Effects of Row Spacing on Assimilation Production and Grain Yield of Heavy-ear Wheat Lankao Aizao 8

Field plot experiments were carried out to examine the effects of row spacing on photosynthetic production of flag leaves and grain yield in heavy-ear wheat Lankao Aizao8 on the farm of Henan Agricultural University during 2006-2007.The results showed that chlorophyll content,photosynthesis rate,soluble sugar content and sucrose content in flag leaves increased in earlier filling stage with irrigation times increasing,and decreased in later filling stage.The effects of row spacing on chlorophyll content and photosynthesis rate of flag leaves was 15 cm 10 cm 20 cm 25 cm with stronger photosynthetic capability of narrower row spacing.The soluble sugar content of flag leaves in narrower row spacing of 10 cm and 15 cm was higher than that in wider row spacing of 20 cm and 25 cm during anthesis and 28 days after anthesis,and reverse in 35 days after anthesis,it revealed that narrower row spacing maintained stronger flow activity and rapid translocation of assimilating matter in leaves,and stronger supplying ability of assimilating matter in late filling stage.The influences of row spacing on sucrose content of flag leaves was the same as photosynthesis rate with highest of 15 cm row spacing,which reveales that 15 cm row spacing enhance distribution and translation of photosynthesic matter to sucrose,accelerate transportation of reserve carbohydrate of leaves to grain.Reducing 20 cm of row spacing to 15 cm increased significantly ear numbers and grain yield,harmonize yield structures.