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This study aimed to estimate and compare parameters of adaptability and stability for maize grain yield in a variety of environments by different projection methods. Data from experiments on 36 maize genotypes, in simple lattice 6x6, in 2012/13 season performed at nine growing locations in central Brazil were used. Adaptability and stability analyses were performed using the methods of Lin & Binns (1988) with decomposition, MHPRVG through REML/BLUP, AMMI-Biplot, and GGE-Biplot analysis. These methods have similarities in terms of genotype ordering but differ in precision and amount of information provided on genotype-environment (GxE) interactions. When compared to GGE-Biplot, AMMI method retained a good percentage of the total square sum, based on pattern of GxE interaction. The method of Lin & Binns with decomposition is similar to MHPRVG, but these one is more accurate, practice and informative. MHPRVG and GGE-Biplot methods should be used together to select the most promising genotypes. The genotypes G5 and G8 can be recommended for cultivation in central Brazil due to their adaptability, stability, and yield.

As part of the Universidade Estadual do Norte Fluminense recurrent selection program of popcorn, we evaluated full-sib families of the sixth cycle of recurrent selection and estimated genetic progress for grain yield and expansion capacity. We assessed 200 full-sib families for 10 agronomic traits, in a randomized block design, with two replications within sets in two environments: Campos dos Goytacazes and Itaocara, in the State of Rio de Janeiro, Brazil. There were significant differences for families/"sets" for all traits, indicating genetic variability that could be exploited in future cycles. In the selection of superior progenies, the Mulamba and Mock index gave the best gains for popping expansion (PE) and grain yield (GY), with values of 10.97 and 15.30%, respectively, using random economic weights. By comparing the evolution of the means obtained for PE and GY in the cycles C(0), C(1), C(2), C(3), C(4), C(5), and predicted for C(6), a steady increase was observed for both PE and GY, with the addition of 1.71 mL/g (R(2) = 0.93) and 192.87 kg/ha (R(2) = 0.88), respectively, in each cycle. Given the good performance of this popcorn population in successive cycles of intrapopulation recurrent selection, we expect that a productive variety with high expansion capacity will soon be available for producers in the north and northwest regions of Rio de Janeiro State, Brazil.

This study aimed to obtain estimates of stability and adaptability of phase launched materials and materials recommended in the country, for the northern and northwestern regions of Rio de Janeiro State, Brazil, and made a comparative analysis of different methods to evaluate stability and adaptability of grain yield and popping expansion. To this end, 10 genotypes were evaluated (UNB2U-C3, UNB2U-C4, BRS Angela, ViA§osa, Beija-Flor, IAC 112, IAC 125, ZA©lia, Jade, and UFVM2 BarA£o de ViA§osa) in five environments. The Yates and Cochran method revealed that genotypes UFV2M BarA£o de ViA§osa, BRS Angela and UNB2U-C3 were the most stable for grain yield. This method also indicated superiority of genotypes UNB2U-C3, UNB2U-C4, BRS Angela, ViA§osa, IAC 125, and ZA©lia for popping expansion. The Plaisted and Peterson and Wricke methods demonstrated that genotypes ZA©lia and UNB2U-C4 were the most productive and stable. These methods indicated genotypes UNB2U-C3 and BRS Angela as the most stable for popping expansion. The Kang and Phan ranking system uses methods based on analysis of variance and classified population UNB2U-C4 as the genotype with the highest stability of grain production and confirmed cultivar BRS Angela as the most stable for popping expansion. Genotypes IAC 112 and UNB2U-C4 were the most stable and adapted for grain yield, according to the Lin and Binns method. The Pi statistics also ranked UNB2U-C3 and UNB2U-C4 as the genotypes with the best predictability and capacity for popping expansion. This study aimed to obtain estimates of stability and adaptability of phase launched materials and materials recommended in the country, for the northern and northwestern regions of Rio de Janeiro State, Brazil, and made a comparative analysis of different methods to evaluate stability and adaptability of grain yield and popping expansion. To this end, 10 genotypes were evaluated (UNB2U-C3, UNB2U-C4, BRS Angela, ViA§osa, Beija-Flor, IAC 112, IAC 125, ZA©lia, Jade, and UFVM2 BarA£o de ViA§osa) in five environments. The Yates and Cochran method revealed that genotypes UFV2M BarA£o de ViA§osa, BRS Angela and UNB2U-C3 were the most stable for grain yield. This method also indicated superiority of genotypes UNB2U-C3, UNB2U-C4, BRS Angela, ViA§osa, IAC 125, and ZA©lia for popping expansion. The Plaisted and Peterson and Wricke methods demonstrated that genotypes ZA©lia and UNB2U-C4 were the most productive and stable. These methods indicated genotypes UNB2U-C3 and BRS Angela as the most stable for popping expansion. The Kang and Phan ranking system uses methods based on analysis of variance and classified population UNB2U-C4 as the genotype with the highest stability of grain production and confirmed cultivar BRS Angela as the most stable for popping expansion. Genotypes IAC 112 and UNB2U-C4 were the most stable and adapted for grain yield, according to the Lin and Binns method. The Pi statistics also ranked UNB2U-C3 and UNB2U-C4 as the genotypes with the best predictability and capacity for popping expansion.

