@article{sykes_li_isik_kadla_chang_2006, title={Genetic variation and genotype by environment interactions of juvenile wood chemical properties in Pinus taeda L.}, volume={63}, ISSN={["1286-4560"]}, DOI={10.1051/forest:2006073}, abstractNote={Genetic variation and genotype by environment interaction (G×E) were studied in several juvenile wood traits of 11 year-old loblolly pine trees (Pinus taeda L.). Wafer thin (200 µm) samples from juvenile (ring 3) and transition (ring 8) wood of 12 mm increment cores were analyzed. Transition wood had higher α-cellulose content (46.1%), longer fiber (1.98 mm), and higher coarseness (0.34), but lower lignin (29.7%) than juvenile wood (cellulose 40.9%, fiber length 1.4 mm, coarseness 0.28 and lignin 30.3%). General combining ability variance for the traits explained 2% to 10% of the total variance, whereas the specific combining ability variance was negligible, except for α-cellulose content in transition wood (2%). Specific combining ability by site interaction variance explained from 5% (fiber length) to 37% (lignin) of the total variance. Weak individual-tree heritabilities were found for all the traits, except coarseness, which was moderately high in both juvenile (0.39) and transition wood (0.30). Full-sib and half-sib family heritabilities of traits ranged 0.29 to 0.72. Genetic correlations of wood quality traits with volume and stem straightness were weak, while favorable genetic correlations of lignin with cellulose, coarseness and fiber length were observed. Implications on forest tree improvement programs were discussed. heritability / genetic correlation / α-cellulose / coarseness / lignin}, number={8}, journal={ANNALS OF FOREST SCIENCE}, publisher={EDP Sciences}, author={Sykes, Robert and Li, Bailian and Isik, Fikret and Kadla, John and Chang, H. -M.}, year={2006}, month={Dec}, pages={897–904} }
 @article{sykes_li_hodge_goldfarb_kadla_chang_2005, title={Prediction of loblolly pine wood properties using transmittance near-infrared spectroscopy}, volume={35}, ISSN={["1208-6037"]}, DOI={10.1139/X05-161}, abstractNote={ Near-infrared (NIR) spectroscopy is a rapid nondestructive technique that has been used to characterize chemical and physical properties of a wide range of materials. In this study, transmittance NIR spectra from thin wood wafers cut from increment cores were used to develop calibration models for the estimation of α-cellulose content, average fiber length, fiber coarseness, and lignin content in the laboratory. Eleven-year-old trees from two sites were sampled using 12-mm increment cores. Earlywood and latewood of ring 3 and ring 8 from these samples were analyzed in the laboratory using microanalytical methods for α-cellulose content, average fiber length, fiber coarseness, and lignin content. NIR calibrations and laboratory measurements based on one site were generally reliable, with coefficients of determination (R2) ranging from 0.54 to 0.88 for average fiber length and α-cellulose content, respectively. Predicting ring 8 properties using ring 3 calibration equations showed potential for predicting α-cellulose content and fiber coarseness, with R2 values of approximately 0.60, indicating the potential for early selection. Predicting the wood properties using the calibration equations from one site to predict another showed moderate success for α-cellulose content (R2 = 0.64) and fiber coarseness (R2 = 0.63), but predictions for fiber length were relatively poor (R2 = 0.43). Prediction of lignin content using transmittance NIR spectroscopy was not as reliable in this study, partially because of low variation in lignin content in these wood samples and large errors in measuring lignin content in the laboratory. }, number={10}, journal={CANADIAN JOURNAL OF FOREST RESEARCH}, author={Sykes, R and Li, BL and Hodge, G and Goldfarb, B and Kadla, J and Chang, HM}, year={2005}, month={Oct}, pages={2423–2431} }
 @article{sykes_isik_li_kadla_chang_2004, title={Genetic variation in physiochemical wood properties in loblolly pine (Pinus taeda L.)}, volume={2}, number={12}, journal={TAPPI Journal}, author={Sykes, R. and Isik, F. and Li, B. and Kadla, J. and Chang, H.-M.}, year={2004}, pages={3–8} }
 @article{sykes_isik_li_kadla_chang_2003, title={Genetic variation of juvenile wood properties in a loblolly pine progeny test}, volume={2}, number={12}, journal={TAPPI Journal}, author={Sykes, R. and Isik, F. and Li, B. L. and Kadla, J. and Chang, H. M.}, year={2003}, pages={08-} }
 @article{sykes_isik_li_kadla_chang_2003, title={Genetic variation of juvenile wood properties in loblolly pine diallel test}, volume={27}, journal={Proc. 27th Biennial Southern Forest Tree Improvement Conference}, author={Sykes, R. and Isik, F. and Li, B. and Kadla, J. and Chang, H-M.}, year={2003}, pages={27} }