Study On The Prevention And Control Effect Of Microbial Inoculants Covered With Straw On Banana Fusarium Wilt

Fusarium wilt of banana is an important and devastating soil-borne disease,which is mainly caused by the Fusarium oxysporum f.sp.cubense.The comprehensive prevention and control with microbial inoculants as the core has become the most important prevention and control technology at present,Explore how to improve the colonization and bacteriostatic ability of biocontrol bacteria in soil under banana straw mulching mode,so as to achieve the purpose of improving the control effect.Based on this,this paper takes the important tropical fruit banana and its important disease banana fusarium wilt as the research object,through the outdoor pot experiment to simulate the field,the pot plant growth status,rhizosphere soil physical and chemical properties,crops,microbial population structure under different treatment modes Research on differences to analyze the correlation between the differences of beneficial and harmful microflora and the occurrence of crop diseases,Analysis of the effect of banana straw mulch combined with microbial bacterial fertilizer on the occurrence of banana wilt disease.Provides a practical basis and scientific basis for the application and promotion of compound microbial bacterial manure and banana straw in situ mulching in the prevention and control of banana wilt disease,and also provides a new direction for the prevention and control of soil-borne diseases and the increase of crop yield in hot areas.The research results are as follows:(1)The microscopic technique was used to investigate the antagonistic mechanism of the antagonistic Bacillus,which is an important part of the compound microbial fertilizer.Through scanning electron microscope observation,it was found that the crude extract of the fermentation broth of the antagonistic Bacillus in the bacterial agent caused the Foc4 surface to be rough,shrunken,deformed Swollen node deformity,spore hypoplasia.Transmission electron microscopy was used to observe that the crude extract damaged the Foc4 cell membrane and organelles,lysing the cell walls.(2)Establish soil amplification technology for gene monitoring of antagonistic Bacillus lipopeptide antibiotics,amplify lipopeptide antibiotic genes of 20 strains of Bacillus deposited in the laboratory,including strain X5 etc,the type and abundance of lipopeptide antibiotic genes are positively correlated with the pathogenic fungi’s inhibitory ability.Bacillus,whose crude extract of fermentation broth has a high inhibitory effect on Foc4,all synthesize antibiotic-related genes of Bacillomycin,Fengycin,Iturin,and Surfrin.Screening primer pairs Bam A-F1/R1(250 bp),Fen BF2/R2(184 bp),Itu C-F2/R2(200 bp),Srf AA-F2/R2(164 bp)for semi-quantitative monitoring of lipopeptide antibiotic gene abundance in soil Degree of primer.The amplification of soil genomic DNA proves that lipopeptide antibiotic synthesis genes are feasible in soil monitoring.(3)Through the pot experiment,the application of microbial bacterial fertilizer treatment under the cover of banana straw,the gene abundance of lipopeptide antibiotics was significantly higher than that of treatment with only bacterial fertilizer.Colonization of the active ingredient in the soil.And the traditional coating plate counting method can’t reflect this feature.(4)Banana straw mulching and application of microbial bacterial fertilizers antagonizes and inhibits pathogens in the soil and reduces the incidence of disease: the composite model can effectively promote the growth and development of banana seedlings,greatly control the disease status of banana wilt,and its disease index is only11.1,the prevention effect can reach 88.6%,which is significantly higher than that of71.66% and 43.31% which were only treated with bacterial fertilizer and covered only.(5)The application of bacterial manure under the cover of banana straw can also effectively increase soil fertility and adjust soil p H,so that the soil organic matter and available nitrogen under the treatment have the highest indicators.Straw coverage can effectively alleviate the impact of high temperature weather on soil temperature and increase soil fertility.In short,through the research in this article,The application of bacterial fertilizer can effectively increase the number of spores and bacteria that can be cultivated in the soil,and it can obviously inhibit the pathogen of banana wilt disease.The covering treatment can effectively promote the effectiveness of bacterial fertilizer.Therefore,in agricultural production,the combination of bacterial manure and mulch mode is the best choice.