4种农药对家蚕的毒性评价和中毒症状观察

采用食下毒叶法，测定了4种农药对家蚕的毒性，观察了4种农药处理2龄家蚕后的中毒症状。结果表明，3种杀虫剂除虫菊素5％乳油、吡虫啉2．5％可湿性粉剂和氯胺磷20％乳油的LC50值均在0．1～10mg／L之间，对家蚕属高毒级，有极高风险性：杀菌剂苯醚．丙环唑300g／L乳油的LC50值为5．60×10^2mg／L，对家蚕属低毒级，风险性相对较低。观察了中毒症状，3种杀虫剂引起家蚕中毒症状较突出，易于辨别，杀菌剂引起的家蚕中毒症状较轻微。桑园及附近用药时需特别注意避免喷施3种杀虫剂。

Toxicity Evaluation of Four Formulation to Bombyxmori and Observation of Toxi Symptoms

The acute toxicities of four formulation to silkworm （Bombyx mori） were evaluated in laboratory, using the leaf dipping method. The toxi symptoms of silkworms after treatment of pesticides were system atically observed. The results indicated that the LC50 s of Pyrethrins, 5% EC, lmidacloprid, 2.5% WP and Chloramine Phosphorus, 20% EC were between 0.1-10mg/L belonging to high toxicity grade; the LCs0 s of Difenoconazole and Propiconazole, 300g/L EC was 5.60×10^2mg /L, belonging to low toxicity grade. The observation of toxicosis symptoms of four formulation on silkworm displayed similar symptoms like vomitive, distorted, ＂C ＂ or ＂S ＂ shaped and repose etc.