Isolation And Identification Of Anthracnose Pathogen And Cloning And Analysis Of NBS-LRR Type Resistance Gene In Jute

Jute is a natural fiber crop and an important raw material in spinning industry,which is often affected by many kinds of diseases.Colletotrichum Corchori is one of the diseases,and it can reduce the production of jute seriously.So it is necessary to have a comprehensive study on jute anthracnose pathogen species.In this study,we conducted experiments on identification of Corchorus capsularis anthracnose pathogens,identification of a set of 144 recombinant inbred lines(RIL)derived from crossing 179 and wild species,cloning and analysis of NBS-LRR type gene analogs.The main results were as follow:(1)Identification of the pathogenThe samples of infected Corchorus capsularis were collected and isolated from Zhejiang,Fujian,Guangxi,Henan provinces of China.morphology analysis,gene sequences of rDNA-ITS,LSU,β-Tub2 were analyzed using molecular biology method.Corchorus capsularis anthracnose pathogens has two types,one is C.dematium,another is C.gloeosporioides.(2)Pathogenicity testIn order to identify the pathogenicity,these seven strains were inoculated on the stems of jute cultivar Funong No.1.The results showed there were some differences between the tested pathogenic strains.In general,the pathogenicity of C.dematium was stronger than C.gloeosporioides.(3)Identification of resistanceFJ2 strain was the strongest pathogenic species.The strains were inoculated on 144 jute germplasm with wound respectively in the field.The result showed large differences among different strains,and the size of the lesion was from 11.79 mm to 30.50mm,RI-98(11.79mm),RI-45(11.87mm)and RI-76(12.69mm)were germplasm with high resistance,while RI-13(30.50mm),RI-108(29.61mm)and RI-61(28.77 mm)were sensitive to anthracnose.(4)Cloning and analysis of NBS-LRR type gene analogsThree resistance gene analogues(RGAs)of NBS were isolated from the genome of RI-98 by polymerase chain reaction(PCR)according to homology cloning method.Sequence analysis showed that RGA contained four conserved motifs of NBS including P-loop,kinase-2a domain,kinase-3 a domain and HD,which might be related with anthracnose resistance of jute.