百草枯水剂及9种替代产品对家蚕的急性毒性与安全性评价

Acute Toxicity and Risk Assessm ent of Paraquat Aqueous Solution and Its 9 Alternative Products to Bombyx mori

百草枯水剂是桑园等经济林园常用的除草剂。采用浸叶法测定百草枯水剂及其替代产品百草枯膏剂、可溶性粒剂、可溶性胶剂、颗粒剂与草铵膦铵盐水剂、草甘膦异丙胺盐水剂、草甘膦·草铵膦水剂、草甘膦铵盐可溶性粒剂、草甘膦水剂对家蚕的急性毒性,并进行风险性评价,为桑园除草安全用药提供试验依据。结果表明:百草枯水剂及上述9种替代产品对家蚕的急性毒性均为低毒,对家蚕2龄幼虫的96 h LC50分别为2 575.163、408.247、539.030、276.802、1 917.195、306.395、882.738、1 119.454、1 135.177和2 596.773 mg/L。鉴于灭生性除草剂的田间施用浓度较高,仅百草枯颗粒剂对家蚕的安全性为中等风险,草甘膦水剂对家蚕的安全性为中高风险,而百草枯可溶性胶剂、草铵膦铵盐水剂、草甘膦异丙胺盐水剂和草甘膦铵盐可溶性粒剂对家蚕的安全性均为高风险。依据试验结果认为,生产上选用百草枯水剂替代产品作为桑园除草剂时应极为慎重。

Paraquat is the common herbicides used in mulberry fields and other economic forest gardens. Leaf dipping method was applied to determine the acute toxicity of paraquat aquous solution and its nine alternative products,namely paraquat mastic,soluble granule,soluble glue,granule and glufosinate-ammonium aqueous solution（ AS）,glyphosate isopropamide salt AS,glyphosate·glufosinate AS,glyphosate-ammonium soluble granule and glyphosate AS,to silkworm（ Bombyx mori） larvae and also to assess the ecological risk of these weedicides so as to provide references for safe use of weedicides in mulberry field. The results showed that,paraquat aqueous and all 9 alternative products were of low toxicity to silkworm,with 96 h LC50 of 2 575. 163,408. 247,539. 030,276. 802,1 917. 195,306. 395,882. 738,1 119. 454,1 135. 177 and 2 596. 773 mg / L to the 2nd instar silkworm larvae respectively. However,due to the high application dosage for above sterilant herbicides,only paraquat granule had moderate risk to silkworm,glyphosate AS had middle to high risk,whereas paraquat glue,glufosinate-ammonium AS,glyphosate isopropamide salt AS and glyphosate-ammonium soluble granule all had high risk. Therefore,high attention should be paid when the alternative products of paraquat aqueous solution were applied in mulberry field.