Effect of phosphorus deficiency on acid phosphatase and phytase activities in common bean (Phaseolus vulgaris L.) under symbiotic nitrogen fixation
Résumé
Changes growth, symbiotic nitrogen fixation (SNF), acid phosphatase (ACP). and phytase activities to phosphorus availability (15 and 60 mu mol KH(2)PO(4) plant(-1) week(-1)) were compared in two recombinant lilies (115 and 147) of common bean. Plant growth. nodulation and SNF were genotype and P level-dependent. 147 was more affected by 1) shortage (15 mu mol P) than 115. Four ACP types were revealed ill the nodules of both lilies, ACP1 exhibiting a higher specific activity under P shortage as compared to the 60 mu mol P treatment, especially in 115. A single phytase was revealed for the nodules of both lilies and was significantly enhanced by 11 deficiency. Three ACT types were found ill roots and leaves. showing increasing activity Under P deficiency. especially ill 115. Regardless of P supply, leaf ACP specific activity was higher than that of nodules and roots ill the both lilies. Interestingly. phosphorus Use efficiency for N(2) fixation significantly correlated to module ACP activity Under P shortage in the both lilies. Vile relatively better performance of 115 as compared to 147 under 1) deficiency could he partly ascribed to the ability of 115 to maintain higher ACP activity. This enzyme might fie involved ill the remobilization of the plant Pi and its utilization for SNF.