[Objective] The aim was to research the residue decline and final residue of acetochlor in rice.[Method] By carrying out crop field trials in 3 places including Heilongjiang,Jilin and Hunan during two years and applying GC technique,the residue decline of acetochlor in rice was analyzed and its final residue was determined.[Result] The half-life of acetochlor in rice was 4.4-8.3 d,being relatively short,and it belonged to easily degradable pesticide.Under dosage condition with effective components of 600 and 900 g/hm2,after application for one time,the determined acetochlor residues in rice were lower than 0.01 mg/kg.[Conclusion] Take multiple factors into consideration,according to the treatment with application dosage of 900 g/hm2,it was suggested that the MRL value of acetochlor in rice should be ascertained as 0.02 mg/kg temporarily and acetochlor should be applied for one time.
[目的]通过对水稻菌核秆腐病菌进行室内毒力测定与田间药效试验测定,筛选出抑菌效果较好的杀菌剂。[方法]采用生长速率法,测定12种杀菌剂和3种混剂对水稻菌核秆腐病菌的毒力作用,并进行田间药效试验。[结果]杀菌剂单剂中啶酰菌胺、丁香菌酯、醚菌酯、恶霉灵4种药剂对水稻菌核秆腐病菌的EC50值均小于0.01 mg/L,抑菌效果较好。啶酰菌胺与丁香菌酯混用质量比为5颐1时,其EC50值为0.000 12,增效系数为6.28,表明2种药剂混合后为增效作用。[结论]36%啶酰菌胺·丁香菌酯WP在200 g a.i./hm2剂量下对水稻菌核秆腐病防效最好,可作为田间防治水稻菌核秆腐病的有效药剂,为农业生产提供科学指导。
