Two New Species and a New Record of Microdochium from Grasses in Yunnan Province, South-West China

Phylogenetic analysis of Microdochium spp. associated with turfgrass and their pathogenicity in cereals

Turfgrass is frequently used today in the arrangement and aesthetic beautification of grounds in parks, gardens, median strips, recreation and sports areas. In this study, surveys were conduct in turfgrass areas in the three provinces of Türkiye. As a result of isolations from the collected samples, 44 Microdochium isolates obtained belonging to five different species including M. bolleyi, M. majus, M. nivale, M. paspali and M. sorghi which have different virulences. Identification of the isolates were performed by rDNA-ITS sequence analyzes. According to the pathogenicity tests results, the most virulent species was M. nivale M62 with a disease severity value of 91.93%. This was followed by M. bolleyi M1584 and M. majus M63, with disease severity values of 91.12% and 91.08%, respectively. The virulence of M. bolleyi isolates varied among the species. Only 13 of the 31 M. bolleyi species were found to be virulent in turfgrass, M. paspali was less virulent than the others in Poa pratensis. The most virulent isolate of each Microdochium species was tested on four different cereal varieties. M. sorghi and M. paspali had low virulence values in barley and oat than the other Microdochium species, while the other three species showed high virulence in turfgrass, wheat and barley, other than oat. In the phylogenetic neighboor-joining tree belonging to 44 Microdochium isolates clearly demonstrated that the isolates were grouped into five distinct clusters. M. nivale and M. majus were considered genetically close isolates.

Three New Species of Microdochium (Microdochiaceae, Xylariales) on Bambusaceae sp. and Saprophytic Leaves from Hainan and Yunnan, China

Species of the genus Microdochium (Microdochiaceae, Xylariales) have been reported from the whole world and separated from multiple plant hosts. The primary aim of the present study is to describe and illustrate three new species isolated from the leaf spot of Bambusaceae sp. and saprophytic leaves in Hainan and Yunnan provinces, China. The proposed three species, viz., Microdochium bambusae, M. nannuoshanense and M. phyllosaprophyticum, are based on multi-locus phylogenies from a combined dataset of ITS rDNA, LSU, RPB2 and TUB2 in conjunction with morphological characteristics. Descriptions and illustrations of three new species in the genus are provided.