Effect of rhizobial isolates and nitrogen fertilizer on shisham (Dalbergia sissoo Roxb.) soil properties

A treatment combination of isolates and N-based fertilizer was observed for effect on the rhizospheric soil of Dalbergia sissoo. Various blends of two plant growth-promoting rhizobacteria (PGPR1 and PGPR2) and nitrogen fertilizers (Treatments T1 to T10) have been applied to analyze their effects on the rhizospheric soil’s microbial count, physicochemical properties, and available soil NPK contents. The treatments did not produce any significant changes in the soil’s pH, electrical conductivity, or organic carbon content. However, a significant increase was observed in the nitrogen, phosphorus, and potassium contents of the rhizospheric soil, with the highest increase observed in soil treated with treatment T4, composed of the two rhizobacterial isolates utilized in this study.