苍耳甾醇类物质对小菜蛾的产卵及趋向行为选择的影响

Effects of sterols from Xanthium sibiricum on oviposition of Plutella xylostella and its behavioral choice

通过活性成分的跟踪分离和生物活性测试,研究从苍耳Xanthium sibiricum分离提纯的甾醇成分对小菜蛾Plutella xylostella的产卵忌避活性及其行为选择的影响。结果显示,分离出的5个结晶组分中,结晶组分V对小菜蛾的产卵忌避活性最高,处理后24h、48h和72h的选择性产卵忌避率分别达75.76%、85.45%和65.85%,结晶组分Ⅳ次之,分别为42.10%、39.33%和47.65%,其它结晶组分活性很弱或无产卵忌避性。用Y-型管测试苍耳结晶组分对小菜蛾成虫趋向行为选择的影响,结果发现组分V对小菜蛾雌、雄成虫均有明显的负趋向作用,选择系数分别为0.29和0.35;组分Ⅳ次之;同时,小菜蛾对所测试各结晶组分的选择在雌虫和雄虫间差异不显著。GC-MS分析,苍耳结晶组分V和Ⅳ均主要含有豆甾醇和谷甾醇,以及极少量的菜油甾醇,但各成分所占比例有差异。

The active components against Plutella xylostella were extracted from Xanthium sibiricum,using column chromatography and recrystallization methods,to study their oviposition deterrent effect and negative tropism of behavior choices on P.xylostella adults.The results showed that among the isolated five components,the Component V showed highest oviposition deterrent rate on P.xylostella adult with 75.76%,85.45% and 65.85% after treated 24 h,48 h and 72 h,respectively.Followed with the Component Ⅳ of 42.10%,39.33% and 47.65%,respectively.Others showed very low or no oviposition deterrent activity.Then,Y-Tube was used to test the behavior choices tropism of P.xylostella adults,and the Component V showed the highest negative trend effect on P.xylostella adults also,with the Selevtive Index of 0.29 and 0.35 for female and male,respectively.Furthermore,behavior choice tropism of female and male of the moth was similar,and no significant difference between them.Finally,chemical composition of the Component V and Ⅳ from X.sibiricum were analyzed by using gas chromatography-mass spectrum,and were found that they primarily contain stigmasterol,sitosterol,and some small quantities of campesterol,but the content of the three components was different between them.