【作者】 陈红松；

【导师】 万方浩； 高必达；

【作者基本信息】 湖南农业大学 ， 生物安全与检疫， 2012， 博士

【摘要】 广聚萤叶甲(Ophraella communa)是入侵杂草豚草的专一性天敌,前期研究结果表明,36℃高温饲养一个世代对其发育与繁殖造成不利影响。结合湖南长沙夏季极端温度变化情况,本文设40、42、44℃,不同虫态在每天12：00-15：00时段连续处理3-5d和持续处理一个世代,随后考察广聚萤叶甲发育、繁殖、生理代谢物质及保护酶活性的变化。具体结果如下：1异常高温对广聚萤叶甲发育与繁殖的影响异常高温胁迫各虫态后,其存活率随温度升高而降低。卵和幼虫可耐受40℃高温胁迫,在各温度下蛹和成虫存活率均较高,耐高温能力为：成虫>蛹>幼虫>卵。持续高温胁迫整个世代后,对广聚萤叶甲的生存影响显著。高温胁迫下雌性比率明显增高。除40℃,异常高温胁迫显著降低雌虫繁殖力,且高温胁迫具有明显累积效应。异常高温胁迫各虫态后,成虫寿命总体上有所延长；42℃及以下高温持续胁迫一个世代后,成虫寿命延长,而44℃高温持续胁迫后,成虫寿命缩短。2异常高温对广聚萤叶甲体形特征参数的影响段性(不同虫态)和持续性(整个世代)异常高温胁迫均可显著抑制成虫体长的增长,且持续高温胁迫对成虫体长的影响更为显著。异常高温胁迫不同虫态后,成虫的体重降低不明显：异常高温持续胁迫整个世代后,成虫的体重显著降低。表明高温胁迫对成虫体长和体重的影响具有显著的累积效应。3广聚萤叶甲对异常高温响应的生理代谢机制异常高温胁迫对广聚萤叶甲体内含水率、总糖、糖原、脂肪、甘油和羟脯氨酸含量造成显著影响。异常高温胁迫各虫态后,各虫态以40℃胁迫处理的成虫含水率最高；各温度胁迫处理则以卵受胁迫后,成虫含水率最高。异常高温胁迫各虫态后,雌虫总糖含量总体上都有所增高,且高于雄虫。卵和幼虫经高温胁迫后,雄虫总糖含量增高,但蛹和成虫受胁迫后,雄虫总糖含量降低。在高温持续胁迫(整个世代)下,雌、雄成虫总糖含量随温度升高而降低。高温胁迫不同虫态后,成虫糖原含量高于对照；在高温持续胁迫下成虫糖原含量显著高于对照。除40℃胁迫卵及幼虫外,高温胁迫各虫态后,成虫体内脂肪含量均显著低于对照。除40℃胁迫的雄虫外,在高温持续胁迫下,成虫体内脂肪含量随温度升高而降低,雌虫显著高于雄虫。异常高温胁迫不同虫态后,雌虫体内的羟脯氨酸含量降低,而雄虫羟脯氨酸含量则呈增高趋势；在40℃及以上高温持续胁迫下,雄虫羟脯氨酸含量增高,且显著高于雌虫。异常高温胁迫不同虫态和整个世代后,成虫甘油含量均显著增高。这些成虫体内生理代谢物质的变化是广聚萤叶甲应对高温胁迫的一种积极响应。4异常高温胁迫下广聚萤叶甲体内保护酶活性变化异常高温胁迫不同虫态后,成虫蛋白质含量总体上有所降低；而在高温持续胁迫下,雌虫蛋白质含量降低,雄虫蛋白质含量有所增高。异常高温胁迫各虫态后,成虫体内SOD活性增高；但高温持续胁迫下,成虫体内SOD活性明显降低。异常高温胁迫各虫态后,成虫CAT活性有所增高,以胁迫幼虫后,成虫CAT的活性最高。异常高温持续胁迫下,雌虫CAT活性随温度升高先升后降,42℃下最高,雄虫CAT活性较平稳,44℃胁迫处理的雄虫CAT活性显著低于对照。异常高温胁迫各虫态后,成虫POD活性降低；异常高温持续胁迫下,雌虫POD活性随温度升高而降低,雄虫POD活性受影响较小。三种酶活性顺序为SOD>POD>CAT,抵抗氧化胁迫的贡献率为SOD>CAT>POD,说明高温引起了氧化胁迫,而广聚萤叶甲可抵抗42℃及以下高温造成氧化胁迫的影响。更多还原

