采取混合取样策略,利用荧光SSR技术对来源于我国7个省(自治区)的90份糯玉米地方品种和6个标准测验种自交系基因组的31个简单序列重复(SSR)位点进行了分析。在90个糯玉米地方品种中,共检测出216个等位变异,每个位点检测出2~12个,平均6.9...采取混合取样策略,利用荧光SSR技术对来源于我国7个省(自治区)的90份糯玉米地方品种和6个标准测验种自交系基因组的31个简单序列重复(SSR)位点进行了分析。在90个糯玉米地方品种中,共检测出216个等位变异,每个位点检测出2~12个,平均6.97个,多态性信息量(PIC,polymorphic information content)为0.67,标记指数(MI,marker index)为4.92。可初步将90份糯玉米地方品种划为3个类群,其中,广西和贵州的糯玉米地方品种的遗传多样性相对更丰富。展开更多
The inference of genome ancestry and the estimation of molecular relatedness are of great importance for breeding efficiency and association studies. Seventy SSR loci, evenly distributed in 10 chromosomes, were assaye...The inference of genome ancestry and the estimation of molecular relatedness are of great importance for breeding efficiency and association studies. Seventy SSR loci, evenly distributed in 10 chromosomes, were assayed for polymorphism among 187 commonly used maize (Zea mays L.) inbreds which represent the genetic diversity in China. The identified 290 alleles served as raw data for estimating population structure using the coalescent linked loci, based on the ADMIXTURE model. Population number, K, has been inferred to be between five and seven. Specifying five subpopulations (K = 5) led to a distinct decrease and specifying K to be greater than six resulted in only minimal increases in the likelihood value. Therefore, population number, K, has been inferred into six subpopulations, which are PA, BSSS (includes Reid), PB, Lan (Lancaster Sure Crop), LRC (Luda Reb Cob, a Chinese landrace, and its derivatives), and SPT (Si-ping-tou, a Chinese landrace and its derivatives). The Kullback-Leibler distance of pairwise subpopulation was also inferred as n × p (187 ×6) Q matrices, which gave a detailed percentage of genetic composition of six subpopulations and molecular relatedness of each line. The genome-wide linkage disequilibrium (LD) indicated that the asso- ciation studies in QTLs and/or candidate genes might avoid nonfunctional and spurious associations, as most of the LD blocks were broken among diverse germplasm. The defined population structure has given us a clear genetic structure of these lines for breeding practice and established a good basis for association analysis.展开更多
以田间试验为基础,对直接种植法的不同方法进行分析,以期找到适合我国的评估方法,为遗传产量增益的研究提供理论支持。以1970s—2000s期间大面积推广的杂交种为材料,分别于2005—2006年(试验1)以及2007—2008年(试验2)在新疆农业科学院...以田间试验为基础,对直接种植法的不同方法进行分析,以期找到适合我国的评估方法,为遗传产量增益的研究提供理论支持。以1970s—2000s期间大面积推广的杂交种为材料,分别于2005—2006年(试验1)以及2007—2008年(试验2)在新疆农业科学院和北京顺义试验基地进行。每个试验设置3种密度。依据1970年代单交种在3.0万株hm-2密度下的产量与2000年代的单交种在6.0万株hm-2密度下的年均单位面积的产量差异,计算得到1970s—2000s期间我国玉米遗传产量年增益速率为94.7 kg hm-2。在7.5万株hm-2密度下,2000年代单交种较1970年代单交种的产量增值是遗传因素作用的结果。1970年代单交种在1.5万株hm-2密度下的产量与2000年代单交种在7.5万株hm-2密度下的产量差值是育种与栽培共同作用的结果。由二者的比值得到育种对总产量增益的贡献率为52.9%。Duvick的直接种植法适用于我国评估遗传产量增益速率,Tollnaar的试验设置方法适用于评估我国玉米遗传贡献率。展开更多
