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1.
Ciênc. rural (Online) ; 49(3): e20180045, 2019. tab, graf
Article in English | LILACS | ID: biblio-1045320

ABSTRACT

ABSTRACT: The aim of this study was to use quantile regression (QR) to characterize the effect of the adaptability parameter throughout the distribution of the productivity variable on black bean cultivars launched by different national research institutes (research centers) over the last 50 years. For this purpose, 40 cultivars developed by Brazilian genetic improvement programs between 1959 and 2013 were used. Initially, QR models were adjusted considering three quantiles (τ = 0.2, 0.5 and 0.8). Subsequently, with the confidence intervals, quantile models τ = 0.2 and 0.8 (QR0.2 and QR0.8) showed differences regarding the parameter of adaptability and average productivity. Finally, by grouping the cultivars into one of the two groups defined from QR0.2 and QR0.8, it was reported that the younger cultivars were associated to the quantile τ = 0.8, i.e., those with higher yields and more responsive conditions indicating that genetic improvement over the last 50 years resulted in an increase in both the productivity and the adaptability of cultivars.


RESUMO: Neste estudo objetivou-se utilizar a regressão quantílica (RQ) para caracterizar o efeito do parâmetro de adaptabilidade ao longo de toda a distribuição da variável produtividade em cultivares de feijão preto lançadas por diferentes instituições nacionais de pesquisa nos últimos 50 anos. Para tanto utilizou-se 40 cultivares desenvolvidas pelos programas brasileiros de melhoramento genético entre os anos de 1959 a 2013. Inicialmente foram ajustados modelos de RQ considerando três quantis (τ=0,2, 0,5, 0,8). Posteriormente, com os intervalos de confiança verificou-se que os modelos quantílicos τ=0,2 e 0,8 (RQ0,2 e RQ0,8) apresentaram diferenças quanto ao parâmetro de adaptabilidade e produtividade média. Finalmente, por meio do agrupamento das cultivares em um dos dois grupos definidos a partir de RQ0,2 e RQ0,8, constatou-se que as cultivares mais novas foram associadas ao quantil τ = 0,8, ou seja, aquelas com maiores produtividades e mais responsivas as condições ambientais indicando que o melhoramento ao longo dos últimos 50 anos possibilitou o incremento tanto na produtividade quanto na adaptabilidade das cultivares.

2.
Arch. latinoam. nutr ; 66(1): 17-25, mar. 2016. tab, ilus
Article in Spanish | LIVECS, LILACS | ID: biblio-1023154

ABSTRACT

Actualmente los fitoesteroles son adicionados a los alimentos industrializados, lo que aumenta su costo y por lo tanto limita su consumo. Este manuscrito tiene como objetivo identificar alimentos que son una fuente natural de fitoesteroles, así como también analizar cómo el ambiente y el manejo productivo modifican su contenido, relacionando estos aspectos con la salud. Los fitoesteroles son compuestos presentes en las plantas con propiedades hipocolesterolémicas, que pueden contribuir a prevenir las enfermedades cardiovasculares. La ingesta diaria estimada de fitoesteroles varía entre 160 y 500 mg/día, sin embargo su acción beneficiosa se logra con consumos de 1500 mg a 2400 mg diarios. Las semillas de oleaginosas y de cereales son las mayores fuentes naturales de fitoesteroles. El amaranto es considerado un pseudocereal y entre los cereales tiene la mayor concentración de fitoesteroles con 178 mg/100 g, valor 5 veces superior al de la harina de trigo. El ambiente modifica el contenido de fitoesteroles de los alimentos, la sequía y temperaturas altas duplican su contenido en las semillas; la fertilización nitrogenada y la fecha de siembra pueden provocar cambios, pero se requieren más estudios al respecto. La selección de genotipos con mayor contenido de fitoesteroles y el estudio de la interacción genotipo ambiente, permitirá la identificación de aquellos genotipos con adaptación local para este carácter. El manejo productivo podrá aumentar la oferta de alimentos naturales ricos en fitoesteroles, contribuyendo a una mayor oferta de alimentos protectores de la salud(AU)


