Kiwifruit (Actinidia sp.) vines are poorly adapted to waterlogging stress. Actinidia valvata is more tolerant against waterlogging stress than Actinidia deliciosa, and the latter contains some common rootstocks that are frequently used in kiwifruit cultivation. Little is known about the responses of A. valvata genotypes against waterlogging stress and during post-waterlogging recovery. Here, we compared physiological traits of three A. valvata genotypes (KR1, KR3, and KR5) during waterlogging stress and recovery. Kiwifruit vines displayed water loss, a decline in the net photosynthetic rate, and inhibited shoot elongation during waterlogging. These three genotypes could endure long-term waterlogging owing to their unique root system configurations as well as by sustaining carbohydrate reserves in the roots. Feeder roots of KR1 vines were damaged earlier and lost water more quickly than the other genotypes. Under the same stress, KR3 formed adventitious roots more rapidly, while KR5 had an improved ability to control water loss in above-ground tissues. After reoxygenation, growth of vines was partially recovered due to water loss control, photosynthetic recovery, and carbohydrate replenishment. KR3 and KR5 recovered their growth earlier and replenished more carbohydrates than KR1 after re-aeration. During waterlogging, both the relative water content and carbohydrate levels of vines can limit the recovery efficiency after re-aeration. Our results revealed mutual and distinct responses of different A. valvata genotypes during waterlogging stress and recovery and provided more insight into the physiological basis of their adaptation to waterlogging stress.

中文翻译：

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3种猕猴桃Dunn基因型淹水及淹后恢复生理性状对比分析

奇异果 (Actinidia sp.) 葡萄藤对涝渍胁迫的适应能力较差。猕猴桃比美味猕猴桃更能耐受涝渍胁迫，后者含有一些常用于猕猴桃栽培的砧木。关于 A. valvata 基因型对淹水胁迫和淹水后恢复过程的反应知之甚少。在这里，我们比较了三种 A. valvata 基因型（KR1、KR3 和 KR5）在涝渍胁迫和恢复期间的生理特征。猕猴桃藤蔓表现出失水，净光合速率下降，并且在涝渍期间抑制了枝条伸长。这三种基因型由于其独特的根系结构以及在根中维持碳水化合物储备，可以承受长期的内涝。与其他基因型相比，KR1 葡萄藤的饲养根受损更早，失水速度更快。在相同的胁迫下，KR3 形成不定根的速度更快，而 KR5 控制地上组织水分流失的能力有所提高。复氧后，由于失水控制、光合恢复和碳水化合物补充，葡萄藤的生长部分恢复。KR3和KR5在重新曝气后比KR1更早恢复生长并补充更多的碳水化合物。在涝渍期间，葡萄藤的相对含水量和碳水化合物水平都会限制再曝气后的恢复效率。我们的结果揭示了不同 A 的相互和不同的反应。