Fusarium oxysporum Causes Root Rot on Gastrodia elata in Korea: Morphological, Phylogenetic, and Pathogenicity Analyses

Sang-A Lee¹ Eun-Kyung Bae¹ Chanhoon An¹ Min-Jeong Kang¹ Eung-Jun Park^2,*

¹Forest Microbiology Division, National Institute of Forest Science, Suwon 16631, Korea
²Forest Medicinal Resources Research Center, National Institute of Forest Science, Yeongju 36040, Korea

Abstract

Gastrodia elata infected with root rot disease was collected from cultivated G. elata fields in Gimcheon, Korea, in 2018. G. elata tuber surfaces exhibited root rot disease symptoms of dark-grey lesions and white fungal mycelial growth. The fungus was isolated from symptomatic tubers and cultured. Based on morphological characteristics and molecular analysis of the internal transcribed spacer region of ribosomal DNA and translation elongation factor 1-alpha, the isolated fungus was Fusarium oxysporum. This is the first report of root rot caused by F. oxysporum on G. elata tubers in Korea.

Figures & Tables

Fig. 1. Root rot caused by on tubers. (A) Symptoms of infected tubers collected from fields. (B) tubers inoculated with developed rot symptoms after 10 days. (C) A 10-day-old colony of growing on potato dextrose agar medium. (D) A 7-day-old colony of growing on potato dextrose agar medium. (E) Cross-section of the inoculated tuber in (B). (F) Cross-section of the inoculated tuber with . (G) microconidia and (H) Macroconidia. (I) Chlamydospores. Scale bar=1 cm (A-F) or 10 μm (G-I). Inoculation point was indicated with red arrow.