Studies On The Resistance Rapeseed Sclerotinia Sclerotiorum With Oxalate Decarboxylase

Pathogenesis Sclerotinia sclerotiorum is a worldwide disease, can infect more than450plant species. Brassica napus L. is one of the major parastisu of which the incidence of Sclerotinia sclerotiorum can come to more than80%that causes significant damage to yield and oil quality. The research demonstrated that oxalic acid is the major pathogenic factor. OXDC(Oxalate decarboxylase, OXDC) is a oxalic acid Catabolic enzyme with Mn2-. It can decompose oxalic acid to formate with concomitant release of CO2without cofactor and do not lead to a development of additional hydrogen peroxide. Excessive ROS, especially H2O2in plant tissue, can toxicity to plant. However, the formate from oxalic acid decomposed by OXDC, can be transfer to CO2or enter into Calvin cycle by enzyme-catalyzed reaction used by plant.In the research oxdc is isolated from Flammulina velutipes, the analysis of sequence show that oxdc contains1344bp bases ORF, and codes477amino acid. Through bioin-formatics analysis and predict, we found PI=4.66, MW=50.5084kDa, and predict the sig-nal peptide cleavage site between pos.32and33, illustrate it can be transport by signal peptide. Analysis the conserved sequence of amino acid, we found it belong to the super-family of cupin proteins, contain two domains, and every domain have two conserved motifs:G(X)5HXH(X)11G and G(X)5P(X)4H(X)3N("X" is arbitrary amino acid). Construc-tion of plant expression vector, incorporation the oxdc gene into the plant genome by Ag-robacteriwm-mediated transformation and plant tissue culture technology. We get8toler-ance new plants. Detection transgenic by PCR show that it contan2positive plants. Scle-rotinia sclerotiorum infection show that it remarkable retardate the infect of pathogens contrast to control group. So it have realistic significance to research the fungal-rapeseed interaction.