Abstract
Plants have strategies to adapt phosphorus (P) deficiency and aluminum (Al) stress by secreting some low molecular weight metabolites from roots. Organic acid secretion from plant roots into the rhizosphere plays an important role in insoluble P mobilization and Al detoxification. However, there was few study on comprehensive analysis about root exudates involved in each stress and combination of them. Therefore, in this study, we investigated profiles of Arabidopsis root exudates under stressed conditions with the combination of P and Al treatments.
Arabidopsis (Col-0) was cultivated under P sufficient (+P) and deficient (-P) conditions for 19 days on 1/2 MS media. Root exudates were collected in water 0 or 10 µM Al for 3h, and used for the comprehensive analysis of low-molecular weight organic compounds by GC/MS. Many amino acids and sugars were increased by both -P and Al stress. Among organic acids, malic, fumaric and succinic acids were increased by both -P and Al stress. On the other hand, citric and lactic acids increased by only -P. These results suggested that the profiles of root exudates were different but related between -P and Al stress.
