GENETIC VARIATION IN INBREEDING DEPRESSION IN THE RED FLOUR BEETLE TRIBOLIUM CASTANEUM
GENETIC VARIATION IN INBREEDING DEPRESSION IN THE RED FLOUR BEETLE TRIBOLIUM CASTANEUM
复制标题
红谷盗近交抑制的遗传变异
DOI：
--
复制
发表时间：
1995
期刊：
影响因子：
--
通讯作者：
C. Goodnight
中科院分区：
文献类型：
--
作者：
L. Pray;C. Goodnight
近交衰退在物种之间和一个物种内的种群之间各不相同。然而，很少有研究考虑到近交衰退在单一种群中的变化程度。我们报告的两个实验提供的证据表明，近交衰退是遗传变量，在一个单一的人口，一些血统遭受严重的近交衰退，其他人只遭受轻度的近交衰退，和一些血统实际上增加表型值在较高水平的近交。我们研究了种群结构对近交衰退的影响，第一个实验中有两个性状（成年干重和雌性相对适合度），第二个实验中有七个性状（雌性和雄性成年干重，雌性和雄性相对适合度，雌性和雄性发育时间，以及卵到成虫的活力）。在第一个实验中，我们收集了来自38个谱系中每个谱系的4个家庭的数据，这些谱系来自一个单一的祖先种群，并保持了四代全同胞交配。这两个性状都表现出显着的近交衰退，并提供证据表明，即使在一个单一的血统有显着的遗传变异的近交衰退。在第二个实验中，我们收集了来自第一个实验中使用的相同祖先群体的15个谱系中的每一个的5个重复的数据;这些谱系保持了四代全同胞交配。我们还收集了每一代远交对照甲虫的数据，并将这些数据纳入分析，以公正的方式考虑环境影响。除雌、雄发育时间外，其余性状均表现出显著的近交衰退。所有显示近交衰退的性状在近交衰退中都是遗传可变的，这从显著的线性谱系-×-f分量中可以看出。对于这两个实验，种群结构对近交衰退的影响是进一步明显的，从增加的变化量，可以解释用于测量近交衰退的模型时，包括额外的水平的种群结构。近交衰退中的遗传变异对保护生物学具有重要意义，可能是交配系统进化的重要因素。
Inbreeding depression varies among species and among populations within a species. Few studies, however, have considered the extent to which inbreeding depression varies within a single population. We report on two experiments to provide evidence that inbreeding depression is genetically variable, such that within a single population some lineages suffer severe inbreeding depression, others suffer only mild inbreeding depression, and some lineages actually increase in phenotypic value at higher levels of inbreeding. We examine the effects of population structure on inbreeding depression for two traits in the first experiment (adult dry weight and female relative fitness), and for seven traits in the second experiment (female and male adult dry weight, female and male relative fitness, female and male developmental time, and egg‐to‐adult viability). In the first experiment, we collected data from 4 families within each of 38 lineages derived from a single ancestral stock population and maintained for four generations of full‐sib mating. Both traits demonstrate significant inbreeding depression and provide evidence that even within a single lineage there is significant genetic variability in inbreeding depression. In the second experiment, we collected data from 5 replicates for each of 15 lineages derived from the same ancestral population used in the first experiment; these lineages were maintained for four generations of full‐sib mating. We also collected data on outbred control beetles in each generation and incorporated these data into the analyses to account for environmental effects in an unbiased manner. All traits except female and male developmental time show significant inbreeding depression. All traits showing inbreeding depression are genetically variable in inbreeding depression, as is evident from a significant linear lineage‐×‐f component. For both experiments, the effect of population structure on inbreeding depression is further evident from the increasing amount of variation that can be explained by the models used to measure inbreeding depression when additional levels of population structure are included. Genetic variation in inbreeding depression has important implications for conservation biology and may be an important factor in mating‐system evolution.