First Report of Chrysanthemum (Chrysanthemum morifolium) Crown Rot Caused by Fusarium solani in Korea

Abstract

In August 2010, a severe crown rot was observed on chrysanthemum (<TEX>$Chrysanthemum$</TEX> <TEX>$morifolium$</TEX> Ramat., variety Sinro) in several greenhouses located at Damyang and Muan, Jeonnam province, Korea. Three isolates (EML-CHS1, -CHS2, and -CHS3) of <TEX>$Fusarium$</TEX> were isolated from the affected plants and identified based on morphological characteristics and rDNA internal transcribed spacer (ITS) sequence analysis. Sequence analysis by BLAST indicated that EMLCHS1, -CHS2 and CHS3 were closest to a <TEX>$Fusarium$</TEX> species, <TEX>$F.$</TEX> <TEX>$solani$</TEX> with > 99% sequence similarity. Pathogenicity tests were performed on chrysanthemum with spore suspensions containing <TEX>$3.4{\times}10^6$</TEX> spores/ml using the dipping method. Ten days after inoculation, similar symptoms to those observed in the greenhouses were seen on the inoculated plants. The causal fungus was reisolated from the artificially inoculated basal stems, fulfilling Koch's postulates. To our knowledge, this is the first report of crown rot by <TEX>$Fusarium$</TEX> <TEX>$solani$</TEX> on chrysanthemum (<TEX>$Chrysanthemum$</TEX> <TEX>$morifolium$</TEX>) in Korea.