不同剂型的毒死蜱对家蚕的急性毒性评价

为明确毒死蜱对家蚕的安全性,采用浸叶法测定了4种不同剂型的毒死蜱对家蚕的毒性及其对家蚕中毒症状的观察统计。结果表明:45%毒死蜱乳油、15%毒死蜱颗粒剂、25%毒死蜱微乳剂和36%毒死蜱微囊悬浮剂对2龄家蚕96 h的LC_(50)值分别是0.176 mg/L、0.452 mg/L、1.76 mg/L和2.84 mg/L;45%毒死蜱乳油和15%毒死蜱颗粒剂为剧毒,25%毒死蜱微乳剂和36%毒死蜱微囊悬浮剂为高毒,其中微囊悬浮剂对家蚕的毒性最小。经药剂处理后,家蚕的中毒症状主要有吐液、侧卧以及体色发黑。虽然4种不同剂型中毒死蜱微囊悬浮剂毒性最小,但其仍属于高毒,因此,建议毒死蜱远离桑园及桑园附近农田使用,尤其是家蚕饲养盛期。

Acute Toxicity of Chlorpyrifos in Different Formulations

In order to evaluate the safety of chlorpyrifos to Bombyxmori L., the toxicity of chlorpyrifos to Bombyxmori L. was determinate by leaf dipped method and its toxic symptom was observed. The results showed that the 96 h LC50 of chlorpyrifos 54% EC, 15% GR, 25% ME and 36% CS were 0.176 mg/L, 0.452 mg/L, 1.76 mg/L and 2.84 mg/L, respectively. Chlorpyrifos 54% EC and 15% GR were extreme toxicity to Bombyxmori L.. Chlorpyrifos 25% ME and 36% CS were high toxicity to Bombyxmori L.. And the toxic symptoms of Bombyxmori L. were liquid secretion, side lying and blackening body color. Thus, the use of chlorpyrifos should be far away from mulberry field or nearby, especially in the breeding stage ofBombyxmori L..