22种杀菌剂对甜瓜靶斑病菌的室内毒力测试

Toxicity of 22 fungicides against Corynespora cassiicola causing melon leaf spot

为筛选多主棒孢甜瓜分离物的高效杀菌剂,在室内采用菌丝生长速率法测定了22种杀菌剂对甜瓜多主棒孢SY和GX分离株菌丝生长的抑制能力。结果表明,50%咪鲜胺锰盐WP对多主棒孢甜瓜分离物SY和GX菌株的EC_(50)都最小,病菌对它的敏感性最高,抑菌效果最好;30%苯醚甲环唑SC、40%氟硅唑EC和80%福美双WG对多主棒孢甜瓜分离物GX分离株的EC_(50)均小于5μg·mL^(-1),抑菌效果较好,但在SY菌株上抑菌效果减弱。在试验浓度下,2个多主棒孢供试菌株对25%嘧菌酯SC、75%百菌清WP和90%多菌灵WG都非常不敏感,说明这3种杀菌剂对甜瓜靶斑病的防控不能起到有效作用。

Melon target spot(Corynespora cassiicola)is an emerging disease as a potential risk for melon production.In order to evaluate fungicides on the pathogen,indoor toxicity of 22 fungicides for Corynespora cassiicola SY strain and GX strain of melon were determined in laboratory.The results indicated that EC50 value of 50%Sporgeon WP was the most effective for both SY strain and GX strain.30%difenoconazole SC,40%flusilazole EC and 80%thiram WG also had significant inhibition activity on GX strain mycelium growth,with the EC50 values less than 5μg·mL-1,but the three fungicides were less effective on SY strain.25%azoxystrobin SC,75%chlorothalonil WP and 90%carbendazim WG were least effective on SY strain and GX strain.