枯梢病感病和未感病樟子松根际土壤养分及真菌群落结构季节变化

Seasonal Variation of Soil Nutrients and Fungal Community Structure in Rhizosphere of Susceptible and Non-susceptible Pinus sylvestris var.mongolica Plantations

樟子松具有抗逆性强,生长快等特点,是我国北方治沙工程的主要树种,近年来环境条件的变化导致辽宁省章古台地区樟子松人工林树势日益衰弱,樟子松枯梢病发生严重。以辽宁省章古台地区樟子松人工林枯梢病未感病樟子松(ck)和枯梢病感病樟子松(ss)为研究对象,利用高通量测序技术及qPCR技术分析不同季节感病和未感病樟子松根际土壤理化性质、真菌群落结构变化及土壤理化性质对真菌群落结构的影响。结果表明:门分类水平上Ascomycota、Basidiomycota、Mortierellomycota、Fungi-unclassified为主要的菌门,ck土样与ss土样菌群丰度具有显著差异(P<0.05),属分类水平上具有30个差异菌属,30个菌属在ck土样中的含量显著高于ss土样(P<0.05)且均为菌根真菌、深色有隔真菌、木霉菌等益生菌;冗余分析(RDA)表明,pH、OM、TN、NH_(4)^(+)、NO_(3)^(-)、AP、TP、AK、TK等环境因子是影响ck土样、ss土样春季、夏季菌群结构的主要环境因子,具有显著差异的30个菌属是影响秋季菌群结构的主要菌属。

Pinus sylvestris var.mongolica has the characteristics of strong resistance and fast growth,which plays an important role in sand control project in north China.In recent years,the changes of environmental conditions have led to the weakening of the growth of P.sylvestris var.mongolica plantation in Zhanggutai area,Liaoning province,and the serious occurrence of shoot blight disease.In this study,the physical and chemical properties of rhizosphere soil,the variation of fungal community structure and the effects of soil physical and chemical properties on fungal community structure of susceptible and non-susceptible P.sylvestris var.mongolica plantations in Zhanggutai area of Liaoning Province were analyzed by high-throughput sequencing and qPCR technology.The results showed that at phylogenetic level,Ascomycota,Basidiomycota,Mortierellomycota and Fungiunclassified were the main flora.There were significant differences in the abundance of ck soil samples and ss soil samples(P<0.05).There were 30 genera with different abundance at genus classification level.The content of 30 genera in ck soil samples was significantly higher than that in ss soil samples(P<0.05),all of which are mycorrhizal fungi,dark septal fungi,Trichoderma and other probiotics.RDA analysis showed that pH,OM,TN,NH_(4)^(+),NO_(3)^(-),AP,TP,AK and TK were the main environmental factors affecting the fungal community structure in spring and summer,and 30 genera with significant differences were the main factors affecting the microbial community structure in autumn.