玉米不同叶位叶片叶绿素含量与光合强度变化规律的研究

有两个玉米品种,于春、夏两季播种。对玉米植株基部(第3叶)、下部(第7、9叶)、中部(果穗叶)和上部(倒二叶)四个叶位和不同叶龄叶片,进行叶绿素含量和光合强度的测定趋势如下:不同叶位叶片的叶绿素含量和光合强度、果穗叶高于其他叶位。叶绿素含量与光合强度呈下相关,不同叶位叶龄大小与叶绿素含量和光合强度的关系,基部叶片充分展开后二者均高。随着叶龄增大而下降:中部和上部叶片充分展开后,随叶龄增大二者增强,至灌浆、乳熟期二值达到最高,以后随着叶龄衰老又逐渐下降

STUDIES ON THE RELATION BETWEEN CHLOROPHYLL CONTENT AND PHOTOSYNTHETIC RATE OF LEAF BLADES ON DIFFERENT NODES IN MAIZE

The content of chlorophyll and photosynthetic rate of leaf blades on the basal, lower. middle and upper nodes and with different leaf age of two maize (Zea mays L.) varieties were measured. Some tendencies were evident. The content of chlorophyll and the photosynthetic rate in the ear leaf on the middle node were higher than those of other leaves. The photosynthetic rate was positively correlated with the chlorophyll (a b) content.The chlorophyll content and the photosynthetic rate of three leaf blades at different age varied. Both were higher after the basal leaf fully expanded, but decreased gradually as the plant grew. Both were increased gradually after the middle and upper leaves fully expanded, and got highest at grain filling stage, and then gradually declined with leaf senescence.