【摘要】 以油菜和诸葛菜幼苗为试材,研究5个光强梯度对其光合电子流传递和叶绿素含量、光合特征、硝酸盐含量、硝酸还原酶活性的影响。结果表明:油菜和诸葛菜的光合电子流传递随光强增加,先缓慢增加后快速上升并达到最大,叶绿素含量、光合速率、硝酸还原酶活性与光强呈正相关,硝酸盐含量与光强呈负相关,诸葛菜和油菜幼苗在光照剂量分别为275和300μmol·s^-1·m^-2时,光合电子流传递快速增加,硝酸还原酶活性快速增强,硝酸盐含量快速下降,存在一个明显的光照强度拐点,在拐点光照强度之后,油菜和诸葛菜光合电子流传递和硝酸盐含量变化不显著。从经济角度来讲,拐点光照强度即为苗期油菜和诸葛菜的最优光照强度。更多还原

【Abstract】 With seedlings of B.napus and O.violaceus as experimental materials,the effects of five light intensity gradients on electron stream transmission,chlorophyll content,photosynthetic characteristics,nitrate content and nitrate reductase activity were studied.The results showed that with light intensity increasing the electron stream transmission,firstly slowly increased,and rapidly rised until reached maximum,photosynthetic rate,chlorophyll content and nitrate reductase activity of B.napus and O.violaceus were positive correlativity to light intensity.The contents of nitrate was negative correlation to light intensity.Analyzed indicators to obtain that 275μmol · s^-1 · m^-2 and 300μmol · s^-1 · m^-2 respectively was the best light intensity of B.napus and O.violaceus.In this light intensity photosynthetic electron stream rapidly increased,nitrate reductase activity increased quickly,the nitrate content decreased rapidly.There was a clear turning point of light intensity,and after this point the changes of photosynthetic electron stream,nitrate content and nitrate content are not notable.更多还原