9种杀菌剂对家蚕的急性毒性及风险性评价

Acute Toxicity and Risk Assessment of 9 Fungicides to Larvae of Bombyx mori

采用食下毒叶法,测定了生产上常用的9种杀菌剂对家蚕的急性毒性,系统观察了杀菌剂处理家蚕后的中毒症状,并作风险性评价。结果表明,10%苯醚甲环唑WG和42.4%唑醚·氟酰胺SC对家蚕48 h的LC_(50)值分别为23.344和101.324 mg/L,属中毒级,对家蚕具有极高风险性;22.5%啶氧菌酯SC、80%戊唑醇WP、300 g/L苯甲·丙环唑EC、70%丙森锌WP、80%代森锰锌DP、50%醚菌酯WG和500 g/L百菌清SC对家蚕48 h的LC_(50)值均大于200 mg/L,属低毒级,22.5%啶氧菌酯SC对家蚕具有高风险性,其他6种药剂对家蚕具有中等风险性至低风险性;家蚕接触农药后中毒症状主要包括拒食、吐液、乱爬、体缩/体软、身体扭曲呈"S"或"C"形等,但家蚕对不同杀菌剂也表现出异样的症状。

Acute toxicities of 9 commonly fungicides to silkworm （Bombyx mori） were evaluated in the laboratory using the leaf dipping method, and the toxic symptoms of silkworms after treatment of pesticides were systematically observed, and the risk assessment for these fungicides was also made accordingly. The test results indicated that the 48 h-LC50 values of 10 % WG Difenoconazole and 42.4 % SC pyraclostrobin · flutolanil were 23. 344 and 101. 324 mg/L, which belonged to moderate toxicity and extreme risk. And the 48 h-LC50 values of 22.5 % SC picoxystrebin, 80 % WP tebuconazole, 300 g/L EC difenoconazole · Propiconazol, 70 % WP prepineb, 80 % DP mancozeb, 50 % WG kresoxim-methyl, 500 g/L SC chlorothalonil were higher than 200 mg/L, which belonged to Slight toxicity, and the acute risk of 22.5 % SC Picoxystrobin was high, the acute risk of the other six fungicides were intermediate and slight. The general poisoning symptoms of fungicides treatment in silkworms were food rejection, vomiting, crawling, shorting / weak of body, and stiffness of body in the shape of an ＇S＇or ＇C＇, etc.. However, different kinds of fungicides led to different symptoms in silkworm.