selection for intramuscular fat in Duroc swine using real-time ultrasound. II. Genetic parameters and trends. J. Anim. Sci., 88: 69-79. Suzuki K., Irie M., Kadowaki H., Shibata T., Kumagai M., Nishida A. (2005). Genetic parameter estimates of meat quality traits in Duroc pigs selected for average daily gain, longissimus muscle area, backfat thickness, and intramuscular fat content. J. Anim Sci., 83: 2058-2065. Suzuki K., Ishida M., Kadowaki H., Shibata T., Uchida H., Nishida A. (2006). Geneticcorrelations among fatty acid compositions in different sites of fat tissues
References BALOCCHI, C., F. BRIDGWATER, B. ZOBEL and S. JAHROMI (1993): Age trends in genetic parameters for tree height in a nonselected population of loblolly pine. Forest Science 39: 231-251. BOLDMAN, K. G., L. A. KRIESE, L. D. VAN VLECK, C. P. VAN TASSELL and S. D. KACHMAN (1995): A manual for use MTDFReml. A set of programs to obtain estimates of variances and covariances. U.S. Department of Agriculture, Agriculturical Research Service BURDON, R. D. (1977): Geneticcorrelation as a concept for studying genotype-environment interaction in forest tree breeding
on the structure of breeding populations. Silvae Genet. 33: 186-198. BRIDGWATER, F. E. and R. W. STONECYPHER (1978): Genotype x environment interaction: Implications in tree breeding. In: Proc. Of the 5th North American Forest Biology Workshop, University of Florida, Gainesville, March 13-15, 1978: 46-63. BURDON, R. D. (1977): Geneticcorrelation as a concept for studying genotype-environment interaction in forest tree breeding. Silvae Genet. 26: 168-175. BURDON, R. D. and C. B. LOW (1992): Genetic survey of Pinus radiata. 6: Wood properties: variation
This study considered the degree of genetic variation for diameter (DBH), basic density (BD), predicted pulp yield (PPY), fibre length (FL), microfibril angle (MFA) and cellulose content (CC) amongst eight subraces of Eucalyptus globulus growing in a field trial in NW Tasmania. There were significant subrace effects for BD, FL and CC. This variation affected the relative profitability of the subraces for pulp production. On average, the most profitable subraces (on NPV/ha over the base population mean) were Strzelecki Ranges ($862.04), Western Otways ($657.80) and Strzelecki Foothills ($576.81). The genetic control (heritability) of variation in DBH, FL and MFA was moderate (0.15 < h2< 0.27), while control for BD, PPY and CC was high (h2> 0.40). Genetic correlations between growth and wood properties were not statistically significant, except for DBHMFA (-0.86). Most genetic correlations amongst wood properties were outside the parametric space (< -1 or >1), but there were significant correlations between BDMFA (-0.70) and PPY-CC (0.82). The empirical response to selection on an index based on a pulp wood objective (which included volume and basic density) resulted in a gain of 4.3% for DBH, 7.9% for BD and marginal changes for all other traits, with a net impact in profit of $1,270/ha. However, future profit calculations will need to consider the effect of FL, MFA and CC on the economics of wood processing to fully evaluate the economic impact of breeding.
Cordia alliodora (Ruiz & Pav.) Oken (Boraginaceae) is a tropical timber tree of great economic value that occurs in Latin America and through most of the Caribbean. Genetic variation in growth, form and survival of eight Central America provenances - five from a dry zone and three from a wet zone - were studied five and 23 years after establishment in the state of São Paulo, Brazil. Significant differences between dry and wet zone provenances were detected for diameter at breast height (d.b.h.), stem form and survival and between provenances within these zones for height, d.b.h., volume and survival. Provenances from the dry zone had higher growth rates than those from the wet zone. Genetic correlations among ages for these traits were positive but not significant, while ranking of provenances based on growth and survival changed significantly from five to 23 years of age, indicating that measuring traits at five years of age may not be a good predictor of the same traits at 23 years of age. Genetic correlations on growth traits measured at the same age were large and significant, suggesting substantial gains could be made through indirect trait selection. At 23 years of age the La Fortuna provenance performed best for all traits, while Nueva Guinea performed worst for growth traits and survival and Tres Piedras for stem form. The species’ poor growth compared to that of other tropical tree species at the same experimental site suggests that C. alliodora is not the best silvicultural option for the Luiz Antonio region.
