GROWTH AND YIELD OF WHEAT AS AFFECTED BY PHOSPHATE SOLUBILIZING BACTERIA AND PHOSPHATE FERTILIZER

Abstract

Use of biological alternatives to synthetic fertilizers has radically increased due to the high costs and environmental concerns associated with later ones. Phosphate solubilizing bacteria (PSB) have gained importance as supplements to phosphate (P) fertilizers for eco-friendly crop production. A field experiment was conducted to study the effect of different P fertilizer rates and PSB on the growth and yield of wheat. Treatments comprised of control (without P application), 25, 50 and 75 kg P2O5 ha-1, and inoculation of PSB (Bacillus polymyxa) @ 25 mL kg-1 wheat seed. The experiment was laid-out in randomized complete block design (RCBD) with three replicates. The results showed that application of 75 kg P2O5 ha-1 resulted in maximum plant height (68.29 cm), number of spikelets per spike (18.67) and grain yield (8.51 kg plot-1) and was statistically superior to all other treatments except 50 kg P2O5 ha-1. The highest number of grains per spike (50), yield of main spike (2.49 g), grain yield plant-1 (2.93 g) and 100-grain weight (3.77 g) were also recorded in plots fertilized with 75 kg P2O5 ha-1. Generally, higher bacterial count was observed at 0-15 cm soil depth compared to the lower soil depth (15-30 cm) after three weeks of sowing and at crop harvest. Furthermore, the yield and yield contributing attributes recorded from PSB inoculated plots were statistically identical to those of 25 kg P2O5 ha-1 plots. Hence it can be concluded that PSB inoculation can contribute to wheat yield potential to some extent in resource poor farming system.