Effect of nutrient sources and inoculation of phosphate solubilizing microorganisms on growth enhancement in maize

Phosphorus Solubilizing Microorganisms (PSM) can effectively contribute together in plant nutrient availability. The aim of this investigation was to evaluate the potential of isolated and procured PSM in their phosphate solubilizing capacity and improvement in growth and nutrition in maize upon inoculation with various doses of nutrient sources. Therefore, two isolated PSM strains from phosphorus deficient rhizospheric soils were tested in vitro for P solubilizing capacity along with two bacterial stains. Aspergillus sp. proved to be the superior nutrient solubilizer in both plate and broth assays. A pot culture experiment was conducted under glass house condition where plant growth and nutrient availability to the plants were observed. Hence, all 15 treatment combinations such as the four isolate inoculated plants, two nutrient sources, controls and a combination of PSM + nutrient sources with three replications were destructively sampled at 60 DAS. Both PSM inoculation and nutrient application and their combinations had synergistic effects on plant growth and nutrient uptake. Plants treated with Aspergillus sp. + RP @ 40 kg/ha increased N, P and K uptakes 1.74, 0.29 and 1.07 g /plant, respectively against control. Overall the fungal species upon inoculation with nutrient source proved to be better for plant nutrition than the bacterial ones. PSMs have the potential to be used as a promising biofertilizers for solubilizing mineral nutrients and increasing its availability for improving plant growth and nutrient absorption other than commonly used conventional methods.