斜纹夜蛾人工扩繁产卵条件优化

Optimization of Oviposition Conditions for Artificial Rearing of Spodoptera litura

斜纹夜蛾卵Spodoptera litura (Fabricius)是夜蛾黑卵蜂的优势替代寄主,为提高夜蛾黑卵蜂的扩繁和应用,本试验在室内测定了斜纹夜蛾成虫产卵对4种基质、6种颜色、3种位置以及2种光暗条件的选择性。结果表明:雌成虫产卵对不同基质的选择偏好性为滤纸>无纺布>复印纸>纱布,在滤纸上的累积落卵量和产卵选择率最高,分别为2266粒和46.3%。6种颜色对雌虫产卵选择性无显著影响。雌虫偏好在基质背面产卵,其累积落卵量和产卵选择率分别为4435.17粒和92.4%,均显著高于基质侧面和正面。在光照条件下雌虫的累积落卵量为2352.8粒、产卵选择率为71.2%,明显高于黑暗条件。本研究证明产卵基质、位置和光暗条件均可显著影响斜纹夜蛾的产卵量,为大量生产寄主卵用于扩繁夜蛾黑卵蜂提供了参考依据。

Spodoptera litura(Fabricius)egg is a dominant alternative host of Telenomus remus(Nixon),a promising parasitoid of pest in China.High oviposition rate and availability of S.litura eggs are significant for improving the large-scale multiplication and application of T.remus.Therefore,the oviposition preference of S.litura for 4 substrates,6 colors,3 positions,and illumination conditions was investigated.The results showed that the preference of S.litura for egg-laying substrates ranked from high to low was filter paper>non-woven fabric>copy paper>gauze.The total number of eggs and oviposition rate on filter paper were the highest of 2266 eggs/female and 46.3%,respectively.Although the females showed no preference for colors,they preferred to oviposit on the back of the substrate.The mean number of eggs and oviposition rate on the substrate back were 4435.17 eggs/female and 92.4%,respectively,which were significantly higher than those on each of the side and the front of the substrate.In addition,compared with dark conditions,females prefer to lay eggs under bright conditions,as evidenced by higher fecundity(2352.8 eggs/female)and oviposition selection rate(71.2%)at bright than dark conditions.Collectively,these results prove that the oviposition substrate,location,and illumination conditions can significantly affect the oviposition of S.litura,which can support the development of techniques for improving mass-production and commercial application of T.remus in biological pest control.