超级杂交稻两优培九生育后期的光合特性和同化产物的分配

Photosynthetic Characteristic and Assimilate Distribution in Super Hybrid Rice Liangyoupeijiu at Late Growth Stage

以杂交稻组合品种 (以下简称品种 )汕优 6 3和两优培九为材料 ,测定了光合速率 ,PS 光化学活性 ,活性氧代谢 ,1 4 CO2 同化产物分配的指标。结果显示 :在生育后期 ,与汕优 6 3相比 ,两优培九在不同光强下具有较高的光合能力 ;在逆境条件下 ,原初光化学效率 (Fv/Fm)的下降及 O·2 产生速率和 MDA含量增长相对较少 ,表明其具有较强的耐光抑制光氧化能力 ;通过用同位素 1 4 C对光合同化产物运转分配进行研究 ,发现两优培九光合同化产物向穗部的运转速率和分配比率均较高 ,表明其具有较好的源库协调性。

Using hybrid rice cultivars Shanyou63 and Liangyoupeijiu as the experimental materials, photosynthetic rate, PSⅡ photochemical efficiency, the indexes of metabolism of active oxygen and 14CO 2 assimilate distribution were measured. In comparison with Shanyou63 at late development stage, Liangyoupeijiu was of higher photosynthetic capacy under different light intensity, the decrease of primary photochemical efficiency (Fv/Fm) and the increase of O · 2 generation rate and MDA content were relatively less under the stress condition, which demonstrated that Liangyoupeijiu was of tolerance to photoinhibition and photooxidation. Transport rate and distribution ratio of photosynthetic assimilate to ear were all-higher, which indicated that Liangyoupeijiu have better cordination of source-sink in terms of the studies on photosynthetic assimilate using isotope. The above photosynthetic characteristics and assimilate distribution is possibly the physiological basis of superhigh yield in hybrid rice Liangyoupeijiu.