基于连续12年国家苦荞区域试验的中国苦荞品种选育现状分析

【目的】分析连续12年国家苦荞品种区域试验参试品种农艺性状以及产量变化,探讨中国苦荞品种改良现状和存在的问题,为未来中国苦荞遗传改良提供依据。【方法】依据气候、地理等环境因素对苦荞性状的影响,按照中国南北方地理划分标准将苦荞区试试点分为北方组和南方组,利用聚类分析、相关性分析和多元回归等方法,分析了2003—2014年共12年间国家苦荞品种区域试验参试品种生育日数、株高、主茎分枝数、主茎节数、单株粒重、千粒重以及产量性状在南北方的变异,并比较北方组和南方组苦荞不同性状间的相关性,以及不同育种单位选育的苦荞品种在南北方的性状差异。【结果】12年间,苦荞北方组和南方组参试品种产量分别增加了21%和32%,年均增幅分别为1.8%和2.6%。来自陕西省、甘肃省、云南省、贵州省、江西省、山西省、四川省、湖南省和重庆市等19家育种单位共提供了42个苦荞品种。其中,云南省5个单位,贵州省4个单位,陕西省3个单位,甘肃省、山西省和四川省各2个单位,江西省、湖南省和重庆市各1个单位。来自云南省、贵州省和陕西省的12家育种单位贡献了59.5%的参试品种,这些省区也是苦荞的主要产区。依据不同省（区）苦荞品种聚类分析,在相对遗传距离为5时,可将北方组和南方组苦荞分别分为4类和3类。北方组中陕西省、湖南省和山西省育成品种被分为一组,甘肃省、贵州省、江西省和云南省育成品种被分为一组,重庆市和四川省的育成品种各自分为一组;南方组中贵州省、江西省、云南省和重庆市育成品种被分为一组,陕西省、甘肃省和山西省育成品种被分为一组,四川省和湖南省育成品种被分为一组。相关性分析表明,北方组苦荞和南方组苦荞的单株粒重和产量显著正相关,在北方组苦荞中,单株粒重和株高呈显著正相关;在南方组苦荞中,单株粒重和产量均与主茎分枝数呈显著正相关,而其他性状之间的相关性在南北组中均有所不同。多元回归分析表明,北方组苦荞的生育日数、主茎分枝数、单株粒重和千粒重共同决定了产量53.0%的变异,南方组苦荞的生育日数、主茎分枝数、主茎节数、单株粒重和千粒重共同决定了产量61.4%的变异。【结论】连续12年国家苦荞区域试验表明,苦荞产量及相关性状的改良取得成效,产量有了一定的提升,生育日数有一定缩短,其他性状变化不大。全部供种单位中,云南省、贵州省和江西省选育的品种较其他省份选育的品种具有更广泛的环境适应性。培育高产、稳产、抗逆的苦荞品种仍然是当前苦荞品种改良的主要目标。提高单株粒重、增加主茎分枝数等性状仍是苦荞品种选育的重要途径。选育高黄酮、易脱壳、抗落粒、抗倒伏、成熟期一致和适于机械化栽培的优质专用品种是苦荞生产亟待解决的关键问题。挖掘新型苦荞种质资源与优异基因,加强分子设计育种等新技术研发与应用,提升苦荞品种改良技术和水平是苦荞品种改良的重要努力方向。

An Examination on Breeding Status Quo of Chinese Tartary Buckwheat Varieties Based on the National Cross-Country Tests of Tartary Buckwheat Varieties in China over 12 Consecutive Years