In Brazil, using combining ability of popcorn genotypes to achieve superior hybrids has been unsuccessful because the local genotypes are all members of the same heterotic group. To overcome this constraint, 10 lines (P(1) to P(10)) with different adaptations to tropical or temperate edaphoclimatic environments were used to obtain 45 F(1) hybrids in a complete diallel. These hybrids and three controls were evaluated in two environments in Rio de Janeiro State. Grain yield (GY), popping expansion (PE), plant height (PH), ear height (EH), and days to silking (FL) were evaluated in randomized complete blocks with three replications. Significant differences between genotypes (Por= 0.05) were detected for GY, PE and EH. General combining ability was significant for EH, PH, PE, and GY, and specific combining ability was significant only for PE and GY. The most promising inbred lines that improved GY were P(3) and P(4), unlike P(8), P(9) and P(10), which improved PE, and P(2), which improved both PE and GY. The additive effects were much more important for PE than for GY. The hybrid combinations gave positive estimates of heterosis for GY but not for PE.

RESUMO - A adequacao do arranjo populacional esta entre as tecnicas que podem maximizar a produtividade da cultura do milho. Dai a importância das pesquisas que buscam estudar o desempenho de cultivares de milho e milhos especiais, a fim de determinar o arranjo de plantas ideal. O objetivo deste trabalho foi avaliar o desempenho da variedade UENF-14, de milho pipoca, cultivada em diferentes arranjos populacionais, na safra e safrinha, para otimizar a recomendacao fitotecnica para os produtores rurais do Norte Fluminense. Foram instalados dois experimentos em Campos dos Goytacazes-RJ. Um na safrinha 2011 utilizando a variedade UENF-14 e o hibrido experimental P2 x P9, e o outro na safra 2011-2012, com a variedade UENF-14 e o hibrido comercial IAC-112. O delineamento experimental, nos dois experimentos, foi o de blocos casualizados arranjados em parcelas subsubdivididas, em que as parcelas foram compostas pelos genotipos, as subparcelas constituidas pelos espacamentos entre linhas de semeadura (0,45, 0,60 e 0,90 m) e as subsubparcelas compostas pelas densidades de plantas (60.000, 75.000 e 90.000 plantas ha-1). A UENF-14 apresentou desempenho superior aos hibridos, demonstrando seu potencial para cultivo na regiao Norte Fluminense. Houve aumento do rendimento de graos com a diminuicao do espacamento entre linhas de plantio. Para a variedade UENF-14, a reducao do espacamento entre linhas de plantio foi vantajosa para a producao de graos, independentemente da epoca de semeadura. Palavras-chave: Zea mays L., densidade de semeadura, espacamento entre linhas, epocas de semeadura. POPULATION ARRANGEMENT FOR THE VARIETY OF POPCORN UENF-14 ABSTRACT - The adequacy of the maize population arrangement is among the most important techniques for obtaining higher yields. Therefore, many researchers have been conducting an attempt to study the performance of corn and specialty corn. The objective was to evaluate the performance of the popcorn variety UENF-14 in different population arrangements, in the harvest season and off-season. Two experiments were carried out in Campos dos Goytacazes, North of Rio de Janeiro State, Brazil, in the off-season 2011, using the UENF-14 variety and the experimental hybrid P2 x P9, and in the season 2011-2012 using UENF-14 and the commercial hybrid IAC-112. The treatments were arranged in randomized complete block design with split plots, in which plots were composed by popcorn genotypes, the subplots consisting of three spacings between sowing lines (0.45, 0.60 and 0.90 m) and the subsubplots composed of three plants per hectare densities (60,000, 75,000 and 90,000 plants.ha-1). The variety UENF-14 presented higher performance than the hybrids, demonstrating its potential for recommendation to the North of Rio de Janeiro State. There was an increase of grain yield by reducing the spacing between the plants rows. The cultivation of the variety UENF-14 reducing the spacing between rows was advantageous for grain production, regardless of planting date. Keywords: Zea mays L., densities of plants, spacing between rows, sowing times.

