大豆蚜嗅觉在选择寄主植物中的作用

OLFACTION IN HOST PLANT SELECTION OF THESOYBEAN APHID APHIS CLYCINES

大豆蚜ＡＰｈｉｓｇｌｙｃｉｎｅｓ有翅和无规孤雌生殖蚜为其寄主植物大豆叶和鼠李叶气味所引诱，而非奇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。

esults from a behavioral study by using a four-armed olfactometer (Vet et al,1983) showed that alate and apterous virginopara of Aphid glycines were clearlyattracted or arrested by volatiles from Glycine max, its secondary hostplant, andRhamnus davurica, its primary hostplant. The attractiveness of G.max was greaterthan that of R. davurica. Chemical analysis indicated that there is some differencein the volatile profiles between these two plant species. The volatiles from two non-host plant species Gossypium hirsutum and Cucumis sativa, which are the most sui-table hostplants 'of another aphid A. gossypii closely related to A. glycines, werefound to be neutral. However, the odors of Luffa cylindrica and Cucurbita pepo significantly repelled the alate virginopara of A. glycines. Thus, the olfactory response of A. glycines to these host and nonhost plants implies the evolutionary transition of A. glycines in hostplant specificity.Blending the odors from nonhost plants Gottypium hirsutum, Luffa cylindricaand Cucurbita pepo with the attractive bdor of hostplant G. max blocked theattraction of the latter to the alate virginopara of A.glycines. It thus appeared thatattraction of host plant to aphids can be disrupted by the presence of nonhost plantvolatiles which have presumably masked the host plant odor and the lack of attractionof the blended odors is caused by the change in volatile prolife.