Balestre M, Von Pinho R G, Souza J C, Oliveira R L
Departamento de Biologia, Universidade Federal de Lavras, Lavras, MG, Brasil.
Genet Mol Res. 2009 Oct 27;8(4):1292-306. doi: 10.4238/vol8-4gmr644.
We evaluated the potential of genetic distances estimated by microsatellite markers for the prediction of the performance of single-cross maize hybrids. We also examined the potential of molecular markers for the prediction of genotypic values and the applicability of the Monte Carlo method for a correlation of genetic distances and grain yield. Ninety S(0:2) progenies derived from three single-cross hybrids were analyzed. All 90 progenies were genotyped with 25 microsatellite markers, including nine markers linked to quantitative trait loci for grain yield. The genetic similarity datasets were used for constructing additive genetic and dominance matrices that were subsequently used to obtain the best linear unbiased prediction of specific combining ability and general combining ability. The genetic similarities were also correlated with grain yield, specific combining ability and heterosis of the hybrids. Genetic distances had moderate predictive ability for grain yield (0.546), specific combining ability (0.567) and heterosis (0.661). The Monte Carlo simulation was found to be a viable alternative for a correlation of genetic distances and grain yield. The accuracy of genotypic values using molecular data information was slightly higher than if no such information was incorporated. The estimation of the relationship using molecular markers proved to be a promising method for predicting genetic values using mixed linear models, especially when information about pedigree is unavailable.
我们评估了通过微卫星标记估计的遗传距离对单交玉米杂交种性能预测的潜力。我们还研究了分子标记对基因型值预测的潜力以及蒙特卡罗方法在遗传距离与籽粒产量相关性方面的适用性。对源自三个单交杂交种的90个S(0:2)后代进行了分析。使用25个微卫星标记对所有90个后代进行基因分型,其中包括9个与籽粒产量数量性状位点连锁的标记。遗传相似性数据集用于构建加性遗传和显性矩阵,随后用于获得特定配合力和一般配合力的最佳线性无偏预测。遗传相似性还与杂交种的籽粒产量、特定配合力和杂种优势相关。遗传距离对籽粒产量(0.546)、特定配合力(0.567)和杂种优势(0.661)具有中等预测能力。发现蒙特卡罗模拟是遗传距离与籽粒产量相关性的一种可行替代方法。使用分子数据信息时基因型值的准确性略高于不纳入此类信息的情况。事实证明,使用分子标记估计亲缘关系是一种利用混合线性模型预测遗传值的有前景的方法,尤其是在没有系谱信息的情况下。