Abstract:

Ten kinds of alfalfa seeds were treated with different concentrations of Na₂CO₃, NaHCO₃ mixture to study the effects of salinity-alkalinity stress on the characteristics of seed germination and the growth of seedlings. Results showed that low concentration stress (30 mmol·L^-1) tended to have a promoting effect on seed germination, with the increase of the salt concentration, the seed germination rate, root length, bud length and the vigor index of all the alfalfa varieties showed similar trends, an increased firstly and then decrease. However, the reduction extents were different among different varieties. Used the method of subordinate function, the 10 alfalfa varieties were ranked in an order of strong to weak salinity-alkalinity stress tolerance: ‘WL343HQ’ > ‘WL903HQ’ > ‘Xun lu’ > ‘WL525HQ’ > ‘Zhao dong’ > ‘Sai te’ > ‘Biao gan’ > ‘Jing xi’ > ‘Long mu 801’ > ‘Zhong mu NO.1’.

Key words: Alfalfa, Soda salt and alkali stress, Seed germination, Subordination function method

摘要：

用不同浓度的Na₂CO₃，NaHCO₃混合液对10种紫花苜蓿（Medicago sativa）种子进行盐碱胁迫，研究不同胁迫浓度下种子的萌发特性和芽苗的生长情况，分析盐胁迫对不同苜蓿品种种子萌发的影响。结果显示：低浓度（30 mmol·L^-1）胁迫对种子发芽有促进作用，随着浓度的升高苜蓿种子发芽率、根长、芽长和活力指数呈现先上升后下降的变化趋势，但不同品种降低幅度不同。利用隶属函数法对苜蓿种子的抗盐性进行综合排序，由强到弱依次为：‘WL343HQ’ > ‘WL903HQ’ > ‘驯鹿’ > ‘WL525HQ’ > ‘肇东’ > ‘赛特’ > ‘标杆’ > ‘惊喜’ > ‘龙牧801’ > ‘中苜1号’。

关键词: 苜蓿, 苏打盐碱胁迫, 种子萌发, 隶属函数法