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在林木改良中,人们对多倍体现象早已注意了。Wright 1976年论述了多倍体的优点,探讨了利用的途径。针叶树多倍性的试验多数不成功,因针叶树染色体的数量较大,染色体组型较相似,基本染色体的数量变化很小(n=11或12最多)。针叶树天然多倍性现象很罕见,据文献记载唯有北美红杉(6n)、圆柏(4n)和金钱松(4n)有多倍性。也曾培育了松、云杉和落叶松的人工四倍体,但一般生长慢,矮小,仅在园艺上有用。
In the forest improvement, people pay attention to the phenomenon of polyploid. Wright 1976 discusses the advantages of polyploidy and explores ways to utilize it. Most of conifers were unsuccessful because of the large number of conifer chromosomes and the similar chromosome constitutions. The number of basic chromosomes changed little (n = 11 or 12). Conifer natural polyploidy phenomenon is very rare, according to the literature records only North American Sequoia (6n), Sabina (4n) and money pity (4n) polyploidy. Artificial tetraploids of pine, spruce and larch have also been cultivated, but generally grow slowly and are short and are only useful in horticulture.