Plant strategy to adapt to life in water: peculiarities of root system organization in Sagittaria sagittifolia and Alisma plantago-aquatica (Alismataceae)

The roots of aquatic plants are known to grow continuously in the low-oxygen environment, frequently encountering hypoxia, a common environmental stress that affects plant growth. Hypoxia disrupts normal physiological and metabolic processes, making necessary to adapt and maintain productivity. Studies on Sagittaria sagittifolia and Alisma plantago-aquatica (Alismataceae) have demonstrated that root aerenchyma formation is a crucial mechanism for mitigating the detrimental effects of hypoxia in both species. Alisma plantago-aquatica develops the schizogenous root aerenchyma, whereas S. sagittifolia forms a lysigenous aerenchyma. The actin cytoskeleton plays a specific role in the formation of both aerenchyma types. The differences in root aerenchyma development between S. sagittifolia and A. plantago-aquatica highlight their evolutionary adaptation to distinct aquatic environments, reflecting both their phylogenetic divergence within the family Alismataceae and high developmental plasticity.