| The method of annularity deep-ditch fertilizing was used at early summer to determine the effects of applying fertilizer containing low-nitrogen,high-phosphorus and high-potassium(N∶P∶K=1∶2∶2)on growth,yield and quality of Fuji apple in full-fruit period.The purpose of the trial was to make theory basis for fertilization at early summer in Fuji apple orchard in Weibei Highland. Treatment 1 was the CK with no fertilizer and other treatments were treatment 2(N,P,K=0.25,0.5,0.5 kg/plant),treatment 3(N,P,K=0.5,1.0,1.0 kg/plant),treatment 4(N,P,K=0.75,1.5,1.5 kg/plant) and treatment 5(N,P,K=1.0,2.0,2.0 kg/plant).The results showed that fertilizer application at different rates(amounts) improved obviously leaf quality,hastened stem growth and enhanced net photosynthetic rate.Especially the Pn in treatment 3,4 and 5 were increased by 11.84%、14.69% and 11.75% compared to the CK respectively.By the same token,different treatments can improve the production of individuals obviously,and treatments 3(4 with significant differences compared to the CK,especially treatment 3 achieved the fertility purpose with 39.72 kg of individual plant.At the quality aspect,each treatment can improve the weight of single fruit and the rigidity significantly,soluble sugar content and titratable acidity were also improved at different magnitudes.To conclusion,we proposed that treatment 3 and treatment 4 as the moderate model of fertilizer application should be used in Fuji apple orchard in Weibei Highland at early summer. |