茉莉酸甲酯处理对棉铃虫生长和解毒能力的影响

Effects of methyl jasmonate treatment on the growth and detoxifying abilities of Helicoverpa armigera( Lepidoptera: Noctuidae)

【目的】为明确茉莉酸甲酯(methyl jasmonate,MeJA)的不同处理方式对昆虫生长和解毒代谢能力的影响,以及MeJA熏蒸处理昆虫对植物防御和昆虫解毒代谢之间关系的影响。【方法】本文比较了取食MeJA和MeJA熏蒸等两种处理对棉铃虫Helicoverpa armigera 3龄末幼虫生长和解毒代谢酶活性的影响,并系统研究了经MeJA熏蒸处理的棉铃虫3龄末幼虫,再取食经MeJA喷雾处理的棉叶,其中肠解毒酶活性的变化。【结果】取食MeJA和MeJA熏蒸两种不同处理,对棉铃虫幼虫的生长及解毒能力的影响有所不同。取食含2.9μg/g MeJA的人工饲料显著抑制了棉铃虫的生长,同时诱导棉铃虫幼虫P450活性增加了1.92倍,而MeJA熏蒸虽然没有影响棉铃虫幼虫的生长,但MeJA熏蒸处理使棉铃虫幼虫P450活性和羧酸酯酶活性分别增加了2.94倍和1.16倍。经MeJA熏蒸处理后的棉铃虫幼虫,再取食正常的或经MeJA喷雾处理的棉叶,其幼虫P450活性显著增加,其中经MeJA熏蒸处理的棉铃虫,再取食经MeJA喷雾处理的棉叶,其P450酶显示了最高活性。【结论】MeJA熏蒸处理棉铃虫,不仅使棉铃虫中与P450酶相关的解毒能力显著增加,而且增加了棉铃虫对于MeJA所诱导的棉花防御反应的解毒能力。

【Aim】To clarify the effects of methyl jasmonate （MeJA） treatments on the growth and detoxifying metabolic abilities of insects, and the effects of MeJA fumigation on the relationship between plant defense and insect detoxifying metabolism. 【Methods】 The influences of feeding MeJA and MeJA fumigation on the growth and the activities of detoxifying enzymes in the late 3rd instar larvae of H. armigera were examined, and the changes of detoxifying enzymes in H. armigera larvae, which fed the MeJA-sprayed cotton leaves after fumigation with MeJA, were also studied. 【Results】 Feeding MeJA and MeJA fumigation produced different effects on the growth and the detoxifying abilities of H. armigera larvae. Feeding the artificial diet containing 2.9 μg/g MeJA inhibited the growth of H. armigera larvae, and induced 1.92-fold increase in P450 activities. However, after fumigation with MeJA, no significant effects on the growth of H. armigera larvae were observed, while the activities of P450 and carboxylesterases （CarEs） increased to 2.94 and 1.16 times as high as the control, respectively. The P450 activities in H. armigera larvae, which experienced MeJA fumigation firstly and then fed the normal or MeJA-sprayed cotton leaves, were significantly induced, and H. armigera larvae, which fed the MeJA-sprayed cotton leaves after fumigation with MeJA, exhibited the highest P450 activity. 【Conclusion】MeJA fumigation induces the P450 related detoxifying abilities, and increases the detoxifying abilities in H. armigera against cotton defense responses induced by MeJA.