应用PCR-DGGE分析三江湿地土壤真菌群落结构的多样性

Diversity Analysis of Soil Fungal Community Structure in Sanjiang Wetland by PCR-DGGE

采用PCR-DGGE技术,研究毛苔草湿地土壤、小叶章湿地土壤(氮肥施用量分别为0、20、40和60 kg/hm2)和岛状林湿地土壤在生长期(2010年7月和2011年6月)和凋落期(2010年10月)的真菌群落结构变化规律.结果表明:湿地植物生长期和凋落期真菌群落结构差异显著;退化程度较高的岛状林湿地土壤真菌群落的多样性指数最高,2010年7月、10月和2011年6月多样性指数分别为3.22、3.25和3.21;在小叶章湿地土壤中添加氮肥20～40 kg/hm2,2010年7月、10月和2011年6月湿地土壤真菌群落的多样性指数分别升至0.27、0.15和0.05.对湿地土壤真菌18S rDNA基因测序分析可知,三江湿地土壤真菌类群主要包括外囊菌纲(Taphrinomycetes)、座囊菌纲(Dothideomycetes)和锤舌菌纲(Leotiomycetes),其中锤舌菌纲是该湿地主要的土壤真菌类群.

Variation of the fungal community structure in Carex lasiocarpa wetlands soil, Calamagrostis angustifolia wetlands soil with nitrogen fertilizer application of 0, 20, 40, 60 kg/hm2 and island forest wetlands soil from Sanjiang Wetland were investigated by PCR- DGGE during the growing season （July 2010 and June 2011 ） and litter season （October 2010）. The results indicated that there was a significant difference between the fungal community structures in the growing season and in the litter season. Island forest wetlands soil which was seriously degraded showed the highest diversity index of fungal community （3.22, 3.25 and 3.21 respectively）. Application of 20-40 kg/hm2 nitrogen fertilizer in the Calamagrostis angustifolia wetlands soil increased the diversity index of the fungi to 0.27, 0. 15 and 0.05. Based on sequencing of the fungal 18S rDNA fragments, the main fungal populations in the Sanjiang Wetland were Dothideomycetes, Taphrinomycetes and Leotiomycetes, among which Leotiomycetes was dominant.