Role of fluorescent Pseudomonas associated with root nodules of mungbean in the induction of nodulation by the rhizobia in mungbean.

摘要

Fluorescent Pseudomonas has been reported to associate with root nodules of a number of plants and play role in plant disease suppression and increased plant growth. However their role in nodule formation is still unclear. In a gnotobiotic experiment, combined effect of two isolates each of fluorescent Pseudomonas (NAFP-19 and NAFP-32) and rhizobia ( Rhizobium vignae (NFB-103) and R. vignae (NFB-109) on nodules of mungbean was evaluated. The results showed an increase in the number of nodule primordia, mature nodules and the concentration of nitrogen and phosphorus in mungbean plants. In screen house experiment, garden soil which was naturally infested with root rotting fungi and rhizobia was used. Dual application of Pseudomonas and rhizobia in the garden soil produced greater number of nodules per plant and higher nitrogen fixation than when rhizobia were used alone. Dual application of bacteria also suppressed root rotting fungi. The results showed that nodule associated fluorescent Pseudomonas played a role in plant-rhizobia symbiosis.