Currently phytosterols are added to processed foods, which increase their cost and therefore limits its use. This manuscript aims to identify foods that are a natural source of phytosterols, as well as analyze how the environment and production management modify its content, linking these aspects with health. Phytosterols are compounds found in plants with hypocholesterolemic properties, which may help prevent cardiovascular diseases. The estimated daily intake of phytosterols varies between 160 and 500 mg/day, but its beneficial effect is achieved with 1,500 to 2,400 mg daily consumption. Oil and cereal seeds are the largest natural sources of phytosterols. Amaranth is considered a pseudocereal and among the cereals has the highest concentration of phytosterols with 178 mg/100 g, value 5 times higher than wheat flour. Environment modifies phytosterol content in food, drought and high temperatures can double their content in seeds; nitrogen fertilization and planting date can cause changes, but more studies are needed. The selection of genotypes with higher phytosterol content and studying the genotype x environment interaction, allow the identification of those genotypes with local adaptation for this character. The production management will increase the supply of natural foods rich in phytosterols, contributing to a greater supply of health protective foods(AU)


Subject(s)
Humans , Male , Female , Phytosterols/administration & dosage , Amaranthus , Food, Genetically Modified , Dyslipidemias/etiology , Industrialized Foods , Cardiovascular Diseases , Chronic Disease
3.
Ciênc. rural ; 45(11): 1980-1986, Nov. 2015. tab
Article in Portuguese | LILACS | ID: lil-762926

ABSTRACT

RESUMO:O objetivo deste trabalho foi estudar os parâmetros de adaptabilidade e estabilidade fenotípica e avaliar o incremento na produtividade de grãos em genótipos de feijão preto, desenvolvidos pelos programas brasileiros de melhoramento genético entre os anos de 1960 a 2013. Os experimentos foram realizados considerando 38 cultivares e duas linhagens em quatro ambientes (Coimbra e Viçosa nas safras da seca e de inverno de 2013), usando um delineamento em blocos casualizados com três repetições. Os resultados evidenciaram incremento efetivo na produtividade de grãos, proporcionado pela recomendação de novas cultivares pelos programas de melhoramento de feijão do Brasil nas últimas cinco décadas. Além disso, a análise da interação GxA indicou que as cultivares recomendadas após o ano de 2005 foram as que apresentaram conjuntamente altas produtividades de grãos, ampla adaptabilidade e alta previsibilidade de comportamento.


ABSTRACT:The objective of this research was to study the parameters of adaptability and phenotypic stability and estimate the increase in grain yield in black common bean genotypes developed by brazilian breeding programs between the years 1960-2013. The experiments were carried out considering 38 cultivars and two lines in four different environments (Coimbra and Viçosa cities, and dry and winter seasons of 2013 year) by using a randomized block design with three replications. Results showed an effective increasing of the grain yield provided by the recommendation of new cultivars from different Brazilian breeding programs in the past five decades. In addition, the GxE analysis interaction indicated that cultivars recommended after the year 2005 were those with high average grain yield, wide adaptability and high predictability.

4.
Br Biotechnol J ; 2014 Apr; 4(4): 339-349
Article in English | IMSEAR | ID: sea-162441

ABSTRACT

This study was carried out to identify the yield stability and adaptability of the grain maize genotypes (parental inbred lines, F1-hybrids and check varieties), using Additive Main Effects and Multiplicative Interaction (AMMI). A field experiment was executed during the winter and summer seasons of 2009 and 2010 at two locations, Shambat and Elrawakeeb, Sudan. A split-plot design with three replications was used to layout the experiment. The inbred lines and their F1-hybrids were evaluated in the field under normal irrigation and water-stress conditions. The results showed that, highly significant differences were detected among genotypes, environments and for G×E interaction, indicated differential performance of genotypes over environments. Considering mean grain yield, and the Linear Regression parameters bi and S2d values jointly, the F1-hybrids 160×2, 160×3 and 6×3 gave above average mean of grain yield/ha and were most stable for grain yield/ha. AMMI analysis differentiated the genotypes (parental inbred lines and F1-hybrids), based on their grain yield, into different adaptation pattern and stability. Based on AMMI analysis, the F1- hybrids 66y×6 and 6×3 were highly stable with considerable high yield and adapted to favorable environments. However, the F1- hybrids 160×66y and 160×3 exhibited the highest mean grain yield/ha (4.1 tons and 3.5 tons, respectively), with slightly low interaction scores, hence they are regarded as superior hybrids.

