| The canopy developing characteristics of different tree age and shape, temperature distribution conditions in canopies, and light requirement threshold of fruit coloring and quality developing were studied with apple trees of intensive planting on dwarf rootstock the ages of which were three-year-old, six-year-old and mature respectively and mature standard trees of intensive planting. The main research results were as follows:1. The canopy parameter between intensive planting on dwarf rootstock and mature standard trees of intensive planting were no significant differences. As the tree age increased in apple orchard of intensive planting on dwarf rootstocks, there was an obviously decreasing tendency in the Proportion of Visible Sky, Indirect Site Factor, Direct Site Factor and Globle Site Factor respectively, but an increasing tendency in Leaf Area Index. However, these parameters had no significant difference in different trees of the same age.The six-year-old apple tree intensive planting on dwarf rootstock is no significant differences with the intensive planting on dwarf rootstock and mature standard trees of intensive planting.It was mean that skeleton the six-year-old tree was formed.2.The temperature changes of different parts in canopies of intensive planting trees on dwarf rootstocks and the air temperature changes tended to be uniform, which showed that the canopies received uniform light. However, the temperature changes in standard trees of intensive planting lagged behind the air temperature changes. The temperature of the parts with less light was lower than the air temperature out of the crown, which indicated that the temperatures of different parts were inconsistent, because of bigger trees with more leaves and branches.3. The Chlorophyll Fluorescence Fv/Fm of different parts in canopies of dwarf trees were as follows: These both in the lateral eastern side and western side were significantly lower than those in the eastern and central parts, meanwhile, they were also lower than those in other parts but without significant difference, and there were no obvious differences in all other parts. The Chlorophyll Fluorescence Fv/Fm of the parts with less light were significantly lower than those in other parts. There were also no significant differences in those of the parts which received even light.4. The results showed that the anthocyanin in peel of bagged fruits increased rapidly after bag removing of intensive planting on dwarf rootstocks, anthocyanin content in fruit peel removed bags 18d before harvest had a rapid increase during early stage and a slow accumulation close to picking, that of 12d before harvest increased continuously until harvest, but no significant differences of anthocyanin contents were detected in both treatments of removing bag at harvest. The soluble sugar content of different periods of bag removing had no significant effect, but the organic acids of early bag removing are higher than that of late bag removing. The apple fruit coloring needed at least 46.289×106lx solar radiation accumulation from removing bags to harvest in this study.5. As to the fruits on different canopies of both the dwarf trees and standard trees, the titratable acid contents of the fruits receiving less light were significantly higher than those in other parts, and these in other parts showed no significant difference. All the soluble solid contents presented no obvious difference as well.6.In mature orchards of intensive planting on dwarf rootstock, the individual parameters were 3m to 4m tree height, 1.8m to 2.2m crown diameter, 18 to 22 branches of the stem, approximate 0.3 stem tapering, about 2.5 branch diameter to trunk diameter, 0.9m average length of branches, and 1/4 ratio of long shoots to medium and spurs. As to the population parameters, there were 9×105(±15%) branches per hectare with 65%(±15%) coverage and approximate 4.5×104kg fruits , the amplitude yield was less than 20% in alternate bearing. The proportion of long branches , medium and spurs were 19.8%,11.7% and 68.5% separately. Besides, the coefficient of variation between strains was less than 15%.
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