Genetic variation and selection response in model breeding populations of Brassica rapa following a diversity bottleneck
Genetic variation and selection response in model breeding populations of Brassica rapa following a diversity bottleneck
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DOI：
10.1534/genetics.105.040899
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发表时间：
2006-01-01
期刊：
影响因子：
3.3
通讯作者：
Goldman, IL
中科院分区：
文献类型：
--
作者：
Briggs, WH;Goldman, IL
驯化和育种有一个共同的特点，即群体瓶颈，然后是显着的遗传增益。到目前为止，没有作物模型研究遗传方差，选择反应，和人口多样性的发展瓶颈。我们在实验室中开发了一个模式人工选择系统，使用快速循环芜菁。子叶大小的10个周期的轮回选择的反应进行了比较，在一个广泛的人口成立与200个人，三个瓶颈人口开始与两个人，和candidate控制。加性遗传方差和遗传力显着较大的瓶颈群体选择前，这对应于一个瓶颈群体在前三个周期的响应提高。然而，在广大民众中，总体反应最终更大，更持久。AFLP标记分析表明，即使在选择群体中保留的多样性是显着有限的模式和程度的人口细分不受瓶颈。在遗传上更均匀的双核种群的快速增长，特别是在短期内，可能提供了一个解释，为什么驯化者和育种者已经实现了显着的选择进展在相对较短的时间内。
Domestication and breeding share a common feature of population bottlenecks followed by significant genetic gain. To date, no crop models for investigating the evolution of genetic variance, selection response, and population diversity following bottlenecks have been developed. We developed a model artificial selection system in the laboratory using rapid-cycling Brassica rapa. Responses to 10 cycles of recurrent selection for cotyledon size were compared across a broad population founded with 200 individuals, three bottleneck populations initiated with two individuals each, and unselected controls. Additive genetic variance and heritability were significantly larger in the bottleneck populations prior to selection and this corresponded to a heightened response of bottleneck populations during the first three cycles. However, the overall response was ultimately greater and more sustained in the broad population. AFLP marker analyses revealed the pattern and extent of population subdivision were unaffected by a bottleneck even though the diversity retained in a selection population was significantly limited. Rapid gain in genetically more uniform bottlenecked populations, particularly in the short term, may offer an explanation for why domesticators; and breeders have realized significant selection progress over relatively short time periods.