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With the corn planting density increases, the air and light conditions within the group variation, the group energy utilization. Thus, in the high-density conditions, how to improve the the corn canopy structure, increase air and light conditions within the group to become key maize cultivation. The experiment was done in 2008 to 2009 in the Huang-Huai-Hai area corn technology innovation centers and Crop Biology, State Key Laboratory. To super new varieties of maize Den 701 as test material, in 67500 / hm 2 (D1), density of 90,000 plants / hm 2 (D2) and 112500 / hm ~ 2 (D3) 3 under the conditions, set a spacing configuration (60 60,70 50,80 40,90 30), the research planting density and spacing configuration of super high-yielding corn yield and canopy photosynthetic characteristics. The main findings are as follows: 1 planting density and spacing configuration of plant traits and yield and its components as the density increases, corn production increased number of grains per row and 1000 were significantly lower, and the corn plant strains high and ear height were increased, compared with the density D1, D2 and D3 density of the average plant height increased by 4.9cm and 7.6cm; ear height increased by 9.3cm and 11.4cm. At low density, \Plant height and ear at low density, the spacing configuration was no significant difference in the high-density, \increases. 2 planting density and spacing configuration on dry matter accumulation dynamics of corn dry matter accumulation with the increase of density and high-density \late outstanding. Dry matter accumulation with the density decreases, the high-density and low-density reduced by nearly 1/3 of the amount of dry matter accumulation, mainly in the lower part (150 cm), while the upper difference small. Had a decreasing trend in the lower part of the leaf and stem dry matter accumulation; 210cm leaves dry matter accumulation increases with the density increased slightly. The same density, \3 planting density and spacing configuration corn ear leaf photosynthetic characteristics corn ear leaf chlorophyll content, Pn, Fv / Fm, ΦPS II with the increase of density is decreasing, and are more significant difference in the late growth stage. Photosynthesis key enzyme PEPCase and RuBPCase activity was also found decreasing. Ear leaf photosynthetic capacity with the density reduced. Corn ear leaf chlorophyll content, PN, Fv / Fm, ΦPS II, PEPCase and RuBPCase activity at low density between the spaced configuration there was no significant difference, but in high-density, \significant differences in the late growth stage, appropriate spacing configuration ear leaf photosynthetic capacity. The 4 planting density and spacing configuration photosynthetic characteristics of corn Population Light Distribution groups with the density increases, groups PAR interception rate corresponding increase in the upper interception rate increases, the ear leaf layer and the lower layer interception rate. Three density conditions, the the total interception rate, the ear leaf layer and the lower layer intercepted rate to \. LAI with the planting density increases, but the density maximum LAI at different times, the maximum LAI low density appear in the flowering stage in the filling stage, high-density, and high-density, LAI the decrease with the growth process is greater than low density. At low density, such as the spacing planting LAI highest, high density, \which is conducive to the expansion of the photosynthetic source. After flowering the CAP with density increase canopy photosynthetic rate increased accordingly. The same density, the spacing configuration expressed as \CR after flowering decreased first and then increased. Different growth period showed an increased tendency to increase with the density. The proportion of the total group gross photosynthesis of groups respiration rate (CR / TCAP) increases with the increase of density. The same density, \5 planting density and spacing configuration corn seed setting rate and the upper part of the ear grain endogenous hormone content seed setting rate is decreasing as the density increases. Low density, seed setting rate decreased with increasing spacing; high density, \Density of 90,000 / hm2, \20d ago \These results suggest that, to make corn production has been significantly improved, first, to select a high population density, high-density corn production increased. Second, in the high-density conditions, reasonable spacing configuration, give full play to the corn ontogeny potential, get the coordinated development of the corn groups and individuals, to ensure to increase the yield of corn groups. The combination of high yield and stable yield two factors, the conditions of this experiment, we believe that Den 701 90000 / hm ~ 2 \
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