苜蓿和扁蓿豆萌发期耐盐指标筛选及耐盐性综合评价

为探究苜蓿(Medicago sativa L.)和扁蓿豆(Medicago ruthenica(L.)Trautv.)种子萌发期的耐盐性强弱,采用复盐溶液模拟盐胁迫的方法,研究了不同浓度梯度(0.3%、0.6%、0.9%、1.2%、1.5%)盐胁迫对5份野生苜蓿和5份野生扁蓿豆种子萌发的影响。测定了发芽率、发芽势、发芽指数、活力指数、根长、苗长、幼苗干重,利用方差分析、相关分析、主成分分析、隶属函数分析和灰色关联分析进行了耐盐性综合评价。结果表明相同指标不同浓度盐溶液和不同材料之间多存在显著差异,各指标之间存在不同程度的相关关系。各指标中与耐盐强弱最相关的指标为幼苗干重,其关联度为0.752,其次为发芽率,关联度为0.745。供试10份材料中来源于中国内蒙古通辽市大青沟自然保护区的扁蓿豆和中国内蒙古呼和浩特武川县的扁蓿豆耐盐性较强,其综合耐盐D值和关联度均较高,分别为0.807、0.699和0.793、0.716。总体比较供试苜蓿和扁蓿豆材料,扁蓿豆萌发期耐盐性较强。

Evaluation of salt tolerance and screening for salt tolerant accessions of Medicago sativa and Medicago ruthenica at germination stage

The objective of this study was to investigate the salt tolerance between Medicago sativa L.and Medicago ruthenica (L.)Trautv.Five wild alfalfa and five wild ruthenian medic from different areas were selected as test materials.Compared to the control,the salt stress of 0.3％,0.6％,0.9％,1.2％,1.5％ was used to explore the effect of tested materials at germination stage.The comprehensive evaluation index of salt tolerant coefficients containing the germination rate,germination energy,germination index,vital index,root length,seedling length and seedling dry weight were tested.The salt-tolerance comprehensive evaluation value were analyzed by variance analysis,correlation analysis,principal components analysis and subordinate function analysis.The results showed that different salt concentration and different materials had significant differences in the same index.There were different correlational relationships among different indexes.Two indexes including GR and DW were closely related to the salt tolerance,the correlation value was 0.745 and 0.752.Besides,the materials of ruthenian medic came from Tongliao Daqinggou Nature Reserve and Wuchuan county near Hohhot of Inner Mongolia had the higher salt resistance,the D value and the correlation value was 0.807,0.699 and 0.793,0.716 respectively.To sum up,ruthenian medic were better than alfalfa in terms of salt resistance.