Abstract:

To study the evolution of wheat traits and genetic diversity in southern Huang-Huai winter wheat region， the wheat varieties in the recent 20 years in southern Huang-Huai winter wheat region were as materials. The evolution of wheat traits and genetic diversity were explored from a new perspective by using Shannon-Wiener diversity index （H\mathrm{\text{'}}） and coefficient of variation analysis， fitting trend line after dimensionless traits， principal component analysis， comprehensive score （D′ value） evaluation， regression model construction and other methods. The indexes used for the evaluation of wheat varieties in southern Huang-Huai winter wheat region and the germplasm with excellent performance were screened. The results showed that a total of 443 wheat varieties were bred in southern Huang-Huai winter wheat region from 2003 to 2022， and it could be divided into 3 stages based on the number of bred varieties： basic stable stage （from 2003 to 2017）， temporary high stage after obvious uplift （from 2018 to 2019）， and blowout eruption stage （from 2020 to present ）. In recent 20 years， plant height of wheat in southern Huang-Huai winter wheat region decreased slowly with time-going； water absorption remained unchanged； spike number， grain number per spike， 1 000-grain weight， yield， basic seedlings， test weight， protein content， wet gluten content and stability time showed upward trend， among which 1 000-grain weight， yield， basic seedlings， test weight and wet gluten content had relatively strong upward trend. The increase of yield was mainly due to the increase of 1 000-grain weight. The proportion of high-quality special wheat （strong gluten wheat， medium strong gluten wheat， weak gluten wheat） increased in recent years， mainly due to the increase in the proportion of medium strong gluten wheat. The proportion of strong gluten wheat has not increased significantly， which was mainly limited by water absorption and stability time. The dispersion degree and evolution trend of agronomic traits and quality traits were quite different， but their genetic diversity was constantly improving with the year，and genetic stability should be further strengthened. The results of regression model construction showed that 5 traits could be used as the evaluation indexes of the comprehensive performance of wheat in southern Huanghuai winter wheat region， including spike number， yield， test weight， protein content and water absorption. Among 443 varieties， ‘Jimai 336’‘Anke 1801’‘Jimai 44’‘Gushenmai 19’ and ‘Huawei 305’， which had higher D\prime， performed well and could be used as excellent germplasm resources in the breeding of strong gluten wheat. In the future， the breeders should strengthen breeding new varieties with high-quality special wheat， especially weak gluten wheat， and enhance the protection and utilization of germplasm resources.

Key words: southern Huang-Huai winter wheat region, wheat （Triticum aestivum L.）, germplasm, trait evolution, principal component analysis, comprehensive evaluation

摘要：

为研究黄淮冬麦区南片小麦种质性状演变，以黄淮冬麦区南片近20年育成的小麦品种为材料，通过Shannon-Wiener多样性指数（H\prime）及变异系数分析、性状无量纲化后拟合趋势线、主成分分析、综合得分（D\prime值）评价、回归模型构建等方法，从新视角探究黄淮冬麦区南片近20年小麦性状及其遗传多样性演变规律，筛选可用于黄淮冬麦区南片小麦品种评价的指标以及表现优异的种质。结果表明，2003—2022年黄淮冬麦区南片共育成443个小麦品种，按育成品种数量可分为3个阶段：基本稳定阶段（2003—2017年）、明显抬升后短暂高企阶段（2018—2019年）、井喷式爆发阶段（2020年至今）。黄淮冬麦区南片近20年小麦育成品种的株高随年份呈缓慢下降趋势；吸水率维持不变；穗数、穗粒数、千粒重、产量、基本苗、容重、蛋白质含量、湿面筋含量、稳定时间呈上升趋势，其中千粒重、产量、基本苗、容重、湿面筋含量上升势头相对较强，产量的增加主要来自于千粒重的提高。优质专用麦（强筋、中强筋、弱筋）占比近些年不断攀升，主要得益于中强筋小麦占比的提升，强筋小麦占比未有明显提升，这主要受限于吸水率和稳定时间。农艺性状和品质性状的离散程度及其演变趋势差异较大，但其遗传多样性均随年份在不断提升，遗传稳定性进一步提高。回归模型结果表明，可将穗数、产量、容重、蛋白质含量、吸水率5个性状作为黄淮冬麦区南片小麦综合表现的评价指标。443个品种中，‘稷麦336’‘安科1801’‘济麦44’‘谷神麦19’‘华伟305’表现优异，综合评价得分较高，在强筋小麦的选育中可作为优异种质资源加以利用。未来应继续加强优质专用小麦新品种尤其是弱筋小麦的选育与引种，加强种质资源的保护利用。

关键词: 黄淮冬麦区南片, 小麦, 种质, 性状演变, 主成分分析, 综合评价