作物学报2012，Vol.38Issue(8)：1452-1459,8.DOI:10.3724/SP.J.1006.2012.01452
散射光和直射光对高粱叶片光合功能的影响
Effects of Diffuse and Direct Light on Photosynthetic Function in Sorghum Leaf
摘要
Abstract
The effects of direct and diffuse light on the leaf-side-specific regulation of photosynthesis were studied in sorghum, a typical C4 plant. Leaf morphology and structure were carefully investigated by semithin cross section of sorghum leaves. Leaf absorption, transmittance and reflectance profiles were similar on the adaxial and abaxial leaf surfaces across the light spectrum from 400 to 800 nm, whether light was illuminated via the adaxial or abaxial surface. The photosynthetic light-response curves showed that the maximal whole photosynthetic rate was higher when the light entered the leaf via the adaxial surface than the abaxial surface. The changing trend of stomatal conductance was similar with photosynthetic light-response curves. However, the maximal photosynthetic rate was much lower when the light entered the leaf via the abaxial surface than adaxial surface when blocking the stomata of light-oriented side by PE membrane. The intensity of direct and diffuse lights varied widely in a day, and that of diffuse light was significantly lower than light compensate point (Ic) of abaxial leaf surfaces in sorghum. Consequently, photosynthetic rate of abaxial leaf surface in sorghum should be mainly droved by self-transmitted light but not diffuse light. Differences in stomatal density, substomatic cavity, contacting areas between bundle sheath and mesophyll cells are related to this feature of abaxial leaf surfaces. The findings of the present study are important for field management, investigation of ecosystem productivity and breeding for high photosynthetic efficiency.关键词
直射光/散射光/结构/光合Key words
Direct light/ Diffuse light/ Leaf structure/ Photosynthesis引用本文复制引用
王晓琳,李志强,姜闯道,石雷,邢全,刘立安..散射光和直射光对高粱叶片光合功能的影响[J].作物学报,2012,38(8):1452-1459,8.基金项目
本研究由国家自然科学基金项目(30871455)和北京市自然科学基金项目(6122025)资助. （30871455）
