棉花优化栽培的群体光分布动态及光合生产的研究

本文应用二次正交旋转组合设计的方法探讨了密度、氮素、单株留果枝数及缩节安化控对棉花群体内光分布动态及光合生产的影响。结果表明，密度和氮素是影响群体内光强大小及干物重高低的主要因子，７月３１日左右是棉花群体内光强的最低阶段。叶面积系数和基部相对光强有极显著负相关（ｒ＝－０．９６１３），叶面积系数保持在３．５６～３．８２，可使棉株基部光强在蕾铃脱落临界光强之上。相对临界光强为１．９２％～３．８５％。此外，开花后干物质日增量与棉株叶片的净同化率呈极显著正相关（ｒ＝０．９１８７）。

Study on the Population Light Intensity Distributive Dynamics andPhotosynthetic Production Dynamics of Optimal C ul ture in Cotton

The design of the quadratic orthorgonal rotation regression was applied to study ef-fect of four factor including density, nitrogen fertilizer ,fruiting branch number and DPC onthe light intensity distributive dynamics and photosynthetic production. The result showedthat nitrogen and density are main factor controling light intensity and dry matter of cottonpopulation. The lowestphase of light intensity appearred on July 31 or so. There are signifi-cant negative correlation between leaf area and relative light intensity. The light intensity ofbottom plant is above limit of bud and boll abssision when LAI keeps between 3.56 and 3.8the limit of relative light intensity is between l. 92%. Otherwise , there are significant linearpositive correlation between dry matter (g/d)after flowering and NAR of cotton leaf.