基于60K芯片的玉米回交群体精准背景选择策略

利用Maize 6H-60K芯片对京724/京92/京92的BC1代群体进行分子标记辅助背景选择,结合SNP数据特征和回交群体分离特征,开发出一套精准背景选择策略(ABSS:Accurate Background Selection Strategy)及相关算法。从统计结果中选取背景回复程度最高的一批单株作为下一代回交群体的亲本材料。基于Maize 6H-60K芯片分析和筛选产生的28 910个多态性位点,可以对727个样品的背景回复程度进行精细排序,样品背景回复率大部分分布在0.30～0.75(约占样品总数的94.1%),背景回复率在0.75及以上的样品比例为1.8%。通过分析回交群体重组交换规律以及背景回复率与株高的相关性,进一步验证Maize 6H-60K芯片数据和ABSS的准确性。利用Maize 6H-60K芯片结合ABSS可以精细选择背景回复程度高、重组交换频率相对较低的单株,显著提高背景选择效率,为设计玉米回交群体规模提供参考价值。

Accurate Background Selection Strategy for Maize Backcross Population Based on 60K-array

Using the Maize 6H-60K array to perform molecular marker-assisted background selection on the BC₁ generation population of J724/J92/J92, and a set of ABSS (Accurate Background Selection Strategy) and related algorithms were developed based on SNP data characteristics and backcross population separation characteristics. Samples with high background recovery rate were selected as the parent material of the next generation backcross population. Based on the 28 910 polymorphic loci generated by Maize 6H-60K array analysis and screening, the background recovery rate of 727 samples were finely sorted. The background recovery rate of samples is mostly between 0.30-0.75 (approximately 94.1% of the total number of samples), and the proportion of samples with background recovery rate of 0.75 and above was 1.8%. The accuracy of Maize 6H-60K array data and ABSS was further verified by analyzing the recombination and exchange rules of backcross population and the correlation between background recovery rate and plant height. Using the Maize 6H-60K array combined with ABSS can select individual plants with a high background recovery rate and a relatively low frequency of recombination exchange, which significantly improves the efficiency of background selection, and provide reference value for designing the size of the maize backcross population.