番茄枝叶提取物对菜粉蝶产卵的忌避作用

生物测定结果表明,番茄枝叶的甲醇和水溶性乙醇提取物(简称Em、Em-eEe)对菜粉蝶均有显著的产卵忌避作用;其中Ee、Em—e和Em第1天的产卵忌避率分别为87.4%、85.1%和50.5%,均达到差异显著水平。番茄枝叶乙醇提取物(Ee)不仅能显著地忌避菜粉蝶产卵,而且还强烈地干扰其产卵行为。在网室中,Ee的3个剂型试验结果表明,只有剂型“Ee+0.1%吐温—80”对莱粉蝶的产卵忌避率达到差异显著水平,第6天的忌避率仍达35.4%。

ACTIVITY OF TOMATO PLANT EXTRACTS IN DETERRING OVIPOSITION OF CABBAGE BUTTERFLY, PIERIS RAPAE

Semiochemicals perform the key physiological functions in the course of interactions between insects and plants. Bioassay studies showed that the avoidance of tomato plant from oviposition by cabbage butterfly was proved to be attributed to the presence of water-soluble deterrent which could be extracted by ethanol. Oviposition deterrent indices (ODI) of the ethanol extract (Ee) were 87.4 % and 80.9 % respectively in the first day and third day after treatment, both were statistically significant . The active water-soluble fractions when applied on cabbages not only significantly reduced the amount of eggs laid on the cabbage leaves, but also strongly disturbed their normal oviposition behavior in contrast to the controls. Net-house tests showed that a formulation of the active water-soluble components with Tween-80 (Ee+0.1% Tween-80) may be hopeful to be developed as an 0viposition-deterrent which keeps effective for more than a week when applied on cabbages.