Effect of different fertilization on yield and quality of Fuji apple

To study effects of different N, P and K fertilization on quality and yield of Fuji apple in order to provide the theoretical foundation for high yield and quality of apple production in the Weibei tableland. A 5 year field experiment from 2004 to 2008 was conducted. The results showed that the apple yields are increased by 12.62% to 48.57% under the different fertilization, and the order of increase rates by the elements is N＞K≥P. The effect of application of N fertilizer combined with P and K fertilizers is the best, the ratio of apple diameters which are bigger than 75 mm is increased from 53.7% in 2004 to 81.2% in 2008, and the ratio of sugar/acid is increased from 37.1 to 39.9. However, for the NP, PK and NK treatments, the ratio of sugar/acid, Vc and hardness are all decreased, especially for the NP treatment, the ratio of sugar/acid and Vc are decreased by 36.3% and 15.6% respectively. Application of N, P combined with K fertilizer can improve the apple yield and quality.