水稻植株通气系统与稻田CH4排放相关性研究

水稻植株是稻田甲烷(CH₄)排放的重要通道，90%的CH₄气体由水稻植株通气组织排放到大气中。探讨水稻植株通气组织与水稻CH4排放量之间的相关性，可为水稻栽培和育种实践中减排CH₄提供理论和实践依据。2005年早、晚2季大田试验测定了16个水稻品种CH₄排放量和植株地上部各节间组织1

Correlation between Rice Plant Aerenchyma System and Methane Emission from Paddy Field

Rice plants play a pivotal role in methane emission and more than 90% of CH4 released from a rice field during a growing season can be emitted by rice plant-mediated transport.Studying the relationship between rice plant aerenchyma system and methane emission may provide the theoretical and practical basis for reducing methane emission in the course of rice culturing and breeding practice.In a field experiment during early and late rice seasons in 2005,methane emission amount and 16 quantitative characters of plant internodal tissues above ground were determined using 16 cultivars by sampling with the static chamber and measuring characters with microscope technique.The results were as follows:(1) Methane emission amount of hybrid rice reduced by 29.8% and 6.9% respectively at early and late rice seasons compared to the conventional rice,which was consistent with the results documented by other researches.(2) The plant internodal quantitative characters of early cultivars which were significantly correlated with methane emission differed from those of late cultivars.At the same time,the number of correlative factors among stem internodes was different from each other and that of the third internode was more than others.Among early cultivars,only the ratio of the area of transverse section for leaf sheath to the area of transverse section for the second internode was significantly correlated with methane emission at the 0.01 probability level.As to late rice cultivars,the plant height and five area ratios between the quantitative characters,such as leaf sheath vascular bundles and stem wall transverse section in the first internode,leaf sheath transverse section and that of the third internode,total area of vascular bundles including leaf sheath and stem culm and second internode transverse section,total area of vascular bundles including leaf sheath and stem culm and first internodal stem wall transverse section,stem culm vascular bundles and the third internodal stem transverse section,were significantly correlated with methane emission at the 0.01 probability level.(3) Plant height,the area of vascular bundles and the area of gas chambers for leaf sheath are crucial factors to influence methane emission through plant aerenchyma system.By reducing late rice plant height or adding the area of vascular bundles for the first internode,the aim of reducing methane emission amount and improving rice production may be achieved.