水稻对高低光强适应的品种间差异

The Varietal Difference of Rice Adaptation to High and Low Light Intensity

为阐明水稻对高、低光强的适应性,比较了不同品种光系统和光合酶的活性,结果表明:与不耐高光强的品种相比,适应广幅光强的品种在强光条件下,PSⅡ活性、光合速率下降幅度较小,而PSⅠ、碳酸酐酶(CA)、超氧歧化酶(SOD)活性增加,因此叶片受光氧化伤害较轻。在遮荫条件(1,5自然光)下生长,与不耐荫品种相比,适应广幅光强品种RuBPc活性和光合速率及每株干重下降幅度较小。看来,在强光下具有稳定的PSⅡ活性和低光(遮阴14天)下具有稳定的RuBPc活性可能是一个品种适应广幅光强的一个重要特征。

To elucidate the adaptation of rice variety to high and low light intensity, comparison of photosystems and the activity of photosynthetic enzymes among varieties was made. The results showed that the PS Ⅱ activity and photosynthetic rate reduced slightly, the PS Ⅰ activity, Carbon Anhydrase (CA) and superoxide dismutase (SOD)enhanced significantly in the variety adapting to wide range of light intensity in comparison with those susceptible variety to high intensity. Therefore, less photodamage occurred in their blades. Under shading (1/5) natural light)conditions, the reduced range of the RuBPC activity and photosynthetic rate and dry weight of per plant were narrow in the variety adapting to wide range of light intensity in comparison with those susceptible variety to shading condition. It was indicated that the variety adapting to wide range of light intensity retain stable PS Ⅱ activity under high PFDs and stable RuBPc activity under low PFDs.