Identification of HsfA9 and a Network of Regulators Involved in Resistance to Bacterial Wilt under High Temperature in Tomato.

Down-regulation of VvPLL3 enhances grapevine resistance to Erysiphe necator via defense activation and cell wall remodeling.

High Expression of CpMAPK9 Increased Jasmonic Acid Levels Potentially Improving Root Rot Resistance in Codonopsis pilosula

Background: This study aimed to investigate the molecular mechanisms underlying the response of Codonopsis pilosula roots to Fusarium oxysporum infection, which causes root rot and significant economic losses, and to provide a theoretical basis for breeding resistant varieties and developing effective control strategies. Methods: Root samples of C. pilosula were inoculated with F. oxysporum and harvested across five distinct intervals (0, 6, 24, 72, and 120 h after inoculation). Transcriptome sequencing was performed on 15 samples, generating 171.65 GB of clean data. De novo assembly was used to construct unigenes, followed by functional annotation and differential expression analysis. In addition, CpMAPK9 was transiently overexpressed in C. pilosula leaves to evaluate its role in jasmonic acid (JA) biosynthesis and disease resistance. Results: A total of 94,896 unigenes were obtained. Functional analysis showed that genes involved in hormone signal transduction, the MAPK signaling pathway, and plant–pathogen interactions were consistently activated in response to infection. Among the MAPK gene family, CpMAPK9 showed significant expression changes. Transient overexpression of CpMAPK9 significantly increased JA accumulation, indicating that CpMAPK9 positively regulates JA biosynthesis and may enhance resistance to root rot. Conclusions: In conclusion, our findings indicate that CpMAPK9 actively modulates JA-mediated defense pathways in C. pilosula during F. oxysporum invasion. Our findings shed light on the intricate molecular networks that drive disease defense, offering valuable theoretical insights to guide subsequent crop improvement initiatives.

Disease-stage-associated transcriptional responses underlying bacterial wilt resistance in tobacco cultivar Yunyan 87 caused by Ralstonia solanacearum.

Bacterial wilt caused by Ralstonia solanacearum severely limits tobacco production, yet the molecular basis of resistance to vascular wilt diseases remains poorly understood. We integrated field phenotyping, pathogen isolation, and transcriptomic analyses across different disease stages to investigate root responses of the resistant tobacco cultivar Yunyan 87 at healthy, moderately infected, and severely infected stages. Disease progression was accompanied by marked root biomass loss, with fresh and dry weights reduced by approximately 60% and 70%, respectively. Transcriptomic analyses identified 994 up-regulated and 1,151 down-regulated genes at the moderate stage, and 2,158 up-regulated and 2,284 down-regulated genes at the severe stage. WGCNA identified a disease severity-associated regulatory module. Functional enrichment analyses showed that moderate infection activated stress perception and redox homeostasis, whereas severe infection strongly suppressed translation and ribosome biogenesis. Dynamic expression pattern analysis further revealed coordinated activation of phenylpropanoid metabolism and lignin biosynthesis, and synergistic induction of MAPK, salicylic acid (SA), jasmonic acid (JA), and ethylene (ET) signaling pathways, followed by progressive metabolic repression. Key transcription factor families, including WRKY, MYC2, and ERF, exhibited distinct stage-dependent expression patterns. Collectively, our results demonstrate a disease-stage-associated transcriptional reprogramming strategy that balances defense activation and metabolic restraint during bacterial wilt progression, providing valuable regulatory networks and candidate genes for breeding tobacco cultivars with enhanced resistance.

Integrated Sphingolipidomic and Transcriptomic Analysis Reveals Resistance Mechanisms to Bacterial Wilt in Peanut Varieties with Contrasting Tolerance

This multi-omics framework provides detailed lipidomic and transcriptomic signatures to identify candidate genes and lipid biomarkers for marker-assisted breeding of bacterial wilt-resistant peanut varieties.

Genome-wide characterization of the sugar transporter protein family identifies candidate genes for bacterial wilt resistance breeding in tobacco.

Sugar transporter proteins (STPs) play pivotal roles in hexose allocation and plant stress responses. However, systematic characterization of the STP family in tobacco (Nicotiana tabacum) and its involvement in Ralstonia solanacearum resistance remains unclear. In this study, 37 NtSTP genes were identified and classified into six groups, with Group VI being the most conserved and Group V exhibiting dicot-specific expansion. Gene structure and conserved motif analyses revealed that most NtSTP members possess the typical MFS_STP domain, although variations in exon-intron organization and motif composition suggested functional divergence. Tandem duplication (TD) served as the primary driver of NtSTP family expansion, and Ka/Ks values of all paralogous pairs were less than 1, indicative of purifying selection. Promoter cis-element analysis revealed a complex regulatory network involving hormone signaling (ABA, JA, SA, GA, ET), stress responses, and light signaling. RT-qPCR expression profiling revealed that ten NtSTP genes (NtSTP1, 5, 7, 21, 22, 24, 26, 27, 28, and 29) exhibited significant transcriptional upregulation upon R. solanacearum infection. Specifically, NtSTP5, NtSTP7, NtSTP21, NtSTP22, NtSTP24, NtSTP26, and NtSTP27 peaked at 12 h post-inoculation (hpi), whereas NtSTP1, NtSTP28, and NtSTP29 reached their highest expression levels at 24 hpi. By contrast, NtSTP6, NtSTP13, and NtSTP30 displayed reduced expression upon R. solanacearum infection. These expression patterns indicate functional diversification within the NtSTP family and imply that these members may be transcriptionally modulated during plant responses to R. solanacearum. The present work provides preliminary and valuable candidate gene resources that may facilitate future disease resistance breeding programs in tobacco.

Combined transcriptomics and metabolomics reveals the molecular mechanism by which rice responds to Ustilaginoidea virens infection.

The combined transcriptome and metabolome analysis revealed that plant hormone signal transduction, phenylpropanoid biosynthesis, and flavonoid biosynthesis were significantly enriched in resistant rice varieties, providing valuable information on the molecular mechanisms by which rice defends against U. virens infection.