Search

Bacterial wilt, caused by the Ralstonia solanacearum species complex, is one of the most damaging bacterial diseases in tobacco and other Solanaceae crops. In this study, we conducted an analysis and comparison of transcriptome landscape changes in seedling roots of three tobacco BC4F5 lines, C244, C010, and C035, with different resistance to bacterial wilt at 3, 9, 24, and 48 h after R. solanacearum infection. A number of biological processes were highlighted for their differential enrichment between C244, C010, and C035, especially those associated with cell wall development, protein quality control, and stress response. Hence, we performed a genome-wide identification of seven cell wall development-related gene families and six heat shock protein (Hsp) families and proposed that genes induced by R. solanacearum and showing distinct expression patterns in C244, C010, and C035 could serve as a potential gene resource for enhancing bacterial wilt resistance. Additionally, a comparative transcriptome analysis of R. solanacearum-inoculated root samples from C244 and C035, as well as C010 and C035, resulted in the identification of a further 33 candidate genes, of which Nitab4.5_0007488g0040, a member of the pathogenesis-related protein 1 (PR-1) family, was found to positively regulate bacterial wilt resistance, supported by real-time quantitative PCR (qRT-PCR) and virus-induced gene silencing (VIGS) assays. Our results contribute to a better understanding of molecular mechanisms underlying bacterial wilt resistance and provide novel alternative genes for resistance improvement. [ABSTRACT FROM AUTHOR]

The TIFY gene family plays an essential role in plant development and abiotic and biotic stress responses. In this study, genome-wide identification of TIFY members in tobacco and their expression pattern analysis in response to Ralstonia solanacearum infection were performed. A total of 33 TIFY genes were identified, including the TIFY, PPD, ZIM&ZML and JAZ subfamilies. Promoter analysis results indicated that a quantity of light-response, drought-response, SA-response and JA-response cis -elements exist in promoter regions. The TIFY gene family exhibited expansion and possessed gene redundancy resulting from tobacco ploidy change. In addition, most NtTIFY s equivalently expressed in roots, stems and leaves, while NtTIFY1 , NtTIFY4 , NtTIFY18 and NtTIFY30 preferentially expressed in roots. The JAZ III clade showed significant expression changes after inoculation with R. solanacearum , and the expression of NtTIFY7 in resistant varieties, compared with susceptible varieties, was more stably induced. Furthermore, NtTIFY7 -silenced plants, compared with the control plants, were more susceptible to bacterial wilt. These results lay a foundation for exploring the evolutionary history of TIFY gene family and revealing gene function of NtTIFY s in tobacco bacterial wilt resistance. • Thirty-three NtTIFY genes were identified in tobacco and grouped into four subfamilies. • The JAZ III clade was highly induced under the infection of R. solanacearum and treatment with Me-JA. • NtTIFY7 contributes to resistance against bacterial wilt in tobacco. [ABSTRACT FROM AUTHOR]