Calycophyllum spruceanum (Benth.) Hook. f. ex K. Shum. is an important timber-tree species in the Peruvian Amazon Basin. As farmers and industry often use wood from young trees, it is important to investigate variation in juvenile wood properties in this species. A provenance/progeny test was established to evaluate genetic variation in growth and wood properties of young trees, the strength of their genetic control as well as their interrelationships both at the genetic and the phenotypic level in different planting zones. In this paper, results are presented for tree height and stem diameter (near ground level) at 16, 28 and 39 months; and stem diameter and basic density of the wood at breast height at 39 months. Significant variation due to provenances and especially due to families within provenances was found in growth and wood density. Phenotypic and genetic correlations indicated that larger trees tended to have denser wood. Wood density had higher heritability than height and diameter; and genetic control over height, diameter and density was generally highest in the planting zone where trees grew most rapidly.
): Study of early selection in tree breeding. 2. Advantage of early selection through shortening the breeding cycle. Silvae Genet. 48(2): 78-83. WU, H. X., YEH, F. C., DHIR, N. K., PHARIS, R. P. and DANCIK, B. P. (1997): Genotype by environment interaction and geneticcorrelation of greenhouse and field performance in Pinus contorta ssp. latifolia. Silvae Genet. 46: 170-175. ZAS, R. and FERNÁNDEZ-LÓPEZ, J.: Juvenile genetic parameters and genotypic stability of Pinus pinaster Ait. open-pollinated families under different water and nutrient regimes. For. Sci. (under
Fifty-one full-sib families were created using 11 parents in a silver fir seed orchard and a half-diallel mating design. The seeds of control-pollinated families were sown in a nursery in autumn 2007. Growth and branches traits were measured during nursery testing, and genetic parameters were estimated at the ages of 3, 4, 5, and 6 years. The additive and dominance genetic variances were major sources of genetic variance. Dominance variance was greater than additive variance at these early ages for all traits. However, the ratio of SCA/GCA variance decreased from 23 to 14 for total height and from 36 to 19 for root collar diameter. Broadsense family heritability is higher than individual heritability. Height and root collar diameter are the most heritable traits in silver fir. The time trend of the five heritability estimates for total height increased with age. Significant trait-trait genetic correlations were obtained. Age-age genetic correlations were very high, and they displayed increasing trends with age. The selection of the most valuable parents and most valuable individuals within the best families could maximise genetic gain in the second breeding generation of silver fir.
standardised and easy measurement of plant functional traits worldwide. Aust J Bot 51: 335. CORRIVEAU, A., J. BEAULIEU and G. DAOUST (1991): Heritability and geneticcorrelations of wood characters of Upper Ottawa Valley white spruce populations grown in Quebec. For Chron 67: 698-705. CORRIVEAU, A., J. BEAULIEU and F. MOTHE (1987): Wood density of natural white spruce populations in Quebec. Can J For Res 17: 675-682. DUCHESNE I. and S. Y. S. ZHANG (2004): Variation in tree growth, wood density, and pulp fiber properties of 35 white spruce (Picea glauca (Moench) Voss
References ABBOTT, J. K. and E. I. SVENSSON (2010): Morph-specific variation in intersexual geneticcorrelations in an intraspecific mimicry system. Evolutionary Ecology Research 12: 105-118. BAGCHI, S. K. (1995): Selection differential and predicted genetic gain in Tectona grandis. The Indian Forester 121(6): 482-490. BALL, J. B., D. PANDEY and S. HIRAI (2000): Global overview of teak plantations. In: „Site, technology and productivity of teak plantations“. FORSPA Publication N°24/2000, TEAKNET Publication N° 3, 11-33. BEKKER, C., W. RANCE and O. MONTEUUIS (2004