Am J Bot. 1997 Apr;84(4):461.
The mating system of the tropical rainforest tree Carapa procera was studied for a population located within a sylvicultural trial in French Guiana. We used the mixed-mating model with the genotypes of 47 open-pollinated progenies at ten polymorphic loci, obtained through isozyme analysis. Seeds were collected on both logged and unlogged (control) plots, which were interspersed. A high multilocus outcrossing rate (0.78) was found for the global population. and there was indirect evidence for nonrandom mating for outcrosses. It is argued that this may be due to some kind of positive assortative mating, probably biparental inbreeding. Correlation of selfing between sibs was not significantly different from zero. and the proportion of full-sibs among outcrossed sib-pairs was significant but low (0.16). We found significant differences between outcrossing rates when computing separate estimates for the 14 trees located on logged plots (tm = 0.63) and the 33 trees located on undisturbed plots (tm = 0.85). It is argued that the decrease in density is probably not the only cause of the decrease in outcrossing rate on logged plots. Lastly, several points concerning the reliability of the estimation are outlined. In particular. the downward bias due to ignoring null alleles during genetic interpretations of zymograms is quantified in a few cases by simulating artificial populations.
我们对法属圭亚那一个人工林试验中热带雨林树种 Carapa procera 的交配系统进行了研究。利用混合交配模型，以十个多态性位点的 47 个自由授粉后代的基因型为基础，通过同工酶分析获得。在砍伐和未砍伐（对照）的样地中收集种子，样地相互交错。总体种群的多座位异交率很高（0.78），并且存在异交的非随机交配的间接证据。有人认为，这可能是由于某种正交配（可能是双亲近亲繁殖）。同胞间自交的相关性与零无显著差异，异交同胞对中全同胞的比例显著但较低（0.16）。我们发现，当分别计算位于砍伐样地的 14 棵树（tm = 0.63）和位于未干扰样地的 33 棵树（tm = 0.85）的异交率的单独估计值时，异交率存在显著差异。有人认为，密度的降低可能不是砍伐样地异交率降低的唯一原因。最后，还概述了一些与估计可靠性有关的问题。特别是，在对同工酶图谱进行遗传解释时忽略无效等位基因，会导致估计值产生向下偏差，在少数情况下，通过模拟人工种群来量化这种偏差。
