4种杀菌剂对瓜果腐霉病菌的室内毒力及田间防效测定

采用菌丝生长速率法测定了乙酸铜、噁霉灵、霜霉威、代森锰锌4种杀菌剂对瓜果腐霉病菌(Pythiumaphanidermatum)的毒力,各药剂的EC50值依次为:30.292 3、5.891 7、34.331 9、65.982 6μg/mL。可见噁霉灵30%水剂对瓜果腐霉病菌表现出较强的毒力。对4种杀菌剂还进行了田间黄瓜猝倒病的防治试验,其防效依次为83.65%、80.14%、80.91%、42.48%。根据室内毒力测定和田间药效试验结果,乙酸铜20%可湿性粉剂、噁霉灵30%水剂、霜霉威盐酸盐722克/升水剂对黄瓜猝倒病均具有较高的防效。

The Toxicity Tests and Field Control Effects of Four Fungicides Against Pythiumaphanidermatum

The laboratory toxicities of copper acetate,hymexazol,propamocarb and mancozeb against Pythiumaphanidermatum were tested by using mycelial growth rate method,and the EC50 values of these fungicides were 30.292 3,5.891 7,34.331 9μg/mL and 65.982 6μg/mL, respectively.The results showed that hymexazol had stronger toxicity to the Pythiumap hanidermatum.Field trials of the four fungicides against seedling damping-off of cueumber were also conducted.At the highest recommended use concentration of each fungicide,their control effects were 83.65%,80.14%,80.91% and 42.48% in turn,respectively.Based on the results of toxicity tests and field trials,copper acetate 35% WP,hymexazol 30% AS and propamocarb 72.2% AS could be recommende for controlling seedling damping-off of cueumber.