燕麦种质资源耐盐碱性鉴定评价及耐盐碱种质筛选

Identification and evaluation of salt-alkali tolerance and screening of salt-alkali tolerant germplasm of oat(Avena sativa L.)

受气候变化及人类生产活动影响,世界盐碱地范围不断扩大,土壤盐碱化现已成为限制农业生产发展的重要因素。燕麦是一种耐盐碱性较强的作物,为了评价燕麦种质资源耐盐碱性及筛选耐盐碱的燕麦种质,本研究利用125 mmol L^(-1)NaCl、Na_(2)SO_(4)和NaHCO_(3)(物质的量比为1∶1∶1)的混合盐碱溶液对485份燕麦核心种质材料进行发芽胁迫处理,测定了发芽期发芽势、发芽率、根长、芽长、根鲜重、芽鲜重、根干重和芽干重8项指标,利用相关性分析、主成分分析、隶属函数分析及聚类分析等方法对参试燕麦种质进行了耐盐碱综合评价及筛选。结果表明:盐碱胁迫对测定的8项指标均表现出抑制作用;盐碱胁迫下各指标的隶属函数值之间,及各指标隶属函数值与综合评价值之间均呈现出极显著的正相关性;通过主成分分析将8项测定指标转换成了2个主成分,累计方差贡献率为76.926%;结合隶属函数分析与聚类分析共筛选出2份高耐盐碱型的燕麦材料:燕1606和海阔夫斯基596号,将485份燕麦种质的耐盐碱性划分成了5个等级,其中高耐盐碱材料2份、耐盐碱材料49份、中等耐盐碱材料147份、盐碱敏感材料129份、盐碱极敏感材料158份;综合相关性分析、主成分分析和逐步回归方程结果,确定芽长作为发芽期燕麦耐盐碱筛选的首选指标,其次根鲜重、芽鲜重、发芽势和发芽率也是进行发芽期燕麦耐盐碱综合评价及筛选的重要指标。

Affected by climate change and human production activities,the world’s salt-alkali land is expanding,and soil salinization has become an important factor limiting the development of agricultural production.Oat is a crop with the strong saline-alkali tolerance.To evaluate the salinity tolerance of oat germplasm resources in China,485 accessions were stress treated with 125 mmol L^(-1)NaCl,Na_(2)SO_(4),and NaHCO_(3)(1:1:1 molar concentration)solution at germination stage.Eight growth indexes,including germination potential,germination rate,root length,bud length,root fresh weight,bud fresh weight,root dry weight,and bud dry weight,were identified at the germination stage of oats.A comprehensive evaluation and screening of oat germplasm resources for salt-alkali tolerance was performed by the correlation analysis,principal component analysis,membership function analysis,and cluster analysis.The results showed that salt-alkali inhibited all eight indexes identified,and a significant positive correlation was observed between the affiliation function values of the indexes under salt-alkali tolerance and with the comprehensive evaluation value.Eight evaluation indexes were converted into two comprehensive indexes by principal component analysis,with a cumulative variance contribution of 76.926%.The membership function analysis combined with cluster analysis screened a total of two oat accessions with high salt-alkaline tolerance(Oat 1606 and Heikowski 596)and classified 485 accessions into five classes,including two highly saline-alkaline tolerance,49 salt-alkaline-tolerant accessions,147 medium saline-alkaline tolerance accessions,129 sensitive saline-alkaline accessions,and 158 high saline-alkaline sensitive accessions.The results of correlation analysis,principal component analysis,and stepwise multiple regression analysis,and the bud length was screened as the preferred indicator for the screening of salt-alkali tolerance in germinating oats,followed by root fresh weight,bud fresh weight,germination potential,and germination rate,which were also important indexes for the comprehensive evaluation and screening of salt-alkali tolerance in germinating oats.