玉米骨干自交系吉853的遗传结构初探

本研究利用59对SSR引物对吉853、黄早四、自330等8份玉米自交系进行了分析，结果表明:吉853和黄早四之间的遗传相似性最大（GS=0.71），与自330有较大的遗传差异（GS=0.55）。黄早四和自330在吉853中的等位基因流向分为4种类型，第1种是3个自交系带型均相同，占26.67%，属于未发生重组位点；第2种是来自黄早四的等位基因，占33.33%；第3种是来自自330的等位基因，只占11.67%；第4种是与黄早四和自330均不同的带型，属变异重组的位点，占28.33%，且有集中分布的趋势，主要集中于4个区段（Bin2.0-Bin2.03、Bin3.02-Bin3.05、Bin5.01-Bin5.04和Bin8.08），这些重组变异也大大丰富了吉853的遗传多样性。本研究证明了在二环选系重组过程中也会发生相当程度的变异，表明二环选系在今后依然是玉米育种的重要方法。 

Preliminary Analysis of Genetic Structure for Elite Maize Inbred Line Ji 853

In this study，we investigated genetic structure of 8 maize inbred line with 59 SSR markers. The results showed that inbred line Ji 853 has most high genetic similarity coefficient（GS=0.71）with inbred line Huang zao si, but has rather genetic difference（GS=0.55）with inbred line Zi 330. There were four types for alleles flow from inbred line Huang zao si and Zi 330 in the genetic background of inbred line ji 853. The proportion of first type loci from both parents was 26.67%. These loci belonged to non-recombinant loci. The second type from inbred line Huang zao si’s alleles was 33.33%. The third type from inbred line Zi 330’s alleles was 11.67%. The forth type that was different from inbred line Huang zao si and inbred line Zi 330’s alleles was 28.33%. The recombinant loci focused on four regions (Bin2.0-Bin2.03, Bin3.02-Bin3.05, Bin5.01-Bin5.04 and Bin8.08). These mutations greatly enriched genetic diversity of inbred line Ji 853. This study proved that second cycle inbred lines is still an important breeding methods in future because of considerable mutations happened in selection of second cycle inbred lines.