College of Horticulture and Landscape Architecture, Henan Institute of Science and Technology, Xinxiang, Henan, PR China.
Henan Provincial Research Center for Horticultural Plant Resource Utilization and Germplasm Innovation Engineering, Henan, Xinxiang, China.
PeerJ. 2023 Apr 21;11:e15177. doi: 10.7717/peerj.15177. eCollection 2023.
Waterlogging caused by short and severe, or prolonged precipitation can be attributed to global warming. Pumpkin plants are drought-tolerant but not tolerate to waterlogging stress. Under frequent rain and waterlogging conditions, the production of pumpkins is of lower quality, sometimes rotten, and harvest failure occurs in severe cases. Therefore, it is of great significance to assess the waterlogging tolerance mechanism of pumpkin plants. In this study, 10 novel pumpkin varieties from Baimi series were used. The waterlogging tolerance level of pumpkin plants was evaluated by measuring waterlogging tolerance coefficient of biomass and physiological indices using waterlogging stress simulation method. The criteria to evaluate the waterlogging tolerance capacities of pumpkin plants were also explored. Using principal component and membership function analysis, waterlogging tolerance levels of the pumpkin varieties were ranked as follows: Baimi No. 10>; Baimi No. 5>; Baimi No. 1>; Baimi No. 2>; Baimi No. 3>; Baimi No. 7>; Baimi No. 9>; Baimi No. 6>; Baimi No. 4>; Baimi No. 8. Based on the results, Baimi No. 10 was identified with strong waterlogging tolerance and Baimi No. 8 with weak waterlogging tolerance. The responses of malondialdehyde (MDA), proline, key enzymes responsible for anaerobic respiration, and antioxidant enzymes to waterlogging stress were studied in pumpkin plants. The relative expression levels of related genes were determined using real-time fluorescence quantitative PCR technique. The aim of our study was to assess the waterlogging tolerance mechanism of pumpkin plants, thus laying a theoretical foundation for breeding waterlogging-tolerant varieties in the future. After flooding stress treatment, the antioxidant enzyme activities, contents of proline and alcohol dehydrogenases of Baimi No. 10 and Baimi No. 8 displayed an increase followed by a decrease. All indices of Baimi No. 10 were higher than Baimi No. 8. MDA contents gradually increased, with the content being higher in Baimi No. 8 than Baimi No. 10. The activities of pyruvate decarboxylases (PDCs) in Baimi No. 8 and Baimi No. 10 exhibited a decrease initially, followed by an increase, and then a decrease again. The PDC activity in Baimi No. 8 was generally higher than Baimi No. 10. The relative expression levels of genes encoding superoxide dismutase, peroxidase, catalase, and ascorbate peroxidase were consistent with their corresponding enzyme activities. During the early stage of flooding stress, pumpkin plants waterlogging tolerance was improved by enhancing the expression levels of antioxidant enzyme encoding genes and increasing the antioxidant enzyme activities.
水渍由短期和剧烈或长期降水引起，这可归因于全球变暖。南瓜耐旱但不耐水渍胁迫。在频繁降雨和水渍条件下，南瓜的产量较低，有时会腐烂，严重情况下会导致收获失败。因此，评估南瓜植株的耐水渍机制具有重要意义。在这项研究中，使用了来自 Baimi 系列的 10 个新型南瓜品种。通过水浸胁迫模拟方法，测量生物量和生理指标的水浸胁迫系数，评估南瓜植株的耐水浸能力。还探索了评估南瓜植株耐水浸能力的标准。使用主成分和隶属函数分析，对南瓜品种的耐水浸水平进行了排序：Baimi No. 10>Baimi No. 5>Baimi No. 1>Baimi No. 2>Baimi No. 3>Baimi No. 7>Baimi No. 9>Baimi No. 6>Baimi No. 4>Baimi No. 8。基于这些结果，确定 Baimi No. 10 具有较强的耐水浸能力，Baimi No. 8 具有较弱的耐水浸能力。研究了水渍胁迫对南瓜植株丙二醛（MDA）、脯氨酸、无氧呼吸关键酶和抗氧化酶的响应。使用实时荧光定量 PCR 技术测定相关基因的相对表达水平。本研究旨在评估南瓜植株的耐水浸机制，为未来培育耐水浸品种奠定理论基础。在水淹胁迫处理后，Baimi No. 10 和 Baimi No. 8 的抗氧化酶活性、脯氨酸和醇脱氢酶含量先增加后减少。Baimi No. 10 的所有指标均高于 Baimi No. 8。MDA 含量逐渐增加，Baimi No. 8 高于 Baimi No. 10。Baimi No. 8 和 Baimi No. 10 的丙酮酸脱羧酶（PDCs）活性先下降后上升，然后再次下降。Baimi No. 8 的 PDC 活性普遍高于 Baimi No. 10。编码超氧化物歧化酶、过氧化物酶、过氧化氢酶和抗坏血酸过氧化物酶的基因的相对表达水平与其相应的酶活性一致。在水淹胁迫的早期阶段，通过增强抗氧化酶编码基因的表达水平和增加抗氧化酶活性，提高了南瓜植株的耐水淹能力。
