Responses of symbiotic nitrogen-fixing common bean to aluminum toxicity and delineation of nodule responsive microRNAs.

ABSTRACT: Aluminum (Al) toxicity is widespread in acidic soils where the common bean (Phaseolus vulgaris), the most important legume for human consumption, is produced and it is a limiting factor for crop production and symbiotic nitrogen fixation. We characterized the nodule responses of common bean plants inoculated with Rhizobioum tropici CIAT899 and the root responses of nitrate-fertilized plants exposed to excess Al in low pH, for long or short periods. A 43-50% reduction in nitrogenase activity indicates that Al toxicity (Alt) highly affected nitrogen fixation in common bean. Bean roots and nodules showed characteristic symptoms for Alt. In mature nodules Al accumulation and lipoperoxidation were observed in the infected zone, while callose deposition and cell death occurred mainly in the nodu

SUBMITTER: Mendoza-Soto AB 

PROVIDER: S-EPMC4519678 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature