1Division of Crop & Soil Science, Central Potato Research Institute, Simla-171001, (H. P.).
Direct, residual and cumulative effects of P and K fertilization through organic and inorganic sources on tuber yield and their uptake were studied in the presence of a basal dose of nitrogen on acidic brown hill soils of Fagu (Simla). Tuber size, yield and P & K uptake increased significantly with their application through both the sources. The direct as well as cumulative effect of P and K application was significantly better than their residual effect. FYM had significantly better residual effect than inorganic P and K fertilizer. Application of 30 tons of FYM per hectare was sufficient to meet P and K requirements of potato crop. Application of K alongwith P through inorganic fertilizers was necessary to obtain the optimum tuber yield. Continuous application of lower dose of PK manures was better than the application of double dose in alternate year.
