氯化钙对盐胁迫下荆芥种子萌发及幼苗生理特性的影响

为研究盐胁迫下，氯化钙浸种对荆芥种子萌发及苗期生理特性的影响，以荆芥种子为试验材料，研究了不同浓度氯化钙（0、2.5、5、10、20、40 mmol·L^-1）浸种后，在150 mmol·L^-1 NaCl胁迫下，荆芥种子的萌发及幼苗生长指标的变化。结果表明，在150 mmol·L^-1 NaCl胁迫下，荆芥种子萌发及幼苗生长受到明显抑制。与单纯盐胁迫处理相比，氯化钙浸种处理后荆芥种子的发芽率、发芽势、发芽指数、活力指数及幼苗的株高、根长、鲜重等均有不同程度提高；荆芥幼苗中超氧化物歧化酶、过氧化物酶和过氧化氢酶的活性提高；幼苗中丙二醛及脯氨酸和可溶性蛋白含量降低。由此表明，氯化钙浸种对NaCl胁迫均具有一定缓解作用，其中20 mmol·L^-1氯化钙浸种对盐胁迫的缓解效果最佳，可显著提高盐胁迫下荆芥幼苗的抗氧化酶活性，缓解膜脂过氧化作用，降低膜系统损伤程度，增强荆芥幼苗的抗盐性，为荆芥在盐渍土地区的栽培生产提供理论依据和技术参考。

Effects of CaCl2 on Seed Germination and Seedling Physiological Characteristics of Schizonepeta tenuifolia Briq. under Salt Stress

In order to study the effects of calcium chloride soaking seeds on the germination and physiological characteristics of Schizonepeta tenuifolia Briq. under salt stress, the seeds were soaked in different concentrations of CaCl₂ (2.5, 5, 10, 20 and 40 mmol·L^-1). The germinations of seed and physiological characteristics of seedling were measured in 150 mmol·L^-1 NaCl solution. The results showed that the seed germination and seedling growth of Schizonepeta tenuifolia Briq. were obviously inhibited under 150 mmol·L^-1 NaCl stress. Compared with salt stress treatment without CaCl2, soaking seeds of CaCl2 could improve the germination rate, germination potential, germination index, vigor index of seeds and the height, root length, fresh weight of seedlings. And the activities of superoxide dismutase, peroxidase and catalase of seedlings were increased, while the contents of malonaldehyde were decreased after CaCl₂ soaking. In addition, the contents of proline and soluble protein of seedlings were decreased after CaCl₂ soaking. These results indicated that CaCl₂ soaking could alleviate the damage under salt stress, and the effect of the treatment with 20 mmol·L-1 CaCl₂ was the best, which provided theoretical basis and technical reference for the cultivation and production of Schizonepeta tenuifolia Briq. in saline land area.