Pandey Madan, Haskell Clayton L, Cowell Juliette D, Amiri Achour
Department of Plant Pathology, Tree Fruit Research and Extension Center, Washington State University, 1100 N. Western Ave., Wenatchee, WA 98801, USA.
Department of Horticulture, University of Minnesota, 1790 Folwell Ave., St. Paul, MN 55108, USA.
J Fungi (Basel). 2025 Jan 15;11(1):61. doi: 10.3390/jof11010061.
Difenoconazole (DIF), a demethylation inhibitor fungicide, was registered in 2016 for the control of postharvest diseases of pome fruits. In this study, 162 isolates from ( = 31) and 13 other "non-" spp., i.e., ( = 52), ( = 32), ( = 15), ( = 9), ( = 8), ( = 5), ( = 3), ( = 2), along with one isolate each of , , , , and , were collected from multiple packinghouses in the U.S. Pacific Northwest. In vitro sensitivity assays showed similar sensitivities of spores and mycelia across species with the mean EC values ranging from 0.01 for ( = 8) to 1.33 μg mL for ( = 2), whereas the mean EC were 0.03, 0.12, 0.19, and 0.51 μg mL for ( = 31), ( = 9), ( = 52), and ( = 5), respectively. The recommended rate of DIF controlled and isolates but not all isolates of four other spp. on Fuji apples after five months at 1.5 °C. The mixture of DIF + fludioxonil (FDL) (Academy) controlled all the dual-sensitive isolates (DIFFDL) and DIF single-resistant (DIF) isolates among the six species tested but not the FDL and dual DIFFDL isolates. Notable polymorphism was detected in the gene of the "non-" species with four mutations located at four residues. Although the isolates analyzed in this study had not previously been exposed to DIF, the findings indicate variable sensitivity levels among the spp.
苯醚甲环唑（DIF）是一种脱甲基抑制剂类杀菌剂，于2016年登记用于控制梨果采后病害。在本研究中，从美国太平洋西北地区的多个包装厂收集了来自31个苹果链核盘菌菌株以及其他13个“非”苹果链核盘菌属物种的162个分离株，即李链核盘菌（52个）、核果链核盘菌（32个）、扩展链核盘菌（15个）、果生链核盘菌（9个）、葡萄链核盘菌（8个）、银叶链核盘菌（5个）、小穴链核盘菌（3个）、嗜果链核盘菌（2个），以及苹果黑腐皮壳菌、苹果壳囊孢菌、苹果炭疽病菌、苹果盘二孢菌和苹果间座壳菌各1个分离株。体外敏感性测定表明，不同物种的孢子和菌丝体敏感性相似，平均EC50值范围为嗜果链核盘菌（8个）的0.01 μg/mL至小穴链核盘菌（2个）的1.33 μg/mL，而苹果链核盘菌（31个）、果生链核盘菌（9个）、李链核盘菌（52个）和核果链核盘菌（5个）的平均EC50分别为0.03、0.12、0.19和0.51 μg/mL。在1.5℃下存放五个月后，推荐剂量的苯醚甲环唑能控制苹果链核盘菌和李链核盘菌分离株，但不能控制其他四种链核盘菌属物种的所有分离株。苯醚甲环唑+咯菌腈（FDL）（商品名Academy）的混合物能控制所测试的六个物种中的所有双敏感分离株（DIFFDL）和苯醚甲环唑单抗性（DIFR）分离株，但不能控制咯菌腈单抗性（FDLR）和双抗性（DIFFDLR）分离株。在“非”苹果链核盘菌属物种的Sdh2基因中检测到显著的多态性，在四个残基处有四个突变。尽管本研究中分析的分离株以前未接触过苯醚甲环唑，但研究结果表明链核盘菌属物种之间的敏感性水平存在差异。
