Antonio Rioyei Higa

Selection and genetic gain in rubber tree (Hevea) populations using a mixed mating system

The components of genetic variation and genetic gain obtained with three selection methods - individual, combined and multi-effect index selection - were compared in rubber tree [Hevea brasiliensis (Willd. ex Adr. de Juss.) Muell. Arg.] progenies. The rubber tree is a cross pollinating species with a mixed reproductive system in which the self pollination rate is 22%. Twenty-two half sib progenies were planted at experimental stations at Pindorama, Votuporanga and Jau, in Sao Paulo State, using a randomized and complete block design, with five replications and ten plants per plot. Dry rubber production was assessed when the plants were three years old. Based on the genetic variability of the populations, Pindorama was the best environment for the expression of variability. At the individual level, heritability was seriously affected when random progenies from an open pollinating population were considered as half sib progenies. Considerable overestimation of genetic gains occurred during individual, combined and multi-effect index selection when the rubber tree reproductive system was not considered as mixed. Selection based on the multi-effect index maximizes genetic progress and should be used more in rubber tree breeding programs.

Efeitos de substratos e recipientes utilizados na produção das mudas sobre a arquitetura do sistema radicular de árvores de cácia-negra

RESUMO – O objetivo deste trabalho foi caracterizar a arquitetura do sistema radicular de arvores de acacianegra (Acacia mearnsii) aos tres anos apos o plantio, em razao da combinacao de oito tipos de recipientes e seis misturas de substratos usados na producao das mudas, levando-se em consideracao atributos quimicos e fisicos do solo. As arvores foram plantadas no municipio de Cristal (RS), em solo Podzolico Vermelho Escuro, que apresentou alta densidade, baixo pH e excesso de aluminio. O tratamento que teve maior desenvolvimento radicular foi o fertil-pot, com substrato constituido por solo adubado, que diferiu estatisticamente dos tratamentos tubete redondo, com solo adubado + casca de acacia esgotada + vermiculita; paper pot, com solo adubado e laminado acondicionado em caixas de madeira, com solo adubado. O desenvolvimento e arquitetura das raizes no campo foram afetado pelo recipiente, mas nao pelo substrato utilizado na fase de viveiro.

INTERAÇÃO GENÓTIPOS X AMBIENTES PARA PRODUTIVIDADE DE CLONES DE Eucalyptus L'Hér. NO ESTADO DO RIO GRANDE DO SUL

Este trabalho objetivou estudar a interacao genotipos em ambientes de clones de Eucalyptus em quatro ambientes do Estado do Rio Grande do Sul. Os ensaios foram conduzidos nas areas da empresa CMPC Celulose Riograndense, nos Municipios de Minas do Leao (Horto Florestal Cambara), Encruzilhada do Sul (Horto Florestal Capivara), Dom Feliciano (Horto Florestal Fortaleza) e Vila Nova do Sul (Horto Florestal Sao Joao). No ano 2007, foi implantada uma rede de testes clonais com 864 clones de Eucalyptus, pertencentes a 37 especies e hibridos. Aos 3 anos de idade, foram mensurados o diâmetro a altura do peito (dap) e a altura total (Ht) das arvores dos experimentos. O incremento medio anual (IMA) foi calculado de acordo com o volume individual por clone e o estande de plantas por hectare na idade de avaliacao do teste clonal. Os resultados da correlacao genotipica entre os ambientes variaram de 0,39 a 0,56, demonstrando que ocorreu interacao genotipos x ambientes significativa dos caracteres avaliados. Esses resultados indicam que e necessario selecionar clones especificos, nas combinacoes de ambientes com baixa correlacao genetica entre si. Ocorreu baixa correcao genetica entre os ambientes Cambara x Capivara; Cambara x Sao Joao; Capivara x Fortaleza; Capivara x Sao Joao; e Fortaleza x Sao Joao. Dessa maneira, para este estudo foram necessarias tres unidades de manejo para minimizar os efeitos da interacao genotipos x ambientes. Incluindo a selecao por estabilidade, adaptabilidade e os dois atributos simultaneamente, ocorreu mudanca de clones e de posicao entre os clones no ordenamento de selecao. Com a selecao simultânea por estabilidade e adaptabilidade (MHPRVG), os ganhos aumentaram em comparacao com a selecao pelos valores genotipicos preditos entre os ambientes, principalmente, e houve incremento dos ganhos em relacao a testemunha comercial. Por exemplo, os cinco melhores clones pelo criterio MHPRVG apresentaram-se 56% superiores a testemunha comercial para a caracteristica produtividade em volume.

