冷驯化对油松毛虫越冬幼虫过冷却点及 主要耐寒物质的影响
Effects of cold acclimation on the supercooling point and major cold hardiness chemicals of overwintering Dendrolimus tabulaeformis larvae
邵钰莹1** 冯宇倩2 田 斌1 宗世祥1***
点击：1164次 下载：5次
DOI：10.7679/j.issn.2095-1353.2017.115
作者单位：1. 北京林业大学林木有害生物防治北京市重点实验室，北京 100083； 2. 中国林业科学研究院林业新技术研究所森林病原整合生物学研究室，北京 100091
中文关键词： 油松毛虫，幼虫，不同越冬阶段，冷驯化，过冷却点，耐寒物质
英文关键词：Dendrolimus tabulaeformis, overwintering periods, larvae, cold acclimation, supercooling point, cold hardiness substances
中文摘要：
【目的】 冷驯化可增强昆虫的耐寒性，本文研究旨在明确不同冷驯化条件下油松毛虫Dendrolimus tabulaeformis Tsai et Liu越冬幼虫的过冷却点和主要耐寒物质的变化规律。【方法】 利用热电偶方法测定越冬幼虫的过冷却点，分别采用差量法、氯仿甲醇法、苯酚硫酸法及毛细管气相测谱法测定其含水率、脂肪、糖原和小分子糖醇的含量。【结果】 冷驯化会导致幼虫含水率显著降低；过冷却点和脂肪含量在低于环境气温5℃冷驯化后显著降低，当驯化温度低于环境气温10℃及以上则升高；糖原含量在9月份显著增加，越冬中期（1、3月份）含量略有降低但不显著；小分子糖醇含量的变化均不显著；海藻糖含量略降低；甘油、葡萄糖和半乳糖含量在低于环境气温5℃冷驯化后略降低，低于环境气温10℃冷驯化则升高。【结论】 冷驯化使幼虫虫体含水率和脂肪含量降低，糖原含量提高，从而导致其过冷却点降低，耐寒能力提高；冷驯化的温度和时间均会影响其过冷却能力，在最适合的温度和时长可以最大程度提高其耐寒能力。研究结果为揭示油松毛幼虫的耐寒机制及潜在分布区预测提供了科学依据。
英文摘要：
[Objectives] To explore the effects of cold acclimation on the cold hardiness of overwintering Dendrolimus tabulaeformis larvae. [Methods] Changes in supercooling point and major cold hardiness chemicals were measured. A thermocouple was used to measure supercooling points. Moisture, lipid, glycogen and small molecule sugar and alcohol content of larvae were determined using the delta rule, the chloroform-methanol method, phenol-sulfuric acid method and capillary gas chromatography, respectively. [Results] The moisture content, supercooling point and lipid content of D. tabulaeformis larvae acclimated to within 5℃ below ambient temperature declined significantly, but increased in larvae acclimated to within 10℃ below ambient temperature. Glycogen content significantly increased in September, but decreased slightly in January and March after cold acclimation. Changes in small molecular sugar and alcohol content were not significant. Trehalose content slightly decreased and glycerol, glucose and galactose decreased in larvae acclimated to within 5℃ below ambient temperature, but increased when larvae were acclimated to temperatures 10℃ below ambient temperature. [Conclusion] The observed changes in moisture, lipid, glycogen content and small molecular sugar and alcohols suggest that cold acclimation can increase the cold hardiness of D. tabulaeformis. The supercooling ability of D. tabulaeformis appears to be affected by both temperature and the time of cold acclimation, which suggests that there are optimal acclimation conditions that can maximize cold hardiness. These results provide a theoretical basis for revealing the cold hardiness mechanism and potential distribution of D. tabulaeformis.