Abstract The objective of this work was to select superior cowpea lines derived from local cultivars for the semiarid region of southeastern Piauí, Brazil. A total of 38 genotypes (36 lines and two ...commercial cultivars) were evaluated in a randomized complete block design, with two replicates, in the municipality of Ipiranga do Piauí, in the state of Piauí. The following traits were evaluated: number of days to the onset of flowering, pod length, number of grains per pod, weight of 100 grains, commercial grain quality, and grain yield. Deviance analyzes were performed using the restricted maximum likelihood and best unbiased predictor approach, the parameters and genetic values were estimated, and simultaneous selection was carried out via the sum of ranks index. The likelihood ratio test showed a significant difference between the evaluated genotypes. Lines 36, 5, 24, 8, 2, 23, 29, 28, 34, 6, 19, 11, 7, and 20 are superior for the set of evaluated traits and, therefore, are the most promising to compose the advanced trial of the cowpea breeding program and to generate cultivars for family farmers in the semiarid region of southeastern Piauí.
Resumo O objetivo deste trabalho foi selecionar linhagens superiores de feijão-caupi derivadas de cultivares locais para a região semiárida do sudeste do Piauí, Brasil. Foram avaliados 38 genótipos (36 linhagens e duas cultivares comercias) em um ensaio conduzido em delineamento de blocos ao acaso, com duas repetições, no município de Ipiranga do Piauí, no estado do Piauí. Foram avaliados os seguintes caracteres: número de dias para o início do florescimento, comprimento de vagem, número de grãos por vagem, peso de 100 grãos, qualidade comercial do grão e produtividade de grãos. Análises de deviance foram realizadas pela abordagem da máxima verossimilhança restrita e do melhor preditor não viesado, os parâmetros e os valores genéticos foram estimados, e a seleção simultânea foi realizada via índice de soma de postos. O teste da razão de verossimilhança mostrou diferença significativa entre os genótipos avaliados. As linhagens 36, 5, 24, 8, 2, 23, 29, 28, 34, 6, 19, 11, 7 e 20 são superiores para o conjunto de caracteres avaliados e, portanto, são as mais promissoras para compor o ensaio avançado do programa de melhoramento genético de feijão-caupi e gerar cultivares para os agricultores familiares da região semiárida do sudeste piauiense.
Abstract
Water deficits have been considered the most restrictive environmental constraint on agricultural production worldwide. The current study aimed to investigate the role of silicon nutrition ...(Si) in activating defence mechanisms against drought damage in cowpea cultivars. The experiments were carried out in a randomized block design in a 2 × 2 × 4 factorial scheme, corresponding to two cowpea cultivars (BRS Novaera and BRS Tumucumaque), two water regimes (control well‐irrigated and water deficit) and four Si levels (0, 1.0, 2.0 and 4.0 mM). Plant growth and physiological and biochemical indicators were evaluated 28 days after drought imposition. Drought significantly reduced the photosynthetic pigments (Chl
b
and Chl
total
), gas exchanges (net photosynthesis, transpiration and stomatal conductance) and, consequently, all growth parameters of cowpea plants compared with well‐irrigated plants. However, Si at 2.0 mM activated critical responses in the BRS Novaera cultivar under drought, almost recovering plant performance and increasing drought tolerance. The beneficial Si‐induced effects were closely related to increased accumulation of Si, carbohydrates and free amino acids that likely promoted osmoregulation and were associated with an improved antioxidant system composed of proline and the activity of SOD, CAT and APX. These metabolic alterations were sufficient to enable enhanced net photosynthesis and plant growth. In conclusion, Si counteracts the deleterious effects of water deficit by efficiently inducing antioxidant defence and photosynthetic performance in Novaera plants. Si nutrition may constitute a potential strategy to cultivate cowpea plants in water‐scarce areas from arid and semiarid regions.
