Department of Breeding Research, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, Germany.
Nat Genet. 2017 Dec;49(12):1741-1746. doi: 10.1038/ng.3974. Epub 2017 Oct 16.
Increasing wheat yield is a key global challenge to producing sufficient food for a growing human population. Wheat grain yield can be boosted by exploiting heterosis, the superior performance of hybrids compared with midparents. Here we present a tailored quantitative genetic framework to study the genetic basis of midparent heterosis in hybrid populations derived from crosses among diverse parents. We applied this framework to an extensive data set assembled for winter wheat. Grain yield was assessed for 1,604 hybrids and their 135 parental elite breeding lines in 11 environments. The hybrids outperformed the midparents by 10% on average, representing approximately 15 years of breeding progress in wheat, thus further substantiating the remarkable potential of hybrid-wheat breeding. Genome-wide prediction and association mapping implemented through the developed quantitative genetic framework showed that dominance effects played a less prominent role than epistatic effects in grain-yield heterosis in wheat.
提高小麦产量是全球面临的一项重大挑战，这对于养活不断增长的人口至关重要。杂种优势可提高小麦籽粒产量，杂种表现优于双亲的平均值。本研究提出了一个定制的数量遗传学框架，用于研究来自不同亲本杂交的杂种群体中双亲杂种优势的遗传基础。我们将该框架应用于一个广泛的冬小麦数据集，评估了 11 个环境下 1604 个杂种及其 135 个亲本优良育成系的籽粒产量。杂种平均比中亲高出 10%，代表了小麦 15 年的育种进展，进一步证实了杂种小麦育种的巨大潜力。通过开发的数量遗传学框架进行的全基因组预测和关联分析表明，在小麦籽粒产量杂种优势中，显性效应的作用不如上位性效应突出。
