In long term, to discover the genes responsible for wood production, genetic control of wood specific gravity (WSG) in Pinus brutia Ten. (Turkish red pine) open pollinated Ceyhan progeny trial, which was established with the seeds collected from 168 clones originated from six clonal Turkish red pine seed orchards was studied. Wood samples were taken by destructive sampling during the rouging of this trial at the age of seven. Specifically / (1) to examine the magnitude of family differences and its components for wood specific gravity (WSG) and growth traits (height, diameter and stem volume) / (2) to determine WSG inheritance and its genetic correlation with growth traits / and (3) to estimate breeding values of 168 families for the WSG and to predict genetic gain if selection is based on phenotypic, rouged and genotypic seed orchard by reselecting the best parents with respect to WSG. Differences among the 168 families for mean WSG was large (ranged from 0.35 to 0.44), as indicated by high individual (0.42+0.07) and family mean (0.55+0.03) heritabilities. Family differences and high heritabilities were also observed for all growth traits. Genetic correlations between WSG and growth traits were statistically insignificant (near zero), while low and insignificant negative phenotypic correlations among the same traits were observed. Realized genetic gain for single trait selection at age seven was insignificant (0.37 %) for WSG and 8.4 % for stem volume in phenotypic seed orchards. Average genetic gain in breeding zone after roguing, by leaving the best 20 clones in each seed orchard, reached 1.7 % for WSG and 16.1 % for stem volume. Genetic gain (relative to controls) at the age of seven obtained from the first generation genotypic seed orchards consisting the best 30 clones was estimated 5.2 % for WSG and 35 % for stem volume. Multi-trait selection was also proposed in this study for the same traits. Selection of best 10 families for the highest WSG and stem volume breeding values produce 5.6 % genetic gain for WSG and 27.7 % genetic gain for stem volume. For the future, the 168 families with known phenotypic and genotypic values regarding to WSG will be screened for the genes responsible for wood production.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This study had as objective to estimate genetic parameters and genetic and phenotypic progress for growing characteristics at pre and post weaning for an Aberdeen Angus cattle breed. The covariance components were obtained by the REML using an animal model. In the article 01 they were analyzed the characteristics birth weight (PN), average daily gain from birth to weaning (GMDND), weaning weight adjusted to 205 days of age (P205) and visual scores (EVs) of conformation (C), precocity (P), musculature (M) and size (T), at the pre weaning phase, from 23,176 animals born between the years 1994 and 2004. The direct and maternal heritabilities were: 0.27 and 0.11, 0.26 and 0.21, 0.24 and 0.07, 0.15 and 0.17, 0.12 and 0.08, 0.12 and 0.10, and 0.19 and 0.09, respectively to PN, GMDND, P205, C, P, M, and T. The genetic correlations between GMDND and EVs ranged from 0.55 to 0.66 and for the EVs in between themselves, from 0.50 to 0.92. The genetic trends for PN, GMDND, P205 (g/year) and for C, P, M e T (points/year) were: 17.5, 1.1, 220.9, 0.0046, 0.003, 0.0044, and 0.0063 and the phenotypic were 29.8, -3.3, 467.9, 0.0037, -0.0044, 0.0153, and -0.0163 respectively. The direct heritabilities suggest that it can be possible to get genetic gain by selection in this population, although for the EVs, this must be expected in low proportions. The genetic correlations between GMDND and EVs shows that selection for GMDND promotes improvement in EVs and vice-versa, suggesting that selection index combining these characteristics can be an efficient alternative selection method. The positive genetic trends indicate that it is occurring genetic progress; however the phenotypic, negative, for same characteristics suggest the necessity that to improve the environmental conditions to permit the expression of the genotype. In article 02 it were analyzed the post weaning characteristics yearling weight adjusted to 550 days of age (P550), average daily gain from weaning to yearling (GMDDS), and the EVs, according to Article 01. In post weaning phase the data were composed by observations on 28,349 animals, born from 1993 to 2003. The direct