UPTAKE OF PHOSPHORUS BY MAIZE PLANT AND AVAILABILITY IN SOIL WITH INOCULATED PGPR FROM ROCK PHOSPHATE

A greenhouse study was conducted to evaluate the effect of inoculating the soil or phosphate rock (PR) with the phosphate solubilizing bacteria (PSB) Citrobacter freundii – J123 on maize (Zea mays L.) growth in a soil of pH 7.8. The study consisted of the following treatments; T1: Control (inoculated), T2: Phosphate solubilizing bacteria (PSB), T3: Phosphate rock @ 2 g kg-1 of soil, and T4: Rock phosphate@ 2 g kg-1 of soil+ Phosphate solubilizing bacteria with five replicates by using complete randomized design (CRD) under pot conditions. The results demonstrated that inoculation significantly (P<0.05) increased the shoot length (14.1%), fresh biomass (31%), straw yield (28.1%), cob diameter (17.2%), 100-grain weight (33.8%), grain yield (36.4%), root dry weight (70.7%), and total P concentration in grain (55.3%) in maize plant as compared to inoculated control treatment. While, analysis of leaves showed a significantly (P<0.05) higher photosynthetic rate, transpiration rate, and total chlorophyll content in comparison to respective control. Post-harvest soil analysis revealed that the integrated use of PGPR containing phosphate solubilizing activity + phosphate rock improved the physicochemical properties of soil. It is concluded that the application of phosphate solubilizing inoculant can successfully be utilized to promote phosphorus nutrition in maize that may lead to improve crop productivity.