Variation and genetic parameters of axial resin canal features in clones and families of Pinus radiata

2021

English

Resin canal features are associated with significant economic losses to appearance grade Pinus radiata timber. This study investigated the variation in resin canal features for young, 2-year-old, P. radiata. Axial resin canal size, density and relative cross-sectional area were determined in twenty families and ten clones from images of microtomed sections, scanned with polarised light to highlight resin canals. Axial resin canal size was generally homogenous with a mean value estimate of 0.02 mm2, and a coefficient of variation of ~10%. Estimated mean values for axial resin canal density and relative area were more variable (coefficients of variation ~30%) and lower for clones (0.69 canals/mm2 and 1.13%, respectively) than for families (0.90 canals/mm2 and 1.53%, respectively). Narrow-sense heritability (h2) estimates of the studied axial resin canal features in radiata pine at age 2-years-old were ~0.30. Modulus of elasticity (MoE) and longitudinal shrinkage were moderately correlated with axial resin canal density and relative area, while basic density and volumetric shrinkage were independent of axial resin canal features. The study indicated that there could be potential for breeding P. radiata for resin canal features, with the aim to improve the grade yields of appearance grade products.

Govina, J. K.; Apiolaza, L. A.; Altaner, C. M.