New genotypes of hybrid poplars from theAigeirosandTacamahacasections have great potential for increasing genetic gain from selection. The most promising traits are associated with productivity and resistance toSphaerulina musiva-induced canker while wood density can be selected for secondarily. A minimum age of 8 years is reliable to select fast-growing resistant clones in northern climates. Productivity, wood density, and disease resistance of hybrid poplar clones are important traits when selecting for cultivation at an industrial scale. We studied 1978 hybrid poplar clones from 63 families, bred from poplars native (Populus balsamifera and Populus deltoides) and non-native to Canada from the Aigeiros and Tacamahaca sections, to improve economically important traits for plantations in northern Alberta. Genetic parameters for diameter at breast height (DBH), height, resistance to Sphaerulina musiva-induced canker, and wood density were determined up to age 10. A mean annual increment of 16.5 m3 ha−1 year−1 was achieved at age 10 in the best-performing clones. The potential genetic gain for DBH, height, and canker resistance, 37%, 26%, and ~ 13%, respectively, was achieved when selecting the top 10% of the tested clones. The genetic effect for wood density was weak. The age-age genetic correlations identified age eight as a reliable selection age. The new hybrid poplar clones tested exhibited great potential for tree improvement. The next phase of selection should test a reduced number of clones on different site types, identifying stable clones for productivity and resistance, while wood density can be selected for secondarily. In northern regions, a minimum age of 8 years is reliable to select fast-growing resistant clones for commercial deployment.

中文翻译：

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生长参数和对 Sphaerulina musiva 诱导的溃疡病的抵抗力比木材密度更重要，可用于增加杨树品种的遗传增益。适合北方气候的杂交种

来自 Aigeiros 和 Tacamahacasections 的杂交杨树的新基因型具有通过选择增加遗传增益的巨大潜力。最有希望的性状与生产力和对球藻引起的溃疡病的抵抗力有关，而木材密度可以作为其次。在北方气候中选择快速生长的抗性克隆的最低年龄为 8 岁是可靠的。选择工业规模栽培时，杂交杨树无性系的生产力、木材密度和抗病性是重要的性状。我们研究了来自 63 个科的 1978 年杂交杨树无性系，它们是从 Aigeiros 和 Tacamahaca 部分的本地杨树（Populus balsamifera 和 Populus deltoides）和非加拿大本地杨树繁殖的，以改善阿尔伯塔省北部种植园的经济重要特性。胸高直径 (DBH)、高度、对球藻诱导的溃疡病的抵抗力和木材密度的遗传参数在 10 岁时确定。在 10 岁时实现了 16.5 m3 ha-1 年-1 的平均年增量性能最好的克隆。The potential genetic gain for DBH, height, and canker resistance, 37%, 26%, and ~ 13%, respectively, was achieved when selecting the top 10% of the tested clones. 木材密度的遗传效应较弱。年龄-年龄遗传相关性将八岁确定为可靠的选择年龄。测试的新杂交杨树无性系展示了树木改良的巨大潜力。下一阶段的选择应该在不同的场地类型上测试减少数量的克隆，确定生产力和抗性的稳定克隆，而木材密度可以作为次要选择。