Data_Sheet_1_Transcriptome Analysis Revealed the Molecular Response Mechanism of High-Resistant and Low-Resistant Alfalfa Varieties to Verticillium Wilt.docx

Following infestation by Verticillium wilt, alfalfa (Medicago sativa L.) often shows symptoms such as disease spots, leaf loss, stem, and leaf yellowing, resulting in the decline of alfalfa yield and quality and causing significant losses to the alfalfa industry. The popularization and planting of disease-resistant varieties is the most effective method to prevent and control Verticillium wilt of alfalfa. Therefore, it is particularly important to reveal the resistance mechanism of Verticillium wilt resistant varieties of alfalfa. In this study, the physiological and biochemical indexes were measured on days 7, 14, 21, and 28 after inoculation with Verticillium alfalfae for investigating the response mechanisms of two alfalfa varieties, high-resistant WL343HQ, and low-resistant Dryland. Transcriptome sequencing of alfalfa samples infected with V. alfalfae and uninfected alfalfa samples was performed to analyze the potential functions and signaling pathways of differentially expressed genes (DEGs) by GO classification and KEGG enrichment analysis. Meanwhile, weighted gene co-correlation network analysis (WGCNA) algorithm was used to construct a co-expression network of DEGs. Inoculation with V. alfalfae significantly affected net photosynthetic rate, stomatal conductance, chlorophyll content, MDA content, JA and SA concentrations, and NO and H2O2 contents in both WL343HQ and Dryland inoculated with V. alfalfae. Most of the transcription factors in plants were classified in the WRKY, NAC, and bHLH families. WGCNA analysis showed that the number of transcription factors related to plant growth and disease resistance was higher in the corresponding modules of WL343HQ disease groups on days 7 and 28 (WVa) and (WVd) than in the corresponding modules of Dryland disease groups on days 7 and 21 (HVa) and (HVc). These findings provide data for further gene function validation and also provide a reference for in-depth studies on interactions between plants and pathogens.

紫花苜蓿（Medicago sativa L.）遭受黄萎病（Verticillium wilt）侵染后，通常会出现病斑、落叶、茎秆与叶片黄化等症状，进而导致其产量与品质下降，给苜蓿产业带来重大经济损失。推广种植抗病品种是防治苜蓿黄萎病最为有效的防控手段，因此解析抗黄萎病苜蓿品种的抗病机制显得尤为关键。本研究选取高抗黄萎病品种WL343HQ与低抗黄萎病品种Dryland为材料，在接种苜蓿黄萎病菌（Verticillium alfalfae）后的第7、14、21、28天测定其生理生化指标，以探究二者对病菌侵染的响应机制。对接种病菌与未接种病菌的苜蓿样本开展转录组测序，通过GO分类注释与KEGG富集分析，解析差异表达基因（differentially expressed genes, DEGs）的潜在功能与参与的信号通路。同时采用加权基因共表达网络分析（WGCNA）算法，构建差异表达基因的共表达网络。接种苜蓿黄萎病菌后，WL343HQ与Dryland的净光合速率、气孔导度、叶绿素含量、丙二醛（MDA）含量、茉莉酸（jasmonic acid, JA）与水杨酸（salicylic acid, SA）浓度，以及一氧化氮（NO）和过氧化氢（H₂O₂）含量均发生显著改变。植物中的多数转录因子归类于WRKY、NAC与bHLH家族。WGCNA分析结果显示，接种后第7、28天的高抗品种病害组对应模块（WVa与WVd）中，与植物生长及抗病相关的转录因子数量，高于接种后第7、21天的低抗品种病害组对应模块（HVa与HVc）。本研究结果可为后续基因功能验证提供数据基础，同时也为深入探究植物与病原菌的互作机制提供参考依据。