Taxonomy Of Orbiliaceous Fungi From Four Provinces Regions In Southern China

The Orbiliaceae is the monotype family of Orbiliales Orbiliomycetes, which is characterized by light-colored, waxy, translucent and small apothecia. The anamorphic states of Orbiliaceae detected so far belong in about twelve genera of hyphomycetes in which nematode-trapping fungi were included. So far, the world monograph of the group have not been published.The survey of Orbiliaceous fungi from Guangdong, Guangxi, Hainan and Guizhou have been conducted and more than200specimens were collected. The anamorphs were isolated from the ascospores of Orbiliaceous fungi. The results are as follows:1. Based on morphological taxonomy of the collected specimens,8species of Hyalorbilia and28species of Orbilia have been identified. Among them, Orbilia biguttulata, Orbilia chongzuoensis and Orbilia cengongensis as new species; H. japonica, H. tortuosa, O. flexispora, O. comma, O. fabacearum, O. ovoidea, O. pisciformis, O. corculispora, O. phragmotricha, O. pilifera, O. aurantiorubra, O. epipora, O. xanthoguttulata, O. eucalypti were reported for the first time from China, H. arcuata was reported for the first time from Chinese Mainland, and three Orbilia were not identified. The research offered significant supplement of systematic taxonomy to the Orbiliaceous fungi.2. Nine teleomorph-anamorph connections of the Orbilia have been found, among which including a pair of connection between nematode-trapping fungi and its teleomorph. The research provided more valuable materials to molecular phylogenetics.3. Based on Orbiliaceous fungi teleomorph-anamorph connection, the anamorphs were isolated from the ascospores of Orbilia and they were studied to control Plant disease. The result was O. orientalis anamorph has induced constricting rings to catch nematode, O. aurantiorubra anamorph extract has inhibition on Ralstonia solanacearum.4. Phylogenetic trees were made using all Orbilia anamorphs ITS and partial28S sequence and related species ITS and partial28S sequence from GenBank, among which including40ITS sequences and34partial28S sequences. It showed that the capture nematodes species formed different monophyletic clades according to different capturing device. The species with globose and elliptical ascospores produce Dicranidion anamorph formed a clade. The species produce Trinacrium anamorph formed a clade, having Y-shape conidium and T-shape conidium. The species produce Dactylella anamorph into different clades on Phylogenetic Trees, the concept of the genus is heterogeneous.