Transformation Of The Transcription Factor BnWRKY75Gene Of Brassica Napus And Check Of The Disease Resistance Ability Of The Transformants

Rapeseed (Brassica napus L.) is an economically important crop in China. However, it is susceptible to a variety of pathogens. Among the pathogens, Sclerotinia sclerotiorum which causes stem rot, has potential to cause significant yield losses to rapeseed. In addition, many viruses including tobacco mosaic virus (TMV) can also infect rapeseed.WRKY proteins belong to a super-family of zinc finger proteins. Previous studies have demonstrated that WRKY transcription factors are important in plant defense response. In our study we identified BnWRKY75and cloned its coding region in both sense and antisense directions into a plant binary vector pBin438. The recombinant vectors were used to transform rapeseed cotyledons by Agrobacterium-mediated transformation method and some sense-transformed and antisense-transformed rapeseed plants have been acquired. The transformants were verified by PCR and Real-Time PCR.To further identify the function of BnWRKY75, we tested the sensitivity of the sense and antisense transformants to infection by S. sclerotiorum and TMV. Real-Ttime PCR was employed to detect the expression level of genes of BnWRKY75, BnWRKY40and PRl in the rapeseed transformants after inoculated by S. sclerotiorum. The results indicated that BnWRKY75was a negative regulator in the resistance to S. sclerotiorum. Real-Time PCR was also taken to test the expression level of TMV coat protein gene in leaves of the rapeseed transformants after inoculation with TMV and no obvious influence was observed.The P-1,3-glucanase activity of sense-transformed and antisense-transformed rapeseeds was detected. The β-1,3-glucanase activity of antisense transformants was found to be increased compared with the wide type.