Analysis Of Resistance In Transgenic Rice With OsDUF500 Gene To Xanthomonas Oryzae Pv. Oryzae And Drought Tolerane In Transgenic Tobacco With OsWRKY30 Gene

Our study showed that OsDUF500 was an up-regulated gene, which was associated with disease resistance in rice on the base of microarray. In this study, conserved functional region of DUF500 was cloned by PCR from cDNA of transgenic rice NJH12, which encoding DUF500 family of unknown function. Mature embryos of rice cultivar R109 precultured were infected and transformed by Agrobacterium tumefaciens strain EHA105/ABD::pVec8. The resistant calli were transferred into the differentiation medium down-expression plants were regenerated as numbers of Hpt-resistant calli produced. Compared with the wild type, the down-expression lines ABD showed reduced plant height, shorter leaf, white blighted grain. Disease assays of transgenic rice plants infected by Xanthomonas oryzae pv. oryzae (PXO99) indicated that different lines of transgenic rice had different resistance on rice leaf blight, compared with wild type, lesion length of the down-expression lines reduced significantly and lesion area all bellowed 30%, lesion areas of the ABD-3 and ABD-5 were 12.3% and 15.7%, respectively. Here we predicted OsDUF500 gene maybe was a negative regulator on bacterial blight resistance.OsWRKY30 is a member of WRKY transcription factor family in rice. It has two WRKY domains and belongs to Groupâ… of WRKY family. WRKY30 gene was cloned from the rice, named OsWRKY30.Using the EHA105 carrying the vectors which contain over-expression and down-expression OsWRKY30, the tobacco leaf discs were transformed. PCR and PCR-Southern analysis indicated OsWRKY30 had been integrated into tobacco genome, RT-PCR analysis of transgenic plants confirmed that OsWRKY30 gene had been expressed in transgenic tobacco plants at transcription level. Drought tolerance analysis of TO generation transgenic tobaccos showed that under the same drought stress condition, the chlorophyll content, the soluble sugar content and the free proline content of over-expresses plant UWN were higher than down-expression plant UAEBN and the WT tobacco. After 10 days without watering, the soluble sugar content of UWN was significantly higher than UAEBN and WT tobacco. After 13 days without watering, compared to WT tobacco, the free proline content and the MDA content of over-expression plant UWN were significantly different. In this study, the results showed that the resistance of transgenic tobacco of over-expression OsWRKY30 to drought tolerance was enhanced.