《环境昆虫学报》

作者	单位
任小云, 张礼生*, 齐晓阳, 安涛, 韩艳华, 陈红印	（中国农业科学院植物保护研究所，植物病虫害生物学国家重点实验室，北京 100081）

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中文摘要:

滞育是部分昆虫固有的适应逆境胁迫的遗传属性，七星瓢虫具有显著的滞育现象。本文以七星瓢虫雌成虫为试材，研究正常发育、滞育及滞育解除后3组处理试虫糖、脂、蛋白等关键代谢物质含量波动规律，总结滞育期间的代谢适应特点，解析其与过冷却能力的相关性，探索滞育对七星瓢虫逆境胁迫耐受力的促升效应，丰富七星瓢虫的滞育基础理论研究。利用物质干湿重差数法测定七星瓢虫的含水量；利用氯仿-甲醇（体积比为2∶1）法抽提除去自由水个体的脂肪；总糖、海藻糖、甘油、山梨醇及总蛋白的测定采用标准曲线法，利用SUN-II型智能昆虫过冷却点测定仪测定七星瓢虫的过冷却点（supercooling point，SCP）。结果表明，七星瓢虫滞育组含水量（58.11%±6.55%）显著低于正常发育组（68.49%±2.26%）和滞育解除组（65.84%±4.02%）（F=8.15，P<0.01），滞育解除后含水量恢复至正常发育组水平；滞育组总糖（10.60±0.54 μg/mg）、糖原（8.72±0.62 μg/mg）、脂肪（173.66±19.01 μg/mg）含量远远高于正常发育组和滞育解除组（F=46.57，P=0.0006；F=114.25，P<0.0001；F=8.48，P<0.01）；滞育组总蛋白含量（49.20±3.80 μg/mg）显著低于正常发育组（71.02±6.15 μg/mg）和滞育解除组（69.45±4.66 μg/mg）（F=46.57，P=0.0006）；滞育组中海藻糖（1.31±0.27 μg/mg）、甘油（1.74±0.50 μg/mg）、山梨醇（9.84±3.02 μg/mg）含量与正常发育组、滞育解除组无显著性差异（F=0.79，P=0.4946；F=1.33，P=0.3004；F=1.69，P=0.2387）。七星瓢虫在滞育条件下其过冷却点（-16.53℃±1.44℃）显著低于正常发育组（-14.07℃±1.33℃）和滞育解除组（-15.29℃±2.10℃）（F=13.47，P<0.0001），经过滞育低温驯化后滞育解除组过冷却点较对照组有所降低。滞育诱发七星瓢虫发生显著的代谢适应，蛋白含量显著降低，抑制新陈代谢进程；糖脂含量显著升高，保障滞育维持及解除后发育的能量需求；七星瓢虫滞育属糖原积累型；滞育个体过冷却点大幅下降，耐寒性显著提升。

英文摘要:

Diapause is an inherent genetic attribute of some insect species to adapt adverse stress, and there exists an obvious diapause phenomenon in the ladybird, Coccinella septempunctata. In this paper, biochemical substances and supercooling point of C. septempunctata female adults under three different treatments (normal development, diapause, post-diapause) were detected aiming at understanding the fluctuations of critical metabolites such as sugar, lipid, and protein of diapausing ladybird, summarizing the characteristics of metabolism adaption during diapause and the correlation with supercooling point, and exploring the booster effect of stress tolerance under diapause, which will enrich the diapause basic theory research of Coccinella septempunctata. Water content was detected by the differences between wet and dry weight; lipid was extracted by the mixture of chloroform and methanol (v∶v=2∶1); total sugars, trehalose, glycogen, glycerol, sorbitol, and proteins were detected by standard curve methods; the SCP was tested by SUN-II type insect supercooling point detector. It indicated that diapausing adults had the lowest water content (58.11%±6.55%) within the three treatments (F=8.15, P<0.01). The contents of sugars (10.60±0.54 μg/mg), glycogen (8.72±0.62 μg/mg) and lipid (173.66±19.01 μg/mg) of diapausing group were much higher than both control group and post-diapausing group (F=46.57, P=0.0006; F=114.25, P<0.0001; F=8.48, P<0.01); the contents of total proteins in the three groups were in the reverse-The content of diapausing group (49.20±3.80 μg/mg) was lowest (F=46.57, P.=0.0006); trehalose (1.31±0.27 μg/mg), glycerol (1.74±0.50 μg/mg) and sorbitol (9.84±3.02 μg/mg) of diapausing group had no significance with the others'. Diapausing C. septempunctata (-16.53℃±1.44℃) had the lowest SCP, which was significantly lower than normal developmental group (-14.07℃±1.33℃) and post-diapause group (-15.29℃±2.10℃) (F=13.47, P<0.0001); the post-diapause group via cold acclimation of diapause had lower SCP than normal developmental group. In conclusion, diapause can significantly induce metabolic adaption of C. septempunctata; protein content is significantly lower which means metabolic process is suppressed in diapausing adults; the contents of sugars and lipid improve dramatically guaranteeing the need of energy reserves for diapause maintenance and post-diapause development; C. septempunctata diapause can be divided into glycogen accumulation. Cold resistance of diapause individuals has a significant promotion with the lowest SCP.

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