茶园新天敌绿点益蝽的初步研究

Picromerus viridipunctatus Yang:a new natural enemy in tea plantations

绿点益蝽Picromerus viridipunctatus是茶园中新发现的一种捕食性天敌。为探明其生防潜力,通过室内饲养和观测,对其生物学习性和捕食行为开展了研究。结果表明,绿点益蝽在杭州一年发生4代,以成虫越冬;若虫共有5龄。在7月-11月自然温度条件下,卵期、若虫期和成虫期分别为9.1~9.7、23.4~28.0、22.5~26.6 d。单雌平均产卵量133粒,卵平均孵化率55.6%。若虫和成虫均能捕食多种茶园鳞翅目害虫,目前已明确的有茶尺蠖、灰茶尺蠖、茶用克尺蠖、茶蚕、茶刺蛾和茶斑蛾等;成虫对4龄灰茶尺蠖的日捕食量为5.5头。绿点益蝽在茶园具有较好的应用潜力。

It is reported for the first time that Picromerus viridipunctatus was a natural enemy discovered in tea garden of Zhejiang province.In order to explore its biocontrol potential,its biological characteristics and predatory behavior were investigated through indoor rearing and observation.The results showed that P.viridipunctatus had four generations a year in Hangzhou,and overwintered as adults.Nymphs have five instars.Under natural temperature conditions from July to November,the developmental duration of egg,nymph and adult stages were 9.1-9.7 days,23.4-28.0 days and 22.5-26.6 days,respectively.The fecundity of each female was 133 eggs,and the average hatching rate of eggs was 55.6%.Both nymphs and adults can prey on a variety of lepidopterous pests in tea plantations,including Ectropis obliqua,E.grisescens,Junkowskia athleta,Andraca bipunctata,Phlossa fasciata and E.aedea.The daily predation of adults on the 4th-instar larvae of E.grisescens was 5.5 individual.Thus,P.viridipunctatus had potential to be applied in tea plantations.