Study On Rhizosphere Microorganisms Of Grape At Different Growth Stages And Dynamic Changes Of Fungi In Wine Fermentation

Rhizosphere microorganisms play an important role in plant growth,nutrient acquisition and resistance to pathogenic microorganisms.At the same time,plants can also provide nutrients for rhizosphere microorganisms through secretions and abscission.Affect the composition and structure of rhizosphere microorganisms.However,how does the structure of rhizosphere microorganisms evolve in different growth stages of grapes? These problems are still lack of systematic research.Metagenomic technology can directly obtain all microorganisms from the environment and detect and analyze them.We can study the dominant microorganisms in the rhizosphere of grapes at different growth stages and the changes of these microorganisms,so as to provide guidance for green cultivation of grape orchards.Using amplicon sequencing technology to explore the changes of microbial community in the process of natural fermentation and artificial fermentation,find the key flora affecting wine quality,and analyze the fermentation mechanism of wine.Shannon index was used to evaluate the alpha diversity of rhizosphere microorganisms in different growth stages of table and wine grapes: the alpha diversity of rhizosphere microorganisms in table grapes increased first and then decreased,and the diversity of soil microbial community in grape rhizosphere was the highest in fruit growth stage;The alpha diversity index of soil microorganisms in the rhizosphere of wine grape tended to be stable in the early stage and reached the peak in the fruit growth period;The alpha diversity of rhizosphere soil microorganisms of wine grape was higher than that of table grape;Beta diversity analysis showed that the rhizosphere microorganisms of wine making and table grape could be well distinguished in the three stages of inflorescence separation stage,flowering stage and fruit growth stage,but not in the bleeding stage and mature stage.The results of difference analysis of rhizosphere microorganisms showed that the rhizosphere soil microbial community was more active in grape fruit growth period than in other growth periods.The relative abundance of Bradyrhizobium,Pseudomonas,Mesorhizobium,Mycobacterium,Ralstonia and Stenotrophomonas was higher in the rhizosphere soil during the fruit growth period;Botrytis,Fusarium,Pyricularia and Colletotrichum are pathogens causing grape diseases and pests,and their relative abundance is higher in rhizosphere soil microorganisms at grape flowering stage.Microbial Archaea in grape rhizosphere are mainly distributed in Euryarchaeota,Thaumarchaeota and Crenarchaeota.Viruses are mainly distributed in Herelleviridae,Myoviridae,Podoviridae,Retroviridae and Sipoviridae.The results of functional analysis of soil microorganisms in grape rhizosphere showed that the relative abundance of amino acid metabolism,carbohydrate metabolism,energy metabolism and signal transduction increased first and then decreased,and the relative abundance of rhizosphere microorganisms in inflorescence separation stage was the highest;The relative abundance of synthesis,secretion and action of growth hormone was the highest in the bleeding stage and mature stage;The relative abundance of two-component system was the highest during fruit growth;The relative abundance of plant pathogen interaction was the highest at inflorescence separation stage;Antibiotic resistance genes（ARGs）: van R,bae R,emr E,emr B,van A,van T and van D accumulated during grape growth.The study on fungal microbial diversity of two fermentation methods of Marselan wine showed that: at the phylum level,it was annotated to ascomycetes and basidiomycetes;On the level of genus classification,LEfse analysis showed that the dominant bacteria of natural fermentation was Hanseniaspora,and the dominant bacteria of artificial fermentation was Saccharomyces.In the rhizosphere soil microorganisms of Marselan,the relative abundance of pathogenic microorganisms such as Fusarium,Aspergillus,Sporisorium and Pyricularia in Marselan soil is higher,while the relative abundance of Hanseniaspora and Saccharomyces in the fermentation process is higher,and the microorganisms in Marselan soil and wine are quite different.In this paper,macrogenomic sequencing technology was used to reveal the species diversity and community function differences of rhizosphere microorganisms in different growth stages of grapes.Secondly,the dynamic changes of fungal flora during natural fermentation and artificial fermentation were studied by amplicon sequencing technique,the key flora of the two fermentation methods were found,and the influence of rhizosphere microorganisms on wine was revealed.This study provides some references for the rational use of microbial resources to regulate grape growth and quality,and for the development of microbial resources to promote grape growth.