强化栽培条件下水稻不同群体生育后期的根叶特性研究

Studies on Roots and Leaves Characteristics of Different Populations under System of Rice Intensification after Flowering Stage in Hybrid Rice

对杂交水稻组合红莲优6和两优1193在强化栽培条件下不同群体生育后期的根系和光合生理特性进行了比较分析。结果显示,水稻根系密度随着群体增大而增大,但是根系活力却逐渐减小。齐穗后高产群体的剑叶叶绿素日衰减幅度较小,齐穗期剑叶叶绿素含量处理间差异不显著,但成熟期高产群体HMP、LMP的剑叶叶绿素含量分别为2.15、2.87,显著高于HLP和LLP处理,高产群体在齐穗后20d仍然具有较高的剑叶净光合速率。上述结果是高产群体水稻单位面积的产量极显著高于低产群体的主要生理原因。

The root and photosynthesis physiological characteristics of different populations of two hybrid rice Honglianyou 6 and Liangyou 1193 after flowering stage under SRI were studied. Results showed that root density was higher in small population than those of lager population, but converse to the root activity. The chlorophyll contents of flag leaf were not different at flowering stage, but which was significantly higher than that of in low yield population, so the range of reduction per days was small in high yield population. The net photosynthesis rate of flag leaf in high yield population also was significantly higher than that of low yield population in reproductive stage. The yield superiority might result from its enhancement of physical activity of plant favorable to the grain development in reproductive stage