Study On Differences In Rhizosphere Microbial Community Structure Of Different Soil Types Cabernet Sauvignon Grapes In Helan Mountain,Ningxia

The eastern foothills of Helan Mountain in Ningxia are recognized as one of the most suitable areas for wine viticulture in the world,with abundant resources,obvious differences in regional soil types,and great influence of soil on grape rhizosphere microbial population.In order to analyze the similarity and differences between the physicochemical properties and microbial population structure of Cabernet Sauvignon rhizosphere and non-rhizosphere soil under different soil types,the dominant flora was screened.In this study,the physicochemical indexes,soil trace elements and soil enzyme activities of rhizosphere and non-rhizosphere soils in the cultivation area of Cabernet Sauvignon in three different soil types in the eastern foothills of Helan Mountain were determined,and the diversity and composition of vineyard soil bacteria and fungi were detected by metagenomic analysis technology,and the composition of grape rhizosphere microbial communities was analyzed and studied,and the correlation between microorganisms and physicochemical properties of different soil rhizosphere microorganisms was explored.The results of the study are as follows:1.The bulk density of the three kinds of soil increased with the increase of soil depth,and the specific gravity and porosity decreased with the increase of soil depth.The pH value of the three soils is above 8.2,which belongs to weak alkaline soil.The soil nutrient content was generally higher than that of the other two soil types.The results of soil enzyme activity determination showed that urease,sucrase,alkaline phosphatase and catalase enzyme activities were strong in gravel soil.The rhizosphere of all indexes was higher than that of non-rhizosphere,and the planting of Cabernet Sauvignon under all soil types could increase the water content and nutrient content of rhizosphere soil,and played a more significant role in gravel soil.2.The bacterial community structure of the three different soil types was significantly different.Among the three soil types,the number of OTUs in rhizosphere and non-rhizosphere soil bacterial communities was significantly higher than that in non-rhizosphere,and the largest increase in rhizosphere was in light limelime soil,which increased by 6.09%,and the number of bacterial communities in Cabernet Sauvignon grapes was the largest.At the phylum level,Proteobacteria and actinomycetes were found to be the most abundant bacteria in the rhizosphere soil,accounting for about 70%of the total number of bacteria.Analysis of the order level and order level also showed that y Proteobacteria,α Proteobacteria,and Actinomycetes were the dominant orders,and Burkella and rhizobia were the dominant orders.The diversity index results showed the highest species richness in gravel soils.3.The main flora at the level of the Cabernet Sauvignon rhizosphere fungal phylum are ascomycetes and mucormyces,accounting for 80%-90%of the total number of fungi;Rhizobia is the dominant genus.The Alpha Diversity Index showed that planting Cabernet Sauvignon grapes in limestone soil increased the species richness of the rhizosphere and decreased the species richness of the rhizosphere of aeolian and gravel soils.There were significant differences in the diversity of the three soil rhizosphere and non-rhizosphere colonies,and the planting of Cabernet Sauvignon had a significant effect on soil colonies,among which Cabernet Sauvignon planting in gravel soil had the greatest effect on soil flora.4.The analysis of soil factors and microbial community structure showed that the factors with the greatest influence on soil microbial bacterial community were pH,total phosphorus,available phosphorus,sucrase,aluminum and calcium.The soil environmental factors with the greatest influence on soil microbial bacterial phylum were pH and conductivity,among which organic matter,total phosphorus,available potassium and alkali-hydrolyzable nitrogen were significantly positively correlated with actinomycetes,and pH was significantly negatively correlated with actinomycetes.There was a significant correlation between fungal community and soil urease,available phosphorus,total phosphorus and calcium,soil pH and chytrid phylum had a significant positive correlation,soil alkaline hydrolyzable nitrogen,available potassium,total phosphorus and alkaline phosphatase had a significant negative correlation with ascomycetes and chytrid phylum,and positively correlated with basidiomycetes and mucormycetes.There was a significant correlation between pH,catalase,total phosphorus,organic matter and other factors and fungal genus.In summary,in gravel soils,the planting of Cabernet Sauvignon grape plants had the greatest impact on microbial community,and the most important soil factors affecting the structure and diversity of Cabernet Sauvignon rhizosphere microbial community were pH and available phosphorus.Therefore,soil type is one of the reasons for the difference in soil microbial community structure and diversity.