苦豆子生物碱对柳蓝叶甲产卵行为的影响

Effects of Alkaloids from Sophora alopecuroides on Oviposition Behavior of Plagiodera versicolora

在实验室条件下研究苦豆子生物碱对柳蓝叶甲产卵行为的影响。结果表明:苦豆子不同生物碱对柳蓝叶甲成虫的毒力不同,因而对柳蓝叶甲产卵行为的影响也不同。在选择性取食条件下,5mg·mL-1苦豆子生物碱即对柳蓝叶甲成虫产卵具有强烈的抑制作用,槐果碱、苦参碱、苦豆碱和总碱对柳蓝叶甲成虫产卵抑制率分别为61.2%,61.3%,46.3%和53.2%。槐定碱和氧化苦参碱对产卵的抑制效果较差,抑制率仅为6.4%和5.3%。在选择性条件下虽然苦参碱对柳蓝叶甲的产卵驱避率高达54%,但各生物碱单体之间无显著差异。在非选择性取食条件下,苦豆子生物碱对柳蓝叶甲成虫产卵的抑制作用更为强烈,用总碱、苦豆碱、氧化苦参碱和槐定碱处理后的叶片饲喂12天,其产卵抑制率平均分别为82.2%,74.4%,55.6%和33.6%。当用毒力较弱的氧化苦参碱、苦豆碱或槐定碱处理时,柳蓝叶甲雌虫倾向于把卵产在非生物碱处理的叶片上;这些生物碱处理对柳蓝叶甲卵块大小无显著影响但产卵量明显受抑制。当用毒力较强的槐胺碱或槐果碱处理时,柳蓝叶甲的产卵量和卵块大小均受明显影响。

The effects of alkaloids from Sophora alopecuroides on oviposition of Plagiodera versicolora, an important insect pest attacking poplar trees, were studied using leaves of young poplar as oviposition substrates. Results showed that different alkaloids from S. alopecuroides had different toxicity to the P. versicolora adults, causing different effects on oviposition behavior. In selective feeding condition, 5 mg·mL -1 of sophocarpine, matrine, aloperine and total alkaloids strongly inhibited oviposition and the inhibition rates were 61.2% ,61.3% ,46.3% and 53.2% respectively, while the same dose of sophoradine and oxymatrine had limited effects on oviposition inhibition （ inhibition rates were 6.4% and 5.3% , respectively）. Matrine in 5 mg·mL-1 also had a high oviposition repellent rate （54%） while the other alkaloids monomers did not show significant differences in the repellent rate of oviposition. In non-choice test, the inhibition rates of oviposition, when treated （long-term, 12 days） with the total alkaloids, aloperine, oxymatrine and sophoradine, were higher than those in choice test, reaching to 82.2% , 74.4% , 55.6% and 33.6% , respectively. When treated with oxymatrine, aloperine or sophoradine, female P. versicolora preferred depositing eggs on non-alkaloids treated leaves over alkaloids treated leaves. Although clutch size was not affected, female egg production was significantly inhibited after being treated with these low toxic alkaloids. The fecundity and clutch sizes deposited by female P. versicolora were also affected significantly when treated with stronger toxic alkaloids such as sophoramine or sophocarpine.