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烟草Nicotiana tabacum L.是棉铃虫Helicovepa armigera (H黚ner)、烟青虫Helicoverpa assulta (Guen雃)和斜纹夜蛾Spodoptera litura (Fabricius) (Lepidoptera, Noctuidae)的共同寄主. 用HPLC测定烟草叶片烟碱含量, 比较了3种昆虫取食以及机械损伤模拟取食对烟草诱导防御反应的差异. 结果表明, 棉铃虫、烟青虫取食以及机械损伤后用它们的下唇腺提取液处理烟草叶片, 都能够抑制损伤对烟草烟碱的诱导; 在烟草叶片的机械损伤部位涂抹黑曲霉Aspergillus niger葡萄糖氧化酶也能够抑制损伤对烟草烟碱的诱导. 相反, 斜纹夜蛾取食或机械损伤后用该幼虫下唇腺提取液处理烟草叶片, 都能够促进损伤对烟草烟碱的诱导; 而加热变性后的斜纹夜蛾下唇腺提取液同样能够促进机械损伤对烟草烟碱的诱导. 由此可见, 昆虫下唇腺中的物质对烟草烟碱的诱导反应有着重要作用. 进一步检测发现, 棉铃虫和烟青虫下唇腺中都存在葡萄糖氧化酶活性, 且棉铃虫下唇腺中该酶的活性显著高于烟青虫的, 而在斜纹夜蛾下唇腺提取液中没有检测到该酶活性; 葡萄糖氧化酶在棉铃虫中主要存在于下唇腺, 其最适pH为7.0, D-葡萄糖是它的最适底物; 在幼虫发育期内, 棉铃虫下唇腺中葡萄糖氧化酶的活性是动态变化的, 在每一龄期幼虫取食最活跃的时期该酶
Tobacco Nicotiana tabacum L. is a co-host of Helicovepa armigera (H 黚 ner), Helicoverpa assulta (Guen 雃) and Spodoptera litura (Fabricius) (Lepidoptera, Noctuidae). The nicotine content of tobacco leaves was determined by HPLC , And compared the differences between three kinds of insects feeding and mechanical injury simulated feeding on tobacco-induced defensive responses.The results showed that tobacco bollworm, tobacco budworm feeding and mechanical injury with their lower labial gland extract treatment of tobacco leaves, can Inhibition of tobacco nicotine induction by injury; application of Aspergillus niger glucose oxidase to the mechanical injury site of tobacco leaves also inhibited the induction of tobacco nicotine damage. In contrast, Spodoptera litura Lip gland extract treatment of tobacco leaves, can promote damage to tobacco nicotine induction; and heat denaturation of Spodoptera litura extract can also promote mechanical damage on tobacco nicotine induction.Thus, under the insect The material in the labial glands plays an important role in the induction of nicotine in tobacco, and further tests found that cotton bollworm and tobacco smoke Glucose oxidase activity in the lower gland, and the activity of the enzyme in the lower gland of the bollworm was significantly higher than that of the tobacco budworm, whereas no activity was detected in the lower gland extract of Spodoptera litura; It is mainly found in the lower gland of Helicoverpa armigera, its optimum pH is 7.0 and D-glucose is the most suitable substrate for it. The activity of glucose oxidase in the lower gland of Helicoverpa armigera larvae is dynamic during larval development During each period of larval feeding the most active period of the enzyme