Abstract: On the basis of experiments carried out in 1976-1986, the relationship between the light distribution in canopy of thin planting adult apple trees and their yield and quality was found out and as a theoretical basis can be used to improve tree form. It is proposed that double layer delaied open-centred form is a better one to improve the canopy of thin planting apple trees. A proper index of leaving fruit for big and medial size was put forward, a small group of shoot was used as a thinning unit in order to make operators master easy. It is clear that the high yield orchard producing 2.5-3.0 thousand kg per mn requires the level of manurial application and fertility of soil. The circular trench manuring which used widely in production was replaced by one side-alternated trench manuring. Labour forces were saved and injury of roots was reduced and the growth of root system was promoted by using this method. The measure for pruning was developed according to the vigour of apple tree in the paper.

Key words: Apple, Pruning, Thinning, Application of fertilizer, Tree form