南方小花蝽-蚕豆-蚕豆蚜载体植物系统对茶叶害虫的控制效果

载体植物系统作为一种新型的生物防治手段，具有良好的防治效果和应用价值。蚕豆蚜Aphis fabae偏好豆科植物，对茶树安全，且作为猎物可满足南方小花蝽Orius strigicollis生长和繁殖的需要。因此本研究以蚕豆蚜作为替代猎物、蚕豆Vicia faba作为载体植物及南方小花蝽作为天敌昆虫构建“南方小花蝽-蚕豆-蚕豆蚜”载体植物系统来防治茶叶害虫。为探究该载体系统是否可有效控制茶叶害虫，本研究事先在室内比较了该载体植物系统与直接释放南方小花蝽对茶蚜Toxoptera aurnantii的防治效果；之后在田间调查中发现茶树上主要有茶蚜、茶棍蓟马Dendrothrips minowai及小贯小绿叶蝉Empoasca onukii共3种害虫混合发生，且它们均可被南方小花蝽捕食，因此在田间试验中本研究同时评价了载体植物系统及直接释放南方小花蝽对这3种害虫的防治效果。结果显示：在室内试验中，载体植物系统与直接释放南方小花蝽相比，在前3次调查中茶蚜种群数量显著降低，且虫口减退率及防治效果均显著高于直接释放南方小花蝽，其中载体植物系统对茶蚜的控制效果最高可达92.16%，而直接释放南方小花蝽对茶蚜的防治效果仅为72.25%，表明该载体植物系统有应用于田间防治茶叶害虫的潜力。在田间试验中，载体植物的布局（条状、块状及点状）对载体植物系统的防治效果无显著影响；载体植物系统与直接释放南方小花蝽均对小贯小绿叶蝉有显著的防治效果，且最高防效均在90%左右，但对茶蚜及茶棍蓟马则无明显的控制作用，表明载体植物系统与直接释放南方小花蝽均可用于茶叶害虫的防治，但在应用时需考虑到多种害虫同时发生对防治效果的影响。

Control of Tea Pests by the Banker Plant System of Orius strigicollis-Vicia faba-Aphis fabae

As a new biological control method, banker plant system is of high control efficacy and application value. Aphis fabae prefers leguminous plants and is safe to tea plant, and is a prey that can satisfy the growth and reproduction needs of Orius strigicollis. Therefore a banker plant system consisting of A. fabae as alternative prey, Vicia faba as banker plant, and O. strigicollis as natural enemy was established to control tea pests. The control efficacy of the banker plant system was compared with that of the direct release of O. strigicollis on the tea aphid Toxoptera aurnantii in the laboratory. T. aurnantii, Dendrothrips minowai and Empoasca onukii, the three principal pest species in tea plants, can all be preyed by O. strigicollis. The control efficacy of the banker plant system and the direct release of O. strigicollis on the three pests were also investigated in field experiment. The results showed that, in the laboratory experiment, the population size of T. aurnantii was significantly lower and the population decline rate and control efficacy of T. aumantii were significantly higher in the banker plant system than in the direct release of O. strigicollis in the first three surveys. The banker plant system achieved control efficacy as high as 92.16%, while the direct release of O. strigicollis reached control efficacy of only 72.25%, indicating a potential of the banker plant system to be used in the field for tea pest control. In the field experiment, the layout of the banker plants (strips, blocks and dots) showed no significant influence on the control efficacy of tea pests. Both the banker plant system and the direct release of O. strigicollis resulted in significant control of E. onukii, as high as 90%, but they did not have significant control of T. aurnantii and D. minowai. These results indicate potential of both the banker plant system and the direct release of O. strigicollis for control of tea pests, but depending on the co-occurring pest species.