Aquatic and terrestrial morphotypes of the aquatic invasive plant, Ludwigia grandiflora, show distinct morphological and metabolomic responses

In the context of expansion of invasive species, survival of invasive plants is conditioned by their ability to adapt. In France, the water primrose Ludwigia grandiflora, an aquatic invasive species, invades yet wet meadows, leading to a depreciation of their fodder value. Understanding its potential adaption is necessary to its management, strong differences between both morphotypes were expected. So morphological and metabolic responses to terrestrial environment were analyzed for aquatic and terrestrial morphotypes. All morphological and biomass variables were greater in the terrestrial morphotype than the aquatic morphotype, independent of conditions. In terrestrial condition, both morphotypes showed a high production of sugars in root tissues, especially in the terrestrial morphotype and both morphotypes produced a low level of amino acids in shoot tissues. All results demonstrate that the terrestrial condition seems a stressful situation for both morphotypes, which activates glycolysis and fermentation pathways to improve their survival under hypoxic stress. But, only the terrestrial morphotype has been able to adjust its metabolism and maintain efficient growth. In the future, a differential transcriptomic analysis will be carried out to confirm this result. In France, the recent invasion of wet meadows by the aquatic invasive plant Ludwigia grandiflora has led the appearance of a terrestrial morphotype. Significant results reveal that this morphotype has shown new morphological and metabolomic capabilities to endure stressful conditions due to terrestrial habitat and surprisingly supplanted the aquatic morphotype in aquatic conditions. All results demonstrated the appearance of a new morphotype having new adaptive capacities.