吡丙醚的残效期及低浓度添食对家蚕结茧影响试验

The Residual Period of Pyriproxyfen and Effect of Low Concentration of Pyriproxyfen on the Cocooning of Silkworm

为探讨大田农药吡丙醚对蚕茧生产的影响,进行了低浓度吡丙醚添食试验。结果表明,吡丙醚对家蚕结茧影响较大,5龄第4天添食1.00×10^(-3) mg/L、5.00×10^(-4) mg/L、2.50×10^(-4) mg/L的吡丙醚24 h,对家蚕的结茧有影响,但到5龄第14天能够全部结茧;用1.00×10^(-2) mg/L、1.00×10^(-3) mg/L的吡丙醚,在5龄不同时间分别添食24 h,添食越晚,结茧率越低;从5龄第4天连续添食6.25×10^(-5) mg/L、3.13×10^(-5) mg/L的吡丙醚、从5龄第5天连续添食6.25×10^(-5) mg/L的吡丙醚,均可造成家蚕不结茧。吡丙醚在桑叶上的残效期超过47 d。

To understand the effect of pyriproxyfen on the growth of silkworms,a feeding test with low concentration of pyriproxyfen was carried out.Results show that the pyriproxyfen at low concentration has a great influence on the cocooning of silkworm.The cocooning of silkworm is affected by adding pyriproxyfen of 1.00×10^-3 mg/L,5.00×10^-3 mg/L and 2.50×10^-4 mg/L for 24 hours on the 4th day of the 5th instar,but all silkworms cocoon on the 14th day of the 5th instar.Adding pyriproxyfen of 1.00×10^-2 mg/L and 1.00×10^-3 mg/L at different time on the 5th instar for 24h,the cocooning rate is lowering with the later feeding.Silkworms can not cocoon by continuous feeding pyriproxyfen of 6.25×10^-5 mg/L and 3.13×10^-5g mg/L from the 4th day of the 5th instar and feeding pyriproxyfen of 6.25×10^-5 mg/L from the 5th day of the 5th instar.The residual period of pyriproxyfen on mulberry leaves is more than 47 days.