Diego Tyszka Martinez

PHENOTYPIC MODELS OF COMPETITION FOR Pinus taeda L GENETIC PARAMETERS ESTIMATION

The objective of this study was to evaluate the efficiency of the phenotypic models of competition, through spatial analysis in the genetic evaluation of Pinus taeda L progenies. For this, four competition covariates were used to adjust the phenotypic values in a P. taeda progeny test installed in four different locations in the state of Santa Catarina. The test was implemented in randomized block design, with seven repetitions, linear plots containing six plants per plot in 2.5 m x 2.0 m spacing. The test installed in sites A, B, and D present 63 families and site C 53 families. At nine years old, the diameter at the breast height was measured for all individuals. The presence or absence of competition was based on the residual autocorrelation coefficients, which had its significance tested by the Durbin-Watson test. In general, the use of covariates corrected the competition effect. The variances among and within plots, as well as the residual variation coefficient, were reduced. The classification by the genetic effect of the individuals in the progeny test was extremely altered for this data set with and without the use of covariates for sites A and D, as well as the genotype x environment interaction. The use of these two tools is of great importance in the analysis of data in P. taeda progeny tests, since the effects of competition can lead to mistakes in the selection of individuals and in the definition of improvement zones. MODELOS FENOTÍPICOS DE CONCORRÊNCIA PARA Pinus taeda L ESTIMAÇÃO DE PARÂMETROS GENÉTICOS RESUMO: O objetivo foi avaliar a eficiência dos modelos fenotípicos de competição, via análise espacial, na avaliação genética de testes de progênies de Pinus taeda L. Para isso foram utilizadas quatro covariáveis de competição para ajuste dos valores fenotípicos em um teste de progênies de P. taeda plantado em quatro diferentes locais no estado de Santa Catarina. O teste foi implantado em delineamento de blocos casualizados, com sete repetições, parcelas lineares de seis plantas e espaçamento de 2,5 m x 2,0 m. O teste instalado nos locais A, B e D possuem 63 famílias e no local C 53 famílias. Aos nove anos de idade foi efetuada a mensuração da variável diâmetro à altura do peito de todos os indivíduos. A presença ou não da competição foi baseada nos coeficientes de autocorrelação residual, que teve sua significância testada pelo teste de Durbin-Watson. No geral, o uso de covariáveis corrigiu o efeito da competição e as variâncias entre e dentro de parcela e o coeficiente de variação residual foram reduzidos. A análise espacial foi apropriada para validar a eficiência das covariáveis. A classificação pelo efeito genético dos indivíduos no teste de progênies foi extremamente alterada para o conjunto de dados com e sem o uso de covariáveis para os locais A e D, assim como a interação genótipo x ambiente. O uso dessas duas ferramentas é de suma importância na análise de dados em testes de progênies de P. taeda, pois os efeitos de competição podem conduzir a erros na seleção de indivíduos e na definição de zonas de melhoramento.

Genetic diversity of Cedrela fissilis (Vell.): insights on conservation and production

The objective of this study was to determine selection criteria for the genetic conservation of, and growth improvement in Cedrela fissilis using a progeny test composed of 48 C. fissilis families planted with Pinus taeda in Rio Negrinho Municipality, Santa Catarina State, Brazil. Genetic parameters were estimated using the restricted maximum likelihood method, and early predictions of genetic gains were estimated using best linear unbiased predictions and a multi-effects index. Deviance analyses indicated that the families originated from a single population, and there were significant differences in survival, collar diameter and height among progeny. Stem bifurcation, number of sprouts per stump, damage caused by Hypsipyla grandella and frost damage did not differ. A seedling seed orchard was proposed to produce seeds for genetic conservation aimed at forest restoration in the Brazilian “Legal Reserve”. It is estimated that these seeds will have a genetic gain of 2% for survival and a population size of 78 through the selection based on the progeny’s additive values. In order to produce genetically improved seeds through a clonal seed orchard, a family selection based on independent elimination levels was proposed, using additive genetic values for survival and a multieffect index within plots for collar diameter. In this case, 15 genotypes were selected, with a predicted gain of 4% in survival and 18% in collar diameter. The genetic variability found enables the use of the progeny test as an active germplasm bank, combining genetic conservation and sustainability of C. fissilis.

Capacidade produtiva de Tectona grandis L.f no Sudoeste de Mato Grosso

The knowledge of the site is necessary to understand the production and forest management. The objective of this study was to determine the productive capacity of Teak in southwestern Mato Grosso State, through the analysis of site index curves, to forest harvesting. The data were collected in permanent plots and the stem analysis of 32 dominant trees of two stands, 33 and 34 years old. Eight site index models were adjusted and the selection criteria followed the lowest standard deviation, the highest adjusted coefficient of determination, F test value and the absence of trends in the graphical analysis of the residuals. The site index curves were prepared by the method of the guide curve. Soil samples were collected for physical analysis and macronutrients. The model presented by Hoerl had the best fit and it was found that the database follows an anamorphic pattern, thus, the growing trend is the same between the curves. Four site index curves were generated in an age-index of 30 years and three productivity classes of Teak were established. The soil characteristics of the region are favorable to the cultivation of Teak and the curves illustrate the productive potential for the species.