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Shae He Yunna Zheng Aiqun Chen Mingquan Ding Lifeng Lin Yuefen Cao Wei Zhou Junkang Rong 《Plant Breeding》2013,132(3):337-343
A well‐characterized and systematically organized collection of genetic markers is crucial in the study of any crop species. It is the basis of map‐based gene cloning and crop improvements through marker‐assisted selections. Single‐strand conformation polymorphism (SSCP) has been a robust way of discovering new polymorphisms in marker development without the requirement of sequencing. Here, we report the first approach of applying SSCP marker discovery methods in the genetic map construction and gene mapping of cotton species. A total of 80 restriction fragment length polymorphism (RFLP) markers were selected from a region on published cotton genetic maps around the T1 gene related to cotton trichome. Among the 80 RFLPs, 28 showed polymorphisms through SSCP, showing a polymorphic rate of approximately 35%, which is much higher than that of simple sequence repeat (SSR) markers in the same region (7.8%). By integrating these newly generated SSCP markers, a detailed genetic map was reconstructed around this region using an F2 population derived from a cross between Gossypium arboreum and G. herboceum. The reconstructed region comprises 22 SSCP markers, eight SSR markers and the T1 gene, spanning 21.6 cM. The marker order of the new map agrees well with published reference RFLP maps. The above results suggest that SSCP method can be applied very efficiently and reliably to the marker development of cotton genomes. It will prove to be even more valuable and robust after the public release of cotton whole‐genome sequences. 相似文献
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Chunhui Wu Yang Qiu Yundan Duan Yangdong Guo Haiping Wang Xiaohui Zhang Jiangping Song Xixiang Li 《Plant Breeding》2020,139(3):660-671
High-density marker-based QTL mapping can serve as an effective strategy to identify novel genomic information to facilitate crop improvement. In this study, we genotyped an F2 population (KB12-1 × PP12-1) using a RAD-seq approach and constructed a high-density linkage map for radish. After a series of filtering procedures were performed, 17,124 SNPs and 3,336 indels with aa × bb genotyping were retained to obtain bin markers. Then, a linkage map comprising a total of 1,221 bin markers in nine linkage groups spanning 1,467.3 cM with an average marker interval of 1.2 cM was constructed. We evaluated the resistance of the F2 mapping population to black rot using F3 progeny, and two major QTLs related to black rot resistance were identified based on this map. Among these QTLs, qBRR2 on Chr.2 explained 26.97% of the phenotypic variation with a LOD score of 11.93, and qBRR7 on Chr.7 accounted for 27.06% of the phenotypic variation with a LOD score of 11.83. The additive effect of qBRR2 was positive (14.97); however, qBRR7 had the opposite effect (−11.99). The high-density linkage map and the major QTLs qBRR2 and qBRR7 provide new important information for disease resistance gene discovery and utilization in genetic improvement. 相似文献
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以永平县林业矢量数据为例,利用91卫图助手软件和ArcGIS软件,通过北京54坐标系矢量数据在各坐标系下叠加、坐标系转换参数的计算、矢量数据坐标系的转换等步骤,阐述实现矢量数据坐标系WGS84、北京54、西安80和国家2000坐标系相互转换的方法,以实现各类自然资源矢量数据的共享。 相似文献
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以《房产测量规范》(GB/T17986.1-2000)标准绘制的分幅房产图为土地调查底图,依《土地利用现状分类》(GB/T21010-2007)标准对房产图上的土地利用现状信息进行提取。详细探讨从分幅房产图上的商业金融业用地、市政用地、公共建筑用地、交通等用地中提取地类信息的归并情况,指出从分幅房产图上提取土地利用现状信息存在的问题为:概念范围界定不统一、相同地类名称不相同、表示信息侧重点不同和精度差异等。为共享资源,节约社会成本,建议统一地类划定标准,多种地图一体化综合测绘等。 相似文献
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GIS在林业专题制图中的应用 总被引:10,自引:0,他引:10
论述了运用于理信息系统软件完成应用遥感技术进行思茅地区样地清查及进行“二项调查”的制衅工作,重点阐明了整个制作过程、成果分析、该注意的几点事项。成果得到相关部门的认可,该方法可应用于林业专题图的制作。 相似文献
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