甘蓝夜蛾赤眼蜂滞育研究

Study on the Diapause of Trichogramma brassicae

寄生在麦蛾(Sitotroga cerealella)卵内的甘蓝夜蛾赤眼蜂(Trichogramma brassicae)在河北衡水地区田间能进入滞育越冬。当日均温度从15℃降低到5℃,田间诱导滞育率降低,多数个体在进入滞育虫态前死亡。实验室,采用变温和恒温方法均能诱导甘蓝夜蛾赤眼蜂滞育,在11℃恒温诱导卵期和前期幼虫赤眼蜂30d滞育率分别达到84％和82.5％;10℃恒温诱导前期幼虫和中期幼虫赤眼蜂30d,滞育率达到92.5％。

Trichogramtna brassicae parasitized in Sitotroga cerealella eggs could be induced into diapause in winter time in Hengshui, Hebei. When the average temperature was reduced from 15 to 5 ℃, the rate of diapause was also decreased, and most of the parasite were dead before entering the diapause stage. In laboratory, T. brassicae were induced into diapause by both constant low temperature and day /night alternating temperature.