麻竖毛天牛幼虫大小对松褐天牛肿腿蜂产卵决策的影响

为探讨寄主大小对松褐天牛肿腿蜂产卵决策的影响,进而为其人工繁育和林间应用提供科学依据。本研究选取重量0.10~0.15、0.15~0.20、0.20~0.25、0.25~0.30、0.30~0.35 g的麻竖毛天牛幼虫为寄主,接入已交配的雌性松褐天牛肿腿蜂,观察并记录其寄生和产卵行为,统计子代数量和子代性比(雄性占比)。结果表明寄主大小对松褐天牛肿腿蜂的寄生率影响不明显,但可影响子代适合度;子代数量与寄主大小呈正相关关系;雄性占比随寄主个体增大而降低,但子代发育历期不受寄主大小影响。研究结果证实,寄主大小可影响松褐天牛肿腿蜂的寄生决策。

Effects of Larvae Body Size of Thyestilla gebleri on Oviposition Decision of Sclerodermus alternatusi

Effects of host size on the oviposition decision of Sclerodermus alternatusi, an ectoparasitoid of Monochamus alternatus, were determined to support artificial rearing of the parasitoid and its use in biological control. Parasitoids were artificially reared on Thyestilla gebleri larvae of different size (0.10-0.15 g, 0.15-0.20 g, 0.20-0.25 g, 0.25-0.30 g, 0.30-0.35 g) under laboratory conditions. The parasitism and oviposition behaviors were observed and the progeny number and sex ratio were recorded. The results showed that host size did not affect the parasitism rate of S. alternatusi, while did affect the progeny fitness. Progeny number was positively related with host size and the male proportion of progeny declined with the increase of host size. These findings reveal that host size does not affect the oviposition decision of S. alternatusi, but influence the progeny fitness.