Abstract
Wheat is one of the leading staple crops in many countries. Phosphorus (P) plays an important role for wheat growth and yield as it takes part in many metabolic pathways. Even for soluble phosphatic fertilizers, most of the Pakistani soils, being alkaline and calcareous in nature, show phosphorus use efficiency (PUE) not more than 10-25%. The major issue is the unavailability of P due to fixation and precipitation reactions with soil particles. Composting of rock-phosphate with animal and poultry manures supplied with bio-stimulated phosphate solubilizing bacteria (PSB) not only enhances the RP solubilization but also serves as a potent source of P for plants. Composted/bio-activated rock-phosphate (B-RP), prepared by group of three bacterial strains i.e., Pseudomonas sp. (E11), Bacillus sp. (MN54) and Enterobacter sp. (MN17) aided with molasses (5%) and urea (10%), was tested alone and in various combinations with di-ammonium phosphate (DAP). In this pot trial, the combined application of B-RP and DAP was found superior to the sole application of B-RP. Even the combination of B-RP and DAP sharing equal amount of recommended P showed better results as compared to the sole application of DAP, giving improved shoot biomass (25%), total P-uptake (67%), recovery efficiency of P (75%), dry matter (29%), crude protein (29%), and other yield, physiological and nutritional quality parameters of wheat. So, it could be concluded that integrated use of B-RP and DAP with equal proportion of recommended P could serve as a better management practice for not only improving quantity but also the quality of the wheat grain.