抽穗后水稻根系活力与地上部叶片衰老及净光合速率相关性的研究

Research on the Relationship between the Root Activity and Leaf Ageing,Photosynthetic Rate of Rice after Heading Stage

[目的]为水稻优质高产提供科学依据。[方法]以武运粳8号为材料,采用密肥措施塑造不同产量群体,对水稻抽穗后根系活力和上三叶叶片衰老以及光合速率的变化进行探讨,了解水稻抽穗后根系活力变化对地上部叶片衰老及其光合速率的影响。[结果]水稻抽穗后的根系活力与上三叶中超氧化物歧化酶(SOD)、过氧化物酶(POD)活力及叶绿素含量、叶片净光合速率都存在正相关关系,与丙二醛(MDA)含量呈负相关关系,说明抽穗后根系活力强的群体地上部功能叶衰老缓慢,叶绿素含量下降速度慢,使抽穗后水稻的功能叶捕获光能的能力增强,从而形成较高光合能力的水稻群体,最终形成高产。[结论]保持抽穗后水稻根系活性可以提高植株SOD、POD活性,降低MDA含量,推迟植株衰老过程,提高产量。

[Objective] The scientific basis for good-quality and high-yielding production was provided through the experiment. [Method] Rice variety--Wuyongjing No.8 being taken as experimental material, the variation of root activity, leaf ageing and photosynthetic rate of upper three leaves after heading stage was investigated based on the different planting density and fertilization measure in order to mold the different rice yield population and master the effect of variation of root activity on leaf ageing and photosynthetic rate after heading stage. [Results] The result showed as follows： after heading stage, the relationship of the mot activity with the activity of SOD and POD, the content of chlorophyll and field photosynthetic rate of upper three leaves was positive; with MDA was negative, which suggested that in high mot activity the upper three leaves in the population was ageing slowly after heading stage and the content of chlorophyll decreased slowly, resuhing in the strong ability of upper three leaves in the utilization of light energy, which promoted the rice population with high photosynthesis for high-yielding formation. [Conclusion] The activity of SOD and POD could be promoted, the content of MDA could be reduced and the aging processing could be delayed for the construction of high-yielding rice population based on the vitality mot system after heading stage.