2,3-环氧丙酸钾对水稻叶片和叶绿体熒光特性的影响

Effects of Potassium 2,3-epoxypropionate on Fluorescence Characteristics of Rice Leaves and Chloroplasts

用150ppm的2,3-环氧丙酸钾喷施水稻植株,能明显地提高叶片Fd/Fs的比值和叶绿体的Fv/Fo及Fv/Fm的比值,即提高叶片的潜在光合作用量子转化效率和叶绿体的PSⅡ潜在活性和原初光能转化效率。在Mg^(2+)的存在下,能提高PSⅡ与PSⅠ相对荧光强度的比值;在叶绿体类囊体膜蛋白磷酸化的情况下,能提高PSⅠ与PSⅡ相对荧光强度的比值。表明它具有提高Mg^(2+)和膜蛋白磷酸化对两个光系统之间激发能分配的调节能力。 2,3-环氧丙酸钾对光合作用的影响可能是多方面的,并且在水稻生产上有一定应用前景。

The fluorescence characteristics of leaves and chloroplasts were obviously influenced by spraying rice plants with 150 ppm potassium 2, 3-epoxypropionate （2,3-COPA）.The experimental results indicated that the Fd/Fs ratio of intact leaves and the Fv/Fo as well as Fv/Fm ratios of chloroplasts were enhanced by pretreatment with 2,3-COPA,that is to say,the potential photosynthetic quantum conversion efficiency of a leaf and the potential activity of PhotosystemⅡ（PSⅡ） and the efficiency of primary conversion of light energy of PSⅡ in chloroplasts were enhanced by pretreatment of 2, 3-COPA. In addition, the ratio of relative fluorescence intensities of PSⅡ to PSⅠin the presence of Mg2+ and the ratio of relative fluorescence of intensities of PSⅠto PSⅡ in the case of thylakoid membrane protein phosphorylation were also enhanced by pretreatment with 2,3-COPA,respectively.These results illustrated that the capacity of excitation energy distribution regulated by Mg2+ or the phosphorylation of thylakoid membrane between PSⅡ and PSⅠwas strengthened by 2, 3-COPA. The results further showed that effects of 2,3-COPA on photosynthetic processes may be many-sided and 2, 3-COPA will have some prospects for practical application to rice production.