Genetic Variation and Provenance Selection of Chinese Tuliptree

WT5BZ]Fifteen provenances were sampled in the distribution areas of Chinese Tuliptree(Liriodendron chinense) and the trial plantations were simultaneously established in 5 sites along the middle and lower reaches of Yangtze River in 1991. The main growth characteristics, including height(H), diameter at breast height(DBH) and range of tree crown(RC) were all measured respectively when in the seventh year and the variance analysis were conducted. The results showed that there were significant differences among provenances(FH=29.5,FDBH =10.02,FRC=4.1),which indicated potentiality of selection and genetic improvement, and there were significant differences among sites, which indicated Chinese Tuliptree was sensitive to environment, and there were also significant differences among mutual actions of provenances and sites. The heritabilities of height, DBH and volume for provenance are all more than 0.5 which shows a strongly genetic control in growth characteristics and a good genetic gain can be acquired by provenance selection. The analysis of genetic stability, growth andaptability and correlation between juvenile and mature were conducted, which provided bases for provenance selection and evaluation. The provenance selection and evaluation were conducted in multi sites'and single site’s way respectively. Liping and Xuyong provenances were picked out from all five sites in multi sites selection and the genetic gain was 11.8%, and one to three provenances were respectively picked out for each site in single site’s selection and the genetic gain was 15.4%～51.5% higher than multi site.