Diversity of aquatic fungi in different areas of Lake Taihu

Abstract

采用聚合酶链式反应-变性梯度凝胶电泳(PCR-DGGE)的方法,研究太湖不同湖区水体及沉积物中的水生真菌多样性及环境因子对其的影响.结果表明,2009年5月份太湖水生真菌群落具有较为丰富的多样性组成.东半湖水生真菌多样性指数较西半湖高,湖心区最低.不同湖区水生真菌群落的遗传结构和主要类群组成存在空间差异,东半湖真菌类群较多,湖心区最少.系统发育分析显示太湖水生真菌优势类群主要归属于真菌界的子囊菌门(Ascomycota)和担子菌门(Basidiomycota),包含8个目,分别占所有序列的57.7%和26.9%,它们在不同湖区均有分布.经检测发现卵菌纲(Oo-mycetes)水霉目(Saprolegniales)一种,仅存在于东太湖水体中;沉积物中的特有真菌类群主要归属于壶菌门(Chytridiomy-cota)和接合菌门(Zygomycota).这些具有空间分布差异的类群约占所有序列的15.4%.聚类及典型相关分析表明,太湖不同湖区水生真菌多样性存在差异,这与湖区间不同的营养水平、风浪扰动状况等因素有关.;Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis (PCR-DGGE) was applied to analyze the diversity of aquatic fungi in the water and sediment of Lake Taihu. The results indicated that the diversity of aquatic fungi community in Lake Taihu is highest on May, 2009. The fungi diversity indexes in the west region of the lake were lower than those in the east region, and the fungi diversity indexes in the center region of the lake were the lowest. Aquatic fungal genetic structure and community composition of major groups had spatial difference in different areas of Lake Taihu. The fungal groups in the east of lake were more than those in the west, and the groups in the center of lake were the least. Phylogenetic analyses mainly placed the majority of the aquatic fungi in Lake Taihu within two fungal phyla, Ascomycota and Basidiomycota, which contained 8 fungal orders, accounted for 57.7% and 26.9% of the sequences, respectively. The fungi, which were only found in the water of East Lake Taihu f belonged to Saprolegniales of Oomycetes and those, which were only found in the sediment, belonged to Chytridiomycota and Zygo-mycota. These groups, which had differences in the vertical distribution, accounted for 15.4% of the sequences. Cluster analysis and Canonical Correlation analysis showed that fungal diversity had spatial differences in Lake Taihu. The differences were related to different nutrient levels 4 wave distuitances and other factors.