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美洲赤松(Pinus resinosa Ait)主要分布在 Great Lakesst.Lawrence 林管区和Acadian 林管区(Rowe 1972)。因它干形良好,生长速度均匀,喜沙壤土,在安大略(Ontario)和 Quebec 已大面积造林。1900—1965年加拿大(Cayford 和 Bickersfaff1968)营造美洲赤松145,000英亩。美洲赤松是否适于遗传改良已进过热烈讨论,Fowler(1964a)提到,美洲赤松的遗传性是迄今为止的研究所有松树种中最稳定的;所以优良个体或品种的选择可能是无效的。随后(Fowler 和 Heimburger(1969)估计,美洲赤松的遗传改良是困难的,但决不是不可能的。预期的改良与加拿大所产的其他针叶树相比将是小的,但在粗放造林的地方,甚至美洲赤松改良不大,而在经济上也是有利的。Petawawa 林业试验站的
Pinus resinosa Ait is mainly distributed in Great Lakesst. Lawrence Forest Area and Acadian Forest Area (Rowe 1972). Because of its good dry nature, uniform growth rate, hi sandy loam, large-scale afforestation in Ontario and Quebec. 1900-1965 Canada (Cayford and Bickersfaff1968) Created 145,000 acres of American red pine. Whether or not American red pine is suitable for genetic improvement has been the subject of intense discussion. Fowler (1964a) mentioned that the geneticity of American red pine is by far the most stable of all pine species in the study; hence the selection of good individuals or breeds may not be valid. Subsequently (Fowler and Heimburger (1969) estimate that genetic improvement of Pinus thunbergii is difficult, but by no means impossible.) The expected improvements will be small compared to other conifers produced in Canada, but in areas where extensive afforestation, Even Pinus thunbergii improved little, but economically favored.Petawawa forestry pilot station