【Objective】Aimed at analyzing agronomic traits and yield changes of national Tartary buckwheat varieties in regional trials over 12 consecutive years, and discussing improvements and existing problems with Tartary buckwheat varieties in China, so as to provide basis for future genetic improvements in Tartary buckwheat in China.【Method】Depending on influences of environmental factors such as climate and geography on characteristics of Tartary buckwheat and in terms of southern and northern trial groups classified according to the geographical division standards of North and South China, the cluster analysis, correlation analysis and multiple regression were employed to analyze variations of Tartary buckwheat varieties in growing duration, plant height, branch and node numbers of main stem, grain weight per plant, 1000-grains weight and yield in the National Tests of Tartary Buckwheat Varieties of China in 12 years from 2003 to 2014 and that examined correlations between different traits of Tartary buckwheat in the northern and southern trial groups, and traits differences of Tartary buckwheat varieties developed by the different breeding units between the two trial groups.【Result】Over the 12 years in question, the yields of the Tartary buckwheat varieties in the northern and southern trial groups increased by 21% and 32%, with an average annual rate of increase of 1.8% and 2.6%, respectively. There were totally 42 buckwheat varieties developed by 19 breeding units of 9 provinces, Shaanxi, Gansu, Yunnan, Guizhou, Jiangxi, Shanxi, Sichuan, Hunan and Chongqing. Of these breeding units, there were 5 units in Yunnan, 4 units in Guizhou, 3 units in Shaanxi, 2 units in Gansu, Shanxi and in Sichuan, and 1 unit in Jiangxi, Hunan and Chongqing City. The tested varieties developed by twelve breeding units from Yunnan, Guizhou and Shaanxi, three major Tartary buckwheat producers of China, made up 59.5% of all the tested varieties. The cluster analysis of Tartary buckwheat varieties from the different provinces (regions) showed that when the relative genetic distance was 5, the northern and southern trial groups can be divided into 4 and 3 classes, respectively. Of the northern group, the varieties from Shaanxi, Hunan and Shanxi were grouped into one class, the varieties from Gansu, Guizhou, Jiangxi and Yunnan were grouped into one class, and the varieties from Chongqing and Sichuan were grouped into one class; and of the southern trial group, the varieties from Guizhou, Jiangxi, Yunnan and Chongqing were grouped into one class, the varieties from Shaanxi, Gansu and Shanxi were grouped into one class, and the varieties from Sichuan and Hunan were grouped into one class. Correlation analysis showed that there was significantly positive correlations between the plant weights and yields of the northern and southern trial groups; significantly positive correlations between the grain weight per plant and yields of the northern trial group and significantly positive correlations of the grain weights per plant and plant heights with the branch numbers of main stems of the southern trial group; and there were different correlations in the other traits between the north and south trial groups. Multiple regression analysis showed that the growing durations, branch numbers of main stems, grain weights per plant and 1000-grains weights of the Tartary buckwheat varieties of the northern group jointly contributed 53.0% to their yield variation, and the growing durations, branch and node numbers of main stems, grain weights per plant and 1000-grains weights of the Tartary buckwheat varieties in the southern group jointly contributed 61.4% to their yield variation.【Conclusion】The national Tartary buckwheat variety regional tests in 12 years from 2003 to 2014 showed that certain improvements were made in the yield and related traits of Tartary buckwheat varieties in the northern and southern trial groups, with their yields increased to a certain extent and their growing durations shortened, but with their other traits not much changed. Of all the breeding units in question, the varieties developed by the breeding units in Yunnan, Guizhou and Jiangxi had wider environmental adaptabilities than the varieties developed by the other units in the other provinces. It was still the main goal in current Tartary buckwheat variety improvement to develop Tartary buckwheat varieties with high and stably yields, stress resistances and other excellent agronomic traits. Correlation analysis showed that it was an important approach in Tartary buckwheat variety breeding to improve Tartary buckwheat in grain weight per plant and branch numbers of main stems, etc. It was the key problem to develop Tartary buckwheat varieties with high flavonoids, easy hulling, good shattering and lodging resistances and uniform maturities and good suitability for mechanized cultivation for Tartary buckwheat production. Identifying new Tartary buckwheat germplasm resources and excellent genes, strengthening researches and developments and applications of new technologies such as molecular design breeding, and improving Tartary buckwheat variety improvement technologies and levels were the important directions in Tartary buckwheat variety improvement.