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RESUMO A qualidade fisiológica das sementes é um fator crucial no processo de produção, definindo o rendimento potencial dos cultivos. Tendo em vista a grande importância do feijão-caupi para a Região Nordeste do Brasil, bem como o fato das sementes crioulas serem mais comumente utilizadas pelos pequenos produtores, avaliou-se a viabilidade de sementes crioulas de cinco genótipos de feijão-caupi: Coruja; Rosinha; Sempre Verde; Cabeça de Gato; Paulistinha. As sementes foram adquiridas a partir de casas de sementes durante o ano de 2016 nas microrregiões da Chapada do Araripe, Barro, Cariri e Sertão de Senador Pompeu. As amostras foram submetidas aos testes de germinação, índice de velocidade de germinação e condutividade elétrica, além de determinações do percentual de umidade e peso de mil sementes. As análises mostraram diferenças de desempenho fisiológico entre os genótipos. Os acessos Rosinha e Cabeça de Gato tiveram desempenho superior no teste de germinação, sem diferença significativa entre os genótipos pelo teste de Scott-Knott (p < 0,01). O genótipo Rosinha ainda apresentou desempenho superior aos demais genótipos quanto a condutividade elétrica (68 μS cm-1 g-1) e a velocidade de germinação das sementes (17.25 in 24 hours). Neste contexto, a utilização de outros parâmetros é fundamental na diferenciação de genótipos que possuam o mesmo valor germinativo, mas que podem diferir em vigor.

The use of mixed models for evaluating diallel crosses is a highly timely option to the reliable prediction of progeny genetic values. In the sweet pepper crop, hybrids are commercially explored on a large scale, mainly because of their characteristics of economic importance. This study aimed to assess the potential of hybrids obtained from a partial diallel among five sweet pepper lines developed for the hydroponic cultivation system and two simple hybrids, by applying mixed models. It was performed crosses in the partial diallel scheme among the (L1B, L6, L7, L18, and L19) lines and the simple hybrids ‘Valdor’ and ‘Atlantis’. Plants were cultivated in hydroponic system with substrate and irrigated three times a day using nutrient solution. On the basis of mixed models, the following traits were assessed: mean fruit diameter (FD), mean fruit length (FL), mean fruit number per plant (FNP), mean fruit mass (FM), early yield (EYIELD), and mean fruit mass per plant (FMP). The L6 line was the one that showed the highest estimate of general combination capacity for FMP, FM, and EYIELD, proving to be promising for recommendation. The hybrid that provided the best specific combining ability for FD, FM, FMP, and EYIELD was L6 x ‘Valdor’. Triple hybrids were efficient to maximize yield for the traits of interest by the use of the mixed model.

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In the State of Espírito Santo (Brazil), family farmers have grown a number of maize varieties for decades, consisting of open-pollinated populations with valuable importance for the livelihood of smallholder farmers. The study aimed to analyze the cause and effect of associations between agro-morphological traits for increasing yields in maize populations cultivated. A total of 16 maize accessions of in vivo conservation works in eight different locations were evaluated, in a randomized complete block design with three replicates, totaling 48 experimental units. Genetic parameters, genotypic, phenotypic, and environmental correlation were estimated, and a path analysis was conducted. In general, accessions presented enough genetic variability, showing significant differences for all traits analyzed statistically (P≤0.05). The first cob insertion height with plant height and final plant stand variables presented heritability (h2) higher than 80%, suggesting that superior genotypes could be determined. Highest estimates of phenotypic correlations (rp) were found between the first cob insertion height with plant height and total number of cobs with number of cobs per plant (0.85). For estimates of genotypic correlations (rg), the highest were between (i) the first cob insertion height and plant height; (ii) number of grains per row and number of cobs per plant; (iii) total number of cobs and final plant stand. Maize final plant stand and one thousand seed weight were observed to be traits that could be determinant in grain yield increase.