NIR spectral heritability: a promising tool for wood breeders

Abstract

NIR spectroscopy has been widely used in tree-breeding programmes for selection because it is able to characterize large wood samplings rapidly and at relatively low cost. NIR spectra were recorded on various radial and longitudinal positions on the wood of 150 Eucalyptus trees. Each NIR spectrum used for analysis consisted of 280 absorption values following data reduction. The ratio between the genetic variance and phenotypic variance of the NIR absorbance values was calculated for each wavenumber producing the broad-sense NIR spectral heritability estimates. The variations in NIR spectra are thought to be related to variation in lignin and cellulose and hemicelluloses contents. The findings suggest that the variations of some specific ranges of the NIR spectra are controlled by genetic factors. Some ranges of the NIR spectra showed heritabilities greater than 50%. Thus, these variations in NIR spectra are thought to be related to variation in lignin, cellulose and hemicelluloses contents. The indirect estimates of broad-sense heritabilities from NIR spectra recorded on wood appear to be an efficient and promising way to evaluate the genetic control for many wood traits simultaneously.