Department of Chemical Ecology, Bielefeld University, Bielefeld, Germany.
Department of Plant Biotechnology, Bielefeld University, Bielefeld, Germany.
Physiol Plant. 2023 Mar;175(2):e13874. doi: 10.1111/ppl.13874.
With climate change, longer periods without precipitation but also heavy rains will become more frequent. Thus, understanding and predicting the implications of drought-waterlogging-redrying cycles for plants is essential. We examined the effects of such events on wheat (Triticum aestivum). We measured the impacts of subsequent water treatments (drought-waterlogging-redrying) on plant shoot and root biomass, photosynthesis and transpiration, as well as on primary metabolites and transcripts of leaves. Drought and drought followed by waterlogging severely reduced shoot and root biomass. Chlorophyll fluorescence parameters and the CO assimilation rate per unit leaf area were not affected by the treatments but, after the redrying phase, plants grown under the stress treatments showed a higher transpiration rate per unit leaf area and a lower instantaneous water use efficiency. Many organic acids of the citrate cycle were less concentrated in leaves of stressed plants, while most amino acids were more concentrated. Transcript analysis of genes involved in signalling and metabolism revealed different expression patterns. While some genes responded only to drought or drought followed by waterlogging, several genes were induced upon both treatments and some were still upregulated at the end of the redrying phase. We provide insights into how wheat responds to changes in water regimes, with some of the changes probably allowing the plants to cope with these stressors, at least to a certain degree.
随着气候变化，降水减少和暴雨将更加频繁。因此，了解和预测干旱-渍水-复干循环对植物的影响至关重要。我们研究了这些事件对小麦（Triticum aestivum）的影响。我们测量了随后的水培处理（干旱-渍水-复干）对植物地上部和根生物量、光合作用和蒸腾作用以及叶片初级代谢物和转录物的影响。干旱和干旱后渍水严重降低了地上部和根生物量。处理对叶绿素荧光参数和单位叶面积的 CO 同化率没有影响，但在复干阶段后，在胁迫处理下生长的植物表现出更高的单位叶面积蒸腾速率和更低的瞬时水分利用效率。胁迫植物叶片中的柠檬酸循环许多有机酸浓度降低，而大多数氨基酸浓度升高。参与信号转导和代谢的基因的转录分析显示出不同的表达模式。虽然一些基因仅对干旱或干旱后渍水有反应，但有些基因在两种处理下都被诱导，有些基因在复干阶段仍被上调。我们深入了解了小麦对水分条件变化的反应，其中一些变化可能使植物在一定程度上适应这些胁迫。
