Baseline sensitivity of natural populations and characterization of resistant strains of Botrytis cinerea to fluazinam

作者:Shao, Wenyong; Ren, Weichao; Zhang, Yu; Hou, Yiping; Duan, Yabing; Wang, Jianxin; Zhou, Mingguo; Chen, Changjun*
来源:Australasian Plant Pathology, 2015, 44(4): 375-383.
DOI:10.1007/s13313-015-0358-3

摘要

This study examined the baseline sensitivity of field populations of Botrytis cinerea before exposure to the fungicide fluazinam and evaluated the risk of fluazinam resistance. The mean EC50 (half maximal effective concentration) and minimum inhibitory concentration (MIC) for fluazinam were 0.0196 mu g/mL and < 4 mu g/mL, respectively. Five fluazinam-resistant strains were selected from wild-type isolates on potato dextrose agar (PDA) containing sub-lethal concentrations of fluazinam. The fluazinam-resistant strains were less fit than their parental isolates based on radial mycelial dry weight, pathogenicity and spore production. Moreover, on PDA amended with NaCl, the laboratory fluazinam-resistant strains grew slower than their fluazinam-sensitive parental isolates, especially at high concentrations of NaCl. Cross-resistance occurred between fluazinam and the dicarboximide procymidone and the phenylpyrrole fludioxonil.