The Relationship About Canopycharacteristics Between Yield And Quality On Six Tree Systems Of'cuiguan' Pear

To compare and analyze the production and quality of 'cuiguan' pear,Canopy structure and light distribution of six tree forms including 3 plus 1 form,"A" shape,open heart shape,fence wall form,Y-shaped,Set-up for flat shape was analyzed with LI-6400 device and WinsCanppy2005a device.1.We find that there is signficant relativity among Canopy open degree,leaf area index as well as photosynthetic effective light quantum flux density and there is significant difference among different Canopy tree in different kinds of tree system.2.The result of tree canopy structure analysis shows that the average value of Set-up for flat shape,including Canopy opening,crown reflection,scattering and photosynthetic photon flux density was significantly higher than other 5 kind of the tree forms.However,the average value of leaf area index was opposite.The canopy opening value of Set-up for flat shape was 37.76%,Canopy leaf area index was 1.53 The average angle of canopy leaf inclination was 43.87°,the indensity of Quantum flux of direct light under canopy was 24.579 ?mol·m^-2·s^-1.The Quantum throughout indensity of direct light under canopy was 2.785 ?mol·m^-2·s^-1.The total Quantum throughout indensity of photosynthesis under canopy was 27.358?mol·m^-2·s^-1.3.In the study we found that the canopy photosynthetic characteristics of emerald green crown pear each part of the crown canopy photosynthetic rate change rule for the vertical upper to the lower vertical canopy,Major branch apex to a central base photosynthetic rate reduced in turn.Different tree canopy light distribution inside present a similar change rule.By vertical canopy vertical upper to the lower part of the vertical and horizontal direction from the canopy outside to the inside of the canopy light distribution gradually weakened.4.Light transmission of Set-up for flat shape is the best in the six tree form,Photosynthetic efficiency is 12.35 ?mol·m^-2·s^-1,the canopy of 3 plus 1 form is the highest average photosynthetic efficiency,is 6.99 ?mol·m^-2·s^-1,Per mu yield of 3 plus 1 form is Maximum and the best Fruit quality.The fruit weight,soluble solids,soluble sugar,ratio of sugar to acid physiological index of 3 plus 1 form,"A" shape and Set-up for flat shape is significantly higher than fence wall form,Y-shaped and open heart shape.Titration acid content and stone cell content were opposite.The light utilization rate is higher and fruit weight is uniform.Compared with the typical high yield orchard canopy structure and light characteristics measurement,we found that 3 plus 1 form,"A" shape and Set-up for flat shape is suitable to the pear tree of higher Photosynthetic efficiency in Yangtze River Delta region.