论文部分内容阅读
当前,在所有进行集约经营的林业发达国家中,将乔木树种的遗传和选种方面的成就广泛用于森林培育工作的必要性已为人们所公认。普遍认为,在营林生产中利用选种方法,以及改为只用改良的类型和品种营造人工林,即可使森林的生产率提高10—25%,在某些情况下甚至可达45—50%。七十年代,我国已开始有计划地建立固定林木种子基地。这些基地可持续地为造林生产提供主要森林树种的遗传特性珍贵的种子。为此,采用分析选种作为主要方针,即
At present, the need to widely apply the achievements in genetic and seed selection of tree species to forest cultivation in all intensively developed forestry developed countries is well recognized. It is generally agreed that the use of selection methods in silviculture and the conversion of only plantations with improved types and varieties will result in a 10-25% increase in forest productivity and in some cases up to 45-50 %. In the seventies, our country has started the planned establishment of a fixed tree seed base. These bases sustainably provide precious seeds for afforestation production with the genetic characteristics of the major forest species. To this end, the use of analysis and selection as the main principle, that is