美洲地区是全球玉米起源和遗传多样性中心,优良种质渗入是拓宽我国玉米种质基础的有效途径。通过整理和分析不同学者关于美国、国际玉米小麦改良中心(International Maize and Wheat Improvement Center,CIMMYT)和巴西玉米种质的配合力...美洲地区是全球玉米起源和遗传多样性中心,优良种质渗入是拓宽我国玉米种质基础的有效途径。通过整理和分析不同学者关于美国、国际玉米小麦改良中心(International Maize and Wheat Improvement Center,CIMMYT)和巴西玉米种质的配合力及杂种优势研究结果,鉴定出在我国可能有应用潜力的24个优良玉米群体,包括8个美国群体,8个CIMMYT群体和8个巴西玉米群体。建议在适应性改良的基础上,以我国本土化的A群和B群为核心,将群体BSSS(R)C10、BS10(FR)C14、BS13(S)C9、BSK(HI)C8 Syn 3、BR106、Pop44(C8)、Pop45(C3)与A群种质,群体BS11(FR)C14、BS16(S)C3 Syn 2、BS29(R)C3、BSCB1(R)C14、BR105、Pop42(C4)与B群种质构建复合群体,开展改良,拓宽我国玉米种质类群的遗传基础。展开更多
文摘采取混合取样策略,利用荧光SSR技术对来源于我国7个省(自治区)的90份糯玉米地方品种和6个标准测验种自交系基因组的31个简单序列重复(SSR)位点进行了分析。在90个糯玉米地方品种中,共检测出216个等位变异,每个位点检测出2~12个,平均6.97个,多态性信息量(PIC,polymorphic information content)为0.67,标记指数(MI,marker index)为4.92。可初步将90份糯玉米地方品种划为3个类群,其中,广西和贵州的糯玉米地方品种的遗传多样性相对更丰富。
文摘The inference of genome ancestry and the estimation of molecular relatedness are of great importance for breeding efficiency and association studies. Seventy SSR loci, evenly distributed in 10 chromosomes, were assayed for polymorphism among 187 commonly used maize (Zea mays L.) inbreds which represent the genetic diversity in China. The identified 290 alleles served as raw data for estimating population structure using the coalescent linked loci, based on the ADMIXTURE model. Population number, K, has been inferred to be between five and seven. Specifying five subpopulations (K = 5) led to a distinct decrease and specifying K to be greater than six resulted in only minimal increases in the likelihood value. Therefore, population number, K, has been inferred into six subpopulations, which are PA, BSSS (includes Reid), PB, Lan (Lancaster Sure Crop), LRC (Luda Reb Cob, a Chinese landrace, and its derivatives), and SPT (Si-ping-tou, a Chinese landrace and its derivatives). The Kullback-Leibler distance of pairwise subpopulation was also inferred as n × p (187 ×6) Q matrices, which gave a detailed percentage of genetic composition of six subpopulations and molecular relatedness of each line. The genome-wide linkage disequilibrium (LD) indicated that the asso- ciation studies in QTLs and/or candidate genes might avoid nonfunctional and spurious associations, as most of the LD blocks were broken among diverse germplasm. The defined population structure has given us a clear genetic structure of these lines for breeding practice and established a good basis for association analysis.
文摘以田间试验为基础,对直接种植法的不同方法进行分析,以期找到适合我国的评估方法,为遗传产量增益的研究提供理论支持。以1970s—2000s期间大面积推广的杂交种为材料,分别于2005—2006年(试验1)以及2007—2008年(试验2)在新疆农业科学院和北京顺义试验基地进行。每个试验设置3种密度。依据1970年代单交种在3.0万株hm-2密度下的产量与2000年代的单交种在6.0万株hm-2密度下的年均单位面积的产量差异,计算得到1970s—2000s期间我国玉米遗传产量年增益速率为94.7 kg hm-2。在7.5万株hm-2密度下,2000年代单交种较1970年代单交种的产量增值是遗传因素作用的结果。1970年代单交种在1.5万株hm-2密度下的产量与2000年代单交种在7.5万株hm-2密度下的产量差值是育种与栽培共同作用的结果。由二者的比值得到育种对总产量增益的贡献率为52.9%。Duvick的直接种植法适用于我国评估遗传产量增益速率,Tollnaar的试验设置方法适用于评估我国玉米遗传贡献率。
文摘美洲地区是全球玉米起源和遗传多样性中心,优良种质渗入是拓宽我国玉米种质基础的有效途径。通过整理和分析不同学者关于美国、国际玉米小麦改良中心(International Maize and Wheat Improvement Center,CIMMYT)和巴西玉米种质的配合力及杂种优势研究结果,鉴定出在我国可能有应用潜力的24个优良玉米群体,包括8个美国群体,8个CIMMYT群体和8个巴西玉米群体。建议在适应性改良的基础上,以我国本土化的A群和B群为核心,将群体BSSS(R)C10、BS10(FR)C14、BS13(S)C9、BSK(HI)C8 Syn 3、BR106、Pop44(C8)、Pop45(C3)与A群种质,群体BS11(FR)C14、BS16(S)C3 Syn 2、BS29(R)C3、BSCB1(R)C14、BR105、Pop42(C4)与B群种质构建复合群体,开展改良,拓宽我国玉米种质类群的遗传基础。