典型稻田土壤真菌群落结构及多样性对比

为了解中国主要稻作区内不同母质发育的稻田土壤真菌群落结构和多样性差异，本研究选取由砖红壤、红壤、盐碱土、黑土和紫色土发育而来的5种中国典型稻田土壤为研究对象，利用高通量测序技术对土壤真菌群落组成及多样性进行对比分析.结果表明：5种典型稻田土壤的含水量、pH值、盐度及容重差异显著（P<0.05）；从Chao1指数来看，稻田土壤真菌群落丰度红壤型 > 黑土型 > 砖红壤型 > 紫色土型 > 盐碱土型.从ACE指数来看，群落丰度黑土型 > 红壤型 > 砖红壤型 > 紫色土型 > 盐碱土型.Shannon指数和Simpson指数均表现为群落多样性黑土型 > 紫色土型 > 红壤型 > 砖红壤型 > 盐碱土型；5种典型稻田土壤真菌门水平相对丰度最高的均是子囊菌门（Ascomycota）；砖红壤型和红壤型稻田土壤的优势真菌属为翅孢壳属（Emericellopsis），紫色土型稻田土壤的优势真菌属为翅孢壳属、枝鼻菌属（Cladorrhinum）和柄孢壳属（Zopfiella），黑土型稻田土壤的优势真菌属为翅孢壳属和明梭孢属（Monographella），盐碱土型稻田土壤的优势真菌属为瓶头霉属（Phialocephala）；石黄衣属（Xanthoria）、Cyberlindnera、青霉菌属（Penicillium）和Westerdykella的相对丰度与土壤pH值呈显著负相关（P<0.05），Ceroophora的相对丰度与土壤含水量呈极显著负相关（P<0.01）；帚枝霉属（Sarocladium）的相对丰度与可溶性有机碳呈极显著正相关（P<0.01）.以上研究表明，稻田真菌的群落结构和多样性受稻田开垦前土壤类型的影响，真菌物种丰度和优势菌种类型对土壤理化性质变化的响应较为敏感.

Comparison of fungal community structure and diversity in typical paddy fields

To understand the differences in fungal community structure and diversity in paddy field soils developed from different parent materials in the main rice growing areas of China, five typical paddy soils, i.e., latosol, red soil, saline alkali soil, black soil and purple soil, were analyzed for the fungi species composition and community diversity by high-throughput sequencing technology. Soil water content, pH, salinity, and bulk density were significantly different (P<0.05) beween the five typical paddy soils. Chao1index indicated that the richness of the fungal community in the paddy soil types was in the order of red soil > black soil > latosol > purple soil > saline-alkali soil. The ACE index suggested that the richness of the fungal communities was in the order of black soil > red soil > latosol > purple soil > saline-alkali soil. Both Shannon index and Simpson index of community diversity were in the order of black soil > purple soil > red soil > latosol > saline-alkali soil. The phylum with the highest relative abundance was Ascomycota in all five typical paddy soils. The dominant fungi genera were Emericellopsis, (Emericellopsis, Cladorrhinum and Zopfiella), (Emericellopsis and Monographella), and Phialocephala for the paddy soils developed from latosol and red soil, purple soil, black soil and saline alkali soil, respectively. The relative abundance of Xanthoria, Cyberlindnera, Penicillium, and Westerdykella were significantly and negatively correlated with soil pH (P<0.05). Furthermore, the relative abundance of Ceroophora was significantly and negatively correlated with soil water content, and the relative abundance of Sarocladium was significantly and positively with dissolved organic carbon (P<0.01) across soil types. The fungi community structure and diversity were significantly affected by the paddy soil developed from previous reclamation types, and the fungi genera richness and dominant genera were sensitive to the changes of soil physical and chemical properties.