Waterlogging is one of the major environmental challenges that can adversely impact squash growth, development, and productivity. Nevertheless, studies on the physiological changes of squash to waterlogging stress are scarce. Previously, we reported that the Cucurbita moschata (Cmo) Early Price (Ep) cultivar showed higher chlorophyll content (CC) and spectral reflectance compared to the Cucurbita maxima (Cma) OK-101 (Ok) cultivar after waterlogging. In the present work, we further examined more physiological parameters in eight cultivars of Cmo and Cma, and studied whether these non-destructive indices could efficiently identify various waterlogging-tolerant genotypes and were consistent with visual evaluations. Moreover, we investigated the effects of waterlogging on the antioxidant system of cucurbit species, and evaluated dynamic changes occurring in these plants during varying waterlog periods by determining physiological characteristics. The activity of ascorbate peroxidase (APX) and superoxide dismutase (SOD) showed a significant increase in Ep plant leaves and roots after 72 h and 6 h of waterlogging, respectively, compared to Ok plants. In addition, Ep exhibited a higher tolerance to waterlogging than Ok in terms of enhanced root length, values in CC, spectral reflectance, and APX and SOD activity, plus decreased levels of electrolyte leakage, 2,2‑diphenyl‑1‑picrylhydrazyl free radical scavenging, and hydrogen peroxide levels. This study provides a comprehensive understanding of the physiological variations in response to waterlogging stress and can potentially be used to breed cucurbit species with waterlogging tolerance for a wetter future climate.

涝灾是主要的环境挑战之一，会对南瓜的生长、发育和生产力产生不利影响。然而，关于南瓜对涝害胁迫的生理变化的研究却很少。此前，我们报道过，与Cucurbita maxima相比， Cucurbita moschata (Cmo) Early Price (Ep) 品种表现出更高的叶绿素含量 (CC) 和光谱反射率(Cma) OK-101 (Ok) 品种涝后。在本工作中，我们进一步检测了Cmo和Cma的8个品种的更多生理参数，并研究了这些无损指标是否能够有效识别各种耐涝基因型并与视觉评估一致。此外，我们还研究了涝害对葫芦科植物抗氧化系统的影响，并通过确定生理特征来评估这些植物在不同涝期期间发生的动态变化。与Ok植物相比，浸水72小时和6小时后，Ep植物叶片和根部的抗坏血酸过氧化物酶（APX）和超氧化物歧化酶（SOD）活性分别显着增加。此外，在根系长度增加方面，Ep比Ok表现出更高的耐涝性，CC、光谱反射率、APX 和 SOD 活性的值，以及电解质泄漏水平、2,2-二苯基-1-三硝基苯肼自由基清除水平和过氧化氢水平的降低。这项研究提供了对涝胁迫响应的生理变化的全面了解，并有可能用于培育具有耐涝能力的葫芦品种，以应对未来潮湿的气候。