摘要
气孔导度模型是评价植物叶片气孔调节的重要工具。为比较几种常用的气孔导度模型对烟草的适用性,本研究采用Li-6400光合测定系统,测定了大田条件下,烟草叶片在控CO2(390μmol.mol 1)和控温(20℃、25℃、30℃和35℃)情况下的气孔导度光响应曲线。以Ball-Berry模型(BB模型)、Leuning修正模型(BBL模型)、叶子飘和于强推导的机理模型(BBY模型),对各温度下烟草的气孔导度进行拟合和比较,将气孔导度模型与净光合速率的光响应修正模型进行耦合(耦合模型),研究了烟草气孔导度的光响应特征,并与Jarvis模型进行比较。拟合结果表明,较之BB模型和BBL模型,BBY模型能更好地描述各温度下烟草气孔导度与净光合速率之间的关系。耦合模型和Jarvis模型都能较好地拟合烟草气孔导度对光强的响应曲线,但耦合模型的拟合效果更好,且可以直接估算最大气孔导度和对应的饱和光强,同时可以研究最大气孔导度与最大净光合速率是否同步的问题。结果表明,各温度下,烟草最大气孔导度与最大净光合速率并不同步。20℃下气孔导度早于净光合速率达到最大值,而其余温度下气孔导度晚于净光合速率达最大值。
Stomata regulates key plant processes,inluding CO2 assimilation and water use.Although stomatal conductance models evaluate stomatal regulation by plant leaves,model fits have been often different from research and environmental factors.To compare the applicability of stomatal conductance models in tobacco plants,light-response curves of stomatal conductance were measured in this study.The field study was conducted under controlled CO2 concentration and temperature using the Li-6400 photosynthesis determination system.CO2 concentration was maintained at 390 μmol.mol 1 under different temperatures of 20 ℃,25 ℃,30 ℃ and 35 ℃.Stomatal conductance of tobacco across the temperature treatments were fitted with the Ball-Berry model（BB model） and subsequent refinements made by Leuning correction model（BBL model）,as well as a mechanism model deduced by Ye Zipiao and Yu Qiang（BBY model）.The fitting effects eventually compared.The stomatal conductance model and the emendatory light response model of net photosynthesis were coupled（coupling model） to study the light response characteristics of tobacco stomatal conductance.The results were compared with that from Jarvis model.The fitting results showed that compared with the BB and BBL models,the BBY model better described the relationship between stomatal conductance and net photosynthesis of tobacco across the temperature treatments.Both the coupling and Jarvis models well fitted the response of stomatal conductance to light.However,the fitting effects of the coupling model were better,which directly estimated the maximum stomatal conductance along with the corresponding saturation light intensity.Also the coupling model could be used to study the extent of synchronization of maximum stomatal conductance and net photosynthetic rate.The study showed no synchronization of maximum stomatal conductance and maximum net photosynthetic rate of tobacco across the temperature treatments.At 20 ℃,tobacco stomatal conductance reached the maximum value earlier than net photosynthetic rate.At other temperature treatments,however,tobacco stomatal conductance reached the maximum value later than net photosynthetic rate.
出处
《中国生态农业学报》
CAS
CSCD
北大核心
2013年第8期966-972,共7页
Chinese Journal of Eco-Agriculture
基金
国家科技部公益性行业科研专项(GYHY200906021)资助
关键词
烟草
气孔导度
气孔导度模型
光响应
Tobacco
Stomatal conductance
Stomatal conductance model
Light response
