| To establish potato fertilizer effect model,“3414”field experiments on potato were conducted in winter fallow rice field of Changde. The results showed that total yield was declined under potassium deficiency; tuber yield, commodity potato rate and total yield were significantly declined under nitrogen and phosphorus deficiency. The fertilizer contribution rate was close to 70% at the present land capability. Nitrogen, phosphorus and potassium had the best yield response in the fertilization level 2 and showed hump-backed pattern as fertilizer amount increasing. The positive effects of fertilizer followed as N ＞ P ＞ K. The tuber total nutrients availability was 22.6%. Nitrogen, phosphorus and potassium content of tuber also had the best yield response in the fertilization level 2 and showed hump-backed pattern as fertilizer amount increasing. The positive effects of tuber nutrients availability followed as N ＞ P ＞ K. Data were analyzed based on the“3414”xperiments to establish the ternary quadratic and one-place quadratic fertilizer models. The recommendation of N, P and K was 15.1, 7.6 and 2.2 kg/667 m2 respectively based on R2 and value to cost ratio (VCR). The optimal ratio of N, P, K was 1:0.50:0.15. |