Adaptabilidade de híbridos multiespécies de Eucalyptus ao Estado do Rio Grande do Sul

RESUMO – Neste trabalho, objetivou-se estudar a adaptabilidade de hibridos multiespecies de Eucalyptus em quatro ambientes do Estado do Rio Grande do Sul. Os ensaios foram realizados nas areas da empresa CMPC Celulose Riograndense, nos Municipios de Minas do Leao (Horto Florestal Cambara), Encruzilhada do Sul (Horto Florestal Capivara), Dom Feliciano (Horto Florestal Fortaleza) e Vila Nova do Sul (Horto Florestal Sao Joao). No ano 2007 foi implantada uma rede de testes clonais com 146 clones de Eucalyptus, pertencentes a 34 diferentes especies e, ou hibridos, em delineamento de blocos ao acaso com 30 repeticoes e uma planta por parcela (Single Tree Plot). Aos 3 anos de idade, foram mensurados o diâmetro a altura do peito (dap) e a altura total (Ht) das arvores dos experimentos. O incremento medio anual (IMA) foi calculado de acordo com o volume individual por clone e o estande de plantas no hectare na idade de avaliacao do teste clonal. Concluiu-se que em um programa de melhoramento do eucalipto a analise simultânea de produtividade, estabilidade e adaptabilidade deve ser preferida em relacao ao simples ordenamento de valores genotipicos. Na selecao simultânea, destacaram-se entre os melhores materiais geneticos do ordenamento, hibridos do tipo “three-way cross”, formados por tres diferentes especies de Eucalyptus. Os hibridos mais promissores para a geracao de clones superiores foram E. urophylla x (E. camaldulensis x E. grandis), E. grandis x (E. urophylla x E. grandis), E. saligna x (E. grandis x E. urophylla) e E. grandis x E. kirtoniana (E. robusta x E. tereticornis) e E. grandis x E. urophylla. Palavras chave: Eucalyptus spp.; Performance relativa; Ganhos preditos; Estabilidade; Clones. ADAPTABILITY FOR EUCALYPTUS MULTI SPECIES HYBRIDS IN THE STATE OF RIO GRANDE DO SUL

Fitossociologia dos estratos arbóreo e de regeneração natural em um povoamento de acácia-negra ( Acacia mearnsii , De Wild.) na região da Floresta Estacional Semidecidual do Rio Grande do Sul.

This study analyzes the structure and floristic composition of the regeneration of native forest species under black-wattle plantation, established 16 years ago in a riparian area, and it verifies the possibility of the black-wattle be considered an invasive species of this environment. The tree stratum (circumference at breast height (CBH) ≥15 cm) was evaluated in 12 plots of 100 m2, established in four blocks. The natural regeneration stratum (0.3 m height to <15 cm CBH) was evaluated in two subplots of 9 m2, established in opposite vertexes of each plot. The tree stratum was composed by 26 species of 14 families and the natural regeneration stratum by 49 species of 23 families. The Shannon diversity index for species, considering all plots, was 2.60 and 3.06 to the tree and natural regeneration strata, respectively. The native species, Casearia sylvestris , Myrsine lorentziana and Zanthoxylum petiolare presented the larger importance value in the tree stratum and Faramea marginata , Myrsine lorentziana and Myrcia glabra the biggest density in the natural regeneration stratum. The ecological characteristics of the species found in several height strata indicated that the forest succession process is in evolution. The black-wattle did not regenerate in this area and the planted trees of this species are in the senescence phase. Only 100 tree/ha of black-wattle were found, which represents 4.5% of the original population. Thus, black-wattle is not an invasive species for this environment.

GENETIC GAIN FROM DIFFERENT SELECTION METHODS IN Eucalyptus macarthurii PROGENIES IN DIFFERENT ENVIRONMENTS

The aims of this research was to estimate genetic parameters of Eucalyptus macarthurii progenies and to predict genetic gain for different selection methods. In order to evaluate the gains, eleven progenies tests were studied. These tests were installed in 1997, in randomized blocks design, in two sites, with 5 replicates of five plants per plot. The progenies were evaluated, from the first to the eighth year, regarding the variable diameter at breast height (DBH). The genetic parameters were estimated using the mixed model procedure (REML/BLUP). The selection of the progenies for establishing a Clonal Seed Orchard was based on the analysis by location, joint analysis and on the harmonic mean of the relative performance of genotypic values (HMRPGV) with different selection intensities among and within families: three, four, five and six individuals per progeny with the selection of the top 30 individuals, taking into consideration the effective population size (N e ). The best age to carry out the selection was seven years old, however, early selection can be made from age two onwards. Each environment characteristics influenced progenies phenotypic expression, so the higher gains in balance with N e , were estimated with the selection of individuals for each site, and the selection of five or six individuals per progeny.

