南方小花蝽在不同试验空间对西花蓟马的捕食及搜寻效应

【背景】南方小花蝽是一类很有利用前景的捕食性天敌,而有关其在不同捕食空间下对我国局部地区暴发成灾的重要入侵害虫西花蓟马捕食控制效能的研究较少。【方法】在实验室条件下比较研究了南方小花蝽成虫在不同试验空间对西花蓟马成虫、若虫的捕食选择性、捕食功能反应与搜寻效应。【结果】南方小花蝽成虫对西花蓟马若虫的捕食选择性强于成虫;在相同的试验空间,南方小花蝽成虫的日均捕食量随猎物数量的增加而增大,其对西花蓟马成虫和若虫的捕食量在猎物数量为每指形管中60头时最大,分别为15.90和19.30头;而搜寻效应随猎物数量的增加而降低。在各供试条件下,捕食功能反应均符合Holling Ⅱ型方程;南方小花蝽成虫在小饲养容器中对西花蓟马若虫的瞬时攻击率最大,为1.2794;而在大饲养容器中对西花蓟马成虫的瞬时攻击率最小,仅为0.3506,其处理1头西花蓟马成虫的时间约需0.0402d,而处理1头若虫的时间仅需0.0242d。在相同的猎物数量下,南方小花蝽成虫在大饲养容器中对西花蓟马的日均捕食量均低于其在小饲养容器中对西花蓟马的日均捕食量。【结论与意义】南方小花蝽对西花蓟马有很强的捕食效能,对西花蓟马的种群消长具有一定控制作用。本研究旨在为应用南方小花蝽防治西花蓟马积累资料,同时为西花蓟马的综合治理奠定理论基础。

Prey preference and searching efficiency of Orius similis on Frankliniella occidentalis in different experimental space

Background] Orius similis Zheng is a predatory natural enemy of many insect pests and has significant exploitation and utilization potential.There are,however,very few studies on its efficiency and control effects on the invasive insect pest,the western flower thrips,Frankliniella occidentalis（Perganda）,thus limitings its use as a biological control agent.Method] Prey preference,functional response and searching efficiency of O.similis adults on adults and nymphs of F.occidentalis in different experimental spatial arrangements were studied in the laboratory.Result] Adults of O.similis preferred nymphs to adults of F.occidentalis.At the same experimental space,the number of daily prey consumption increased with increasing the prey density at 60 prey individuals per finger tube,the maximum consumption number of O.similis adult for the adult and nymph of F.occidentalis were 15.9 adults and 19.3 nymphs of the prey,respectively.However,the searching efficiency of O.similis adult decreased with increasing density of F.occidentalis.The functional response of O.similis adults could be described by a type Ⅱ Holling equation.The instantaneous attack rate of O.similis adult to nymphs of F.occidentalis was 1.2794 in small rearing bottle,whereas the instantaneous attack rate of O.similis adult to adult of F.occidentalis is only 0.3506 in large rearing bottle;the shortest time for a O.similis adult to treat with a F.occidentalis nymph is 0.0242 d,whereas it need 0.0402 d for treating with a F.occidentalis adult.In the same density of F.occidentalis,the average number of daily prey consumption of O.similis adults in large rearing bottle was lower than those in small rearing bottle.Conclusion and significance] O.similis has strong prey efficiency on F.occidentalis and has control effect on the western flower thrips.This study aims to accumulate data for biological control of F.occidentalis,and laid a foundation for Integrated Pest Management of F.occidentalis.