Study On The Effects Of The Density, Neighborhood And Combined Effect On The Size Inequality Of Rice

Q You-6 was used for the experiment through comparing 7 treatments to study the rice size hierarchies influenced by density effect,neighborhood effect and combined effect,the results were follows:1 Density effect and combined effect significantly influenced the occurrence of the tiller and panicle,the effect of neighborhood effect was not obvious,this was mainly due to the regulation role of groups which had phototropism and chemotropism;Increasing node leaf area was an important way to increase this node economic production,leaf area and node economic output showed significant exponent regression relationship.2 The average tiller number per plant was different between density effect,neighborhood effect and combined effect.And the chronological order the three effects appeared in was the neighborhood effect,density effect,combined effect.3 Compared with the crops living in semi-arid areas,competition of rice population was not intense,size hierarchies were small,Gini coefficient significantly reduced,which may be related to the biological characteristics of rice and the growth environment of water layer irrigation,so it was reasonable to use the average to represent population characteristics;The measure indicators of size inequality Gini coefficient and the economic output had complex relationship and can not be simply used Gini coefficient to determine the biological production and economic output.4 Sugar content in rice leaves reached highest in the booting stage,and the minimum in mature stage;Percentage of total nitrogen reached the highest in the tillering stage,and then gradually decreased;Starch content was the lowest in the tillering stage,and highest in heading stage,and then gradually decreased.Antioxidant enzymes in the mature stage,as the rice matured, SOD content decreased gradually,MDA content increased gradually,at the same time as the density effect increased,SOD content increased,MDA content had decreased trend;The combined effect increased,SOD content reduced,MDA content increased,neighborhood effect also generally showed the same trend.5 three effects influenced the photosynthesis of flag leaf in flowering stage and milky stage, the combined effect and SOD showed the same trend,but neighborhood effect and density effect showed the less obvious influence on the photosynthesis of flag leaves.In summary,three effects on morphogenesis of rice,physiological indicators,dry matter accumulation and yield formation had a certain impact,thus the decomposition of the three effects had a certain theory.