异色瓢虫4变种成虫对茶和茶蚜气味行为反应

用Y形嗅觉仪测定了异色瓢虫4个变种成虫对茶蚜利它素的行为反应,结果表明,供给茶蚜、甘蓝蚜和萝卜蚜的两两组合,茶蚜+蚜害茶梢和正常茶梢,蚜害茶梢和正常茶梢,天敌分别选择茶蚜、茶蚜+蚜害茶梢或蚜害茶梢(P<0.05);以8～9种质量梯度的茶蚜+蚜害茶梢、蚜害茶梢和茶蚜做味源,瓢虫对味源趋向率与味源质量呈Logistic曲线关系(P<0.01),其中二斑变型、显现变种和十九斑变种对茶蚜的趋向率与蚜数呈左偏的单峰曲线(P<0.01);茶蚜体表乙醚或正己烷漂洗物也有引诱力,以显明变种最敏感.

Behavior response of four Leis axyridis varieties to volatiles from tea and Toxoptera aurantii

The behavior response of the adults of four Leis axyridis varieties to kairomone from Taxoptera aurantii was determined by Y-shape olfaction instrument. The results showed that when supplied with two-two-combinations of Taxoptera aurantii, Brevicoryne brassicae and Lipaphis erysimi, tea aphids plus aphid-damaged vs. normal shoots, and aphid-damaged vs. normal shoots, Leis axyridis had a preference for tea aphids, tea aphids plus aphid-damaged tea shoots, or aphid-damaged tea shoots. There existed a Logistic curve relationship(P < 0.01) between odor source tendency rate of Leis axyridis and odor source quality, when 8-9 kinds of odor gradients including tea aphids plus aphid-damaged tea shoots, aphid-damaged tea shoots and tea aphids were used as odor sources. The tendency rates of Leis axyridis ab. bimaculata, Leis axyridis ab. conspicua and Leis axyridis var. novemdecimpunctata showed single left-tilting peak curves to the aphid number(P < 0.01). Ether and n-hexane ringes of Toxoptera aurantii body surface also showed an attraction to all varieties. Leis axyridis var. spectabilis was the most sensitive variety.