新菠萝灰粉蚧不同地理种群高温胁迫的生殖差异及生理响应机制

The effect of high temperature stress on insect reproduction is the research hot of insect to environmental adaptability. It is great significance for understanding of reproduction and physiology under high temperature stress to formulate the population adaptability of Dysmicoccus neobrevipes Beardsley and its response to the global warming. There have been researched on the host selectivity of D. neobrevipes and its mechanism, but it still not unclear to understanding of reproduction and its physiological response of different geographic populations of D. neobrevipes under high temperature stress. The different geographic populations of D. neobrevipes were studied in this project base on the pre-study of effect of host plant and temperature on the development, survivorship and reproduction of D. neobrevipes. The effects of longevity, pre-lay period, reproduction of adults and survivorship of next generation of different geographic populations of D. neobrevipes under high temperature stress were observed in the laboratory. The differences of each adaptive parameters of reproduction of D. neobrevipes were analyzed. The effect of high temperature stress on enzyme activity of glutathione-S-transferases, peroxidase and phenoloxidase of different geographic populations of D. neobrevipes were measured. The responses of different geographic populations of D. neobrevipes to these enzymes were analyzed. The research results of this project may help to a good foundation for the effect of reproductive differences and physiological response mechanism of different geographic populations of D. neobrevipes under high temperature stress. It will benefit to provide technology support for further understand the population adaptability of D. neobrevipes.

高温胁迫对昆虫繁殖的影响是研究昆虫对环境适应性的热点，对高温胁迫下繁殖及生理的认识对阐明新菠萝灰粉蚧的种群适应性及其对全球变暖响应具有重要意义。目前对新菠萝灰粉蚧的寄主选择性及其机理已有相关研究，然而对新菠萝灰粉蚧不同地理种群高温胁迫的生殖影响及其生理响应的认识尚不清楚。项目在前期研究寄主和温度对新菠萝灰粉蚧繁殖影响的基础上，以新菠萝灰粉蚧不同地理种群为对象，在实验室观察高温胁迫后不同地理种群新菠萝灰粉蚧的成虫寿命、产卵前期、产卵量及后代存活率等生物学特性，分析生殖各适应性指标的差异；通过化学手段测定高温胁迫后不同地理种群新菠萝灰粉蚧的谷胱甘肽-S-转移酶、过氧化物酶和酚氧化酶的活性，分析不同地理种群新菠萝灰粉蚧对这些酶的响应。项目有助于阐明新菠萝灰粉蚧不同地理种群在高温胁迫下的生殖影响和生理响应机制，为进一步理解新菠萝灰粉蚧的种群适应性提供科技支撑。

开展高温胁迫对新菠萝灰粉蚧不同种群繁殖及生理的影响研究对阐明该粉蚧的种群适应性及其对全球变暖响应具有重要意义。本项目在实验室观察了高温胁迫（35℃、38℃、41℃、44℃）后新菠萝灰粉蚧不同种群（广西、广东、海南和云南）的生殖生物学特性，测定了高温胁迫后粉蚧不同种群的谷胱甘肽-S-转移酶（GST）、过氧化物酶（POD）和酚氧化酶（PO）的活性；分析短时高温胁迫对广西种群粉蚧不同发育阶段死亡率的影响。结果表明，高温胁迫对新菠萝灰粉蚧不同种群的雌成虫寿命、后代雌雄性比和存活率、GST和PO活性均有显著影响，而对部分种群的雌成虫产若虫前期和产若虫量、POD活性有显著影响。高温胁迫下，新菠萝灰粉蚧广东、海南、云南种群的产若虫前期随温度上升呈先缩短后延长的趋势；云南种群的雌成虫寿命均短于常温26℃的雌成虫寿命，其他种群的雌成虫寿命随着温度升高呈先缩短后延长的趋势；海南种群41℃的产若虫量显著高于常温26℃的产若虫量，而云南种群41℃的产若虫量显著低于常温26℃的产若虫量。随着温度升高，该粉蚧GST、PO的活性分别以先升后降、先降后升再降的变化来响应其对高温胁迫的影响；而海南和云南种群粉蚧的POD活性以先升后降的变化来响应其对高温胁迫的影响。研究发现新菠萝灰粉蚧在47℃胁迫2h后的死亡率为100%；短时高温锻炼不能增强该粉蚧的高温胁迫耐受性。本研究结果为阐明新菠萝灰粉蚧不同地理种群在高温胁迫下的生殖影响和生理响应机制及其种群适应性提供参考。