| Orchard canopy structure and physiloogical characteristics of water ecological has important influence on the truit tree colony solar space distribution ,fruit photosynethesis, growth and the quality of yield. 25 years old 'Chang-Fu 2' apples orchard in Shangzhai village, Chaoquan own, Feicheng, Shandong, was choosed and temporal and spatial canopy solar radiation was measured by 3415-LQF5 light quantum meter and WinSCANOPY anlyser, from 2009 to 2010. In order to provide theroetical basis to detemine reasonable amount for the orchard canopy structure adjustment and water management. It was elucidated the tree light using and photosynthesis production potential. Using the CIRAS-Ⅱphotosynthetic analysis system analyzed branches which liveing and in vitro of the photosynthetic rate and transpiration characteristic annual changes in contrast, in order to clarify the changing rule of photosynthesis and water use efficiency and the adjust action of the water potential of leaves for photosynthesis and water use efficifency, it was used for providing theoretical basic for rational water management. In 2009 at the growing season, in shandong agricultural university experiment station, it was studied the 2 years old 'Fuji apple' sapling pot which under the condition of water stress by different moisture gradient in order to clarify the impact of water stress to the 'Fuji apple' sapling. The main results were as follows:(1) A different canopy and different directions of the light distribution and maximum light intensity changes in the availability and changes in solar elevation angle is closely related; different canopy extinction coefficient for the second outer> inner> outer; different seasons of the canopy Light distribution in a single peak curve, in the noon day cycle time to achieve maximum seasonal average canopy light intensity were the spring > summer > autumn; the average growing season canopy light intensity were the outer> times the outer> inner> near the ground; relative light intensity is less than 30% of the natural crown of light intensity with the proportion gradually increased to extend the growing season; year cycle canopy light transmittance rate and leaf area index showed the opposite trend. It was showed that the average Apple different directions canopy light intensity and leaf area index showed a significant negative correlation (r =- 0592 *), and the gap scores were highly significant positive correlation (r = 0.722 **), and average leaf angle was a significant positive correlation (r = 0.647 *). Tree canopy interception of light energy concentrated in the second outer and inner, spring should be the main growth to improve the nutrition of fruit trees, mainly to accelerate the maturity of leaves. Summer and fall should be moderate and reasonable pay more attention to pruning, lower leaf area index, increasing the average distribution of light intensity, improved light utilization efficiency.(2) Fuji apple light saturation point was 1908.3062μmol?.m-2?.s-1, light compensation point 48.3251μmol?.m-2?.s-1, the maximum photosynthetic rate was 22.6427μmol?.m-2?.s-1, dark respiration reaction rate-2.2669μmol?.m-2?.s-1; Fuji apples in Japan, the photosynthetic rate showed a single peak period, one day at 10:00 and reached the maximum, then decreased gradually, with the "midday depression" affect the photosynthetic rate of the main factors that stomatal factors; sufficient water environment can effectively eliminate the "midday depression" to improve the photosynthetic capacity of the tree; Fuji Apple seasonal variation of photosynthetic rate showed a single peak curve, to one year in July maximum; The present study showed that the photosynthetic rate of Fuji apple is transpiration rate, stomatal conductance, temperature and leaf water potential, the result of many factors; Fuji apple in a little pumping of the Leaf, flowering fruit setting period, flower bud differentiation stage, the body of the tree falling leaf water potential, fruit photosynthetic rate, transpiration rate were significantly lower than in vitro shoots, lower leaf water potential to some extent limited the transpiration rate, photosynthetic rate also decreased, a comprehensive analysis of the water use efficiency during the gradual downward trend, it should be carried out in April right to add tree irrigation water. In 6-7 months when the water potential of trees to the maximum, when the moisture stress has increased the photosynthetic rate of the tree, during this period should be given appropriate drought, the tree in August after the water use efficiency, photosynthetic rate and transpiration rate and the difference of isolated smaller branches, taking into account fruit swollen during this period should be given to appropriate irrigation.(3) The photosynthetic rate of Fuji apple leaves presents the single-peak curve under drough condition of PEG simulation ;20% and 40% of the photosynthetic rate under the concentration higher than 60% and 80% concentration of the photosynthetic rate under the condition of value. Concentration gradient of each day from 8:00 to maximum and then began to decline. Under the mild water stress could promote the transpiration rates of the Fuji apple "midday depression".In the conditions of nature continuous forming mositure gradient ,Fuji apple saplings whiche was under proceing study shows that physiological and biochemical characteristics: the first three days in the dry leaf photosynthetic rate increased, decreased over time; time with drought stress, free proline content showed an upward trend; SOD, POD activity, soluble protein content, soluble sugar content first increased and then decreased; MDA content showed a lower early, then gradually increased, in the end of a downward trend.
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