贵州煤矸石山香根草根系及根际土丛枝菌根真菌(AMF)群落的季节动态研究

以煤矸石山种植年限为17年的香根草Vetiveria zizanioides为研究对象,采用高通量测序技术研究香根草根系及根际土丛枝菌根真菌(arbuscular mycorrhizal fungi,AMF)群落的季节动态.并利用Spearman、NMDS、RDA和Mantel-test等统计学方法分析了 AMF孢子密...

Seasonal dynamic changes of community of arbuscular mycorrhizal fungi(AMF)in root system and rhizosphere soil of Vetiveria zizanioides in coal gangue in Guizhou of Southwest China

The high-throughput sequencing was used to determine the seasonal dynamics of community of arbuscular mycorrhizal fungi(AMF)in the root and rhizosphere soil of Vetiveria zizanioides in coal gangue dump with planting period of 17 years.Spearman,NMDS,RDA and Mantel test were used to analyze the correlation among AMF spore density,colonization rate,physicochemical properties of soil,richness and diversity index.The results showed that the spore density and colonization rate of AMF in summer were significantly higher than those in spring and autumn.In spring,summer and autumn,127 OTUs,258 OTUs and 96 OTUs were obtained from root system,rhizosphere soil and both of them,respectively,and 7 genera and 4 families of AMF were identified.Glomus was the dominant genus in the coal gangue dump.The AMF diversity and richness index of root first decreased and then increased with the seasonal change;the AMF diversity index of rhizosphere soil first decreased and then increased,while the richness index showed a decreasing trend with the seasonal change.Shannon,Chao1 and ACE indexes of rhizosphere soil in spring were significantly higher than those of root system,and the Chaol index of rhizosphere soil was significantly higher than that of root in summer.NMDS analysis showed that the distribution of AMF community in summer was significantly different from that in other seasons.Spearman analysis showed that total potassium content in roots was significantly positively correlated with diversity and richness index of AMF.There was a significant negative correlation between available phosphorus and AMF richness index.The results of RDA analysis showed that AMF community composition was positively correlated with total phosphorus,total nitrogen,total potassium and available phosphorus in root system in spring and summer and in rhizosphere soil in summer and autumn,but it was negatively correlated with organic matter.Mantel test analysis showed that pH,organic matter,total nitrogen,total potassium,available phosphorus and sampling season significantly affected mycorrhizal colonization rate,and organic matter and total nitrogen were the dominant factors affecting spore density.