PRELIMINARY GENETIC PARAMETER ESTIMATES FOR SOME WOOD QUALITY TRAITS OF PINUS-CARIBAEA VAR HONDURENSIS IN QUEENSLAND, AUSTRALIA

Diametral increment cores were sampled from 27 open pollinated families to study juvenile wood characteristics in an 11 year old progeny trial of Pinus caribaea var. hondurensis planted at two locations. Heritabilities and phenotypic and genetic correlations were estimated for radial and height growth, stem straightness, and wood quality traits. Estimates of individual tree narrow-sense heritability for latewood percentage, compression wood percentage and basic density were consistent with those reported previously for Pinus caribaea and the southern pines, with values of 0.55, 0.02 and 0.62 respectively. Spiral grain angles at growth rings 3, 5, 7 and 9 were measured using positive and negative signs to indicate direction of spiral for right hand and left hand spirals respectively. Heritabilities and phenotypic and genetic correlations were estimated both using and ignoring sign. Heritability estimates increased from 0.12 for ring 3 to 0.46 for ring 9 while those for radial standard deviation and mean absolute spiral grain were 0.24 and 0.28 respectively. Heritability estimates for growth and straightness were consistent with those reported previously. Genetic correlations were relatively imprecise, but suggest an adverse correlation of radial growth with percent latewood and basic density. The results of subsequent studies are needed to clarify the relationship between growth and juvenile wood quality of Pinus caribaea var. hondurensis in Queensland and to extend this work to mature wood as material from older trials becomes available.