Functional Research Of SIX2and SIX6homologous Ene From Fusarium Oxysporum F.sp.cubense

Fusarium oxysporum is a harmful agricultural production plant pathogenic fungi, their different biotypes can infect bananas, melons, legumes, solanaceae, cotton and more than100different kinds of crops. Banana wilt pathogen Fusarium oxysporum f.sp.cubense,as a typical soil-borne diseases, which spread through the soil, it is difficult to control. Currently, the pathogenesis research of banana wilt disease was less, making its hard to targeted prevention. Functional studies on Fusarium oxysporum f.sp.cubense related genes can deepen our understanding of the pathogenic mechanisms, thereby providing new ideas for pathogen control.Fusarium oxysporum in the interaction secret into the xylem inrich low molecular weight proteins which is called SIX protein. To understand its role in pathogenesis of Foc, the DNA fragments from the upstream and downstream of open read frame were amplified by PCR, respectively. They were cloned into the pCT74to construct the vector for homologous recombination, then was transferred into Foc B2strain by the PEG-Mediated Protoplast Transformation. At last, several transformants with seletcion marker of GFP and hph cassette were obtained. Among them, some transformants were confirmed to be the FoSIX2and FoSIX6gene-deletiong mutants by PCR with four pairs of the gene-specific primers, phenotype mutant analysis found that mutant AFoSIX2and AFoSIX6colony growth rate slower than wild type, AFoSIX6mutant only the1/4wild-type sporulation, and can not grow in high osmotic environment.Virulence determination was found that mutant AFoSIX2and AFoSIX6not penetrate cellophane AFoSIX2and AFoSIX6gone on living tissue colonization, AFoSIX2and AFoSIX6fixed significantly reduced reproductive capacity.By measuring enzyme activity was found, Complement of AFoSIX2and AFoSIX6mutant with the original gene, the pathogenicity and biologic characteristics of complementary strain were recovered.In this study, We preliminarily elucidated functions identification of FoSIX2snd FoSIX6,laid the foundation for further reveal the pathogenesis of banana wilt disease, the next step required for protein physicochemical properties and on the basis of mutual respect for research.