Fan F, Hamada M S, Li N, Li G Q, Luo C X
Key Lab of Horticultural Plant Biology, Ministry of Education, and College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
College of Plant Science and Technology, Huazhong Agricultural University, and Pesticides Department, Faculty of Agriculture, Mansoura University, Mansoura 35516, Egypt.
Plant Dis. 2017 Apr;101(4):601-606. doi: 10.1094/PDIS-09-16-1227-RE. Epub 2017 Feb 3.
Two hundred and forty isolates of Botrytis cinerea were collected during the early summer of 2012 and 2013 from strawberry greenhouses in 10 locations in Hubei Province and examined for sensitivity to five fungicides, most of which were commonly used to control this fungus. High frequency of resistance to carbendazim (Car, 63.63%) and cyprodinil (Cyp, 42.42%) was detected. Boscalid-resistant (Bos) isolates were detected for the first time in China, whereas no fludioxonil-resistant isolates were identified. Dual resistance to carbendazim and diethofencarb (Die) was also detected. There were six phenotypes of resistance profile (i.e., CarDieBosCyp, CarDieBosCyp, CarDieBosCyp, CarDieBosCyp, CarDieBosCyp, and CarDieBosCyp). CarDieBosCyp and CarDieBosCyp were the most common phenotypes, occurring at eight and seven locations, respectively. After 10 successive transfers on fungicide-free potato dextrose agar, tested resistant isolates retained levels of resistance similar to or comparative with the initial generation, indicating the stability of these resistances. Fitness evaluations based on investigation of mycelial growth, osmotic sensitivity, sporulation in vitro and in vivo, and virulence revealed the uncompromising fitness in resistant isolates, except that decreased virulence was observed in Bos isolates. The molecular basis of carbendazim, diethofencarb, and boscalid resistance was investigated. Results showed that all 13 sequenced carbendazim-resistant isolates harbored the mutation E198V or E198A in the β-tubulin gene and the five isolates with dual resistance to carbendazim and diethofencarb showed the mutation E198K in the same gene. Bos isolates possessed the H272R mutation in succinate dehydrogenase subunit B gene. The results achieved in this study challenge the current management strategies for B. cinerea, which largely depend on applications of these fungicides.
2012年和2013年初夏，从湖北省10个地点的草莓温室中收集了240株灰葡萄孢分离株，并检测了它们对五种杀菌剂的敏感性，其中大部分杀菌剂常用于防治这种真菌。检测到对多菌灵（Car，63.63%）和嘧菌环胺（Cyp，42.42%）的高抗性频率。在中国首次检测到对啶酰菌胺（Bos）有抗性的分离株，而未鉴定出对咯菌腈有抗性的分离株。还检测到对多菌灵和乙霉威（Die）的双重抗性。有六种抗性谱表型（即CarDieBosCyp、CarDieBosCyp、CarDieBosCyp、CarDieBosCyp、CarDieBosCyp和CarDieBosCyp）。CarDieBosCyp和CarDieBosCyp是最常见的表型，分别出现在八个和七个地点。在不含杀菌剂的马铃薯葡萄糖琼脂上连续转接10代后，测试的抗性分离株保持了与初代相似或相当的抗性水平，表明这些抗性具有稳定性。基于菌丝生长、渗透敏感性、体外和体内产孢以及毒力的适应性评估显示，抗性分离株具有不受影响的适应性，除了在Bos分离株中观察到毒力下降。研究了多菌灵、乙霉威和啶酰菌胺抗性的分子基础。结果表明所有1３株测序的多菌灵抗性分离株在β-微管蛋白基因中都存在E198V或E198A突变，五株对多菌灵和乙霉威具有双重抗性的分离株在同一基因中显示出E198K突变。Bos分离株在琥珀酸脱氢酶亚基B基因中具有H272R突变。本研究取得的结果对目前主要依赖这些杀菌剂应用的灰葡萄孢管理策略提出了挑战。
