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期 刊 ：植物保护学报 2010年

关键词：亚洲玉米螟；滞育；过冷却点；抗寒性；低温生存对策；

Keywords:Ostrinia furnacalis, diapause, supercooling point, cold hardiness, strategies,

摘 要 ：为了明确亚洲玉米螟Ostrinia furnacalis (Guene)的抗寒及低温生存对策,分别测定了来自吉林省的敦化一化型(DH₁)、公主岭一化型(GZL₁)、公主岭二化型(GZL₂)和洮南二化型(TN₂)4个亚洲玉米螟滞育幼虫田间种群的过冷却点和结冰点,以及各种群经超过冷却低温处理后的存活率及滞育后发育历期等。结果显示,亚洲玉米螟滞育幼虫的过冷却点为-28.5~-27.0℃,最低个体可达-36.4℃,不同种群间存在显著差异,以GZL₁最低,其次是TN₂和DH₁,GZL₂最高。在超过冷却点低温下,各种群的存活率分别为45.6%、58.8%、41.8%和58.3%,且GZL₁和TN₂显著高于DH₁和GZL₂,在超过冷却低温处理下存活的幼虫其滞育后发育历期与未经过处理的同种群对照间没有显著差异。这表明亚洲玉米螟具有很强的过冷却能力,同时还具有很强的耐结冰能力。

Abstract:Ostrinia furnacalis (Guene) overwinters as diapausing larva in northern China. The survival of overwintering larvae affects the first generation population density of next year. Cold hardiness of diapausing overwintering larvae plays an important role in their overwintering survival. The cold hardiness of diapausing larvae of 4 field populations from Jilin Province, i.e. Dunhua univoltine (DH₁), Gongzhuling univoltine (GZL₁), Gongzhuling bivoltine (GZL₂), and Taonan bivoltine (TN₂), were measured by exposing testing their supercooling point (SCP) and freezing point (FP). Cold tolerance was measured by testing the survival of diapausing larvae at supercooled temperature. The results showed that the SCPs of O.furnacalis varied from -28.5℃ to -27.0℃, the lowest SCPs of individual could be as low as -36.4℃. There were significant differences in SCPs among the four populations. GZL₁ performed the lowest SCP, whereas GZL₂ performed the highest. The survival of diapausing larvae at supercooled low sub-zero temperature -40℃ were 45.6%, 58.8%, 41.8%, and 58.3% for GZL₁, TN₂, DH₁, and GZL₂ populations, respectively. There was not significant difference in larvae survival of supercooled populations and that of non-supercooled original population at post-diapausing developmental stage. These results suggested that O.furnacalis diapausing larva populations could take advantage of supercooling, and part of them also perform freeze tolerance, indicating that O.furnacalis performed two strategies for survival at low temperature in diapause overwintering larvae, which were freeze avoidance and freeze tolerance.

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