双七瓢虫对蚜虫捕食作用

【目的】研究双七瓢虫Coccinula quatuordecimpustulata(Linnaeus)对蚜虫的捕食习性,为其保护利用提供依据。【方法】采用13种蚜虫分别饲喂双七瓢虫1~4龄幼虫及成虫,观察记录24 h的捕食数量;选取大豆蚜Aphis glycines Matsumura、豌豆蚜Acyrthosiphon pisum(Harris)和白杨毛蚜Chaitophrus populeti(Panzer)分别对双七瓢虫进行饲养,记录瓢虫发育历期。【结果】双七瓢虫对供试的13种蚜虫捕食数量存在显著差异,其嗜食程度依照对蚜虫的日捕食生物量依次为:大豆蚜、菊小长管蚜Macrosiphoniella sanborni(Gillette)、月季长管蚜Sitobion rosivorum(Zhang)、豌豆蚜、甘蓝蚜Brevicoryne brassicae(Linnaeus)等;用大豆蚜和豌豆蚜饲养,双七瓢虫各虫态发育历期较短,用白杨毛蚜饲养则发育历期较长,3种蚜虫饲养的双七瓢虫,蛹均能正常羽化。【结论】双七瓢虫对供试蚜虫均有捕食行为,但捕食量存在明显差异;不同蚜虫对双七瓢虫的发育历期具有一定影响。

Predation by Coccinula quatuordecimpustulata on aphids

Objectives] To assess the potential of Coccinula quatuordecimpustulata （Linnaeus） as a biological control for aphids. Methods] lst-4th instar larvae and adult C. quatuordecimpustulata vgere fed on 13 species of aphids and the daily maximum predation rate recorded. The developmental duration of C. quatuordecimpustulata larvae when fed either Aphis glycines Matsumura, Acyrthosiphon pisum （Harris） or Chaitophrus populetii （Panzer） was compared. ]Results] The daily maximum predation rate varied significantly with the species of aphid provided as prey. The food preferences of C. quatuordecimpustulata were identified by the biomass consumed daily and were, in descending order： A. glycines, Macrosiphoniella sanborni （Gillette）, Sitobion rosivorum （Zhaug）, A. pisum, Brevicoryne brassicae （Linnaeus）, etc. All pupae underwent eclosion normally. However, the developmental duration of larvae was shorter when fed on A. glycines and A. pisum than when fed on C. populetii. ]Conclusion] C. quatuordecimpustulata can prey on all 13 aphid species with which it was tested. However, its predation rates and developmental duration varied significantly with aphid prey species.