小麦RIL群体苗期抗旱性综合评价

程凯　解树斌　蒲艳艳　李斯深

摘 要：以小麦“山农0431×鲁麦21”RIL群体的177个系及其父母本为材料，在水培条件下，用PEG-6000模拟干旱胁迫分析小麦苗期抗旱相关性状的群体变异；利用主成分分析对所测定抗旱指标进行综合筛选，并对材料的抗旱性进行综合评价。通过对14个抗旱相关指标的主成分分析表明：前5项主成分累计贡献率为8215%，所代表的5类指标，可作为小麦苗期抗旱性鉴定指标，其重要性为生物量>根冠比>相对生长率、苗高>失水率>根数、最大根长。抗旱综合评价结果表明：父本鲁麦21的D值为057，较母本山农0431抗旱性强，群体综合抗旱性有较大的分离变异，群体中有90个系的抗旱性低于母本山农0431，有11个系抗旱性高于父本鲁麦21，有57个系抗旱性在两亲本之间。

关键词：小麦；重组自交系；抗旱性；苗期；综合评价

中图分类号：S11+7；S512.1+10.1 文献标识号：A 文章编号：1001-4942（2012）11-0017-05

Comprehensive Evaluation on Drought Resistance of

Wheat RIL Population at Seedling Stage

Cheng Kai1， Xie ShuBin2*， Pu YanYan1， Li SiShen1**

（1. State Key Laboratory of Crop Biology / College of Agronomy， Shandong Agricultural University， Taian 271018， China；

2.Institute of Crop Science， Shandong Academy of Agricultural Sciences， Jinan 250100， China）

Abstract With the recombinant inbred lines （RILs） derived from the cross "Shannong 0431 × Lumai 21" as materials， 14 morphological and physiological traits related with drought resistance were analyzed at the seedling stage under hydroponic cultivation with the osmotic stress treatment induced by PEG-6000. The drought resistance indicators were comprehensively screened by the principal components analysis， and the drought resistance of the materials was comprehensively evaluated by the membership function value analysis. The results showed that five could be used as the indicators for seedling drought resistance identification with the accumulative contribution rate as 82.15%， and the order of their importance was biomass>root-shoot ratio>relative growth rate and seedling height>dehydration rate>root number and the maximum root length. The comprehensive evaluation results indicated that the drought resistance of the male parent Lumai 21 was higher than that of the female parent Shannong 0431. There was a great variation separation of the drought resistance among the RIL population. The drought resistance of 11 lines was higher than that of the parent Lumai 21， 90 lines was lower than the parent Shannong 0431， and 57 lines was between the two parents.

Key words Wheat； Recombinant inbred lines （RILs）； Drought resistance； Seedling stage； Comprehensive evaluation

干旱在我国分布广泛，对农业生产影响非常严重。据统计，我国每年受旱面积已上升到（2 700～3 300）× 104 hm2，成灾面积达到1 200 × 104 hm2[1]。小麦是世界上最重要的粮食作物之一[2，3]，有超过35%的人口以小麦为主食，有70%的小麦播种区域分布在干旱和半干旱地区[4]。选育抗旱性好的小麦品种是降低干旱危害的有效方法[5]。

小麦重组自交系（recombinant inbred line，RIL）群体可在很大程度上消除遗传背景干扰，从而较为准确地反映不同性状间的关系[7]。国内外学者对小麦的抗旱机制进行了深入研究，筛选出了一大批与抗旱性有关的形态和生理指标[8]。如间断干旱试验结果表明，在干旱条件下株高、植株平均绿叶数、叶片干物质等性状均有变化[9]；Landjeva……