HomePlant DiseaseVol. 100, No. 8First Report of Lotus Root Disease Caused by Fusarium tricinctum in China PreviousNext DISEASE NOTES OPENOpen Access licenseFirst Report of Lotus Root Disease Caused by Fusarium tricinctum in ChinaJ. Li, H. Li, L. Zheng, S. L. Yan, and Q. Z. WangJ. LiSearch for more papers by this author, H. LiSearch for more papers by this author, L. ZhengSearch for more papers by this author, S. L. YanSearch for more papers by this author, and Q. Z. WangSearch for more papers by this authorAffiliationsAuthors and Affiliations J. Li H. Li , College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China L. Zheng , Key Lab of Plant Pathology of Hubei Province, Huazhong Agricultural University, Wuhan 430070, China S. L. Yan Q. Z. Wang , College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China Published Online:20 May 2016https://doi.org/10.1094/PDIS-04-15-0473-PDNAboutSections ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InRedditEmailWechat Lotus root is a fresh market vegetable of high economic value in southern regions of the Yangtze River in China. In 2010, postharvest root rot was observed on lotus in Zhushan, Hubei Province. Symptoms ranged from small lesions that were black spots, up to internal browning, which led to economic loss. Disease symptoms occurred mainly in the stems and roots, with browning to dark-browning of exterior surface, and additionally a progressive decay area. Finally, lotus roots wilted and died. Small pieces of infected tissue were surface-disinfested with 70% ethanol for 2 min and then 3% sodium hypochlorite for 5 min. After 5 days of incubation on potato dextrose agar (PDA) at 25°C in the dark, a fungus was consistently recovered from diseased tissues and identified as Fusarium sp. On PDA, cultures grew rapidly and formed abundant dense mycelia that were initially white, but became pink, red, or purple after 8 days. On carnation leaf agar (CLA), macroconidia were short to medium in length, 3 to 5 septate, distinctly curved to lunate, and relatively slender with a curved tapering apical cell and an obviously foot-shaped basal cell. The macroconidia appeared to be pointed at both ends. Microconidia were abundant and oval, napiform, or pyriform in shape, and clustered in false heads. The pathogen was identified as Fusarium tricinctum based on previous descriptions (Leslie and Summerell 2006; Nelson et al. 1983). The ITS region comprising ITS1, ITS2, and 5.8S rDNA was amplified using primers ITS-1 and ITS-4. BLAST analysis of the sequence showed 100% similarity in the overlapping 517 bp portion with F. tricinctum sequence in GenBank (Accession No. GQ922562.1). A pathogenicity test was performed in the laboratory on 10 lotus roots with isolate LR-1. A 2-ml conidial suspension (1 × 105 conidia/ml) of the isolate was injected into each lotus root and an equal amount of sterile distilled water treated as a control. All treated lotus roots were placed in an incubator and maintained at 25°C and 78 ± 2% relative humidity. Typical symptoms of dark brown surface discoloration and rhizome rot were observed on the surface of all inoculated lotus roots after inoculation of 15 days and no symptoms were found on the water control. Koch’s postulates were fulfilled by reisolation of F. tricinctum from diseased rots. There is only species of F. oxysporum known to be associated with lotus root disease (Zhou et al. 2004). To our knowledge, this is the first report of F. tricinctum infecting postharvest lotus roots in China, and this pathogen and related disease symptoms must be taken into consideration to prolong the storage of postharvest lotus roots.