青稞和大麦对NaCl胁迫的差异生理响应

Differential Physiological Responses of Hulless Barley and Barley to NaCl Stress

本研究以大麦和青稞为材料,研究了这两种植物在0~2.0%梯度 NaCl 胁迫条件下的种子萌发率、种子苗根和叶相对生长量及耐盐性相关关键内源生理指标的表型特征,为寻找和开发禾本科作物天然强抗逆种质遗传资源建立了必要的实验基础.研究结果表明,NaCl 胁迫条件下,青稞种子的的萌发抑制率显著小于大麦,当 NaCl 浓度为1.0%时,大麦种子萌发抑制率为青稞的2.45倍.在2.0% NaCl 胁迫条件下,青稞幼苗叶片相对生长量可以达到大麦的3.88倍,而种子苗在盐胁迫下根的相对生长量测定结果则显示：青稞根的相对生长量显著高于大麦.植物内源抗逆性相关生理和生化指标测定结果显示：青稞种子苗在 NaCl 胁迫5 d后,叶片组织内源丙二醛含量显著低于大麦,而相同胁迫条件下的细胞内游离脯氨酸（MDA）含量、可溶性糖含量以及超氧化物歧化酶（SOD）比活力等指标则显著高于大麦.这些实验结果证实青稞能够通过增加自身内源通用抗逆途径的效率而表现出比普通大麦显著增强的耐盐性.

In order to mine the genetic resources of traditional cereal crops with strong resistance to abiotic-stress and, the germination inhibition of seeds, the relative growth rate of seedlings＇ roots and leaves and some key physi-ological phenotypes associated with plant salt tolerance were investigated in barley and hulless barley under the salt stress triggered by gradient NaCl concentration varied from 0 to 2.0%. Results showed that the rate of germination inhibition of hulless barley seeds is significantly lower than that of barley under the stress condition triggered by same concentration of NaCl, while the NaCl concentration reached to 1.0%, this value of barley is 2.45 folds higher than that of hulless barley. The relative growth rate of roots of hulless barley seedlings is significantly higher than that of barley under same stress condition, in term of the relative growth rate of seedling leaves, the average data from hulless barley is 3.88 folds of barley. The detection of physiological phenotypes demonstrated that the content of malondialdehyde （MDA） in leaves of barley seedlings is significantly lower in hulless barley, whereas the content of free proline and soluble sugar, as well as the super oxide dismutase （SOD） activity in leaves are significantly lower in barley than that in hulless barley seedlings under the same NaCl stress condition. These results revealed that the hulless barleycould exhibit a significantlyacquired slat tolerance by enhancing the efficiency of intracellular common abiotic-stressresistant pathways, which would be much strongerthanthat in commonbarleyundersalt tress condition.