The studies were carried out in permanent plots under All India Coordinated Safflower Improvement Project to optimize P requirement of safflower based cropping systems viz., mungbean – safflower at Annigeri (Karnataka), soybean – safflower at Parbhani (Maharashtra) and sorghum (F) – safflower at Arnej (Gujarat). There were 12 treatments comprising application of 100% recommended P to both the crops and reducing P application to 50 or 0% to either of the crops with the other crop receiving 0, 50 or 100% P. When any of the crop in the system received 100% P, the phosphorus solubilizing bacteria (PSB) and farm yard manure (FYM) were included either singly or in combination for the other crop in the system along with 0 or 50% P. The average data for three years indicated that on Typic Chromusterts with high available P, there was no response to P in both crops at Annigeri. However, on clay Chromusterts at Parbhani, it was possible to substitute 100% P needs of either of the crops with FYM without any adverse effect on productivity. On Vertic Ustochrepts at Arnej, application of PSB to both the crops could substitute 50% P needs in both the crops. Further, application of PSB along with FYM could substitute 100% P needs of the crop. The system productivity and net returns also followed a similar trend.
Key words: phosphorus management