Analysis of QTLs for Root Traits at Seedling Stage in Soybean

Very few quantitative trait loci (QTLs) for root traits have been identified in soybean [Glycine max (L.) Merr.], although root system plays important roles in the growth and development of a plant. The aim of this study was to localize QTLs for root traits at seedling stage in soybean. The mapping population contained 165 recombinant inbred lines (RILs), which was derived from the cross between Zhongdou 29 and Zhongdou 32. The seedlings were hydroponically cultured, and the root traits, including length of the main root, number of lateral roots, root weight, root volume, plant weight, shoot weight per plant, and ratio of root weight to shoot weight, were measured at V2 stage. Using composite interval mapping (CIM) method, 20 QTLs associated with roots and aerial part traits were mapped on 8 chromosomes, which included 9 major-effect QTLs on chromosomes 11 and 14 with the phenotypic contributions of 10.5-26.1%. On chromosomes 11 and 14, some QTLs for root traits and aerial part traits were distributed in clusters. This result is consistent with the correlation analysis of phenotypic traits, indicating that the root traits are associated with the shoot traits.

摘要为了研究玉米异交不亲和的蛋白表达机制, 以玉米(Zea mays L.)异交不亲和基因Gal-S的一对近等基因系W22(GG)与w22(gg)为材料, 组配自交(GG×GG)、正交(gg×GG)与反交(GG×gg) 3个组合。首先采用荧光显微技术, 观察比较了3个组合中花粉管在花丝中的生长过程; 其次采用IEF/SDS-PAGE双向凝胶电泳与基质辅助激光解吸电离飞行时间质谱(MALDI-TOF-MS)技术, 比较研究了授粉后10 h自交与反交母本W22(GG)花丝蛋白质组的特异表达差异。结果表明, 授粉后10 h, 自交与正交花粉管伸长可达花丝基部, 而反交花丝基部未观察到花粉管; 自交与反交母本W22(GG)花丝蛋白质组共检测到25个差异蛋白质点, 其中15个在自交中特异表达, 10个在反交中特异表达。通过MALDI-TOF-MS质谱测序和MASCOT序列分析, 注释了12个蛋白质点, 其中自交中特异表达的蛋白质点11、12、14和异交中特异表达的蛋白质点18、22、24可能与玉米异交不亲和密切相关。