大豆蚜嗅觉在选择寄主植物中的作用

大豆蚜 Aphis hlycines 有翅和无翅孤雌生殖蚜为其寄主植物大豆叶和鼠李叶气味所引诱，而非寄主植物棉花叶和黄瓜叶气味处于中性，丝瓜叶和南瓜叶气味具有明显的排斥作用。非寄主植物气味可以遮蔽寄主植物气味的引诱作用。大豆蚜触角感受器对植物气味具有嗅觉生理反应，对一些化合物的最小感觉阈值达10-5至10-6体积比浓度，表明大豆蚜触角上存在识别植物气味的嗅觉受体细胞。由此证明，嗅觉在大豆蚜选择寄主植物过程中起重要作用。

OLFACTION IN HOST PLANT SELECTION OF THESOYBEAN APHID APHIS GLYCINES

Results from a behavioral study by using a four-armed olfactometer (Vet et al, 1983) showed that Mate and apterous virginopara of Aphis glycines were clearly attracted or arrested by volatiles from Glycine max, its secondary hostplant, and Rhamnus davurica, its primary hostplant. The attractiveness of G.max was greater than that of R. davurica. Chemical analysis indicated that there is some difference in the volatile profiles between these two plant species. The volatiles from two nonhost plant species Gossypium hirsutum and Cucumis sativa, which are the most suitable hostplants of another aphid A. gossypii closely related to A. glycines, werefound to be neutral. However, the odors of Luffa cylindrica and Cucurbita peposignificantly repelled the Mate virginopara of A. glycines. Thus, the olfactory response of A. glyeines to these host and nonhost plants implies the evolutionary transition of A. glycines in hostplant specificity. Blending the odors from nonhost plants Gossypium hirsutum, Luria cylindricaand Cueurbita pepo with the attractive odor of hostplant G. Max blocked the attraction of the latter to the alate virginopara of A.glycines. It thus appeared that attraction of host plant to aphids can be disrupted by the presence of nonhost plant volatiles which have presumably masked the host plant odor and the lack of attraction of the blended odors is caused by the change in volatile prolife.