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Three populations of popcorn from the Universidade Estadual do Norte Fluminense Darcy Ribeiro recurrent selection program (cycles C3, C4 and C5 from UNB2U), five simple hybrids provided by the Universidade Estadual de Maringá breeding program, five varieties (BRS Angela, UFVM-2 Barão de Viçosa, Viçosa, Beija-Flor and SAM) and three commercial hybrids (Zelia, Jade and IAC 112) were evaluated in five environments for their potential to be registered by the MAPA and recommended to producers in Northern and Northwestern Rio de Janeiro State. The experiment was arranged in a randomized block design, with three replications. The two main economic traits of the crops, grain yield (GY) and popping expansion (PE), were assessed. In the joint analysis of variance, significant differences were observed using the F test for the GY and PE traits. Regarding the genotype x environment interaction, only the GY was significant, thus revealing that the cultivar behavior varies according to the environment. The Pi statistics and the results for those traits showed that UNB2U-C5 and hybrid P1 x P7 have the potential to be recommended as new alternatives for producers in the region.

The aim of this work is to present the features of the popcorn cultivar UENF 14, developed from five cycles of recurrentselection of the population UNB-2U, to the scientific community. The cultivar produces yields of 3047.58 kg ha-1 and has poppingexpansion of 35.69 mL g-1.

The success of any recurrent selection program depends on the genetic variability of the evaluated population, which is used to refer to the diversity of existing alleles at many genetic loci. Thus, the goal of the present study was to investigate the impact of recurrent selection across nine cycles of a UENF-14 popcorn population through the analysis of genetic diversity and structure using microsatellite markers (EST-SSRs). Genomic DNA was extracted from young leaves of 25 individuals from each cycle (C0, C1 C2, C3, C4, C5, C6, C7, and C8), totaling 225 samples from the UENF-14 population. Fifty EST-SSR markers were used for the analysis of genetic diversity across the recurrent selection cycles, 16 of which were polymorphic. Thirty-four alleles were detected, with an average of 2.13 alleles per locus. Throughout all the recurrent selection cycles, there was a reduction in heterozygosity and an increase in inbreeding. The population structure showed a sharing of alleles, inferring that some may be directly related to the main selection characteristics.

O objetivo deste trabalho foi comparar quatro índices de seleção e o método REML/Blup na avaliação de ganhos genéticos preditos das características de interesse ao programa de melhoramento do milho-pipoca UENF 14. Foram avaliadas 200 progênies de irmãos-completos, em uma safra, em dois ambientes (regiões Norte e Noroeste do Estado do Rio de Janeiro), com duas repetições, o que totalizou 800 observações. Avaliaram-se as características altura média de plantas, altura média de inserção da primeira espiga, estande final, tombamento, diâmetro de colmo, prolificidade, rendimento e capacidade de expansão dos grãos. Entre os índices de seleção testados, o de Mulamba & Mock proporcionou os melhores resultados para a seleção das progênies de irmãos-completos. O método REML/Blup mostrou-se muito eficiente, tendo selecionado progênies com desempenhos relativos elevados e com ganhos genéticos preditos melhores que os dos índices de seleção testados. As progênies selecionadas com uso do método REML/Blup, para maior rendimento de grãos, não são as mesmas selecionadas para maior capacidade de expansão. O índice de Mulamba & Mock e o método REML/Blup proporcionam os melhores ganhos preditos para a população UENF 14.

O presente trabalho teve como objetivo fazer uma seleção prévia de pré-cultivares de milho-pipoca para o registro no MAPA, com base em diferentes caracteres, utilizando o índice de Garcia e o de soma de classificação, priorizando-se o rendimento de grãos e capacidade de expansão. Foram avaliados 16 genótipos de milho-pipoca, sendo oito variedades de polinização aberta (BRS Angela, UFVM2 - Barão de Viçosa, Viçosa, Beija-Flor, SAM, UNB2U-C3, UNB2U-C4 e UNB2U-C5) e oito híbridos (Zelia, Jade, IAC 112, P1 x P3, P1 x P7, P2 x P4, P2 x P9 e P3 x P7), em cinco ambientes. O delineamento experimental adotado foi blocos ao acaso, com três repetições, tendo sido avaliadas as características altura de planta, estande, tombamento, capacidade de expansão e rendimento de grãos. Os efeitos dos genótipos e ambientes foram significativos para todas as características, enquanto que suas interações o foram apenas para tombamento e rendimento de grãos. Os índices de Garcia e da soma de classificação foram positivamente correlacionados na classificação dos genótipos, ambos permitindo indicar as pré-cultivares UNB2U-C5 e P1 x P7 como as de melhor desempenho para regiões Norte e Noroeste do Estado do Rio de Janeiro.The present study aimed to select pre-cultivars of popcorn maize for registration in MAPA based on different characteristics, using the Garcia and total-classification indices, giving priority to grain yield and expansion capacity. Sixteen genotypes of popcorn maize: eight open-pollinated varieties (BRS Angela, UFVM2 - Barão de Viçosa, Viçosa, Beija-Flor, SAM, UNB2U-C3, UNB2U-C4 and UNB2U-C5) and eight hybrids (Zelia, Jade, IAC 112, P1 x P3, P1 x P7, P2 x P4, P2 x P9 and P3 x P7) were evaluated in five environments. The experimental design was of randomized blocks with three replications, where the characteristics of plant height, growth, droop, expansion capacity and grain yield were evaluated. The effects of genotype and environment were significant for all characteristics, while their interactions were only significant for droop and grain yield. The Garcia and the total-classification indices correlated positively in the classification of genotypes, both indicating the pre-cultivars UNB2U-C5 and P1 x P7 as having the best performance for regions in the north and northwest of the state of Rio de Janeiro.

In recent years, several new coffee cultivars recommended for different regions have been released. However, the performance of these varieties in many traditionally producing regions is unknown. Difference of climate and soil may jeopardize the productivity of the new cultivars and cause losses to farmers. The objective of this study is to evaluate the vegetative growth and productive genotypes of C. arabica in the conditions of the Northwestern Rio de Janeiro State, Brazil. The experiment was settled in 2007, in Panorama 1 Farm, located in the municipality of Varre Sai, RJ. Twenty-five genotypes of C. arabica were planted in a spacing of 2.5 × 0.8 m, using a completely randomized design with five replications and eight plants per plot. There were eight measurements of vegetative growth represented by plant height, stem diameter and number of plagiotropic branches. Assessments of productivity were also performed in years 2009 and 2010. There was a positive phenotypic correlation among vegetative characteristics and between vegetative characteristics and yield in the first harvest, while in the second harvest only the number of plagiotropic branches was positively correlated with yield. Up to date, the genotypes Catucaí amarelo 2 SL, Catiguá MG 02, Acauã, Palma II, Sabiá 398, IPR 103/ Iapar, IPR 100/Iapar, H 419-10-6-2-12-1, Catucaí amarelo 24 / 137, Iapar 59, Catucaí amarelo 20/15, H 419-10-6-2-5-10-1 and H 419-10-6-2-5-1 had the highest average yield after two harvests.