Nutrient Balance in Relation to High Yield and Good quality of Potato on an Acid Purple Soil in Chongqing, China

摘要

A field experiment was carried out to study nutrient balance among N, P, K and Mg in potato cultivation on an acid purple soil in Chongqing, China. The experiment included 8 treatments with equal P rate of 120 kg P_2O_5 hm~-2: N_oK_2, N_1K_2, N_2K_2, N_3K_2, N_3K_0, N_2K_1, N_2K_1, N_2K_1Mg and N_2K_3, where N_0, N_1, N_2 and N_3 stand for the N rates of 0, 75, 150 and 225 kg N hm~-2, and K_0, K_1, K_2 and K_3 for the K rates of 0, 165, 330 and 495 kg K_O hm~-2, respectively. Among the treatments designed, Treatment N_2K_2 with a nutrient supply ratio of N; P_2O_5:K_2O: MgO = 1.25:1:2.75:0.28 gave the highest tuber yield and dry matter, highest starch and Zn and lowest No~_3 contents in tuber, and high N, P and K use efficiency with an uptake ratio of N: P: K: Mg=11.38:1:13:32:0.33 by tuber.