Comparative Performance of Indigenous Rockphosphates and Superphosphate in a Forage-Legume Cropping Pattern

Fertilizer value of different rockphosphates was compared for two years in a forage cropping sequence involving berseem-guar-cowpea under field condition. Phosphates were applied to berseem only each year while guar and cowpea were grown on the residual soit-P. Udaipur, Mussoorie and Laccadive phosphates respectively was 60, 66 and 67% as effective as superphosphate, and the corresponding availability coefficient ratio was 0.50, 0.59 and 0.71. Phosphate application at 60, 120 and 180 kg P₂O₅/ha resulted in an additional production of 16, 9 and 7 quintals of green fodder/kg P₂O₅, respectively.