Introduction Salicylic acid has shown promise in alleviating water stress in cultivated plants. However, there is a lack of studies confirming its effectiveness in cowpea plants grown in field ...conditions. Therefore, this research aimed to evaluate the use of salicylic acid as a water stress mitigator in cowpea cultivars under different irrigation depths in field conditions. Methods Four cowpea cultivars (BRS Novaera, BRS Tapaihum, BRS Pujante, and BRS Pajeú) were subjected to different treatments: control (W100: 100% replacement of crop evapotranspiration – ETc), W50 (50% of ETc), W50+SA2 (50% of ETc + 276 mg L -1 of SA), and W50+SA4 (50% of ETc + 552 mg L -1 of SA). The treatments were combined in a 4×4 factorial scheme with three replications, arranged in a randomized block design. Results Water restriction had a negative impact on the water status, growth, gas exchange, and production of the cultivars while also leading to changes in the antioxidant metabolism and osmolyte concentration. The application of SA enhanced antioxidant activity and the synthesis of osmotic adjusters under stress conditions. The most effective concentration was 276 mg L -1 in stage R2 and 552 mg L -1 in stage V7, respectively. The BRS Pujante cultivar showed increased productivity under water restriction with SA application, while the BRS Tapaihum was the most tolerant among the cultivars studied. Discussion In summary, our findings underscore the importance of using SA to mitigate the effects of water restriction on cowpea cultivation. These discoveries are crucial for the sustainability of cowpea production in regions susceptible to drought, which can contribute to food security. We further add that the adoption of new agricultural practices can enhance the resilience and productivity of cowpea as an essential and sustainable food source for vulnerable populations in various parts of the world.
Abstract
This study aims to compare the grain protein profile of four Brazilian cowpea cultivars (
BRS Aracê, BRS Itaim, BRS Pajeú, and BRS Xiquexique)
by two-dimensional electrophoresis (2-DE) and ...principal component analysis (PCA). 2-DE efficiently separate cowpea protein profiles, showing high homogeneity among the four cultivars. In addition, the principal component analysis indicated that there is a difference in abundance of proteins among the cultivars. The cultivars BRS Aracê and BRS Xiquexique, both biofortified in iron and zinc, were separated from the cultivars BRS Itaim and BRS Pajeú. These results demonstrate that protein profiles can be used to discriminate cowpea varieties.
Graphical Abstract
The objective of this work was to select cowpea genotypes simultaneously for high yield of immature grains, adaptability, and genotypic stability, taking into account genotype x environment ...interactions. The mixed models restricted maximum likelihood (REML)/best linear unbiased prediction (BLUP) were used. Sixteen cowpea genotypes were evaluated in nine environments, consisting of a combination of location (Pentecoste in the state of Ceará, Acaraú in Ceará, Teresina in Piauí, and Mossoró in Rio Grande do Norte, Brazil) and year (2012, 2013, 2014, 2015, and 2017). In all trials, a randomized complete block design with four replicates was used. Significant differences were observed for effects of genotypes and the genotype x environment interaction. Environmental variance was the largest component of phenotypic variance, followed by the genotype x environment interaction and genotypic variances. The immature grain yield of the evaluated cowpea genotypes interacts strongly with the studied environments, resulting in a low genotypic correlation between environments. The MNC00-595F-27, MNC05-847B-123, and BRS Tumucumaque cowpea genotypes present high yield of immature grains, adaptability, and genotypic stability, being the most suitable for cultivation in the states of Ceará, Piauí, and Rio Grande do Norte or in other environments with similar soil and climatic conditions.
