Nitrogen, phosphorus and potassium accumulation and partitioning by the potato group Andigenum in Colombia

Accumulation curves for nitrogen (N-accum), phosphorus (P-accum), and potassium (K-accum) obtained from total dry biomass (W) can be employed for the prognosis of potato production in the Andean region, along with analysis of nutrient partitioning derived from the nutrient harvest index (NHI, PHI, KHI). This research established accumulation curves and translocation curves for N, P, and K using allometric relationships in the potato cultivars Diacol Capiro and Pastusa Suprema (Solanum tuberosum, group Andigenum), cultivated in soils with high and low fertility. The best fit of the accumulation model was obtained with the low fertility soils for the Suprema (N-accum=68.13W(0.504), P-accum=6.724W(0.779), and K-accum=63.93W(0.776)), which expressed the highest production potential and high values of NHI (0.55-0.69), PHI (0.75-0.8) and KHI (0.62). The Capiro' was better adapted to the changes in soil fertility than the Suprema since the models for nutrient accumulation in the Capiro' were significant for both levels of soil fertility. The efficiency of N, P, and K translocation into tubers followed a positive logarithmic model, which showed differences in favor of the Capiro' in the translocation efficiency of mineral nutrients. The accumulation of N, P, and K was established per cultivar and per phenological stage of growth, with up to 33% more P extracted by tubers in the Capiro' than in the Suprema and a comparable extraction of N and K by tubers in both cultivars.