Abstract:

In order to probe into the relationships between the fruit quality and the relative light intensity，as well as the number of branches and leaf in trellis-trained‘Hwangkumbae’ (Pyrus pyrifolia ‘Hwangkumbae’). The method of division in canopy was used to study the distribution of relative light intensity, and shoots and leaves, and fruit quality in different layers and positions of canopy. The results showed that the distribution of relative light intensity in the canopy gradually descended from upper to lower layer, and less 30% of relative light intensity distributed mainly in the lowest layer of canopy. The branches (shoots) and fruitage were distributed mainly from 1.0 m to 2.0 m height of the canopy in uprightness. And the per fruit weight, firmness, soluble solid content were positively correlated to relative light intensity, whereas titratable acidity negatively correlated with it. The regression equations in relationships between quality factors and relative light intensity were set up to obtain optimum relative light intensity 42.17% for per fruit weight, 78.98%for soluble solid, 70.12% for firmness, 59.97% for titratable acidity separately.The regression equations in relationships between relative light intensity and types of branches (shoots) were set up to obtain optimum proportion in shoot, meddle shoot and spur shoot 2.61℅：6.59℅：90.8℅,and total number of the shoots 4.295×105·hm^-2.

Key words: pear, trellis-trained, relative light intensity, fruit quality, branch (shoot)