Abstract Plantations made up of clones carry genetic uniformity that can compromise production. The use of multiclonal plantations is a possible solution. The objective of this study was to identify effects of competition on silvicultural performance of Eucalyptus spp. commercial clones. The experiment was carried out in a randomized block design with 12 eucalyptus clones, three replicates, and five plants per plot. Clones were evaluated for two competition types, intra- and intergenotypic, at 3 and 5 years of age. Competition parameters were estimated based on the analyses performed. Differences were found between the types of competition at both ages for mean annual increment and wood volume. Clones 8 and 9 stood out from the others in both intra- and intergenotypic competition. At 5 years of age, intergenotypic competition produced productivity gains of 13% in clones 8 and 9 and 4% overall considering wood volume and mean annual increment.

RESUMO A quinoa possui destaque devido à sua qualidade nutricional, baixo colesterol e ausência de glúten; no Brasil, os esforços em seu cultivo, nas diferentes regiões, estão relacionados principalmente ao melhoramento. O presente trabalho objetivou determinar os parâmetros genéticos e avaliar a produtividade de diferentes genótipos de quinoa com o propósito de detectar genótipos passíveis de seleção. O experimento foi realizado nos anos agrícolas de 2010/11 e 2011/12, caracterizando ambientes 1 e 2, respectivamente. Dentro do ambiente 1, realizou-se a avaliação de 61 genótipos, no ambiente 2, foram avaliados 31 genótipos. O delineamento experimental adotado foi o de blocos casualizados com duas repetições, cada parcela medindo 2,0 x 5,0 m (10 m²) sendo constituída de quatro linhas espaçadas de 0,45 m. Com os dados de produtividade, altura de plantas na maturação e ciclo, foram realizadas análise de variância, teste de média e estimado os parâmetros genéticos. Os genótipos N24 e N08 foram os únicos a superar a produtividade de outros 46 genótipos, apresentando valores de produtividade de 1.446,23 e 1.428,93 kg ha-1, com ciclo de 117 e 111 dias, respectivamente. Os valores de herdabilidade determinados demonstram a possibilidade de ganho genético com a seleção conjunta, envolvendo os dois ambientes.

ABSTRACT Quinoa has been gaining attention because of its nutritional quality, low cholesterol and lack of gluten; in Brazil, the cultivation efforts in the different regions are mainly related to breeding. This study aimed to determine the genetic parameters and evaluate the productivity of the different genotypes of quinoa for detecting genotypes amenable to selection. The experiment was conducted in crop years 2010/11 and 2011/12 in environment 1 and environment 2, respectively. In environment 1, the evaluation of 61 genotypes was performed, and in environment 2, 31 genotypes were evaluated. The experimental design was a randomized block with two replications; each plot measured 2.0 x 5.0 m (10 m²) and consisted of four rows spaced at 0.45 m. Data collected on the productivity, plant height at maturation and growth cycle were analyzed using an analysis of variance, average tests and estimates of the genetic parameters. The genotypes N24 and N08 were the only genotypes more productive than the other 46 genotypes, with values of productivity of 1,446.23 and 1,428.93 kg ha-1 and with a growth cycle of 117 and 111 days, respectively. The heritability values determined demonstrate the possibility of genetic gain using joint selection that involves two environments.