国内外301份小麦品种(系)种子萌发期抗旱性鉴定及评价

Identification and evaluation of drought tolerance of 301 wheatvarieties (lines) at germination stage

以-0.5MPaPEG-6000模拟干旱胁迫环境,对301份冬小麦品种(系)在人工气候箱内进行种子萌发培养,在发芽势、发芽率、发芽指数、根数、根长、苗高和胚芽鞘长度测定的基础上,应用隶属函数、聚类分析和因子分析等方法对小麦种子萌发期抗旱性进行综合评价。结果表明,PEG胁迫下各指标测量值较对照均下降,且各指标之间存在极显著或显著正相关。利用隶属函数法进行抗旱性分析,发现不同小麦品种(系)间表现出较大差异,D值的变幅为0.08~0.95。通过聚类分析,将材料按抗旱性强弱分为5类:藁城8901等8份品种(系)为高度抗旱型,周麦22等29份品种(系)为抗旱型,鲁麦8号等116份品种(系)为中等抗旱型,石4185等83份品种(系)为干旱敏感型,烟农18等65份品种(系)为干旱高度敏感型。主成分分析表明,发芽指数、根长和根数在萌发因子、伸长因子和根部性状因子中的载荷量分别为0.96,0.88和0.91。不同抗旱类型麦区间的分布表明,8份高度抗旱型小麦品种(系)均来自国内,其中5份来自北部冬麦区。综合评价得到萌发期高度抗旱型种质分别是川麦44、皖麦33、藁城8901、CA9719、周8425B、宁冬10、新麦37和CA0958。发芽指数、根长和根数可作为小麦萌发期抗旱性鉴定的可靠指标。北部冬麦区可作为挖掘抗旱关键种质的重点麦区。

In this study, a simulated drought stress environment of -0.5 MPa PEG-6000 was used to germinate and culture the seeds of 301 winter wheat varieties (lines) in the artificial climate chamber during the germination period.The germination potential, germination rate, germination index, root number, root length, seedling height and coleoptile length were measured.The drought tolerance was evaluated by the membership function method, cluster analysis and factor analysis.The relative values of the indexes were significantly and positively correlated with those of the controls.Using membership function method to rank drought tolerance, it was found that there were great differences among wheat varieties, the range of D value was 0.08~0.95.By using cluster analysis, we divided all varieties into 5 groups according to drought tolerance.Eight varieties (lines) such as Gaocheng 8901 were highly drought resistant type;29 varieties (lines) such as Zhoumai 22 were the drought-resistant type;116 varieties (lines) such as Lumai 8 were the medium drought-resistant type;83 varieties (lines) such as Shi 4185 were the drought-sensitive type;65 varieties (lines) such as Yannong 18 were the highly sensitive drought type.The results of principal component analysis showed that the maximum load of germination index, root length and root number were 0.96, 0.88 and 0.91 , respectively.The distribution of different drought tolerant types of wheat regions showed that 8 wheat varieties (lines) with high drought tolerance were all from China.Five of the germplasm were from the northern winter wheat region.The germplasms with high drought tolerance in germinating period were Chuanmai 44, Wanmai 33, Gaocheng 8901, CA9719, Zhou 8425B, Ningdong 10, Xinmai 37 and CA0958.The germinating index, root length and root number can be used as reliable indicators for drought tolerance identification in the germinating stage of wheat, and the northern winter wheat region can be used as a key wheat area to excavate drought-tolerant critical germplasm.