Role of PGPR in Rice Fields of Bihar

Currently, the rising human race drives massive load on agricultural field for enhancing crop yield and sustainable agro-ecosystem at global level that chiefly turn to extreme utilization of synthetic fertilizers, but indiscriminate use of fertilizers has triggered soil infertility and affect crop productivity. PGPR are the soil-dwelling bacterium that facilitates plant growth and reduce the risk of chemical fertilizers. Weeds are undesirable, non-valuable plant that compete with main crops, reduce their growth and yield and affect soil fertility, yet their rhizospheric zone accommodate countless PGPR (Arthrobacter, Pseudomonas, Burkholderia, Serratia, Bacillus); a source of PGP traits. One of the PGP trait is Phosphate solubilization for which Eclipta alba (Bhringraja), the most common weed in the Paddy field of Aurangabad, Bihar is more relevant. The rhizospheric soil of Eclipta alba provide horizon to PGPR that stimulates growth and yield of rice cultivar and diminish dependency on chemical fertilizers through Phosphate solubilization. An assemblage of beneficial PGPR associated with Eclipta alba rhizosphere secrete organic acids that solubilize insoluble phosphate compound into soluble inorganic phosphorus to increase P-availability in the soil known as PSBs (Phosphate Solubilizing Bacteria). The novel PSBs like Bacillus, Pseudomonas and Serratia showed PS activity due to secretion of PGP substances by them and hence, act as natural biofertilizers. In this study, certain isolates were identified as Bacillus (3), Pseudomonas (5) & Serratia (7). Despite, one Bacillus strain M13; 3 Pseudomonas strains F6, K11 & N14; 2 strains of Serratia P16 and R18 were remarkably potent for PSBs in the rice field of Aurangabad, Bihar which is giving a new dimension in modern agro-ecosystem and biofertilizer. These PSBs could be used as an efficient alternative approach to chemical fertilizers to enhance soil fertility and promote growth and yield of rice cultivar.