外源茉莉酸甲酯处理茶树对茶尺蠖幼虫生长的影响

Effect of Exogenous MJA Treatment of Tea Plants on the Growth of Geometrid Larvae

研究了应用外源茉莉酸甲酯处理茶树后,对茶树叶片中脂氧合酶、多酚氧化酶和蛋白酶抑制素活性,以及对茶尺蠖幼虫中肠蛋白酶活性和生长的影响。结果表明,应用外源茉莉酸甲酯喷雾法或暴露法处理茶树,都能够诱导茶树叶片脂氧合酶、多酚氧化酶和蛋白酶抑制素活性增加,茶尺蠖幼虫中肠强碱性类胰蛋白酶活性和类胰凝乳蛋白酶活性受抑制,但弱碱性类胰蛋白酶活性未受抑制,从而导致茶尺蠖幼虫中肠内各种蛋白酶间的协调性遭到破坏,生长受阻,这可能是茉莉酸甲酯诱导茶树对茶尺蠖幼虫产生直接抗性作用的一种机制。

The effect of tea plants Camellia sinensis induced by exogenous methyl jasmonate (MJA) on lipoxygenase (LOX), polyphenol oxidase (PPO) and proteinase inhibitor (PI) activity in the leaves of tea plants, as well as the growth and midgut proteinase activity of geometrid Ectropis obliqua larvae were studied. MJA significantly induced LOX, PPO and PI activity in tea leaves of tea plants. When geometrid larvae have fed on leaves of tea plants treated with MJA, the activities of the high alkaline trypsin-like enzyme and chymotrypsin-like enzyme in their midgut were significantly inhibited, but the activities of the low alkaline trypsin-like enzyme in their midgut were unaffected, leading to imbalance between different types of proteinase activity in the midgut of the larvae and in turn, the growth were inhibited. This chain of responses may be an important mechanism of the direct resistance induced by MJA-treatment of tea plant on geometrid larvae.