摘要
以3年生麻疯树为试材,利用Li-6400便携式光合仪系统,测定了自然条件下麻疯树光合生理特性,并分析了各光合生理参数与主要环境因子间的关联性。结果表明:麻疯树净光合速率(Pn)的日变化具有明显的"午休"现象,分别在10:00与16:00左右出现高值,而在14:00前后存在最低值;蒸腾速率(E)的日变化呈早晚低、中午高趋势;气孔导度(Gs)与水分利用率(WU,E)的日变化与Pn基本一致。光合拟合显示,麻疯树最大净光合速率(Pmax)以及光饱和点(LS,P)分别达21.49、1671μmol.m-2.s-1。根据日变化参数Pn、胞间CO2摩尔分数(Ci)和气孔限制值(Ls)的变化方向,推断麻疯树的光合"午休"受气孔和非气孔因素共同限制。相关分析及多元回归分析表明,影响光合作用最重要的因子为Gs,其次为Ls。
An experiment was conducted to study the photosynthetic physiological characteristics of three-year-old Jatropha curcas L. using a Li-6400 portable photosynthesis system （Li-6400,Li-cor USA）. The relationships between photosynthetic physiological parameters and environmental factors were analyzed. The diurnal variation of net photosynthetic rate showed an obvious midday depression,with maximum values occurred at about 10：00am and 16：00pm and a minimum value occurred at 14：00pm. Transpiration rate was lower in the morning and evening hours and higher at noon. The daily variation of stomatal conductance and water use efficiency was consistent with that of net photosynthetic rate. The maximum photosynthetic rate and the light saturation point of J. curcas were 21.49 and 1 671 μmol·m-2·s-1 respectively. The midday depression of J. curcas was controlled both by stomatal and non-stomatal factors judging from the changing tendency of net photosynthetic rate,intercellular CO2 concentration and stomatal limitation. Correlation and regression analyses show that stomatal conductance and stomatal limitation are both important influence factors on the photosynthesis of of J. curcas,but stomatal conductance plays a more important role.
出处
《东北林业大学学报》
CAS
CSCD
北大核心
2010年第7期39-41,70,共4页
Journal of Northeast Forestry University
基金
国家科技支撑计划项目(2007BAD50B004
2006BAD07A04)
关键词
麻疯树
光合日变化
光响应
环境因子
Jatropha curcas
Photosynthetic diurnal change
Photoresponse
Environmental factors
作者简介
陈友根，男，1984年7月生，中国林业科学研究院资源昆虫研究所，硕士研究生。
通信作者：李昆，中国林业科学研究院资源昆虫研究所，研究员。