heritabilities estimated were: 0.23, 0.16 , 0.13, 0.11, 0.16 and 0.13, to P550, GMDDS, C, P, M and T, respectively. The genetic correlations between GMDDS and the EVs range from 0.27 a 0.43 and between the EVs ranged from 0.01 a 0.92. The genetic trends estimated for P550 and GMDDS (g/year) and for C, P, M, and T (points/year) were: 193.2; 0.1, 0.0054, 0.0035, 0.0057, and 0.0026, respectively. The phenotypic trends for the same characteristics were: 3,868, -2.2, 0.0189, -0.0013, 0.0217 and -0.0016, respectively. The direct heritabilities estimated suggest to be possible to get genetic gain by selection in this population. The genetic correlations between GMDDS and the EVs suggest that the selection for GMDDS promote improvement in EVs and vice-versa; for the EVs between themselves the correlations were height between C, P and M (0.79 to 0.92) and low between these and T (0.01 to 0.30). The genetic trends indicate that the selection is promoting, although low, genetic progress; however the phenotypic, negative, for same characteristics suggest that more attention must be given to the environmental conditions to permit the expression of the genotype. / Este estudo teve como objetivo estimar parâmetros genéticos e o progresso genético para as características de desempenho na pré e na pós-desmama, para uma população bovina da raça Aberdeen Angus. Os componentes de (co)variância foram estimados por REML, utilizando modelo animal. No artigo 01 foram analisadas as características peso ao nascer (PN), ganho médio diário do nascimento a desmama (GMDND), peso a desmama ajustado para 205 dias (P205) e os escores visuais (EVs) conformação (C), precocidade (P), musculatura (M) e tamanho (T), na fase pré-desmama, de 23.176 animais, nascidos entre os anos de 1994 e 2004. As herdabilidades diretas e maternas foram: 0,27 e 0,11, 0,26 e 0,21, 0,24 e 0,07, 0,15 e 0,17, 0,12 e 0,08, 0,12 e 0,10 e 0,19 e 0,09, para PN, GMDND, P205, C, P, M e T, respectivamente. As correlações genéticas entre o GMDND e os EVs variaram de 0,55 a 0,66, e para os escores visuais entre si de 0,50 a 0,92. As tendências genéticas para PN, GMDND, P205 (g/ano) e para C, P, M e T (pontos/ano) foram 17,5; 1,1; 220,9; 0,0046; 0,003; 0,0044 e 0,0063 e as fenotípicas foram 29,8; -3,3; 467,9; 0,0037; -0,0044; 0,0153 e -0,0163, respectivamente. As herdabilidades diretas sugerem ser possível obter ganho genético através da seleção nesta população, embora, para os EVs, esse deve ser esperado em pequena proporção. As correlações genéticas entre GMDND e os EVs indicam que a seleção para GMDND promove melhoria nos EVs e vice versa, sugerindo que a adoção de índices de seleção combinando essas características pode ser uma alternativa eficiente de seleção. As tendências genéticas, positivas, indicam estar havendo progresso genético; porém, as fenotípicas, negativas para algumas características, sugerem a necessidade de melhorias nas condições ambientais para viabilizar a expressão do genótipo. No artigo 02 foram analisadas as características peso ao sobreano ajustado para 550 dias de idade (P550), ganho médio diário de peso da desmama ao sobreano (GMDDS) e os EVs conforme o Artigo 01. Na fase pós-desmama o banco de dados continha registros de 28.349 animais, nascidos entre os anos de 1993 e 2003. As estimativas de herdabilidade foram: 0,23; 0,16; 0,13; 0,11; 0,16 e 0,13, para P550, GMDDS, C, P, M e T, respectivamente. As correlações genéticas entre o GMDDS e os EVs variaram de 0,27 a 0,43 e para os escores visuais entre si de 0,01 a 0,92. As tendências genéticas estimadas para P550 e GMDDS (g/ano), e para C, P, M e T (pontos/ano) foram: 193,2; 0,1; 0,0054; 0,0035; 0,0057, e 0,0026, respectivamente. As tendências fenotípicas para as mesmas características foram: 3,868; -2,2; 0,0189; -0,0013; 0,0217 e -0,0016, respectivamente. As herdabilidades diretas estimadas sugerem ser possível obter ganho genético através da seleção nesta população. As correlações genéticas entre GMDDS e os EVs sugerem que a seleção para GMDDS promove melhoria nos EVs e vice versa; para os EVs entre si foram altas as correlações entre C, P e M (0,79 a 0,92) e baixas entre estes e T (0,01 a 0,30). As tendências genéticas demonstram que a seleção praticada está promovendo, embora pequeno, ganho genético; entretanto as fenotípicas, negativas para algumas características, indicam que deve ser dada mais atenção ao ambiente visando favorecer a expressão do genótipo.