Analysis of tree structure and relative light intensity in apple orchard with dwarf interstock for good qualities and high yield in Beijing region

【Objective】The objective of the study was to analyze the tree structure and relative light intensity in apple orchard with dwarf interstock for good qualities and high yield in Beijing region.【Method】 Canopy subarea method was used to study the distribution of the shoots,relative light intensity,yield and quality in the canopy of the 'Tall Spindle' shaped 'Fuji' apple orchard with SH6 dwarf interstock in 2011 and 2012.【Result】The results showed that the average tree height and canopy diameter were 3.32 m and 2.45 m,respectively,while the covering rate was 54.44% and the height to row space ratio was 0.74.The total amount of shoots was 7.83×105 per hectare.The percentage of spur shoots and good spur shoots were 66% and 38%,respectively.In most canopy space,the relative light intensity was above 30%.There was only 4.17% canopy received light lower than 30%.The fruit yield was 79.55 t.hm-2.The mean fruit mass was 299.79g,while the percentage of coloring area and soluble solids content was 97.56% and 14.60%.There was 96.3% fruit with fruit mass above 200 g,which accounted for 97.9% of total fruit yields.【Conclusion】 For higher early yield and better fruit quality,it was key technical measure to increase the covering rate and upper shoot amount in young ‘Fuji’ apple with dwarf interstock in Beijing region.