Genotypic variation in the basic density, dynamic modulus of elasticity and tracheid traits of Pinus elliottii in three progeny trials in southern China

A firm understanding of the genetic relationships among wood properties is a prerequisite for breeding for higher wood quality in Pinus elliottii families. To examine and deal with such relationships, increment cores were sampled at breast height from 1260 trees in 42 open-pollinated families in three 27-year-old Slash pine progeny trials in southern China, and genetic variation, genotype-by-environment (G x E) interaction, genetic correlation and correlated response were investigated. The basic density (BD), dynamic modulus of elasticity (MOED) and tracheid traits were found to be under moderate to strong genetic control for the three locations combined, with individual narrow-sense and family mean heritability ranging from 0.28 to 0.44 and 0.52 to 0.69, respectively. Type B genetic correlation estimates indicated that the G x E interaction had a small-level influence on wood properties. Strong genetic correlations (r(g)) were found between BD and MOED at the three sites (r(g) = 0.46-0.85), and BD or MOE, showed moderate to strong correlations with most tracheid traits at specific localities. In tree breeding programs, one possible strategy would be to improve pulpwood quality and the strength of structural wood through selection for different wood quality traits.