大麦叶片光合速率日变化的初步研究

STUDIES ON THE DIURNAL CHANGES OF PHOTOSYNTHETIC RATE OF BARLEY LEAVES

田间条件下对大麦在不同生育时间和不同光照、湿度、温度条件下叶片光合速率的日变化进行了观测。结果表明,光合速率日变化有时呈单峰曲线,有时呈双峰曲线。光合速率午间下降是由于午间空气温度过高及空气相对湿度过低引起的。

In two growing stages, under the condition of controlling light intensity, temperature, relative humidity respectively or both, the diurnal changes of photosynthettic rate of barlyleaves were studied. The results are that the diurnal changesof photosyntheticrate was a adaptive reflection of the ecological condition. Major ecological factors which caused midday depressing in photosynthetic rrate of barley leaves were low atmospheric humidity and high temperature at midday.