Growth parameters, nutrient uptake and soil fertility under wheat (Triticum aestivum) as influenced by levels of phosphorus and phosphate solubilizing micro organisms

Abstract

A field experiment was conducted during the winter season of 1998 99 and 1999 2000, to study the effect of phosphorus levels and phosphate solubilizing micro organisms on growth parameters, nutrient uptake and soil fer tility under wheat (Trticum aestivum L. emend. Fiori Paol.) crop. The treatments consisted of 4 levels of phospho rhs (0, 30, 60 and 90 kg P,O,/ha) and of phosphate solubilizing micro organisms (no inoculation, Pseudomonas striata, Aspergillus awamori and Pseudomonas striata Aspergillus awamori). The growth parameters like dry matter production, root dry weight yield and nitrogen and phosphorus uptake were significantly improved with ap plication of 60 kg P,O ha. Similarly, all these parameters were significantly increased owing to combined inocula tion with Pseudomonas striata Aspergillus awamori over individual and no inoculation. Nitrogen and phosphorus uptake of wheat crop increased significantly only up to 60 kg P,O ha. Though increasing levels of phosphorus (up to 90 kglha) left the soil rich significantly in respect of post harvest status of phosphorus. However, successive higher levels of phosphorus declined the available soil nitrogen status, though significant depletion was observed only up to 60 kg P,O,/ha. Inoculation with phosphate solubilizing micro organisms also reduced the post harvest status of available soil nitrogen and phosphorus pool. Highest deciine was observed due to combined inoculation with Pseudomonas striata Aspergillus awamori. Key words :Wheat, Nitrogen, Phosphorus, Growth parameters