Abstract
Polyamines (PAs) are ubiquitous organic polycations in living cells. They are necessary for the successful replication of cells and the regulation of senescence and morphogenesis in higher plants. Recent studies also showed that various environmental stresses such as high osmotic pressure, low temperature and plant-microbe interaction caused the increase in endogenous PAs. Leguminous roots are infected and nodulated by rhizobia as a result of legume-rhizobium symbiotic association. In the present study, we examined the change in the PA contents in plant organs of Glycine max cv. Enrei after rhizobia infection. Rhizobia inoculation resulted in the increase of putrscine and cadaverine content in the roots and leaves after one day of the treatment. The external application of these PAs on the leguminous plants significantly influenced the root development and nodule production. These data indicted possible involvement of PAs in the regulation of nodule formation.