5.
Br Biotechnol J ; 2011 Oct; 1(3): 68-84
Article in English | IMSEAR | ID: sea-162358

ABSTRACT

Aim: To determine the possible effects of environment and genotypic differences on root yield and other related traits. Methodology: 43 improved cassava genotypes were evaluated for root yield, root number, root dry matter, cassava mosaic disease and Cassava bacterial disease. The experiments were conducted using a randomized complete-block design with four replications for two years in three representative agro-ecological zones (Mokwa, Ibadan and Onne) in Nigeria. The data collected were subjected to combined analyses of variance using the GLM procedure of Statistical Analysis System (SAS 9.2) to determine the magnitude of the main effects and interactions. GGEbiplot software (GGEbiplot, 2007) was applied for visual examination of the GEI pattern of the data. Results: Genotype, Location and genotype by environment (GXE) interaction were highly significant for all the traits studied (P< 0.001), indicating genetic variability between genotypes by changing environments. The partitioning of GGE through GGE biplot analysis showed that PC1 and PC2 accounted for 61.3% and 28.8% of GGE sum of squares respectively for root yield, explaining a total of 90.1% variation. Conclusion: Genotypes G4 and G15 were the highest yielding and stable genotypes. G2 and G7 were equally stable but with poor roots yield. G43, which had a mean yield similar to the grand mean, may be regarded as a desirable genotype. Mokwa and Ibadan were found to be the most discriminative and the least representative environments for root yields while Onne environment was found to be the most representative and the least discriminative.

6.
Ciênc. rural ; 39(7): 1974-1982, out. 2009. tab, ilus
Article in Portuguese | LILACS | ID: lil-526747

ABSTRACT

O objetivo deste trabalho foi avaliar os componentes da variância fenotípica para o caráter rendimento de grãos a fim de gerar informações que auxiliem o melhoramento de plantas e verificar a sensibilidade genotípica entre genótipos de feijão do grupo preto. Para tanto, foi avaliado o caráter rendimento de grãos de 12 genótipos de feijão em 10 ambientes do Estado de Santa Catarina, por meio do método REML/BLUP. A decomposição dos componentes da variância fenotípica permitiu ampliar as inferências sobre os resultados obtidos para o caráter rendimento de grãos além daquelas tradicionalmente utilizadas na avaliação de linhagens. O genótipo BRS Campeiro foi o que apresentou maior média de rendimento de grãos e ainda o que obteve o maior valor predito, podendo ser indicado para todos ambientes avaliados. Nos ambientes 1 (2004/Canoinhas), 2 (2005/Canoinhas), 9 (2004/Ponte Serrada) e 10 (2005/Ponte Serrada), o valor de rendimento de grãos, em todos os genótipos avaliados, foi acima da média geral. Os genótipos CHP 9858, CHP 9859, CHP 9954 e CHP 9965 revelaram uma adaptabilidade específica ao ambiente 6 (2005/Ituporanga).


This study aimed to evaluate the phenotypic variance components for grain yield characters on the sense to be useful for breeding programs, and verify the genetic sensibilility among genotypes of black beans group. The grain yield character was evaluated in twelve black beans genotypes in ten environments of the Santa Catarina Estate through the REML / BLUP method. With the phenotypic variance components decomposition it was possible to provide additional information than traidicionally utilized in line evaluations for grain yield character. The highest grain yield average and the highest predicted value was obtain at genotype BRS Campeiro, which may be suitable for all evaluated environments. In the environments 1 (2004/Canoinhas), 2 (2005/Canoinhas), 9 (2004/Ponte Serrada) e 10 (2005/Ponte Serrada) higher grain yield has been obtained above general mean in all evaluated genotypes. The genotypes CHP 9858, CHP 9859, CHP 9954 and CHP 9965 presented specific adaptability to environment 6 (2005/Ituporanga).

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