几种杀菌剂对茶轮斑病菌的室内毒力及田间药效

摘要

The sensitivity of P .theae against seven fungicides was determined by colony diameter method and then the selected fungicides with high sensitivity against P .theae were tested in field to study the control efficiency for screening the optimum chemical agents against Pestalotiopsis theae.The results showed that EC50 of Azoxystrobin,Score,Propiconazole,Chlorothalonil and Benomyl with high sensitivity against P .theae is 0.0947~3.0630μg/mL but EC50 of Thiophanate methyl and Carbendazim with medium sensitivity against P .theae is 6.964 9 μg/mL and 7.040 5 μg/mL respectively.The field control efficiency of 25% Azoxystrobin SC (150 g/hm2 ),10% Score WC (125 g/ hm2 ),25%Propiconazole EC (112.5 g/hm2 ),75% Chlorothalonil WP and 50% Benomyl WP (325 g/ hm2 )is 86.96%,81.16%,74.79%,72. 38% and 62.21% separately.%为了筛选防治茶轮斑病的化学药剂，采用菌落直径法测定了茶轮斑病菌对7种杀菌剂的敏感性，并对茶轮斑病菌高度敏感药剂进行田间药效试验。结果表明：轮斑病菌对阿米西达、世高、丙环唑、百菌清和苯菌灵高度敏感，其抑制中浓度（EC50）在0．0947～3．0630μg/mL；甲基托布津和多菌灵的 EC50分别为6．9649μg/mL 和7．0405μg/mL，表现为中度敏感（EC50＝5～20μg/mL）；田间药效以25％阿米西达SC 150 g/hm2的防效最高，达86．96％；其次为10％世高 WG 125 g/hm2、25％丙环唑 EC 112．5 g/hm2和75％百菌清WP 125 g/hm2，防效分别为81．16％、74．79％和72．38％；50％苯菌灵WP 325 g/hm2防效最低，为62．21％。