小麦RIL群体苗期抗旱性综合评价

以小麦RIL群体为材料,在水培条件下以PEG-6000模拟干旱胁迫,分析小麦幼苗抗旱相关性状的群体变异,利用主成分分析对抗旱指标进行综合筛选,利用隶属函数值法对供试材料抗旱性进行综合评价,以期为小麦苗期抗旱性状QTL定位及抗旱育种研究提供依据。15个抗旱相关指标主成分分析表明：前6项主成分累计贡献率达82.799%,所代表的6类指标可作为小麦苗期抗旱性鉴定指标,其相对重要性为生物量〉根冠比〉地下部失水率〉最大根长〉相对生长率〉地上部失水率。抗旱综合评价结果表明：父本山农483较母本川35050抗旱性强,群体综合抗旱性有较大的分离变异,111个系抗旱性高于双亲,14个系抗旱性介于双亲之间,5个系抗旱性较双亲低。该群体适于小麦苗期抗旱相关性状QTL定位研究。

Comprehensive Evaluation of Drought Resistance of Wheat RIL Population at Seedling Stage

With a set of recombinant inbred lines(RILs) derived from a cross Chuan 35050 × Shannong 483 as the materials,15 morphological and physiological traits related with drought resistance were analyzed at the seedling stage by hydroponic cultivation with the osmotic stress(OS) treatment induced by PEG-6000.The drought resistance indices were comprehensively screened by the principal components analysis,and the drought resistance of the materials was comprehensively evaluated by the membership function value analysis,which would provide the basis for the QTL mapping analysis and drought resistance breeding.The comprehensive screening results showed that the 6 indices,biomass,root-shoot ratio,root water loss rate,maximum root length,relative growth rate and shoot water loss rate,could be used as the indicators of seedling drought-resistant identification with the accumulative contribution rate of 82.799%.The comprehensive evaluation results showed that the drought resistance of male parent Shannong 483 was higher than that of female parent Chuan 35050.There was great variation separation of the drought resistance among the population.The drought resistance of 111 lines was higher than that of their parents,that of 14 lines was between that of their parents,while that of 5 lines was lower than that of their parents.The RIL population was fit for the QTL mapping analysis for drought resistant traits of wheat at the seedling stage.