ABSTRACT. The continuous gains in cycles of recurrent selection have raised disagreement among researchers. Two hundred and forty-two full-sib families were obtained from CIMMYT and Piranão populations and evaluated in a simple lattice design in two environments to estimate the response to selection in the 11 th cycle of the UENF reciprocal recurrent selection program. No genotype x environment interaction was observed for most of the traits evaluated, indicating that a single recurrent selection program can be conducted for both sites. The population studied exhibited wide genotypic variability and heritability estimates ranged from 33 to 73%, indicating prospects of selection gain for the following cycles. The predicted genetic gain in yield was 12.90%. It is possible to conclude that the populations studied may be promising for the achievement of new selection cycles, which provides a continuous concentration of favorable alleles and the production of hybrids for the North and Northwest regions of the state of Rio de Janeiro.Keywords: genetic gains, selection index, interpopulation hybrids, longevity of recurrent selection.Resposta a seleção no 11º ciclo de seleção recorrente recíproca entre famílias de irmãos-completos de milho RESUMO. A contínua obtenção de ganhos em ciclos de seleção recorrente tem sido motivo de controvérsia entre pesquisadores. 242 famílias de irmãos-completos foram obtidas entre as populações CIMMYT e Piranão, e avaliadas em delineamento látice simples, em dois ambientes para investigar as estimativas da resposta à seleção no 11º ciclo do programa de seleção recorrente recíproca da UENF. Não houve interação genótipos por ambiente para a maioria das características avaliadas, indicando que um único programa de seleção recorrente pode ser conduzido para ambos os locais. A população avaliada revelou ampla variabilidade genotípica, com estimativas de herdabilidade variando de 33 a 73%, indicando perspectivas de ganho de seleção para os próximos ciclos. O ganho genético predito para produtividade foi de 12,90%. Conclui-se que as populações avaliadas são promissoras para a consecução de novos ciclos de seleção, proporcionando concentração contínua de alelos favoráveis e a produção de híbridos para as regiões Norte e Noroeste Fluminense.Palavras-chave: ganhos genéticos, índice de seleção, híbridos interpopulacionais, longevidade da seleção recorrente.

-The objectives of this study were to evaluate the relationships between morphological characteristics and fresh matter yield of cactus pear and identify their direct and indirect effects. Nineteen accessions were evaluated for the following traits: number (NCl), thickness (ThCl), length (LCl) and width (WCl) of cladodes, plant height (PH) and plant width (PW), and green matter yield (GMY), dry matter yield (DMY) and dry matter percentage (DM). The correlations were estimated, and path analysis was performed by the method proposed by Wright. GMY was strongly correlated with DMY, allowing indirect selection for this trait. NCl and ThCl had a direct effect on GMY and can be used for indirect selection or as secondary traits in the selection process. Given the lack of significant correlations between MS and DMY, it is possible to select a palm variety with high DMY and DM.

Genetic diversity among Capsicum accessions using RAPD markers ABSTRACT -The genus Capsicum has 27 species, being five domesticated and 22 semi-domesticated and wild ones. For an enhanced use of the germplasm in breeding programs it is necessary to know the accessions in the collections, to identify them and evaluate the genetic diversity. Objectives of this research were to quantify the genetic diversity among 70 Capsicum accessions, confirm their identification and verified possible duplicated accessions, using RAPD markers. Results showed that there is genetic diversity within and among species and were in agreement with botanical and morpho-agronomicclassifications. The identification of 53 accessions was confirmed (16 C. annuum, 7 C. frutescens, 14 C. baccatum and 16 C. chinense) and among botanically non-identified accessions results suggested that six belong to C. baccatum and five to C. chinense. The most distinct accession was UENF 1620, probably a wild species that is not represented in the collection yet.

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RESUMO O objetivo deste trabalho foi estudar o comportamento meiótico e a viabilidade polínica em quatro acessos das espécies