Safety of 1% Matrine-azadirachtin EC on Mulberry and Silkworm

In order to investigate the high efficiency pesticide against mulberry pests and safety to silkworm and mulberry,the harm to mulberry and residual toxicities to silkworm of different concentration(10,20,40 mg /L) of 1% matrine-azadirachtin EC were evaluated when sprayed after 1 d,3 d,5 d,7 d,10 d and 15 d. The results showed that it was not phytotoxic to mulberry in all treatments. Silkworm was found poisoning death that fed the leaves treated by 40 mg / L of 1% matrine-azadirachtin EC after 3 d,and other showed refusing to eat food. Compared with CK( water treatment),the 4th and 5th instar were prolonged 0. 5 d to 1. 5 d that fed the leaves treated after 3—7 d,and the developmental duration of survival larvae,the weight of dormant silkworm,the weight of mature silkworm,cocoon weight,cocoon shell weight in treatments of 1% matrine-azadirachtin EC showed no significant difference compared with CK when sprayed after 15 d. Therefore,1% matrine-azadirachtin EC can be used to control pests in mulberry field,and the safety interval on silkworm was more than 15 d.