盐胁迫对不同秋眠等级紫花苜蓿光合作用的影响

Photosynthesis phased response to salt stress in fall dormancy standard varieties of alfalfa

用0、50、100、150和200 m M Na Cl溶液处理不同秋眠等级紫花苜蓿标准品种Maverick、Archer和CUF101,观察形态特征和盐害级别,测定叶片净光合速率(Pn)、细胞间隙CO2浓度(Ci)和气孔导度(Gs),分析盐胁迫对不同秋眠等级紫花苜蓿光合特性的影响.不同秋眠等级紫花苜蓿植株叶片盐害级别随品种和处理浓度不同而不同,但均随Na Cl浓度的增加和胁迫时间的延长而加大.在较低Na Cl浓度下Maverick、Archer和CUF101光合响应存在着预警阶段-恢复阶段-耗尽阶段,在高Na Cl浓度下,所有的供试品种光合响应直接进入耗尽阶段.

The photosynthetic responses of Maverick, Archer and CUF101 to salinity stress by different NaCl concentrations（0, 50, 100, 150, 200 mM） were studied in this project, observing morphological features and levels of salt injury.The net photosynthetic rate（Pn）, intercellular CO2 concentration （Ci） and stomatal con-ductance（ Gs） were measured using Li-6400 under NaCl stress.with the increase of the NaCl concentration and stress time, the level of salt damage had increased in Maverick, Archer and CUF101, while the level of salt damage was different between the varieties and treatments.The photosynthetic response consisted of alarm phase, phase of resistance or phase of restoration, phase of exhaustion, under 50 and 100 mM NaCl.While the photo-synthetic response had nothing but phase of exhaustion, under 150 and 200 mM NaCl.