Studies On FSTF Gene Function Of Colletotrichum Hroii And Detection Of Defense Enzymes Of The BnWRKY75 Transformants

Persimmon anthracnose is an important disease of persimmon caused by Colletotrichum horii. It is a destructive disease of persimmon and can cause great economic losses. There are two stages in the infection process of C. horii to persimmon:biotrophic stage and necrotrophic stage. During the biotrophic stage, C. hroii penetrated the host cell walls, but did not continue to penetrate the plasma membrane of host to kill host cells. An interfacial matrix separated the plasma membrane of host and C. horii. It is conjectured that the FSTF (fungal specific transcriptional factor) gene of C. horii may be associated with the biographic stage, but this conjecture still lacks experimental evidence. In this research, a series of primers was designed to clone the left-arm and right-arm of FSTF gene of C. horii. The left-arm primers introduced EcoR I and BamH I restriction sites. The right-arm primers introduced Pst I and Hind III restriction sites. The hygromycin resistance gene was also cloned with primers introducing Xba I restriction sites. All the senqences were obtained by PCR and cloned into the pMD 19-T vector. After digestion with corresponding enzymes, they were cloned into the pCAMBIA-1300 vector by the sequence of left-arm, hygromycin resistance gene and right-arm, and a C. horii FSTF gene knock-out vector (pCAMBIA-1300-H-L-R) was obtained.WRKY75 is a member of the WRKY transcription factor family of plants. Sclerotinia sclerotiorum is a dangerous fungal pathogen of rapeseed and can cause serious damage to this crop. It was reported that the transcript abundance of WRKY75 of rapeseed (BnWRKY75) dramatically increased when rapeseed was attacked by S. sclerotiorum. However, the role of BnWRKY75 is still unclear in the response of rapeseed to S. sclerotiorum. Our laboratory has obtained some BnWRKY75 sense-transformed and antisense-transformed rapeseed plants. In this research, the activities of some defense enzymes including β-1,3-glucanase, chitinase and L-phenylalanine ammonia-lyase in the rapeseed tansformants before and after infection by S. sclerotiorum were detected. The experimental results showed that antisense-transformation with BnWRKY could increase the β-1,3-glucanase and L-phenylalanine ammonia-lyase activities of rapeseed during the infection by S. sclerotiorum.