“国光”苹果树两种冠形的光合效率和干物质生产

A STUDY ON THE PHOTOSYNTHETIC EFFICIENCY AND DRY MATTER PRODUCTION OF TWO CROWN-SHAPES OF ''''RAILS'''' APPLE TREES

A comparative study was carried out, 1982~1985, on the crown structure, photosynthetic characteristic, photosynthetic efficiency, production and distribution of dry matter, fruit yield and quality of twochief shapes of crown-two-layer-crown and round-head-crown-by30-year-old 'Ralls'apple trees in the orchard of Changli Fruit-tree Research Institute, Hebei Academy of Agriculture and Forestry Sciences. The result of this study verified that the illumination phase of two-layer-crown was much preferable to the round-head-crown.Its photosynthetic rate, photosynthetic efficiency, total dry matter accumulation of various organs, dry matter accumulation of fruit and average yield per 0.066ha were 25.45% , 12.47%, 15.31%, 50.69%, 19.18% respectively higher than the round-head-crown. And its fruit was of high grade quality and stable yield.The result of this study verified its outstanding capability in raising fruit yield and income when extensively introduced to different apple growing districts in Hebei Province.