腰带长体茧蜂对亚洲玉米螟幼虫的寄生功能反应

Functional Response of Macrocentrus cingulum to Ostrinia furnacalis Larvae

为评估腰带长体茧蜂Macrocentrus cingulum对亚洲玉米螟Ostrinia furnacalis的控害潜能,在实验室条件下(湿度60%~80%,光周期16L:8D)研究了20、24、28、32℃下腰带长体茧蜂对亚洲玉米螟幼虫的寄生功能反应和20、24、28℃下腰带长体茧蜂的自身密度干扰效应。结果表明:在20~32℃内,腰带长体茧蜂对亚洲玉米螟的寄生功能反应均符合HollingⅡ型;相同温度下,随着寄主亚洲玉米螟密度的增加,腰带长体茧蜂寄生量增加,但当寄主密度增加到一定数量后,寄生量趋于稳定。24℃的寄生效能最大,20℃最小。随着寄主亚洲玉米螟密度和腰带长体茧蜂密度的增加,搜寻效应逐渐降低。采用Hessell干扰模型,发现28℃时的搜寻常数Q和干扰效应m均为最大,腰带长体茧蜂个体间的干扰效应降低了其寄生效能。

In order to evaluate the control potential of Macrocentrus cingulum to Ostrinia furnacalis,functional responses of M.cingulum to the larva of O.furnacalis at 20,24,28,32℃and the self-interference effect of M.cingulum at 20,24,28℃were examined under laboratory conditions(RH 60%-80%,16 L:8 D).The results showed that,between 20-32℃,the functional responses fitted well with the Holling typeⅡmodel.At a certain temperature,the number of parasitized larvae responded positively to host density and reached a peak when the host density increased to a certain amount.The parasitism efficiency was the largest at 24℃and the lowest at 20℃.Therefore,24℃is the suitable temperature for M.cingulum.The searching efficiency of M.cingulum decreased with the increase of O.furnacalis and M.cingulum densities.According to the Hassell model,both the searching coefficient Q and the disturbance coefficient m maximized at 28℃and minimized 20℃,indicating that the interference in M.cingulum might reduce its parasitism efficiency.