Rock Phosphate and Manures with Phosphorus Solubilizing Bacteria Increases the Growth, Yield and Phosphorus Uptake of Okra (Abelmoschus esculentus)

Phosphorus (P) is one of the most important plant nutrient for increasing soil productivity and sustainable crop production. A pot experiment was conducted to study the effect of seed inoculation by phosphorus solubilizing bacteria (PSB) and organic and mineral P fertilizers on growth, yield and P uptake of okra. Phosphorus was applied at the rate of 90 kg ha-1 in the form of poultry manure (PM); sheep manure (SM) and rock phosphate (RP). Nine treatments were allocated for the experiment having PM, SM and RP alone, organic manures with RP in combination, or a mix of the three with PSB. The result revealed that sole application of SM at three growth stages gave maximum root and shoot growth, which was 75 and 78% more from control respectively. It is concluded that Leaf area (36%), chlorophyll contents (62%), yield (60%) and P uptake (31%) of okra were significantly enhanced by the integrated use of PM+SM+RP+PSB at all growth stages over control. Complementary application of this inoculants with manures and RP most favored okra growth and yield and can be considered as an appropriate substitute for chemical P fertilizer in organic and sustainable agricultural system.