Abstract: Salt tolerance indicators of Italian ryegrass(Lolium multif lourum Lam.) at seedling stage were integrated evaluated in order to identify and utilize the suitable germplasm for alkaline soil.Under salt stress at 0% and 0.2% NaCl,the botanical,physiological,and biochemical indicators of Italian ryegrass were determined and analyzed for salt tolerance comparison.The results show that the average plant height,root length,and underground biomass of 16 varieties at 0.2% NaCl were significantly lesser than those at 0% NaCl(P<0.05),the average aboveground biomass was lower than that at 0% NaCl,and the average tiller no.per plant was slightly more than that at 0% NaCl without significant difference.Soluble sugar contents of 7 varieties at 0.2% NaCl were significantly lower than those at 0% NaCl and relative electrical conductivity rate of 11 varieties were significantly higher than those at 0% NaCl(P<0.05).According to the clustering analysis based on the botanical,physiological,and biochemical indicators,the tested 16 varieties were divided into three groups as 8 varieties were relatively salt tolerant,4 varieties moderately salt tolerant,and 4 varieties relatively susceptive to salt stress.

Key words: Italian ryegrass, Salt tolerance, Biomass yield, Cluster analysis

摘要： 采用盆栽实验,对多花黑麦草(Lolium multif lourum Lam.)苗期盐胁迫的各项耐盐指标进行综合研究评价,为筛选适宜盐碱地种植的多花黑麦草品种提供理论依据。设置0%、0.2%2个NaCl盐浓度水平,系统地测定和分析了16个引进多花黑麦草品种苗期植物学指标和生理生化指标。结果表明:0.2%NaCl处理下16个多花黑麦品种平均植株高度、根长、地下部生物量分别显著低于0%NaCl处理(P<0.05);平均地上部生物量低于0%NaCl处理,平均单株茎蘖数略多于0%NaCl处理,但差异不显著;7个品种的可溶性糖含量显著低于0%NaCl处理,11个品种的相对电导率显著高于0%NaCl处理(P<0.05)。对相关的植物学指标和生理生化指标聚类分析得出,相对耐盐品种8个,中度耐盐品种4个,相对盐敏感品种4个。

关键词: 多花黑麦草, 耐盐性, 生物产量, 聚类分析