盐和水分胁迫对不同荞麦品种生理特性的影响

以甜荞（平荞2号）和苦荞（黔苦2号）为实验材料，研究NaCl和等渗PEG对荞麦根系活力、质膜透性、MDA含量及净光合速率的影响。低盐度处理时两种荞麦根系活力明显增强，苦荞增加幅度较大，甜荞根部和叶片质膜透性及MDA含量明显增加，苦荞叶片净光合速率明显增加；高盐度处理时两种荞麦根系活力仍保持较高的水平，甜荞根部和叶片质膜透性及MDA含量增加幅度明显大于苦荞，甜荞叶片净光合速率明显下降且下降幅度明显大于等渗PEG处理，而苦荞叶片净光合速率与对照无明显差异。说明质膜透性、MDA含量和净光合速率是荞麦抗逆性敏感生理指标，苦荞的耐胁迫性大于甜荞。

Effect of Salt and Water Stress on Physiological Characters of Different Buckwheat Varieties

Using Fagopyrum esculentum（Pingqiao NO.2）and Fagopyrum tataricum（Qianku NO.2）as experimental materials to study the effect of NaCl and iso-osmotic PEG on roots vigor, plasma membrane permeability, MDA content and net photosynthetic rate of buckwheat. Under lower concentration salt treatment, roots vigor of two buckwheat varieties obviously increased and Fagopyrum tataricum increased more than that of Fagopyrum esculentum. Plasma membrane permeability and MDA content of roots and leaves in Fagopyrum esculentum and net photosynthetic rate of leaves in Fagopyrum tataricum all obviously increased. Under higher concentration salt treatment, roots vigor of two buckwheat varieties also remained high level. Plasma membrane permeability and MDA content of roots and leaves in Fagopyrum esculentum increased obviously more than that in Fagopyrum tataricum. Net photosynthetic rate of leaves in Fagopyrum esculentum under higher concentration salt treatment obviously decreased and decreased more than that under iso-osmotic PEG treatment, while that in Fagopyrum tataricum showed no obviously difference with control. It indicated that plasma membrane permeability, MDA content and net photosynthetic rate were sensitive physiological indexes of stress resistance in buckwheat and the stress resistance of Fagopyrum tataricum was more than that of Fagopyrum esculentum.