杉木的树种改良,目前主要是通过在适宜的种源区内选择优树,建立种子园,使优树间相互授粉,优良基因更加集中于子代,生产种子而实现的。尽管杉木比较速生,由播种到开花结实的年代较短,但要通过世代更替来鉴定中选优树的遗传性优劣,还是需要一定年代的;而提高育种效率的关键是缩短育种周期,只能较早的根据幼年期的表现作出成龄期遗传性优劣的判断,才可实现缩短周期。所以很早以来世界上一些树种改良学家就致力于性状的早期诊断和幼龄选择。如本世纪三十年代,什 Cunninghamia lanceolata tree species improvement, mainly through the appropriate provenance area to choose the best tree, the establishment of seed orchards, pollination between trees, polo ralph lauren pas cher, superior genes more concentrated in the offspring, the production of seeds and achieve. Although fir is relatively fast growing, from sowing to flowering sturdy age is shorter, but to pass the generations to identify the superiority and inferiority of selected superiority tree, or need a certain age; and improve the breeding efficiency of the key is to shorten the breeding cycle, only Earlier according to the performance of juvenile age to make the judgment of the hereditary advantages and disadvantages, can shorten the cycle. Therefore, some early tree warriors in the world devoted themselves to the early diagnosis of traits and young people’s choices. As the thirties of this century, what