Genetic Variation of Liquidambar formosana Progeny Testing at Year 3 and 9 and Family Selection

Based on data of 84 progenies of firstling forest of Liquidambar formosana located in Qimen County of Anhui Province,basal diameter,tree height,the genetic traits and genetic gain of tree height were analyzed between forest of 9-years-old and 3-years-old,then conducted fine family selection.The results showed that the name,quantity and position of the family of different selected period appeared large differences.Parameter estimation of the most families,such as diameter,the family genetic traits of tree height,and individual heritability and genetic gain parameters,decreased with forest age increasing,which provides a reference for the appropriate forest age selection in Liquidambar breeding.