茶刺蛾危害诱导茶树挥发物释放变化的研究

Study on Change in Tea Plant Volatile Damaged by Iragoides fasciata Moore(Lepidoptera: Eucleidae)

茶园观察发现,茶刺蛾危害的茶园的棒须刺蛾寄蝇数量明显多于未危害的茶园。推测茶树被茶刺蛾危害后释放了特定的信号物质,这些物质在棒须刺蛾寄蝇寄主定位中起着关键的作用。为了证实这一猜想,我们研究了茶刺蛾危害对茶树挥发性有机物释放的影响。未受茶刺蛾危害的枝叶有挥发性有机物74种组分。与未受茶刺蛾危害枝叶的挥发物组分相比较,受害后酯类、醛类和烃类的种类数量和所占相对含量都有显著变化。醇、杂环化合物、醚和有机酸类化合物在种类数量和相对含量上变化不大。受害后,4-异丙基甲苯、蒎烯、1-乙基-2,4-二甲基苯、4-乙基甲苯、3-乙基-甲苯、6-甲基庚烯[5]酮[2]和1,2,4-三甲基苯的相对含量显著增加。新产生54种化合物,其中烯烃14种,芳香烃12种,酯8种,烷烃8种,酮5种,醇3种,醛2种,有机酸和杂环类各1种。值得注意的是受害后萜类化合物的种类数量和相对含量均有显著的变化,暗示这些化合物可能在棒须刺蛾寄蝇的寄主寻找过程中发挥作用。研究结果为筛选引诱天敌昆虫的化学信息素,并应用其防控茶刺蛾的研究奠定一定的基础。

Observed in the tea garden, we found that the number of Chaetexorista palpis Chao in the tea plantations where tea plants were damaged by tea slug moth was significantly more than those undamaged. We speculate that tea plant would release specific signal substances which play a key role in host location（especially long distance）by C. palpis. In order to confirm this conjecture, the effect of the damaging of tea slug moth on the volatile organic compounds （VOCs）of tea plant was studied. The results indicated that a total of seventy-four components were identified in the undamaged twigs and leaves. Compared with the undamaged twigs and leaves, the number and relative content of ethers, aldehydes, and hydrocarbons changed evidently, while those of alcohols, heterocyclic compounds, ethers and organic acid compounds had little change. After damage, the relative content of 4-cymene, pinene, 1-ethyl-2,4-dimethylphenoxy, 4-ethyltoluene, toluene-ethyl- 6-methyl- heptene [5]ketone [2] and 1,2,4- trimethylbenzene increased significantly. fifty-four new compounds were founded in the damaged ones, including of fourteen alkenes, twelve aromatic hydrocarbons, eight esters, eight alkanes, five ketones, three alcohols, two aldehydes, one heterocyclic and one organic acid. It is worth noting that the number and relative content of terpenoids significantly changed, suggesting that these compounds maybe play an important role on the host finding by C. palpis.The results can lay a foundation for screening infochemicals which can be used as a lure for natural enemies of insects and applied to control I. fasciata Moore.