光照对不同生育期水稻根、叶界面CO2交换的影响

Impacts of Light Quality and Intensity on CO2 Exchange at Root and Leaf of Rice with Different Growth Stages

【目的】探讨光照对不同生育期水稻根、叶界面CO2交换的作用。【方法】试验采用自主设计气态化合物挥发试验装置,在内、外室严密分隔和同步测定的条件下,测定水稻叶际及根际界面CO2的交换速率。【结果】①自然光照下,分蘖期、开花结实期和成熟衰老期日间水稻叶际CO2交换速率分别为-13.58、-10.84和27.36μg/pot·h,水稻叶际是中前期日间CO2重要的汇,同时也是成熟衰老期日间CO2重要的源;夜间水稻叶际CO2排放是中前期水稻植株CO2排放的主要来源;②弱光控试验条件下,不同生育期水稻同步从根、叶界面净排放CO2,但主要以叶际CO2排放为主;在水稻不同生育期,LED黄、绿光有增强水稻叶际CO2排放的明显作用,较强红、蓝光能有效地抑制水稻叶际CO2的挥发。【结论】不同生育期同步增加红、蓝光比例及光强,有降低稻田生态系统CO2排放的作用。

【Objective】The present paper aimed to explore the effect of light on CO 2 exchange at the root and leaf interfaces of rice with different growth stages,【Method】A self-designed gaseous compound volatilization test device was used in the experiment to determine the CO 2 exchange rate at the leaf and rhizosphere interfaces of rice under the conditions of close separation and simultaneous measurement in the inner and outer chambers.【Result】(i)Under natural sunlight,the rice phyllosphere CO 2 exchange rate in the daytime at tillering stage,flowering and seed setting stage and mature aging rice plants was-13.58,-10.84 and 27.36μg/pot·h,respectively.It showed that rice phyllo-sphere was an important CO 2 sink at early-middle rice growth stage,and as well an important source of CO 2 emission at mature aging stage.In early-middle period,CO 2 emissions of the rice plants were mainly from rice phyllosphere at night time.(ii)Under weak illumination,there were a large number of CO 2 emissions from rice phyllosphere and rhizosphere at different rice growth stages,but the main CO 2 emissions mainly came from rice phyllosphere.Compared with LED green and yellow light,CO 2 emissions of rice phyllosphere was inhibited markedly by red and blue light.【Conclusion】In summary,increasing the ratio of red and blue light and light intensity in different growth periods,the effect of reducing CO 2 emissions from rice ecosystems should be reduced.