5种胡枝子光合作用特性及影响因子分析

Analyzing of photosynthetic characteristics and influencing factors of 5 Lespedeza species

自然条件下,对5种胡枝子属植物光合作用日进程和光响应进行了观测,结果表明5种胡枝子净光合速率的日变化在夏季表现为双峰曲线,有光合"午休"现象。牛枝子、达乌里胡枝子、阴山胡枝子、截叶胡枝子和尖叶胡枝子日平均光合速率分别为3.75μmol CO2.m-2.s-1、3.55μmol CO2.m-2.s-1、3.37μmolCO2.m-2.s-1、4.45μmol CO2.m-2.s-1、3.78μmol CO2.m-2.s-1;光补偿点分别为38.23μmol.m-2.s-1、43.24μmol.m-2.s-1、13.75μmol.m-2.s-1、36.11μmol.m-2.s-1和45.46μmol.m-2.s-1;光饱和点分别为:1225μmol.m-2.s-1、1262.6μmol.m-2.s-1、1287.5μmol.m-2.s-1、1462.5μmol.m-2.s-1和1312.5μmol.m-2.s-1显示了阳生植物特性。表观量子效率分别为0.034、0.037、0.32、0.036和0.033,可看出5种胡枝子叶片光能转化效率低,其对光的响应敏感性较差。因此,这5种胡枝子对光环境适应能力强,适合在较大范围栽植。

We measured the diurnal photosynthetic variation and light response curve of 5 plants of LespedezaMichx in natural conditions, and the results showed that the diurnal variation of net photosynthetic rate registered as double - peak curve in summer and had ＂noon break＂ phenomenon in these 5 plants. The mean diurnal pho-tosynthetic rates were3.75μmol CO2·m^-2·s^-1、3.55μmol CO2·m^-2·s^-1、3.37μmol CO2·m^-2·s^-1、4.45μmol CO2·m^-2·s^-1 and 3.78μmol CO2·m^-2·s^-1;And the LSP were 1225μmol CO2·m^-2·s^-1、1262.6μmol CO2·m^-2·s^-1、1287.5μmol CO2·m^-2·s^-1、1462.5μmol CO2·m^-2·s^-1 and 1312.5μmol CO2·m^-2·s^-1 in L.cuneata, L. daurica, L. juncea, L. potaninii and L. inschanica respectively. These 5 plants all manifested the characteristics of helioohile. Based on the quantum efficiencies of 0.034, 0. 037, 0.32, 0. 036 and 0. 033 inleaf surface of them respectively, we founded that the rate of energy conversion is low, and they are not sensitive to light. We can concluded that the adaptation to light of these 5 plants are very strong, and they are all adapted to be planted widely in large areas.