2017年—2021年江苏省小麦赤霉病菌群体对4种杀菌剂的抗药性监测

Resistance of Fusarium asiaticum to four fungicides in Jiangsu province from 2017 to 2021

为明确江苏省小麦赤霉病菌群体对常用杀菌剂的抗药性情况,本研究于2017年-2021年连续5年分别从苏南、苏北及苏中小麦种植区采集病穗,分离培养获得赤霉病菌菌株共计4 055株,采用区分剂量法测定了供试菌株对4种杀菌剂(多菌灵、氰烯菌酯、戊唑醇和咪鲜胺)的抗性频率。结果表明:2017年-2021年江苏省田间小麦赤霉病菌对多菌灵的抗性频率分别为58.44%、56.30%、44.68%、48.28%、46.39%,呈逐年下降的趋势;不同地区小麦赤霉病菌对多菌灵的抗药性呈现地区差异性,苏北地区对多菌灵的抗性频率最高,其次是苏中地区,抗性频率最低的是苏南地区。2021年首次在田间采集到对氰烯菌酯、戊唑醇和咪鲜胺的抗性菌株,其抗性频率分别为0.45%、0.89%和0.09%,在以上的抗性菌株中同时具有多菌灵抗性的双重抗性菌株。表明江苏省小麦赤霉病菌对氰烯菌酯、戊唑醇和咪鲜胺产生了抗药性,虽抗性频率较低,仍需尽快制定田间抗性治理方案,延缓田间病菌对常用杀菌剂的抗性发展。

This study aimed to clarify the resistance of Fusarium asiaticum to commonly used fungicides in Jiangsu province. Diseased ears were collected from wheat planting areas in southern, northern and central Jiangsu for five consecutive years from 2017 to 2021, and a total of 4 055 field scab strains were isolated. The resistance frequency of wheat scab strains to carbendazim, phenamacril, tebuconazole and prochloraz in different years was determined by differential measurement. The results showed that from 2017 to 2021, the resistance frequency of wheat scab strains to carbendazim in Jiangsu province was 58.44%, 56.30%, 44.68%, 48.28% and 46.39%, respectively, showing a downward trend year by year. The resistance of wheat scab to carbendazim in different regions of Jiangsu province also showed regional differences. The resistance frequency to carbendazim was the highest in northern Jiangsu, followed by central Jiangsu, and the lowest in southern Jiangsu. In 2021, the resistant strains of phenamacril, tebuconazole and prochloraz were collected in the field for the first time, and their resistance frequency was 0.45%, 0.89% and 0.09%, respectively. At the same time, it was found that the above-mentioned resistant strains were also resistant to carbendazim, indicating they were double-resistant strains. The above results showed that wheat scab in Jiangsu province has developed resistance to phenamacril, tebuconazole and prochloraz. Although the resistance frequency was low, it was still necessary to formulate a field resistance management plan as soon as possible to delay the development of resistance to commonly used fungicides in the field.