【Abstract】 Ophraella communa, a ragweed leaf beetle, is the host-specific natural enemy of the invasive ragweed, Ambrosia artemisiifolia. Previous study showed that laboratory rearing temperature of36℃affected adversely its development and reproduction. Based on abnormal high temperature changes in summer months in Hunan provinces, the3hours-heat-shock treatements of different stages of O. communa at temperature of40,42,44℃for continuous3-5days and were conducted, and the continuous high temperature treatments of a complete generation of of O. communa were also run at the above temperatures in order to test the heat-tolerance of the beetle,the reproduction, physiological metabolites and protective enzymes activity. The results as follows:1The effect of abnormal high temperature stresses on the development and reproduction of O. communaThe survival rates of O. communa decreased with the increasing temperature when the different stages of O. communa were stressed by abnormal high temperatures. Egg and larva can suffer the high temperature stress of40℃, and the survival rates of pupae and adult were higher at all temperatures. Capability of tolerance to high temperature was adults> pupae> larvae> eggs. The survival of O. communa was significantly affected by continuous high temperature stress of a generation. Female ratio was significantly higher under high temperature stress. Except for40℃, abnormal high temperature stress was significantly lower female fecundity, and high temperature stress had a significant cumulative effect. The adult longevity was significantly extended when the different stages were stressed by abnormal high temperatures. The adult longevity would be extended when the generations were stressed by abnormal constant high temperatures, but when the temperature reached44℃, the adult longevity would be shorten.2The effect of abnormal high temperature stresses on the body characteristic parameters of O. communaThe growth of the adult O. communa body length could be significantly inhibited by segmental (different stages) and continuous (a generation) abnormal high temperature stresses, and the effect of continuous (a generation) abnormal high temperature stress was more significant. The lost adult weight was not obvious when the different stages were stressed by abnormal high temperatures. When the generation were stressed by abnormal high temperatures the lost adult weight was significant. It showed that the cumulative effect of high temperature stress had a significant impact on adult body length and weight.3Physiological metabolic mechanisms of O. communa to abnormal high temperature stressesThe water, total sugar, glycogen, fat, glycerin and hydroxyl proline content of O. communa were significantly affected by abnormal high temperature stress. When the different stages of O. communa were stressed by abnormal high temperatures, the adult water content of all treated stages of O. communa was the highest at40℃, while when the eggs after being stressed, the adult water content was the highest. Generally, the female total sugar content had increased after different stages stressed by abnormal high temperatures, and which was higher than male. Male total sugar content would increase after egg and larva were stressed by high temperature, which would decrease when pupa and adult were stressed by high temperature. Both female and male total sugar content decreased as the temperature increasing, when the high temperatures continued to stress (a generation). The adult glycogen content was higher than the control, when the different stages were stressed by high temperature, and male glycogen content was higher than female. In addition to the stress of egg and larva at40℃, adult body fat content were significantly lower than the control after different stages stressed by different high temperatures. In addition to the stress of male at40℃, the adult body fat content decreased as temperature increasing after high temperature continues being stressed, and female body fat content was significantly higher than male. After the different stages of O. communa were stressed by abnormal high temperatures, the female hydroxyproline content decreased, while the male body hydroxyproline content showed an increasing trend. When the continued stressed high temperature was no less than40℃, male hydroxyproline content increased, which was significantly higher than female. The adult glycerol content was significantly increased, when different stages and a generation were stressed by abnormal high temperatures. These changes of adult physiological metabolites were a positive response of O. communa to high temperature stress.4The protective enzyme activities of O. communa changes under abnormal high temperature stressesThe adult protein content was significantly reduced after different stages of O. communa were stressed by abnormal high temperatures. After high temperature continues being stressed, the female protein content decreased, while the male protein content increased. After different stages of O. communa were stressed by abnormal high temperatures, adult body SOD activity increased, but the adult SOD activity was significantly decreased after high temperature continues being stressed. After different stages were stressed by abnormal high temperatures, adult CAT activity increased, and the adult CAT reached its peak after the larva was stressed. The female CAT activity raised at first, then decreased as the temperature increasing after high temperature continues being stressed, and reached its peak at42℃. The adult POD activity decreased after different stages of O. communa were stressed by abnormal high temperatures. After continues abnormal high temperature stressed, female POD activity decreased as the temperature increasing, and male POD activity was hardly affected. The order activity of the three enzymes was SOD> POD> CAT, the contribution rate of resistance to oxidative stress was SOD> CAT> POD, which showed that high temperature caused oxidative stress, and O. communa has the ability to resistant to oxidative stress impact caused by a temperature no more than42℃.更多还原