Genetic Diversity, Pathogenicity, and Fungicide Response of Fusarium oxysporum f. sp. fragariae Isolated from Strawberry Plants in Korea

Abstract

Fusarium wilt caused by Fusarium oxysporum f. sp. fragariae (Fof) is the most important diseases of a strawberry field in Korea. We surveyed phylogenetic analysis, pathogenicity test, and fungicide response about Fof isolates isolated from Korea. Twenty-seven isolates of F. oxysporum isolated from strawberry plants were conducted in this study. Specific amplification by Fof specific primer was confirmed in all 26 isolates except Fo080701 isolate. The nuclear ribosomal intergenic spacer region and the translation elongation factor EFlα gene sequences of isolates revealed three main lineages. Most of all isolates were contained DNA lineage group 1, but 2 and 3 group was shown only one and three isolates, respectively. All isolates were shown in pathogenicity with cv. Seolhyang. The EC50 mean values of prochloraz ranged 0.02–0.1 μg/ml except for Fo080701 and effectively inhibited mycelial growth at low concentrations. The EC50 value of metconazole was also 0.04–0.22 μg/ml, showing a similar inhibitory effect to that of prochloraz. The EC50 value of pyraclostrobin was 0.23–168.01 μg/ml, which was different according to the strain. In the field trial, boscalid+fludioxonil, fluxapyroxad+pyraclostrobin, and prochloraz manganese were selected as the effective fungicides for controlling Fusarium wilt.

Keywords

• fusarium wilt
• phylogenetic analysis
• prochloraz