point of the overwintering larvae showed an upward trend before mid-March of the following year, and gradually decreased after mid-March. Cold tolerance of overwintering larvae in different geographic latitudes also showed differences as the subcooling point increased with the increase of geographical latitude. It was first proposed that Chilo suppressalis passed winter by both freezing-thawing and freezing-thawing strategies.