谷子叶片光合速率日变化及水分利用效率  

The Diurnal Variations of Photosynthetic Rate and Water Use Efficiency in Setaria italica Leaves

作　　者：廖建雄[1] 王根轩[1] 

机构地区：[1]兰州大学干旱农业生态国家重点实验室,兰州730000

出　　处：《植物生理学报（0257-4829)》1999年第4期362-368,共7页Acta Phytophysiologica Sinica

基　　金：国家自然科学基金

摘　　要：通过降低空气湿度（ 从约３０ ％ 减少到５ ％ ） 、增加ＣＯ２ 浓度（ 从４００ μｌ ＣＯ２／Ｌ增加到７３０ μｌ ＣＯ２／Ｌ） 、烫叶鞘破坏韧皮部等处理对谷子叶片光合速率日变化和水分利用效率（ＷＵＥ） 进行了研究， 发现中午光合速率降低与光合产物积累有关； 虽然低大气相对湿度（５ ％ ） 使光合速率有所降低，但提高了ＷＵＥ。而烫叶鞘使光合物质积累既抑制了光合速率，又降低了ＷＵＥ。Diurnal changes of photosynthetic rate in millet leaves were observed under low relative humidity (about 5%RH), high CO 2 concentration (730 μl CO 2/L) and assimilate accumulation by heat girdling of leaf sheath by CI 301 CO 2 gas analyzer. It was found that the midday depressions of photosynthesis in nature conditions (Fig.1) and low RH(Fig.2) and high CO 2 concentration treatments(Fig.3) were significantly correlated with the accumulation of photosynthates. High CO 2 concentration(730 μl CO 2/L) can increase photosynthetic rate(Fig.4) and decrease transpiration rate(E), so improve water use efficiency(WUE) greatly. Low relative humidity(5%RH) can decrease photosynthetic rate(P n), but improve WUE too, it is why low RH decease stomatal aperture and the E is more dependent on the stomata than P n; assimilate accumulation(heat girdling of leaf sheath) could decrease P n and WUE(Table 1).

关 键 词：谷子 光合午休 水分利用效率 叶片 

分 类 号：Q945.11[生物学—植物学]