用水稻苗期叶绿素含量相对稳定期估算水稻剑叶光合功能期的方法研究

Research on the Method to Estimating Flag Leaf Photosynthesis Function Duration at Rice Seedling Stage by Relative Steady Phase of Chlorophyll Content

用 SPAD- 5 0 2型叶绿素计测定了 8个水稻品种不同叶位连体与离体叶片叶绿素含量的变化 ,结果表明叶片全展后 (或离体后 )叶绿素含量变化可明显划分为相对稳定期和速降期两个阶段。离体与连体叶片、不同叶位叶片间的叶绿素含量相对稳定期均呈极显著线性回归关系。进一步测定其他 34个品种幼苗期离体第 6叶和连体剑叶叶绿素含量相对稳定期并进行若干方程曲线拟合表明 ,用多项式表示两者之间关系的相关系数最大 (r=0 .96 19,P <0 .0 1)。用该拟合方程对另外 10个品种剑叶的光合功能期估算并与实测值之间进行相关分析表明 ,估算值与叶绿素含量相对稳定期和光合速率高值持续期的实测值均达极显著水平 ,其相关系数分别为 0 .9948和 0 .9913(P <0 .0 1)。

Chlorophyll contents in different position intact and detached leaves in eight rice varieties were measured by a SPAD 502 hand held chlorophyll meter. Two periods of chlorophyll content changes in intact and detached leaves, namely relative steady phase(RSP), and rapid declined phase of chlorophyll content, were apparently observed in different rice varieties. Regression analysis results revealed a significant relationship of RSP in detached and in intact leaves and among different position leaves. Furthermore, RSP in the detached sixth and intact flag leaves in other 34 rice varieties were determined and modeled by several equations, showing that the relationship between them expressed in polynomial equation was the best due to its highest correlation coefficient (r=0.9619, P < 0.01). Photosynthetic function durations in flag leaves in the other 10 rice varieties were estimated by this polynomial equation and simultaneously measured in practice. The result showed that estimated value was positively significantly correlated with measured RSP value and active photosynthesis duration, and their correlation coefficients were 0 9948 and 0.9913, respectively, further indicating the relationship between them.