Ritland Kermit, Ritland Carol
Department of Botany, University of Toronto, Toronto, Ontario, M5S 3B2, Canada.
Evolution. 1996 Jun;50(3):1074-1082. doi: 10.1111/j.1558-5646.1996.tb02348.x.
We used a nonmanipulative, marker-based method to study quantitative genetic inheritance in two habitats of a common monkeyflower population. The method involved regressing quantitative trait similarity on marker-estimated relatedness between individuals sampled in the field. We sampled 300 adult plants from each of two transects, one along a stream habitat and another through a meadow habitat. For each plant we measured 10 quantitative characters and assayed 10 polymorphic isozyme loci. In the meadow habitat, relatedness of plants within 1 m was moderate (r = 0.125, corresponding to half-sibs) as was actual variance of relatedness (V = 0.044). Significant heritabilities of 50-70% were found for corolla width and the fitness characters of flower number and plant weight. Genetic correlations were strongly positive, but sharing of environmental effects within 1 m was weak. In the stream habitat, levels of relatedness were lower and similar heritabilities were indicated. To detect dominance variance and the correlation of phenotypes due to shared inbreeding, we also estimated higher-order coefficients of relationship and inbreeding, but these did not significantly differ from zero. Laboratory-based estimates of heritability in the field were lower than the marker-based estimates, indicating that natural heritabilities and genetic correlations may be stronger than indicated by controlled studies.
我们采用了一种非操纵性的、基于标记的方法，来研究一种常见猴面花种群在两个栖息地中的数量遗传。该方法包括将数量性状相似性对野外采样个体间基于标记估计的亲缘关系进行回归分析。我们从两条样带中各采集了300株成年植株，一条沿着溪流栖息地，另一条穿过草地栖息地。对于每株植物，我们测量了10个数量性状，并检测了10个多态同工酶位点。在草地栖息地，1米范围内植株的亲缘关系适中（r = 0.125，相当于半同胞），亲缘关系的实际方差也是如此（V = 0.044）。对于花冠宽度以及花朵数量和植株重量等适合度性状，发现了50 - 70%的显著遗传力。遗传相关性呈强正相关，但1米范围内环境效应的共享较弱。在溪流栖息地，亲缘关系水平较低，但显示出相似的遗传力。为了检测显性方差以及由于共同近亲繁殖导致的表型相关性，我们还估计了高阶亲缘系数和近亲繁殖系数，但这些系数与零没有显著差异。基于实验室的野外遗传力估计值低于基于标记的估计值，这表明自然遗传力和遗传相关性可能比对照研究显示的更强。
