Biolog Phenotypic And Transcriptome Analysis On Different Pathogenic Strains Of Colletotrichum Gloeosporioides

Colletotrichum gloeosporioides is an important fungal pathogen of Colletotrichum genus,with a wide range of host types,it is the worldwide disease.Colletotrichum gloeosporioides can infect a variety of important agricultural and forestry economic crops and cause important economic losses in China.In this paper,the pathogenic of 21 strains of Colletotrichum gloeosporioides isolated from different hosts in different regions was determined.Biolog phenotypic analysis and transcriptome analysis were performed on strong,medium and weak representative strains,and the differences in pathogenicity were analyzed from physiological,biochemical and molecular perspectives.The results are as follows :1 The Colletotrichum gloeosporioides pathogenic determinationIn this study,21 strains of Colletotrichum gloeosporioides isolated from different hosts were used as the research objects,and the inoculation experiment of Colletotrichum gloeosporioides on the pepper of cultivar Yanjiao 425 was conducted.Finally,Colletotrichum gloeosporioides was divided into 12 strong pathogenic strains,5moderate pathogenic strains and 4 weak pathogenic strains.2 Biolog phenotypic analysisOne representative strain was selected from each of the three species of pathogenic strains,and the three pathogenic strains were compared and analyzed from three aspects of metabolic utilization of carbon and nitrogen sources,material synthesis pathway and sensitivity to chemical substances.The results showed that the strong pathogenic strains could use more kind of carbon and nitrogen sources and higher metabolic utilization,and the strong pathogenic strain metabolizes 31 carbon source substances and 25 nitrogen source substances more than the other two pathogenic strains.In the determination of biosynthetic pathway,the chemical substances used by the three strains together have a higher promotion effect on the strong pathogenic strains than the other two strains.In the determination of sensitivity to chemical substances,the sensitivity of moderately pathogenic strains and weakly pathogenic strains to antibiotics is higher than that of highly pathogenic strains.3 Transcriptome sequencing analysis of different virulence strains of Colletotrichum gloeosporioidesMycelium of three pathogenic strains were analyzed by transciptome,the quantitative real-time PCR was used to explore the correlation of transcriptional level.The hyphal transcriptome sequencing results of three pathogenic strains showed that a total of 2,702,2,236 and 1,537 differential genes,and the up-regulated differentially expressed genes were 1,369,1,284 and 695,the down-regulated differentially expressed genes were 1,333,952 and 842.The GO function analysis of differentially expressed genes showed that the three groups enriched with the largest number of genes were all molecular functional categories,followed by cellular component categories,and finally biological process.In each functional category,the number of genes enriched by almost strong pathogenic strains was higher than that of weak pathogenic strains.KEGG analysis of differentially expressed genes showed that the three groups were respectively enriched to 108,103 and 83 pathways,the pathways with the largest number of enriched genes were metabolic pathways,and the differentially expressed genes were 546,347 and 180.Eight genes including cat B,LAC1 and ALDH were screened out of the TOP20 genes among the differentially expressed genes for subsequent verification by q RT-PCR.4 Transcriptome sequencing analysis of Colletotrichum gloeosporioides in the diseased tissue of Yanjiao 425Mycelium of Colletotrichum gloeosporioides in the diseased tissue of Yanjiao 425 were analyzed by transciptome,the quantitative real-time PCR was used to explore the correlation of transcriptional level.The hyphal transcriptome sequencing results of three pathogenic strains infecting the diseased part of pepper showed that a total of2,329,1,880 and 967 differential genes,and the up-regulated differentially expressed genes were 1,435,1,101 and 530,the down-regulated differentially expressed genes were 894,779 and 437.The GO function analysis of differentially expressed genes showed that the three groups enriched with the largest number of genes were all molecular functional categories.KEGG analysis of differentially expressed genes showed that the three groups were respectively enriched to 109,74 and 98 pathways,the pathways with the largest number of enriched genes were metabolic pathways,and the differentially expressed genes were 351,123 and 273.Eight genes including ace A,PMG and Cx were screened out of the TOP20 genes among the differentially expressed genes for subsequent verification by qRT-PCR.