Liu FeiFei, Mbenoun Michael, Barnes Irene, Roux Jolanda, Wingfield Michael J, Li GuoQing, Li JieQiong, Chen ShuaiFei
Department of Microbiology and Plant Pathology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Private Bag X20, Pretoria, 0028, South Africa.
Antonie Van Leeuwenhoek. 2015 Jun;107(6):1451-73. doi: 10.1007/s10482-015-0441-3. Epub 2015 Apr 4.
During routine surveys for possible fungal pathogens in the rapidly expanding plantations of Eucalyptus and Cunninghamia lanceolata in China, numerous isolates of unknown species in the genus Ceratocystis (Microascales) were obtained from tree wounds. In this study we identified the Ceratocystis isolates from Eucalyptus and Cunninghamia in the GuangDong, GuangXi, FuJian and HaiNan Provinces of South China based on morphology and through comparisons of DNA sequence data for the ITS, partial β-tubulin and TEF-1α gene regions. Morphological and DNA sequence comparisons revealed two previously unknown species residing in the Indo-Pacific Clade. These are described here as Ceratocystis cercfabiensis sp. nov. and Ceratocystis collisensis sp. nov. Isolates of Ceratocystis cercfabiensis showed intragenomic variation in their ITS sequences and four strains were selected for cloning of the ITS gene region. Twelve ITS haplotypes were obtained from 17 clones selected for sequencing, differing in up to seven base positions and representing two separate phylogenetic groups. This is the first evidence of multiple ITS types in isolates of Ceratocystis residing in the Indo-Pacific Clade. Caution should thus be exercised when using the ITS gene region as a barcoding marker for Ceratocystis species in this clade. This study also represents the first record of a species of Ceratocystis from Cunninghamia.
在中国快速扩张的桉树和杉木人工林中进行可能的真菌病原体常规调查期间，从树木伤口分离出许多未知种类的长喙壳属（微囊菌目）菌株。在本研究中，我们基于形态学并通过比较ITS、部分β-微管蛋白和TEF-1α基因区域的DNA序列数据，对来自中国南方广东、广西、福建和海南省的桉树上和杉木上的长喙壳属菌株进行了鉴定。形态学和DNA序列比较揭示了两个以前未知的、属于印度-太平洋分支的物种。在此将它们描述为新种Ceratocystis cercfabiensis和新种Ceratocystis collisensis。Ceratocystis cercfabiensis菌株的ITS序列显示出基因组内变异，选择了四个菌株对ITS基因区域进行克隆。从选择测序的17个克隆中获得了12个ITS单倍型，它们在多达七个碱基位置上存在差异，并代表两个独立的系统发育组。这是印度-太平洋分支中长喙壳属菌株存在多种ITS类型的首个证据。因此，在将ITS基因区域用作该分支中长喙壳属物种的条形码标记时应谨慎。本研究还代表了杉木上长喙壳属物种的首次记录。