An index combining volume and Pilodyn penetration to study stability and adaptability of Eucalyptus multi-species hybrids in Rio Grande do Sul, Brazil

ABSTRACT This paper presents results from a study into the stability and adaptability of Eucalyptus multi-species hybrids in the state of Rio Grande do Sul, Brazil, using an index that includes volume growth and Pilodyn penetration. Clonal tests were established with 146 Eucalyptus clones from 34 different species and/or hybrids, in a randomised block design with 30 replications, and one plant per plot in four different sites. Diameter at breast height (dbh), tree total height (th), and Pilodyn penetration for indirect estimate of basic density were measured in trees at three years of age. An index (MAIweight) combining mean annual volume increment and Pilodyn penetration was calculated. In the analysis of MAIweight for each site, the best clones were from pure species (E. urophylla, E. grandis and E. saligna). In contrast, the evaluation of adaptability and stability between the four environments simultaneously showed that three-way cross and single cross hybrids ranked more highly: E. urophylla × (E. camaldulensis × E. grandis), E. grandis × (E. urophylla × E. grandis) and E. grandis × E. urophylla. This study demonstrates the importance of heterosis (hybrid vigour) to improving adaptability and stability. Genetic complementarity from crosses between different species was the principal process that produced the observed heterosis. While the pure species performed well in specific environments, the hybrids presented better broad adaptation to a range of environments. Breeding efforts should therefore account for these features when planning crosses and choosing sites for establishing trials.

SELEÇÃO PRECOCE DE PROGÊNIES DE Pinus radiata A Sphaeropsis sapinea

Sphaeropsis sapinea is an important pathogen for some Pinus radiata causing tip blight and death of trees, in commercial plantings. This study was developed to select Pinus radiata progenies resistant to the pathogen, for new plantings in Brazil. Seedlings tips of 16 Pinus radiata progenies were inoculated with three pathogen monosporic isolates of Sphaeropsis sapinea, under greenhouse conditions. Lesions length and tip blight degree were evaluated. Responses of progenies to the pathogen varied according to tested isolate. The results indicated that early selection methodology was adequate to select Pinus radiata progenies resistant against Sphaeropsis sapinea. Average heritability of the progenies varied according to tested isolate and the selection criterion used.

Utilisation of near infrared spectroscopy in Pinus taeda progeny tests located in southern Brazil.

Pinus taeda L. (loblolly pine) is one of the most important commercial timber species in the world. While the species is native to south eastern USA, it has been widely planted in southern Brazil where it is the most commonly planted exotic species. Interest exists in improving the wood quality of Brazilian grown loblolly pine and utilising near infrared (NIR) spectroscopy to assess wood properties. The successful application of NIR spectroscopy relies on the development of wood property calibrations with strong statistics which may be difficult when a population is of relatively young age and of limited genetic variation. In this study, the creation of calibrations for air-dry density, microfibril angle (MFA) and stiffness, based on samples from an 11-year-old progeny test located in the Rio Negrinho municipality of Santa Catarina, Brazil was explored. Untreated and math treated (first and second derivative and standard normal variate) NIR spectra that had been collected in 10 mm increments from the radial surface of 80 pith-to-bark wood strips were used to build the calibrations. The strongest calibrations overall were obtained using first derivative spectra and had coefficients of determination (R2) that ranged from 0.75 (density) to 0.92 (stiffness). Calibrations were tested on a separate test set and performed well with first derivative treated spectra giving the strongest predictions, r2 ranged from 0.73 (density) to 0.90 (stiffness). The strength of the predictions demonstrates that NIR can be utilised to estimate wood properties of loblolly pine progeny tests at a relatively young age.

AVALIAÇÃO DAS PROPRIEDADES DE PAINÉIS COMPENSADOS DE Melia azedarach L. PRODUZIDOS COM DIFERENTES GRAMATURAS E TEMPOS DE PRENSAGEM

Brazil is a major producer of plywood, where pine forests are the most used in this process, and much of this production is aimed at the furniture industry. Many species have been introduced in the country for this and other purposes, including the Melia azedarach, which still requires many technological studies for the best use of its wood. In this context, the objective of this research was to evaluate the feasibility of use of Melia azedarach for the production of plywood and the effect of the weight of adhesive and pressing time on the properties of the panels. 5 trees from an experimental planting located in Corupa, SC, were used, from which samples were collected for the determination of the density (COPANT 461/1972) and chemical properties (TAPPI 204:1997; 207: 1999; 280: 1999; 212:2002; 252:2002), and for obtaining the veneers. The panels were produced with dimensions of 500mm x 500mm x 10mm (5 veneers) according to a randomized block design in a factorial arrangement (3x2) with 3 weights (320 g/m2, 360 g/m2and 400 g/m2) and 2 pressing times (8 and 10 minutes), urea-formaldehyde adhesive, specific pressure of 1 MPa and temperature of 110 °C. The properties of the panels were evaluated from the static bending (EN: 310:2002) and resistance of the glue line to shearing (EN 314-1:2004 and EN 314-2:2002). The results indicated statistically significant difference between main effects: weight and pressing time only for the modulus of elasticity in the perpendicular direction, and the lack of significant differences between the means from the interaction of these two response variables. It was concluded that the species is technically feasible for the production of plywood, being able to maximize productivity and minimize production costs by the use of adhesive lighter weight and shorter pressing time.