Resumo: O objetivo deste trabalho foi selecionar genótipos de feijão-caupi simultaneamente para alta produção de grãos imaturos, adaptabilidade e estabilidade genotípica, ao se considerar interações genótipos x ambientes. Foram utilizados os modelos mistos máxima verossimilhança restrita (REML)/melhor predição linear não viciada (BLUP). Avaliaram-se 16 genótipos de feijão-caupi em nove ambientes, que consistiram de combinação de local (Pentecoste no Ceará, Acaraú no Ceará, Teresina no Piauí e Mossoró no Rio Grande do Norte) e ano (2012, 2013, 2014, 2015 e 2017). Em todos os ensaios, utilizou-se o delineamento de blocos ao acaso com quatro repetições. Foram observadas diferenças significativas para os efeitos de genótipos e interação genótipo x ambiente. A variância ambiental foi o maior componente da variância fenotípica, seguido das variâncias da interação genótipo x ambiente e genotípica. A produtividade de grãos imaturos dos genótipos de feijão-caupi avaliados interage fortemente com os ambientes estudados, o que resulta em baixa correlação genotípica entre os ambientes. Os genótipos de feijão-caupi MNC00-595F-27, MNC05-847B-123 e BRS Tumucumaque apresentam alta produtividade de grãos imaturos, adaptabilidade e estabilidade genotípica, sendo os mais recomendáveis para cultivo nos estados do Ceará, Piauí e Rio Grande do Norte ou em outros ambientes com condições climáticas e de solo similares.
Cowpea bean is a common crop quite appreciated in Brazil. However, it is known that its low yield depending on soil and climatic conditions. The aim of this research is the selection of ...high-performance black-eyed cowpea through GYT biplot analysis. Twelve (12) cowpea bean strains were assessed between 2016 and. The study followed a randomized complete block design, with four repetitions; two commercial cultivars were used ascheck. The following variables were assessed: number of days required for flowering, final stand, value for cultivation, pod yield, pod length, mean number of grains per pod and grain weight. The analysis of variance showed genetic variability between strains, differences between the assessed years and different strain-performance in each growing year. Based on the GYT biplot graph, cultivar BRS Itaim, and strains L9 and L7 recorded the best performance for the set of yield characteristics. Variable 'pod length' had positive correlation to bedding, number of days required for flowering and number of grains per pod. Variable '100-grain weight' had positive correlation to final stand, pod yield and mean grain weight per pod. Strains L9, L7 and cultivar BRS Itaim recorded the best yield regarding the assessed variables.
O objetivo deste trabalho foi avaliar a variabilidade de genótipos de feijão-caupi e selecionar aqueles com potencial para o mercado de vagens e grãos verdes. Em 2012, foram avaliados 16 genótipos em ...dois experimentos (sequeiro e irrigado), em delineamento de blocos ao acaso, com quatro repetições. Foram avaliados os caracteres: número de dias para o início da floração, comprimento de vagem verde, número de grãos por vagem verde, massa de cem grãos verdes, produtividade de vagens verdes, produtividade de grãos verdes e índice de grãos verdes. A maioria dos caracteres apresentou diferenças quanto ao ambiente de cultivo, mas a resposta dos genótipos às variações ambientais foi similar. Os genótipos, sob irrigação, apresentaram produtividade de vagens e grãos verdes similar à das testemunhas. A cultivar Azulão-MS, em sequeiro, apresentou alto potencial para a produção de vagens verdes, no entanto, com baixa relação grão verde/vagem verde. A cultivar BRS Tumucumaque apresenta potencial para a produtividade de grãos verdes em sequeiro, enquanto a linhagem MNC00-595F-27 produz mais em condições de irrigação.
ABSTRACT Flour production through milling is an alternative for the cowpea processing, when the aim is to obtain a product with higher added value. The objective of this work was to determine the ...chemical composition, the granulometry, and evaluate the microbiological characteristics of whole-bean flours from five cowpea cultivars (BRS Cauamé, BRS Guariba, BRS Xiquexique, BRS Novaera and BRS Itaim). Cowpea beans were dried in a oven (Fanem, 320-SE) at 50 °C for 6 hours, milled in a cyclone-type rotor mill (Tecnal, TE-651/2) and, subsequently, in a pulverizer-type semi-industrial mill (Fritsch, Pulverisette 14) to obtain the flour. The flour centesimal composition, total energetic value, mineral content, granulometry, microbiological characteristics, and technological properties-flour water absorption and solubility in water-were analyzed. All analyzes were performed in triplicate and the results expressed in mean ± standard deviation. The means were compared by the Scott-Knott test (p ≤ 0.05). The flour centesimal composition presented (g per 100 g of flour): 7.13 to 10.33 of moisture, 2.06 to 3.65 of ashes, 1.53 g to 2.90 of lipids, 21.73 to 25.77 of proteins, and 58.08 to 64.02 of carbohydrate. The flours had on average 359.04 Kcal (100 g) and presented high iron, zinc, copper, manganese, phosphorus and magnesium contents. The whole-bean flours from the cultivars BRS Cauamé and BRS Xiquexique are sources of calcium. Regarding the microbiological characteristics, all flours are innocuous. The water absorption index were within 1.77 and 2.20 g g-1 and the water solubility index within 17 and 23%. All whole-bean flours had good nutritional, technological and microbiological characteristics, and thus potential for use in bakery products.
