Flooding Stress in Plants

Abstract

As sessile organisms, plants cannot run away from unfavourable growth conditions. In order to survive stress conditions, for example flooding stress, they have evolved multiple adaptational mechanisms. Flooding stress restricts gas diffusion in and out of the plant cells, and subsequently leads to oxygen deficiency inside the plants. Plants can react to flooding with two strategies. On one hand, they can avoid the occurrence of oxygen deficiency inside by anatomical and morphological adaptations. These adaptations are mainly mediated by the gaseous plant hormone ethylene. On the other hand, they can also survive with oxygen deficiency, at least for some time. This adaptation includes the rearrangement of primary metabolism, for example through induction of fermentation. This transcriptional rearrangement is mediated by a set of transcription factors whose protein abundance directly depends on the oxygen concentration inside the plant cells. Key Concepts Flooding reduces gas diffusion and thus oxygen and carbon dioxide availability within plant tissues. Several plant species have adapted to flooding conditions and can survive and even grow under water. One strategy to survive flooding is the avoidance of oxygen deficiency within plant tissues by morphological changes. Morphological changes include aerenchyma formation, adventitious roots, leaf hyponasty and shoot elongation. Morphological changes are largely mediated by the gaseous plant hormone ethylene that naturally accumulates in plant parts under water. A second strategy to survive flooding is the adaptation to oxygen deficiency by metabolic rearrangements. Metabolic rearrangements include induction of fermentation, glycolysis and starch degradation. Metabolic rearrangements are partially mediated by a group of oxygen‐labile transcription factors that accumulate under oxygen deficiency.

Slip‐Stacked J‐Aggregate Materials for Organic Solar Cells and Photodetectors

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Keeping the shoot above water – submergence triggers antithetical growth responses in stems and petioles of watercress (Nasturtium officinale)

“…Submergence promotes internode elongation in watercress, Nasturtium officinale (Ridge, 1987; Mustroph, 2018b) , an auto‐tetraploid and non‐rosette‐growing Brassicaceae species with a natural habitat near rivers and streams (Howard & Lyon, 1952; Bleeker et al , 1999). Current mechanistic knowledge on internode elongation is strongly biased towards the monocot rice, whereas research on internode elongation in dicots remains limited to the flower stalk of the rosette‐growing species Rorippa amphibia (Akman et al , 2012).…”