北方冬麦区小麦抗旱种质资源遗传多样性分析

Genetic Diversity of Common Wheat Germplasm Resources with Drought Resistance in Northern China

遗传多样性分析对于作物资源评价和利用具有重要的意义。本研究以我国北方冬麦区136份小麦抗旱种质资源为材料,分析10个农艺性状及其耐旱指数的相关性,以及抗旱种质的遗传多样性。结果表明:在雨养和灌溉条件下,穗叶距的变异系数最高,分别为42.1%和37.2%,单穗总小穗数的变异系数最低,为6.4%和5.7%;不同水分条件下,植株稳产性主要受单株穗数、有效小穗数及穗下节长的影响;性状耐旱指数的多样性指数在1.95到2.07之间变化,平均值为2.02;根据性状耐旱指数将供试材料分为7个类群,其中第I、第III类群材料表现为对水分条件不敏感,而第II类群材料更适于在干旱条件下种植。材料之间的抗旱性差异可以作为抗旱育种中亲本选配的依据。

Genetic diversity analysis in crops plays an important role in evaluation and utilization of crop germplasm resources.In this study,the genetic diversity of 136 wheat（Triticum aestivum L.）germplasm resources with drought resistance were analyzed based on ten agronomic traits and their drought tolerance index（DTI）in rainfed（drought stress,DS）and well-watered（WW）environments.The results showed that length from flag leaf pulvinus to spike base（LFS）had the largest coefficient of variance（CV）of 42.1% and 37.2% in both DS and WW environments,respectively,while the spikelet per spike（SPS）had the smallest CV of 6.4% and 5.7%.Under different water regimes,spike number per plant（SNP）,effective spikelet per spike（ESPS）and peduncle length（PLE）contributed a lot to the stable grain yield.Genetic diversity indices of DTI were from 1.95 to 2.07,with an average value of 2.02.Based on the DTI of agronomic traits,all accessions could be clustered into seven groups,the first and third groups were not sensitive to the water regimes,and the second group was more suitable for planting in dryland.The diversity message on the drought-tolerant plant material might be helpful for the DT improvement in wheat.