Abstract A teak progeny trial was established with four replicates at different sites along the northern Pacific region of Costa Rica. The trials followed a randomized block design, with 28 open pollinated families and 36 seedlings per family per site. Data from 7 years-old trees was analyzed both for each test location separately and for all locations combined. High individual heritability was found for diameter, which translates to higher breeding potential. The all locations combined analysis showed high genetic variation, with individual heritabilities reaching up to 22 %. Genotype by Environment (GxE) interactions explained only 2.5 % of total phenotypic variation. The genetic correlation (rg) among all four sites was 0.69. Hence, it is concluded that GxE interactions are not problematic for breeding purposes since they are not complex in nature. This teak breeding population showed strong genetic stability and performed well in most environments in the study area. The Hojancha location showed high genetic correlation with all other sites; therefore, it should be chosen for future testing and selection of elite genotypes. Selection of the 20 best individuals, allowing for up to two individuals per family, would result in a 1.78 cm (11 %) gain in diameter. Furthermore, based on this selection the inbreeding coefficient (F) in the offspring would only reach 2.9 %, while the expected effective population size (Ne) would be16.97 individuals. This selection scheme could reduce rotation age by almost two years, since the diameter goal of 40 cm would be reached earlier than the usual 20 years cycle. The results suggest that the progeny trial can be maintained as a single breeding population, suitable for planting in any site along the Northern Pacific region of Costa Rica.

中文翻译：

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哥斯达黎加环境相互作用和柚木 (Tectona grandis L.) 选择的基因型

摘要 建立了柚木后代试验，在哥斯达黎加北太平洋地区的不同地点进行了四次重复。试验遵循随机区组设计，每个地点有 28 个开放授粉家庭和 36 个幼苗。分别针对每个测试位置和所有位置的组合分析了来自 7 年树龄的树木的数据。发现直径具有较高的个体遗传力，这意味着更高的育种潜力。所有地点联合分析显示高遗传变异，个体遗传率高达22%。环境基因型 (GxE) 相互作用仅解释了总表型变异的 2.5%。所有四个位点之间的遗传相关性 (rg) 为 0.69。因此，结论是 GxE 相互作用对于育种目的没有问题，因为它们本质上并不复杂。这个柚木育种种群表现出很强的遗传稳定性，在研究区的大多数环境中表现良好。Hojancha 位置显示出与所有其他站点的高度遗传相关性；因此，它应该被选择用于未来的测试和精英基因型的选择。选择 20 个最佳个体，允许每个家庭最多两个个体，将导致直径增加 1.78 厘米（11 %）。此外，基于这种选择，后代的近亲繁殖系数 (F) 将仅达到 2.9%，而预期的有效种群大小 (Ne) 将为 16.97 个个体。这种选择方案可以将轮换年龄减少近两年，因为 40 厘米的直径目标将比通常的 20 年周期更早实现。结果表明，后代试验可以作为单一繁殖种群维持，适合在哥斯达黎加北太平洋地区的任何地点种植。