【作者】 李聪晓；

【导师】 高志奎； 徐践；

【作者基本信息】 河北农业大学 ， 蔬菜学， 2003， 硕士

【摘要】 本试验以玉竹（Polygonatum odoratum （Mill） Druce var Pkuriflokum （Miq） Ohwi）为试验材料，研究其光合作用日变化特性、气孔运动特性及变化规律。其中光合特性的测定主要采用美国产的CI-301PS便携式光合测定仪进行野外测定：气孔特性采用扫描电镜进行观察。结果表明：在野生环境条件下，玉竹净光合速率日变化曲线在年生长季的各个月份均为单峰型变化曲线，且在6，7，8三个月玉竹的净光合速率明显高于其它月份；遮光和恒温不能改变其净光合速率日变化曲线的类型。表观量子效率的日变化在玉竹整个生长季中均呈早晚高、中午低的规律。与此同时，在恒定温度的条件下，玉竹表观量子效率在一天中保持恒定，不出现自然条件下表观量子效率中午下降的现象；玉竹光补偿点呈单峰型日变化曲线，最高点出现于光照强度较大的14：00前后；土壤及植株水分状况的改变，只对植株叶片水势产生较大的影响，对净光合速率及气孔阻力的大小和日变化规律无明显作用：高浓度CO₂可以促进玉竹光合作用的进程，使玉竹净光合速率在午后仍可在一定时间内维持在一个相对较高的水平，而不出现快速下降的趋势；植株体内光合产物的积累在一定范围内可促进净光合速率增加，当光合产物积累达到一定数量之后，便会对光合作用产生一定的抑制作用，但是光合产物的积累对玉竹净光合速率日变化曲线的类型不产生影响；玉竹叶片气孔在白天为不均匀开闭，大部分气孔的相对开度在0.2～0.5之间，气孔相对开度与蒸腾速率、净光合速率、气孔导度间均呈极显著的对数相关关系，同时在环境条件一定的前提下，不同开度气孔下腔的CO₂浓度亦不相同，且两者间呈对数相关关系。更多还原

【Abstract】 Diurnal change characteristic of photosynthesis and stomatal movement of polygonatwn odoratum were studied in this experiment The photosynthesis characteristics were measured by CI-301PS photosynthesis measure system. Stomatal characteristics was studied by electronic microscope. The results were indicated that the diurnal curve of net photosynthetic rate for polygonatwn adoration was a single-peaked pattern in whild condition, and net photosynthetic rate in June, July and August were higher than the other Months. Shading and fixed temperature can not affect diurnal curve pattern of net photosynthetic rate for polygonatwn odoratum. CO₂ compensation point changes as a single-peaked and apparent quantum yield changes on the opposite direction, but quanta apparent quantum yield keep eternally under fixed temperature. Different water condition of soil and plant make no effect on diurnal pattern of net photosynthetic rate and stomata resistance of polygonatwn odoratum, but can change it’s leaf water potential. High CO₂ concentration can promote photosynthesis, make it keep a high net photosynthetic rate in the afternoon. Small amount of photosynthesis production can promote the improve of net photosynthetic rate, but large quantity of photosynthesis production of can prevent it’s improvement, however the photosynthesis production can not change the form of diurnal pattern of net photosynthetic rate. Stomatal aperture of polygonatwn adoration was non-uniform closure in the day, most of the stomatal’s aperture between 0.2-0.5 Stomatal aperture was greatly related to net photosynthetic rate, transpiration rate and stomatal conductance. The intercellular CO2 concentration was not the same under different stomatal, and they are related greatly by a logarithm equation.更多还原