红千层叶片光合速率和叶绿素荧光参数日变化  

Diurnal Changes of Photosynthetic Rate and Cholorophyll Fluorescence Parameters in Callistemon viminalis DC

作　　者：刘建福[1] 

机构地区：[1]华侨大学生物工程系,福建泉州362021

出　　处：《西南大学学报（自然科学版）》2007年第5期95-100,共6页Journal of Southwest University(Natural Science Edition)

基　　金：华侨大学科研基金资助项目(03HZR1)

摘　　要：以柳枝红千层为材料,研究其在不同天气条件下叶绿素荧光动力学参数和净光合速率的日变化及其与光合有效辐射、温度、空气相对湿度、蒸腾速率等环境因子的关系.结果表明:晴天红千层净光合速率日变化呈不对称的双峰曲线,有明显的“午休”现象;第1个峰值出现在9∶00时,净光合速率达到4·12μmol/(m2·s),第2个峰值出现在14∶00时,净光合速率达到2·84μmol/(m2·s);而阴天净光合速率日变化呈不对称的单峰曲线,波峰出现在11∶00时,峰值为2·42μmol/(m2·s).晴天PSⅡ原初光能转换效率(Fv/Fm)和PSⅡ潜在活性(Fv/Fo)均表现出随着光强增加而逐渐降低;说明光合机构受到部分损伤,PSⅡ原初光能转换效率逐渐下降.而阴天Fv/Fm和Fv/Fo均表现出先下降后上升的趋势,光合活性受到暂时抑制,光合器官并没有受到损伤.影响光合作用的主导环境因子为光合有效辐射、气孔导度和空气相对湿度.The kinetic parameters of cholorphyll fluorescence and the photosynthetic rate of Callistemon virninalis DC were studied under different weather conditions and their influencing factors （photosynthetically active radiation （PAR）, temperature, air humidity and transpiration rate） were investigated. The diurnal variation of net photosynthetic rate in the leaves presented a bimodal distribution and an obvious midday depression occurred in sunny days. The first peak, occurring at about 9：00 a.m.,was higher, with a net photosynthetic rate of 4.12 μmol/（m^2·s）,and the second peak occurred at about 14：00 pm, with a net photosynthetic rate of 2.84 μmol/（m^2·s）.In cloudy days, however, it presented a one-peak pattern.The peak value occurred at about 11：00 am,the net photosynthetic rate being 2.42μmol/（m2·s）.The primary light energy conversion of PS Ⅱ （Photosystem Ⅱ） （Fv/Fm） and potential activities of PS Ⅱ（Fv/Fo） decreased with increasing PAR in sunny days, indicating a damage in PS Ⅱ. In cloudy days, in contrast, the values of Fv/Fm and Fv/Fo decreased first, followed by increase, suggesting that photosynthetic activities were only temporarily inhibited and photosynthetic organs had not been damaged. PAR, air temperature and stomatal conductance were shown to be major environmental factors influencing diurnal changes of net photosynthetic rate.

关 键 词：红千层 净光合速率 叶绿素荧光 光系统Ⅱ 日变化 

分 类 号：S685[农业科学—观赏园艺]