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. Com o objetivo de investigar a potencialidade de registro no MAPA para indicação aos produtores do Norte e Noroeste Fluminense, três populações de milho pipoca oriundas do programa de seleção recorrente da Universidade Estadual do Norte Fluminense Darcy Ribeiro (ciclos C3, C4 e C5 de UNB2U), cinco híbridos simples cedidos pelo programa de melhoramento da Universidade Estadual de Maringá, bem como cinco variedades (BRS Angela, UFVM-2 Barão de Viçosa, Viçosa, Beija-Flor e SAM) e três híbridos comerciais (Zelia, Jade e IAC 112) foram avaliados em cinco ambientes. O delineamento experimental adotado foi blocos ao acaso, com três repetições, tendo sido avaliadas as duas principais características da cultura de importância econômica: produtividade de grãos (GY) e capacidade de expansão (PE). Na análise de variância conjunta, observaram-se diferenças significativas pelo teste F para as características GY e PE. Em relação à interação genótipos x ambientes, apenas GY foi significativa, evidenciando comportamento diferenciado das cultivares nos ambientes. Pela estatística Pi e os resultados para estas características demonstram que a população UNB2U-C5 e o híbrido P1 x P7 têm potencial para recomendação como nova opção de cultivo para os produtores da região.

Com o intento de selecionar progênies superiores para a efetiva concentração de alelos favoráveis em uma população de quinto ciclo de seleção recorrente intrapopulacional em famílias de irmãos-completos de milho pipoca, avaliaram-se 200 famílias quanto a seis características agronômicas, incluindo rendimento de grãos e capacidade de expansão, em delineamento aleatorizado em blocos com duas repetições dentro de 'sets' em dois ambientes distintos: Colégio Estadual Agrícola Antônio Sarlo, em Campos dos Goytacazes, e Estação Experimental da PESAGRO-RIO, em Itaocara, Rio de Janeiro, em 2007/2008. Houve diferenças significativas para famílias/"sets" para todas as características, indicando a presença de variabilidade genética a ser explorada nos futuros ciclos. Na seleção das progênies superiores o índice de Mulamba e Mock resultou em ganhos proporcionais mais adequados para capacidade de expansão e rendimento de grãos, com valores respectivos de 6,01 e 8,53%, na utilização de pesos econômicos arbitrários. Aiming to select superior progenies for concentration of favorable alleles in a popcorn population on the fifth cycle of intrapopulation full-sib recurrent selection, two hundred progenies were evaluated for six agronomic traits, including grain yield and popping expansion, in randomized complete block design with two replications within sets, in two distinct environments: Colégio Estadual Agrícola Antônio Sarlo, in Campos dos Goytacazes, and Experimental Station of PESAGRO-RIO, located in Itaocara, Rio de Janeiro State, in 2007/2008. There were significant differences among families within sets in all traits, indicating the presence of genetic variability to be exploited in the future cycles. The utilized selection indexes were the Mulamba and Mock; and Smith and Hazel. The Mulamba and Mock index propitiated more elevated magnitudes of the predicted gains for most of the traits, including popping expansion and grain yield, with values of 6.01 and 8.53%, respectively, utilizing arbitrary weight attributed by tentative.