不同株型水稻品种子粒形成期光合特性的研究

Study on Photosynthetic Characters of Different Spike Types at the Filling Stage of Rice

以不同株型水稻品种为材料,研究了其子粒形成期剑叶与倒二叶的光合能力及其对CO2和光强的适应能力。结果表明:品种之间叶片的光合能力有差异:沈农8718、沈农8714、辽粳454与辽粳294的叶片光合速率均高于其他品种;高气孔导度或高同化能力均可能使品种具有高光合能力。光合速率随外界CO2浓度的增加先增后减,随光强度的增强而上升,且光合能力强的品种(辽粳454)在光强2 000 μmoL/(m2·s)以下未发现有光饱和现象。高光合速率品种具有较低的CO2补偿点(沈农8718为50.54 μmol/mol)和较低的光补偿点(辽粳454为31.40μmol/mol,不同光强及CO2浓度下,气孔导度并不是影响光合作用的主要原因。

Using different spike types of rice varieties as materials, the field experiments on leaf photo-synthetic ability in filling stage were carried out. The results showed that photosynthetic ability of the leaves had no relationship with spike type. The photosynthetic rates of Shennong 8718, Shennong 8714, Liaojing 454 and Liaojing 294 were higher than those of other varieties. Higher stoma conductivity or assimilative ability could make the net photosynthetic rates of varieties higher. Pn increased gradually with the enhancement of CO2 content. Light saturation was not found in Liaojing 454 when light intensity was less than 2 000 μmol/(m2 ·s). The varieties with photosynthetic efficiency had lower CO2(Shennong 8718)50.54 /Limol/mol and lower compensation point (Liaojing 454)31.4 μmol/mol. Pn was not mainly affected by Cs.