Effect of Winter Pruning on Flowering,Shoot-type Composing and Fruiting on Fiji Apple Trees

The effect of different degree of pruning(0,20%,30%,40% and 50%) in winter on growing and fruiting was conducted on 15 year-old Fuji apple trees.The results showed that flower quantity was decreased,but fruit setting rate was increased when pruning degree was increased(0-50%).Cutting 50% total shoots stimulated tree growth more vigorously,percentage of middle and long shoots was increased,but percentage of fruiting shoots decreased.The soluble solids,anthocyanin,and Vc content increased when pruning degree was increased,but titratable acid content in fruit decreased.Fruit clearness index and yield increased firstly and then decreased,and high yield was obtained in the 30% pruning treatments for the two years.Yield fluctuated largely on non-pruning and 50% pruning treatments.So the suitable pruning quality is cutting 30% total shoots,besides,the suitable proportions of long,middle and short shoots is needed.