孙东晗 陈悦 田文学 白庆荣 赵廷昌

摘要 ：为明确吉林省西瓜蔓枯病菌Stagonosporopsis citrulli对咪鲜胺和苯醚甲环唑的抗药性水平，本试验采用菌丝生长速率法测定了151株西瓜蔓枯病菌对这两种药剂的敏感性及两种药剂对西瓜蔓枯病菌的MIC值，并测定了吉林省7个西瓜主产区的375株菌株对这两种药剂的抗性水平。结果表明，供试的151株菌株对这两种药剂的敏感性频率分布均呈连续的单峰曲线，接近正态分布;对咪鲜胺和苯醚甲环唑的敏感基线分别为（0.203 0±0.135 3）μg/mL和（0.675 9±0.394 2）μg/mL;两种药剂的最低抑制浓度MIC分别为20 μg/mL和40 μg/mL。供试375株菌株对两种杀菌剂的抗性频率均为0。本研究结果为咪鲜胺和苯醚甲环唑的合理用药策略提供了科学依据，为后续其抗性风险评估奠定了基础。

关键词 ：西瓜蔓枯病菌; 抗药性; 咪鲜胺; 苯醚甲环唑

中图分类号：

S 482.2

文献标识码： A

DOI： 10.16688/j.zwbh.2020494

Establishment of baseline sensitivity and monitoring of resistance

of Stagonosporopsis citrulli on watermelon to prochloraz

and difenoconazole in Jilin province

SUN Donghan1， CHEN Yue1， TIAN Wenxue2， BAI Qingrong1*， ZHAO Tingchang3*

（1.College of Plant Protection， Jilin Agricultural University， Changchun 130118， China; 2.Shandong

Sino-Agri United Biotechnology Co.，Ltd.， Jinan 250100， China; 3.Institute of Plant

Protection， Chinese Academy of Agricultural Sciences， Beijing 100193， China）

Abstract

To evaluate the resistance levels of Stagonosporopsis citrulli causing gummy stem blight of Citrullus lanatus in Jinlin province to prochloraz and difenoconazole， the baseline sensitivities of S.citrulli strains （n=151） to the two fungicides and the minimum inhibitory concentrations （MICs） of the two fungicides to S.citrulli strains were determined by using mycelial growth rate method.The resistance levels of 375 stains from seven main watermelon production areas of Jinlin province to two fungicides were also determined.The results showed that the sensitivity frequency distribution of tested strains（n=151） to prochloraz and difenoconazole presented continuous single peak curves， which were close to normal distribution.The baseline sensitivities of S.citrulli strains to prochloraz and difenoconazole were （0.203 0±0.135 3）μg/mL and （0.675 9±0.394 2）μg/mL， respectively.The MICs of prochloraz and difenoconazole were 20 μg/mL and 40 μg/mL， respectively.The resistance frequencies of 375 tested strains to the two fungicides were both zero.The results provided a scientific basis for rational application of prochloraz and difenoconazole， and laid a foundation for the subsequent study on the resistance risk assessment.

Key words

Stagonosporopsis citrulli; fungicide resistance; prochloraz; difenoconazole

西瓜蔓枯病主要是由Stagonosporopsis citrulli引起的世界性病害，在西瓜整个生育期均可发病，危害西瓜叶片、茎秆、藤蔓和果实[12]。在适宜的温度和湿度条件下，可迅速发展蔓延，大田种植时发病率可达20%～40%，溫室种植和连作时更可达80%，如管理不当常常会造成毁灭性的损失，严重影响西瓜的品质和产量[34]。目前关于西瓜蔓枯病的防治措施仍是以化学防治为主，咪鲜胺和苯醚甲环唑对该病害具有见效快，防治效率高等优势，备受瓜农青睐[56]。2019年对吉林省西瓜蔓枯病菌的优势种Stagonosporopsis citrulli进行了室内药剂敏感性的测定，试验结果表明病菌对咪鲜胺和苯醚甲环唑表现出了较高的敏感性。……