RESUMO A produção de farinha por meio da moagem é uma alternativa para o processamento do feijão-caupi, na busca de um produto com maior valor agregado. Objetivou-se determinar a composição química, a granulometria e avaliar microbiologicamente farinhas integrais de cinco cultivares (BRS Cauamé, BRS Guariba, BRS Xiquexique, BRS Novaera e BRS Itaim) comerciais de feijão-caupi. Para a obtenção das farinhas procedeu-se a secagem dos grãos em estufa (marca Fanem, modelo 320-SE) a 50 °C, por 6 horas; com posterior moagem, primeiramente em moinho de facas tipo ciclone (marca Tecnal, modelo TE-651/2) e posteriormente, em moinho semi-industrial tipo pulverizador (marca Fritsch, modelo Pulverisette 14). Analisaram-se a composição centesimal, o valor energético total, o conteúdo mineral, a granulometria, as características microbiológicas, e as tecnológicas quanto a absorção e solubilidade em água das farinhas. As análises foram realizadas em triplicata e os resultados expressos em média ± desvio padrão. As médias foram comparadas pelo teste de Scott-Knott (p≤0,05). Os valores encontrados para composição centesimal foram: umidade entre 7,13 a 10,33 g/100g; cinzas de 2,06 a 3,65 g/100g; lipídios variaram de 1,53 g a 2,90 g/100g; proteínas entre 21,73 a 25,77 g/100g e o conteúdo de carboidratos variou de 58,08 a 64,02 g/100g. As farinhas ofertaram em média 359,04 Kcal/100g e apresentaram elevado teor de ferro, zinco, cobre, manganês, fósforo e magnésio, sendo as das cultivares BRS Cauamé e BRS Xiquexique fontes de cálcio. Sob o aspecto microbiológico as farinhas apresentaram-se inócuas. Os valores de IAA variaram de 1,77 a 2,20 g/g e ISA de 17 a 23%. Concluiu-se que todas as farinhas apresentaram bom perfil nutritivo, tecnológico e microbiológico, apresentando, portanto potencial para utilização no desenvolvimento de produtos de panificação.
In cowpea breeding, multi‐environment trials are conducted to select lines with high yield. The occurrence of genetic and/or statistical imbalance is common in these experiments, in addition to the ...possibility of (co)variance between genetic and non‐genetic effects. We explore the restricted maximum likelihood/best linear unbiased prediction features to select the model with the most appropriated covariance structure and compare the results with the traditional model (homogenous variances and no covariances). Then, 17 inbred lines and three cultivars were evaluated in six experiments during two crop years in the semiarid zone of Northeast Brazil. The trait evaluated was the 100‐grain weight. We selected the best model considering the Akaike Information Criterion. The model with diagonal structure for the residual effects and heterogeneous compound symmetry for the genetic effects had the best fit. The predicted genetic gain of lines selected in this model was 1.18% higher compared to the traditional model. Modeling different (co)variance structures for genetic and non‐genetic effects is an efficient approach in selecting superior genotypes in multi‐environment trials in cowpea breeding.
Core Ideas
Multi‐environment trials have peculiarities that must be accounted for in the statistical modeling.
The genetic and residual homoscedasticity assumption is unlikely to be true.
By modeling the covariance structures of a mixed model random effects, there are higher accuracy and gains.
The cowpea breeder must not ignore this step in the breeding process.
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