Abstract:

In order to investigate the effects of endophytic fungus Piriformospora indica on the rhizosphere microenvironment of tobacco,a pot experiment was conducted under greenhouse conditions,using Yunyan 87 as the experimental material to analyze its effects on tobacco root exudates,rhizosphere soil enzyme activities and bacterial diversity through non-targeted metabolomics,soil enzyme activity measurement,high-throughput sequencing,and microbial community functional prediction.The results showed that the P.indica successfully colonized in the roots of tobacco,increasing the content of 18 different root exudates,mainly including acids,esters,alcohols,terpenoids,and phenolic compounds,significantly enriching the metabolism pathways of L-phenylalanine,taurine and hypotaurine,and L-tryptophan.Compared to using sterile water as a control,P.indica increased the activities of urease,sucrase,and alkaline phosphatase in tobacco rhizosphere soil,with urease and sucrase activities reaching significant levels.P.indica increased the richness and diversity of bacterial communities in tobacco rhizosphere soil,with a significant increase in Chao1 index and Observed_otus index comparing with the control.This altered the bacterial community structure at the phylum and genus levels,and increased the relative abundance of dominant phyla of Acidobacteriota and Actinobacteriaota,as well as Pseudomonas and Gemmatimonas genera.It also increased the gene abundance involved in carbohydrate metabolism and translation pathways in rhizosphere soil bacteria,which had a certain impact on bacterial community function.It indicates that P.indica could improve the rhizosphere microecological environment of tobacco,providing a theoretical basis for understanding the mechanism of their promotion of tobacco growth and tobacco planting production.

Key words: Tobacco, Pirifonospora indica, Root exudates, Soil enzyme activity, Bacterial diversity

CLC Number: 

• S572