关键词: 单叶蔷薇, 盐胁迫, 外源钙, 种子萌发及幼苗生长

Abstract: In order to explore the alleviating effects of different concentrations of exogenous calcium on the seed germination and seedling growth inhibition of Hulthemia berberifolia under salt stress,the seeds and seedlings of H. berberifolia were used as experimental materials to simulate salt stress with different concentrations of 50,100 and 150 mmol·L^-1 NaCl. The seed germination rate and physiological and biochemical indexes of H. berberifolia seedlings were detected by applying CaCl₂ with different concentrations. The results showed that under salt stress,the germination rate of H. berberifolia seeds,the length of root and stems,F_v/F_m and YⅡ values and photosynthetic pigment content of Hulthemia berberifolia seeds increased significantly after calcium treatment compared with control group. The activities of superoxide dismutase,catalase,peroxidase and other antioxidant enzymes in H. berberifolia seedlings were significantly increased,and the content of H₂O₂ was decreased. In summary,the results of this study clarified the tolerance of H. berberifolia to salt stress,and proved the application of exogenous calcium could alleviate the inhibition of salt stress on the germination of H. berberifolia seeds,improve the germination rate of seeds,and reduce the damage of salt stress on seedlings,and the best relief effect was achieved when the concentration of CaCl₂ was 10 mmol·L^-1. This study can provide scientific basis for the conservation of H. berberifolia resources and the study of associated species of grass plants. This study provided a new direction for alleviating the damage of salt stress on Hulthemia Berberifolia,and provided theoretical support for the conservation of Hulthemia Berberifolia resources.

Key words: Hulthemia berberifolia, Salt stress, Exogenous calcium, Germination, Seedling growth