Abstract: The purpose of this paper is to elucidate the optimum amounts of nitrogen and potassium in grafted peppers which cultivated in solar-greenhouse,and the difference of them between grafted and the own-root plants. The effects of nitrogen and potassium on the yield of grafted and own-root peppers were investigated with the design of two factors and double saturated D-optimal regression. A mathematical model for the optimization was established using nitrogen and potassium amounts as the independent variables,and the yield of grafted and own-root plants as objective function. The results showed that nitrogen and potassium significantly influenced the yield of grafted and own-root peppers,and there were interactive effect between nitrogen and potassium. However,potassium had higher effect on the yield of pepper. Through simulated computation,the schemes of optimized fertilization of grafted and own-root peppers were finally obtained. The yield of grafted pepper could reach to 49 500 kg/ha or more when the fertilizer rates were N 326.1-752.9 kg/ha,K₂O 630.8-1 116.0 kg/ha;the yield of own-root pepper could reach to 48 000 kg/ha when the fertilizer rates were N 411.5-606.9 kg/ha and K₂O 868.4-1 168.4 kg/ha. The suitable ratio of N:K₂O of grafted pepper was 1:1.96,and that of own-root pepper was 1:1.85.

Key words: Grafted peppers, Nitrogen, Potassium, Yield, Solar-greenhouse

CLC Number: 

• S143.1