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【Objective】 The present paper aimed to explore the effect of light on CO2 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 CO2 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 CO2 exchange rate in the daytime at tillering stage, flowering and seed setting stage and mature aging rice plants was-13.58,-10.84 and 27.36 μg/pot·h, respectively. It showed that rice phyllosphere was an important CO2 sink at early-middle rice growth stage, and as well an important source of CO2 emission at mature aging stage. In early-middle period, CO2 emissions of the rice plants were mainly from rice phyllosphere at night time.（ii）Under weak illumination, there were a large number of CO2 emissions from rice phyllosphere and rhizosphere at different rice growth stages, but the main CO2 emissions mainly came from rice phyllosphere. Compared with LED green and yellow light, CO2 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 CO2 emissions from rice ecosystems should be reduced. [ABSTRACT FROM AUTHOR]

[Objective]The present paper was conducted to reveal the diversity of rhizosphere microorganisms of marigold and tobacco intercropping system in different growth stages. [Method]The sequences of bacterial 16S-V4 region and the fungal ITS1 region of the rhizosphere samples at the resettling, vigorously growing, squaring and maturation stage were measured using lllumina MiSeq high-throughput sequencing technique, then the sequences of different samples and operational taxonomic units were arranged by stitching with Hash and filtering with Qi-ime for the analysis of diversity of species and difference of distribution. [Result]260 578 effective bacterial sequences and 14 360 OTUs, 189 716 effective fungal sequences and 3288 OTUs were obtained. The Shannon index was the highest at the squaring stage, and interplanting had higher Shannon index than monoculture, indicating that there was a diversity of bacterial species at the squaring stage and intercropping would increase the differences among the bacterial species. For fungi, Shannon index with the intercropping increased first and then decreased eventually, monoculture had the same change trend, and reached the maximum at maturity. [Conclusion] Intercropping significantly reduced the amount of Alcanivorax and Marinobacter at the vigorously growing stage, intercropping increased the amount of Conocybe at the resettling stage while reducing the amount of Microidium at the maturation stage, which changed the composition of fungal community at different growth stages. [ABSTRACT FROM AUTHOR]