大麦种质资源苗期耐碱性鉴定与综合评价

Identification and Comprehensive Evaluation of Alkaline Tolerance of Barley Germplasm Resources at Seedling Stage

以285份大麦种质资源为材料,在100 mmol·L^(-1)混合碱(Na_(2)CO_(3)∶NaHCO_(3)=1∶1)胁迫下研究了不同大麦种质资源的耐碱性.结果表明,碱胁迫下,苗长、根长、根条数、地上鲜重、地上干重、根干重和根鲜重均受到不同程度的抑制,以对地上鲜重的影响为最大;相对苗长、相对根条数、相对地上鲜重、相对地上干重、相对根干重和相对根鲜重之间呈极显著正相关(P<0.01),存活天数与相对地上鲜重、相对根干重和萎蔫系数呈显著或极显著负相关(P<0.05或P<0.01).通过主成分分析将9个单项性状指标转化为6个综合指标,累积贡献率为87.201%;以6个主成分的得分值计算综合得分值,并通过聚类分析将285个大麦种质划分为4类耐碱类型,其中,耐碱品种13个,中度耐碱品种94个,中度碱敏感型品种90个,碱敏感品种88个.同时,利用回归分析建立了可用于评价大麦耐碱性的回归方程F=0.0436+0.1613X_(1)+0.2234X_(2)+0.1758X_(4)+0.1654X_(5)+0.1907X_(6)+0.1427X_(7)+0.0896X_(8)+0.0831X_(9),相对苗长、相对地上干鲜重、相对根干鲜重、存活天数和萎蔫系数可以作为大麦耐碱性的评价指标.

285 barley germplasms resources were used to study the alkali tolerance of different barley germplasms under 100 mmol·L^(-1) mixed alkali(Na_(2)CO_(3)∶NaHCO_(3)=1∶1).The results showed that seedling length,root length,root number,aboveground fresh weight,aboveground dry weight,root dry weight and root fresh weight were all inhibited in different degrees under alkali stress,and the effect on aboveground fresh weight was the largest.The relative seedling length,relative root number,relative aboveground fresh weight,relative aboveground dry weight,relative root dry weight and relative root fresh weight were significantly positively correlated(P<0.01).There was a significant or extremely significant negative correlation(P<0.05 or P<0.01)between survival days and relative aboveground fresh weight,relative root dry weight and wilting coefficient.The 9 individual trait indexes were transformed into 6 comprehensive indexes by principal component analysis,and the cumulative contribution rate was 87.201%.Comprehensive score for alkaline tolerance was calculated from score of the 6 principal components.The 285 barley germplasms were divided into 4 types of alkali tolerance by cluster analysis,including 13 alkali tolerant varieties,94 moderate alkali tolerant varieties,90 moderate alkali sensitive varieties and 88 alkali sensitive varieties.At the same time,a regression equation F=0.0436+0.1613X_(1)+0.2234X_(2)+0.1758X_(4)+0.1654X_(5)+0.1907X_(6)+0.1427X_(7)+0.0896X_(8)+0.0831X_(9) was established to evaluate the alkaline tolerance of barley.Relative seedling length,relative dry and fresh weight above ground,relative dry and fresh weight of root,survival days and wilting coefficient can be used as evaluation indexes of barley alkali tolerance.