Institute of Plant Breeding, Seed Science and Population Genetics, University of Hohenheim, 70599, Stuttgart, Germany.
Agricultural Genomics Institute, Chinese Academy of Agricultural Sciences, Shenzhen, 518120, China.
Theor Appl Genet. 2016 Oct;129(10):1901-13. doi: 10.1007/s00122-016-2748-5. Epub 2016 Jul 7.
A breeding strategy with moderate nursery selection followed by genomic selection and one-stage phenotypic selection maximizes annual selection gain for grain yield across a wide range of hybrid breeding scenarios. Genomic selection (GS) is a promising method for the selection of quantitatively inherited traits but its most effective implementation in routine hybrid breeding schemes requires further research. We compared five breeding strategies and varied their available budget, the costs for doubled haploid (DH) line and hybrid seed production as well as variance components for grain yield in a wide range. In contrast to previous studies, we included a nursery selection for disease resistance just before GS on grain yield. The breeding strategy GSrapid with moderate nursery selection followed by one stage GS and one final stage with phenotypic selection on grain yield had the highest annual selection gain across all strategies, budgets, costs and variance components considered and we, therefore, highly recommend its use in hybrid breeding of cereals. Although selecting on traits not correlated with grain yield in the observation nursery, this selection reduced the selection gain of grain yield, especially in the breeding schemes with GS and for selected fractions smaller than 0.3. Owing to the very high number of test candidates entering breeding strategies with GS, the costs for DH line production had a larger impact on the annual selection gain than the hybrid seed production costs. The optimum allocation of test resources maximizing annual selection gain in classical two-stage phenotypic selection on grain yield and for the recommended breeding strategy GSrapid is finally explored for maize, wheat, rye, barley, rice and triticale.
在广泛的杂交种选育情景下，采用中等规模的苗圃选择、随后进行基因组选择和单阶段表型选择的选育策略，可以最大限度地提高谷物产量的年度选育增益。基因组选择（GS）是一种用于选择数量遗传性状的有前途的方法，但要在常规杂交种选育计划中最有效地实施，还需要进一步研究。我们比较了五种选育策略，并根据可用预算、双单倍体（DH）系和杂交种子生产的成本以及谷物产量的方差分量，在广泛的范围内对其进行了变化。与以前的研究不同，我们在对谷物产量进行 GS 之前，就进行了对抗病性的苗圃选择。中等规模的苗圃选择后，紧接着是一个阶段的 GS 和一个最终阶段的基于表型的谷物产量选择的 GSrapid 选育策略，在所有考虑的策略、预算、成本和方差分量下，具有最高的年度选育增益，因此，我们强烈推荐在谷物的杂种选育中使用该策略。尽管在观测苗圃中选择与谷物产量不相关的性状，但这种选择会降低谷物产量的选育增益，特别是在具有 GS 的选育计划中，以及选择分数小于 0.3 时。由于进入具有 GS 的选育策略的测试候选者数量非常多，DH 系生产的成本对年度选育增益的影响大于杂交种子生产的成本。最后，针对经典两阶段基于表型的谷物产量选择和推荐的 GSrapid 选育策略，探讨了最大化年度选育增益的测试资源最优分配。
