Dipartimento di Protezione delle Piante-Centro per la Conservazione e la Valorizzazione della Biodiversità Vegetale and Unità di Ricerca Istituto Nazionale di Biostrutture e Biosistemi, Università degli Studi di Sassari, Italy.
Mycologia. 2010 Jul-Aug;102(4):803-12. doi: 10.3852/09-201.
The Mediterranean island of Sardinia is well known for high levels of vascular plant diversity and endemism, but little is known about its microbial diversity. Under the hypothesis that Fusarium species would show similarly high diversity, we estimated variability in Fusarium species composition among 10 sites around the island. Markers previously adopted for multilocus sequence typing (MLST) were used to determine multilocus DNA sequence haplotypes for 263 Fusarium isolates. In addition portions of the translation elongation factor 1-alpha and second largest RNA polymerase subunit genes were sequenced for all isolates. The intergenic spacer (IGS) region of the nuclear ribosomal RNA gene repeat was sequenced for members of the F. oxysporum species complex (FOSC), and a portion of the nuclear ribosomal RNA gene repeat comprising the internal transcribed spacer (ITS) and part of the large nuclear ribosomal RNA subunit was sequenced for members of the F. solani species complex (FSSC). Seventy-three multilocus haplotypes were identified among the 263 isolates typed, of which 48 represented FOSC and FSSC. Thirty-seven of 48 FOSC two-locus and FSSC three-locus haplotypes had not been observed previously. The 38 non-FOSC/FSSC fusaria comprised 25 haplotypes distributed among 10 species, five of which appear to represent novel, phylogenetically distinct species. In general newly discovered haplotypes were restricted to one or a few sites. All FSSC isolates represented new haplotypes in phylogenetic species FSSC 5 and 9, which differ from the phylogenetic species dominant in soils worldwide. No obvious correlations were found between haplotype diversity and geospatial or habitat distribution. Overall these results indicate a high degree of Fusarium genetic diversity on multiple geographic scales within Sardinia. These results contrast with recent work showing that common, cosmopolitan species dominate Sardinia's Trichoderma biodiversity. All data are available for access and viewing from the FUSARIUM-ID database.
撒丁岛是地中海的一个岛屿，以其丰富的维管植物多样性和特有性而闻名，但人们对其微生物多样性知之甚少。根据镰刀菌物种也具有高度多样性的假设，我们估计了该岛周围 10 个地点的镰刀菌物种组成的变异性。先前用于多位点序列分型（MLST）的标记用于确定 263 个镰刀菌分离物的多位点 DNA 序列单倍型。此外，所有分离物的翻译延伸因子 1-α和第二大亚基 RNA 聚合酶基因的部分序列被测序。核核糖体 RNA 基因重复的基因间 spacer（IGS）区域被测序用于 F. oxysporum 种复合体（FOSC）的成员，核核糖体 RNA 基因重复的一部分包括内部转录间隔区（ITS）和大亚基核核糖体 RNA 的一部分被测序用于 F. solani 种复合体（FSSC）的成员。在分型的 263 个分离物中，鉴定出 73 个多位点单倍型，其中 48 个代表 FOSC 和 FSSC。48 个 FOSC 二位点和 FSSC 三位点单倍型中有 37 个以前未观察到。38 个非 FOSC/FSSC 镰刀菌包含 10 个种中的 25 个单倍型，其中 5 个似乎代表新的、系统发育上不同的种。一般来说，新发现的单倍型局限于一个或几个地点。FSSC 所有分离物代表 FSSC 5 和 9 中新型单倍型，它们与在世界各地土壤中占主导地位的系统发育种不同。在地理空间或生境分布方面没有发现明显的相关性。总的来说，这些结果表明在撒丁岛的多个地理尺度上存在高度的镰刀菌遗传多样性。这些结果与最近的研究结果形成对比，最近的研究结果表明，常见的世界性物种主导着撒丁岛的 Trichoderma 生物多样性。所有数据均可从 FUSARIUM-ID 数据库中访问和查看。
