Department of Animal Science, Agricultural University of Norway, P.O. Box 5025, 1432 ÅS, Norway.
Theor Appl Genet. 1994 Nov;89(6):687-92. doi: 10.1007/BF00223706.
When selecting in a finite population of honeybees there is a conflict between gain in a quantitative trait and increasing homozygosity, and therefore the frequency of inviable diploid drones. The consequences when using different mating, import, and selection strategies on diploid drone frequency and genetic gain, was explored with Monte Carlo computer simulations.Within a closed population breeding structure, mass selection gave the highest genetic gain in the quantitative trait, but also the largest increase in percentage diploid drones and queens with unacceptably-low brood viability. Mass selection combined with truncation selection against queens having more than 15% diploid drones gave a comparable genetic gain and was the best strategy of the ones studied to avoid diploid drones. Within-family selection (one replacement per sib group) gave the least genetic gain, and a frequency of diploid drones comparable to random (no) selection. It was intermediate between mass selection and mass selection combined with viability selection concerning the frequency of diploid drones.Insemination with pooled and homogenized semen originating from all breeder queens (30), as compared to natural mating with 12 randomly-selected drones, had little effect on the genetic gain and on the overall frequency of diploid drones (10 to 15% by generation 20).The effect of opening the closed breeding population for the import of external queens every generation, by exchanging breeder queens of lowest performance with a corresponding number of new queens (5, 10and 15 out of 30), was also investigated. Under mass selection (natural mating as well as artificial insemination) the frequency of diploid drones and the proportion of queens discarded were reduced because of low brood viability. However, artificial insemination was superior to natural mating considering the latter criterion. If the imported queens were at the same genetic level for the quantitative trait under selection as the whole breeding population at that generation, or 10% better, the genetic gain was respectively slightly reduced and approximately maintained. If the imported queens were of inferior quality (equal to the initial population) the import of queens slowed genetic progress considerably.
在有限的蜜蜂群体中进行选择时，存在一个问题，即数量性状的增益与增加同型合子之间存在冲突，因此二倍体不育雄蜂的频率也会增加。本研究采用蒙特卡罗计算机模拟方法，探讨了在二倍体雄蜂频率和遗传增益方面使用不同交配、引种和选择策略的后果。在封闭种群的繁殖结构中，大规模选择在数量性状方面获得了最高的遗传增益，但也使具有不可接受低育性的二倍体雄蜂和蜂王的比例增加了。大规模选择与针对具有超过 15%二倍体雄蜂的蜂王进行截选相结合，获得了可比的遗传增益，是避免二倍体雄蜂的最佳策略之一。家系内选择（每一个家系组替换一只）获得的遗传增益最小，二倍体雄蜂的频率与随机（无）选择相当。与大规模选择和大规模选择与生存力选择相结合相比，其在二倍体雄蜂的频率方面处于中间位置。与用 30 只繁殖蜂王混合精液的人工授精相比，用 12 只随机选择的雄蜂自然交配对遗传增益和整体二倍体雄蜂频率（第 20 代时 10%至 15%）几乎没有影响。还研究了每代开放封闭繁殖群体以引入外部蜂王的方式，即用最低性能的繁殖蜂王与相应数量的新蜂王（30 只中有 5、10 和 15 只）进行交换。在大规模选择（自然交配和人工授精）下，由于幼蜂活力低，二倍体雄蜂的频率和被淘汰的蜂王比例降低。然而，人工授精在考虑后一标准时优于自然交配。如果引入的蜂王在选择的数量性状上与该代整个繁殖群体具有相同的遗传水平，或者比整个繁殖群体好 10%，则遗传增益分别略有降低和基本保持。如果引入的蜂王质量较差（与初始群体相同），则蜂王的引入会大大减缓遗传进展。
