在植物－植食性昆蟲－天敵系統(tǒng)中，化學信號被認為是最有效,、最廣泛的通訊媒介。蚜蟲在遭遇天敵或外界干擾后將,，會對同種其他個體產(chǎn)生報警反應，使其迅速逃離現(xiàn)場。這種經(jīng)長期進化的利他信息素,，在既無化學武器也沒有肢體結(jié)構(gòu)武器的情況下,，可以說是維持生存的必要條件,。
中科院動物研究所戈峰研究組以小麥主要害蟲——麥長管蚜為研究對象，模擬了分析了未來加倍的大氣CO2濃度升高條件下,，麥蚜種群和個體對蚜蟲報警激素的響應作用,。結(jié)果表明，在正常CO2濃度環(huán)境中,，報警激素對麥蚜的種群數(shù)量有顯著的抑制作用,。但在高CO2濃度環(huán)境中，無論暴露于低頻率警激素還是高頻率警激素環(huán)境中,，麥蚜的種群密度及其有翅蚜比例均不會發(fā)生改變，麥蚜種群對報警激素的脅迫作用并不敏感,。產(chǎn)生這一現(xiàn)象的主要原因是麥蚜體內(nèi)乙酰膽堿酯酶活性的降低,。
研究結(jié)果顯示,，在未來大氣CO2濃度升高的情況下,，麥蚜對報警激素的響應能力下降,，也即對外界環(huán)境脅迫的反應能力降低。
以上研究發(fā)表在國際生態(tài)學期刊Agriculture, Ecosystems & Environment上,。該文第一作者孫玉誠為動物所種群生態(tài)與全球變化研究組助理研究員,，通訊作者為戈峰研究員,。該研究工作得到了國家重大基礎研究計劃（973）,、中國科學院知識創(chuàng)新工程重要方向項目和基金委創(chuàng)新研究群體項目的資助。(生物谷Bioon.com)
生物谷推薦原文出處：
Agriculture, Ecosystems & Environment doi:10.1016/j.agee.2009.09.011
Elevated CO2 reduces the response of Sitobion avenae (Homoptera: Aphididae) to alarm pheromone
YUCHENG SUN (1) ; JIANWEI SU (1) ; FENG GE (1) ;
(1) State Key Laboratory of Integrated Management of Pest and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, CHINE
The aphid alarm pheromone (E)-β-farnesene (EβF) is an efficient signal that warns aphids of attack by natural enemies. In this field study, eight open-top chambers (OTCs) located in Beijing, China (40° 11'N, 116° 24'E) with spring wheat Triticum aestivum were used to examine the response of the grain aphid Sitobion avenae to CO2 (ambient vs. double ambient) and EβF (applied zero, two, or five times each day). We experimentally tested the hypotheses that, depending on frequency of EβF release, elevated CO2 reduces the response (in terms of population density) of S. avenae to EβF, and that lower activity of acetylcholinesterase (AChE) in S. avenae may be involved in its reduced sensitivity to EβF under elevated CO2. Numbers of S. avenae declined with increased frequency of EβF application under ambient CO2 but were unaffected by EβF application under elevated CO2. Additionally, the mean relative growth rate (MRGR) and the dry material and amino acid content of S. avenae increased with elevated CO2 but declined when with EβF application. Activities of superoxide dismutase and catalase were higher in S. avenae under elevated vs. ambient CO2. Under elevated CO2, however, AChE activity remained low when S. avenae was exposed to the lower EβF frequency, while the highest AChE activity occurred in aphids exposed to the higher EβF frequency. These results indicate that aphids become insensitive to EβF under elevated CO2, perhaps because of decreased AChE activity.
