Effect of phosphorus fertilization on nutrient absorption and potato yield in Andisols of Costa Rica

Abstract

The effect of P additions on potato yield and nutrient absorption was studied in a Hydric Hapludands soil. P rates of 0, 150, 300, 450, and 600 kg.ha^-1 of P₂O₅ were compared during 1 and 2 consecutive crops. Soil samples were taken before planting and after harvest; foliar samples were taken, 48 dap at flowering; aerial biomass was sampled before burning aerial biomass with chemicals, 93 dap; potato yield was estimated at harvesting, 116 dap. Tissue samples were analyzed for N, P, Ca, Mg, K, Mn, Zn, Cu, Fe, S, and B. When P was applied only to the first crop, yields were low and no residual effect of the fertilizer application was noted for any of the rates compared. The addition of P for 2 consecutive years increased yields; maximum yield obtained with 600 kg.ha^-1 of P₂O₅ was 16.39 t.ha^-1. Nutrient absorption was not affected by the P applied. Macronutrient absorption was K>>N>>Ca>P=Mg and for micronutrients Fe>>>Zn>Mn>B>>Cu. Mobile nutrients (NPK) were distributed to the tubers in 27-65%; nutrients of relative mobility, such as Cu, Mg, and Zn between 14-38%; less mobile elements (Ca, Mn, and Fe) amounted only 2-6% of the tuber weight. To maximize potato yield in Andisols, P should be applied for each crop, since the residual effect of the P-fertilizer is not enough to supply the needs of the crop in soils with high P retention capacity.