Selection of excellent families and analysis on growth variation for the 12-year-old half-sib family of seed orchard of Pinus massoniana.

Based on the 3-year investigation on growth of half-sib progenies from 162 families of 12-year-old seed orchards of Pinus massoniana in Zhangping Wuyi National Forest Farm and Hua’an Xipi Forest Farm. The genetic variances and the heritabilities of families at different age were calculated, and the genetic gain and selection efficiency were estimated. The 25 selected families with fast growth had average tree height of 12.6 m, average DBH of 16.9 cm and average individual volume of 0.135 8 m3, and their genetic gain was 3.8 %, 14.4 %,27.5 %, respectively. The excellent families were used to select elite trees,167 individuals, with average height of 14 m, average DBH of 22.8 cm and average individual volume of 0.257 1 m3, the genetic gain was estimated at 7.1 %, 15.7 % and 43.5 %, respectively.