Genetic Variation and Index Selection of Growth and Resin Yield of 20-year Half-sib Families of Pinus massoniana

In July 2011, determinations were carried out on height, DBH and volume of 20-year Pinus massoniana of 48 half-sib families and 5 controls in Nanning, Guangxi Zhuang Autonomous Region, and from August to December of the same year, resin tapping was implemented. Analysis demonstrated that height, DBH, volume and resin yield had significant genetic differences among families, with variable coefficient of 5.28%, 8.33%, 12.41% and 4.71%, and heritability of 0.524, 0.607, 0.585 and 0.468. Correlation analysis on different traits indicated that it had significant phenotypic and genetic correlation among growth and resin yield. Improvement of DBH had obvious effect on resin yield, indicating significant positive correlation between them. Index equation with growth traits and resin yield calculated 10 superior families. Their mean genetic gain of resin yield was 23.92%.