Present study was designed to compare the effect of inoculation with freshly isolated phosphate solubilizing bacterial (PSB), to ones, used as PSB biofertilizer on microbial population viz., total bacteria, Rhizobium and PSB under in-vivo experiments with groundnut (Arachis hypogaea L.), under new alluvial and red and lateritic soils. Total bacteria count did not vary significantly due to treatment effects over un-inoculated control pots under both red and laterite and new alluvial soils. Overall, bacterial population was higher in new alluvial soil as compared to red and laterite soils. Rhizobia population also exhibited similar trends. However, for both the soils, PSB populations varied significantly, over un-inoculated control at later stages of crop growth

The field experiment was conducted with two fertigation levels (100 and 75% RD N&K) and four levels of Microbial Consortium biofertigation (MC, Azotobacter, P solubulizing bacteria, K releasing bacteria and Zn solubulizing bacteria) at Water Technology Centre, College of Agriculture, PJTSAU, Rajendranagar, Hyderabad during rabi 2018-19 on maize (Zea mays L.). Randomized Block Desing (RBD) with 3 replications was used for this experiment. The maximum grain yield (7254 and 7304 kg ha-1) was obtained with fertigation of 100% RD N&K and biofertigation of MC five times. Also, the interaction effect was not significant. Between fertigation levels maximum cost of cultivation was observed in 100% RD N&K (?75,488 ha-1) followed by 75% RD N&K (?70,917 ha-1) and in second factor, soil application of MC recorded higher cost of cultivation (?75,973 ha-1) and the minimum was observed in treatment where MC was not applied (?71,573 ha-1). Fertigation of 100% RD N&K recorded significantly higher gross and net returns (?1,32,797 and ?57,309 ha-1, respectively), whereas fertigation with 75% RD N&K recorded on par net returns (?56,151 ha-1) with 100% RD N&K and higher B:C ratio (1.91) than 100% RD N&K. Biofertigation of MC five times recorded significantly higher gross returns (?1,33,665 ha-1) over treatment where MC was not applied (?1,23,645 ha-1) and was on par with biofertigation of MC three times (?1,32,301 ha-1) and soil application of MC (?1,30,118 ha-1). Significantly, higher net returns were observed with five times and three times biofertigation of MC (?60,892 and ?59,808 ha-1) compared to soil application of MC (?54,146 ha-1) and treatment without MC application (?52,072 ha-1) which recorded lower net returns. Higher B:C ratio was observed with five times MC biofertigation (1.84) and three times MC biofertigation (1.83). Significantly Lower B:C ratio was observed in soil application of MC (1.71) and treatment without application of MC (1.73).