6个紫花苜蓿品种的耐盐性研究

研究了6种紫花苜蓿在不同浓度盐土中的发芽率、游离脯氨酸含量和鲜草产量的变化规律。结果表明:不同紫花苜蓿品种(或同一品种)在不同盐浓度下的发芽率、游离脯氨酸含量和鲜草产量存在较大差异;盐浓度在0.40%~0.60%间6个品种的发芽率迅速降低;大部分品种的游离脯氨酸含量在盐浓度0.20%~0.30%和0.50%~0.60%时出现双峰;盐浓度为0.20%时大多数品种的产量最高,当盐浓度大于0.30%时不同品种间产量的差异迅速增大。结论认为:中苜1号的耐盐性最强,新疆大叶、爱乐高和甘农3号次之,陇东和甘农1号的耐盐性较差;0.4%为大多数苜蓿品种的耐盐临界值;研究苜蓿耐盐性时应采用多个指标进行综合评价,指标不同选用的盐浓度亦不同。

The Study on Salt Tolerance of 6 Alfalfa Varieties

Salt tolerance of 6 alfalfa varieties was studied by measuring the germination rate,free proline content and yield under the treatments with the different salt stress.The results showed that the germination rate,free proline content and fresh weight of the studied varieties were significantly different in the different salt concentrations;The germination rate of 6 varieties fell rapidly under the treatments with 0.4%-0.6% NaCl solution,while for most of varieties two peak values of the free proline content could be observed in a salt concentration of 0.2%-0.3% and a salt concentration of 0.5%-0.6% separately.In addition,fresh weight of most varieties was the highest under 0.2% salt stress,and the differences of fresh weight among 6 varieties increased quickly with an increasing of salt concentrations from 0.3% to 0.7%.In conclusion,salt tolerance of Zhongmu No.1 was the best among the studied varieties,and that of Longdong and Gannong No.1 were the worst;On the other hand,a salt concentrations of 0.4% could be the critical point of salt tolerance for most of alfalfa varieties.Furthermore,the salt tolerance of alfalfa varieties should be evaluated by measuring multi-indicaes,and moreover,each of indicaes used should be measured in the appropriate salt stress.