Fusarium amaranthuense sp. nov. from amaranth is an emergent species closely related to Fusarium circinatum

Abstract Background Amaranth (Amaranthus spp. L) is not native in South Korea but cultivated in small scales for ornamental purpose as well as a leafy vegetables and pseudo cereals. In this study, a new species within the genus Fusarium was isolated from amaranth showing stem rot symptom from a farmer field in Hwaseong, South Korea. The diseased characterized by dark-brown spot with black border and then get withered.Methods and results Phylogenetic analysis based concatenated sequences of translation elongation factor 1-alpha and DNA-dependent RNA polymerase II second largest subunit genes, revealed that the obtained isolate was clearly distinct other species of Fusarium fujikuroi species complex and the closely related to F. circinatum. Cultural and morphological characteristics and pathogenicity on healthy amaranth plant (stem and leaves) were examined. The isolate was readily differentiating from F. circinatum based on 1–5 septate macro conidia and absence of sterile hyphae.Conclusions Based on molecular and morphological characteristics, this fungus demonstrated to be a new species and described here as Fusarium amaranthuense, the causal agent of stem rot of amaranth in South Korea.