Effect of boron and sulfur interaction on some important biological indices in an inceptisol

In most soil ecosystems, soil biological activity and associated processes are concentrated in the rhizosphere soil and is influenced by the external application of plant nutrients. The impacts of boron and sulfur on soil biological properties were evaluated in an Aeric Haplaquept (pH 5.7) growing rapeseed (Brassica campestris L.) as a test crop. Application of boron (B) at 2 mg kg(-1) in combination with sulfur (S) at 30 mg kg(-1) (B2S30) resulted in highest available Boron and sulfur of 0.239 and 15.4 mg kg(-1), respectively and registered 62.5% and 71.3% increase over control (B0S0) at 60 days of crop growth compared to individual applications. The microbial populations viz. phosphate solubilizing microorganisms (PSM) and nitrogen fixing bacteria (NFB) were the highest of 52.63 and 85.87 x 10(5) g(-1) soil, respectively, CFU in B2S30 treatment at 60 days and adjudged as the best treatment combination for enhancement of soil biological indices and seed yield.