Abstract:
Modern breeding structures are emerging for European honeybee populations. However, while genetic evaluations of honeybees are becoming increasingly well understood, little is known about how selection decisions shape the populations\' genetic structures. We performed simulations evaluating 100 different selection schemes, defined by selection rates for dams and sires, in populations of 200, 500, or 1000 colonies per year and considering four different quantitative traits, reflecting different genetic parameters and numbers of influential loci. Focusing on sustainability, we evaluated genetic progress over 100 years and related it to inbreeding developments. While all populations allowed for sustainable breeding with generational inbreeding rates below 1% per generation, optimal selection rates differed and sustainable selection was harder to achieve in smaller populations and for stronger negative correlations of maternal and direct effects in the selection trait. In small populations, a third or a fourth of all candidate queens should be selected as dams, whereas this number declined to a sixth for larger population sizes. Furthermore, our simulations indicated that, particularly in small populations, as many sires as possible should be provided. We conclude that carefully applied breeding provides good prospects for currently endangered honeybee subspecies, since sustainable genetic progress improves their attractiveness to beekeepers.
摘要:
欧洲蜜蜂种群正在出现现代繁殖结构。然而,虽然蜜蜂的遗传评估越来越被人们所理解,关于选择决定如何塑造种群的遗传结构,人们知之甚少。我们进行了模拟,评估了100种不同的选择方案,由大坝和父亲的选择率定义,在每年200、500或1000个菌落的种群中,考虑到四个不同的数量性状,反映不同的遗传参数和有影响的基因座数量。注重可持续性,我们评估了100多年的遗传进展,并将其与近交发展联系起来。虽然所有种群都允许可持续育种,每代近亲繁殖率低于1%,最佳选择率不同,可持续选择在较小的人群中更难实现,并且在选择性状中母性和直接效应之间存在更强的负相关。在小人口中,所有候选女王中的三分之一或四分之一应该被选为水坝,而对于更大的人口,这个数字下降到六分之一。此外,我们的模拟表明,特别是在小人口中,应该提供尽可能多的父亲。我们得出的结论是,精心应用的育种为目前濒临灭绝的蜜蜂亚种提供了良好的前景,因为可持续的遗传进步提高了他们对养蜂人的吸引力。