以实验种群生命表评价六种植绥螨对西花蓟马的控制潜力

【目的】植绥螨是蓟马等害虫(螨)的重要捕食性天敌,在当前生物防治中应用广泛,本研究旨在为本地植绥螨资源的开发利用及筛选出控制西花蓟马Frankliniella occidentalis最有效的植绥螨天敌提供依据。【方法】以西花蓟马为猎物,在室内温度(25±1)℃、光照16L︰8D、相对湿度80%±5%的条件下,比较了内蒙古本地植绥螨种类有益真绥螨Euseius utilis Liang et Ke、苏氏副伦绥螨Paraseiulus soleiger Ribaga和巴氏新小绥螨Neoseiulus barkeri Hughes及目前应用的植绥螨斯氏钝绥螨Amblyseius swirskii Athias-Henriot、东方钝绥螨A.orientalis Ehara和黄瓜新小绥螨N.cucumeris Oudemans取食西花蓟马后的发育历期和生殖潜力,并组建了实验种群生命表以评价各类植绥螨的捕食潜能。【结果】有益真绥螨的日均产卵量(1.67±0.02)粒和黄瓜新小绥螨的日均产卵量(1.58±0.06)粒相近且无显著差异,仅次于斯氏钝绥螨(1.69±0.07)粒;有益真绥螨其子代雌雄性比与黄瓜新小绥螨的性比也相同(1.63︰1),低于斯氏钝绥螨(1.77︰1)和巴氏新小绥螨(1.64︰1);有益真绥螨的世代平均周期最短(T=19.36 d),内禀增长率(rm=0.16)和周限增长率(λ=1.17)均最大,种群倍增时间最短(t=4.33 d)。【结论】有益真绥螨以西花蓟马为食后种群数量增长的潜力强于其他5种植绥螨,是本地防治西花蓟马较有潜力的植绥螨种类。

Evaluation of the potential of six phytoseiid predators as biological control agents of the western flower thrip Frankliniella occidentalis

Objectives] To determine the potential for using locally dominant phytoseiid species, important biological control agents of small phytophagous herbivores such as thrips, as biological control agents of the western flower thrip, Frankliniella occidentalis. Methods]The development and reproduction of six phytoseiid species, including three local Inner Mongolian species; Euseius utilis Liang et Ke, Paraseiulus soleiger Ribaga and Neoseiulus barkeri, and three commonly used biological control agents; Amblyseius swirskii Athias-Henriot, A. orientalis Ehara and N. cucumeris Oudemans, were determined and compared. All phytoseiids were kept in a laboratory at (25±1)℃, 16L︰8D, and RH80%±5%, and fed on 1st instar F. occidentalis larvae. Life tables of the six species were compiled to evaluate their potential as biological control agents for F. occidentalis.Results] There was no significant difference between the average daily oviposition rates of E. utilis (1.67±0.02)eggs and N. cucumeris (1.58±0.06)eggs, both of which were lower than that of A. swirskii (1.69±0.07)eggs. E. utilis had the same sex ratio as N. cucumeris(1.63︰1), which was lower than that of A. swirskii (1.77︰1) and N. barkeri (1.64︰1). E. utilis had the shortest mean generation time (T=19.36 d), highest intrinsic rate of natural increase (rm=0.16) and the highest finite rate of increase (λ=1.17), resulting in the shortest population doubling time(t=4.33 d).Conclusion] E. utilis had the highest capacity for population growth among the six phytoseiid species examined, and therefore the greatest potential to be an effective indigenous biological control agent for the western flower thrip.