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URI permanente para esta coleçãohttps://locus.ufv.br/handle/123456789/11845

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2010 - 201929

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Data inicial: 2010Data final: 2019Autor: search.filters.author.Cruz, Cosme Damião

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Agora exibindo 1 - 10 de 29
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    Valuation of methodologies for mapping oligogenic trait loci in Recombinant Inbred Lines (RILs)
    (Acta Scientiarum. Agronomy, 2014-01) Peixoto, Leonardo de Azevedo; Cruz, Cosme Damião; Silva, Marcia Flores ferreira da; Ferreira, Adésio
    The present work aimed to compare the efficiencies of the Oligogenic Trait Mapping Method (OTMM) and Interval Method (IM) for detecting oligogenic trait loci (OTL) in Recombinant Inbred Line (RIL) populations of different sizes. Populations consisting of 200, 500 and 1,000 individuals were employed and 100 repetitions performed for each population size. Four characteristics were evaluated: C1, determined by two genes with 50 and 30% effects on expression of the characteristic; C2, governed by three genes with 50, 20 and 10% effects; C3, regulated by two genes, each with 40% effect; and C4, controlled by two genes, each with 50% effect. The IM was efficient at detecting OTL in all evaluated characteristics; however, for characteristics determined by two genes with effects between 40 and 50%, the OTMM was more efficient at detecting and localizing OTL in simulated marks. In contrast, the IM method was more efficient at detecting and localizing OTL in simulated marks when the gene effect ranged from 10 to 30%. As a result, because oligogenic characteristics are governed by genes with greater effects, the OTMM was considered the most efficient method to be used for this type of characteristic.
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    Detection of QTL associated with rust resistance using IBD-based methdologies in exogamic Eucalyptus spp. populations
    (Crop Breeding and Applied Biotechnology, 2010-12) Rosado, Tatiana Barbosa; Tomaz, Rafael Simões; Ribeiro Junior, Marcio Fernandes; Guimarães, Lúcio Mauro da Silva; Araújo, Elza Fernandes de; Alfenas, Acelino Couto; Cruz, Cosme Damião; Rosado, Antônio Marcos
    In Brazil the rust caused by Puccinia psidii Winter stands out as the most important disease of eucalyptus. The use of resistant genotypes is the main control method, which makes the detection of markers linked to rust resistance essential to the selection of resistant genotypes. In this study, an F1 progeny of 131 plants from interspecific crossings of Eucalyptus was used to identify markers linked to resistance genes for this pathogen. An integrated map was constructed for linkage group three based on microsatellite markers. For QTL mapping two methodologies based on alleles identical-by-descent (IBD) were used: single marker analysis of Haseman and Elston and the interval mapping procedure of Fulker and Cardon. Both methods showed significant association for the Embra 125 marker.The QTL that explained 42 % of the phenotypic variation was mapped to 0.02 cM of this marker by the Fulker and Cardon. Marker Embra 125 has potential use in assisted selection, thus increasing the efficiency of the selection of resistant genotypes.
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    Validação e correção de fenótipos na seleção genômica ampla
    (Pesquisa Agropecuária Brasileira, 2016-12) Cruz, Cosme Damião; Almeida, Ísis Fernanda de; Resende, Marcos Deon Vilela de
    O objetivo deste trabalho foi avaliar a influência da distribuição dos efeitos de QTL, do tipo de população de validação e da correção dos fenótipos sobre a acurácia da seleção genômica ampla. Duas populações de irmãos completos, com 500 indivíduos, foram simuladas, tendo-se considerado, genotipicamente, 1.000 locos marcadores - 100 ligados a QTL. Os efeitos de QTL apresentaram distribuição uniforme ou exponencial. Na validação 1, uma amostra com 100 indivíduos constituiu a população de validação; na validação 2, aplicou-se a validação cruzada, com amostra de 100 indivíduos em cinco repetições; e na 3, uma segunda geração constituiu a população de validação. As metodologias de análise utilizadas foram RR-Blup e Blasso, com modelos mistos para correção dos fenótipos. Sem correção fenotípica, a distribuição exponencial proporcionou maiores acurácias, e o método Blasso foi mais acurado com essa distribuição; enquanto o RRBlup foi mais acurado com a distribuição uniforme. Nesse cenário sem correção, as validações 1 e 3 foram mais acuradas. Com correção, as distribuições exponencial e uniforme produziram acurácias similares, e o método Blasso mostrou-se mais acurado para ambas. Nesse cenário, as validações 1 e 2 foram mais acuradas. No geral, o método RR-Blup foi mais acurado, e o Blasso menos viciado.
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    Fuzzy control systems for decision-making in cultivars recommendation
    (Acta Scientiarum. Agronomy, 2018) Carneiro, Vinícius Quintão; Prado, Adalgisa Leles do; Cruz, Cosme Damião; Carneiro, Pedro Crescêncio Souza; Nascimento, Moysés; Carneiro, José Eustáquio de Souza
    The objective of the present study was to propose fuzzy control systems to support the recommendation of cultivars of different agronomic crops. Grain yield data from 23 lines and 2 cultivars of red bean were used to evaluate the applicability of these controllers. Genotypes were evaluated in nine environments in the Zona da Mata region, Minas Gerais State, Brazil. Using the parameters of Eberhart and Russell analysis, fuzzy controllers were developed with the Mamdani and Sugeno inference systems. Analyses of adaptability and stability were carried out by the method of Eberhart and Russell. The parameters obtained for each genotype were submitted to the respective controllers. There were significant genotypes x environments interaction, which justified the necessity of performing an adaptability and stability analysis. For both controllers (Mamdani and Sugeno), seven lines presented general adaptability, while only one presented adaptability to unfavorable environments. It was also found that both inference systems were useful for developing controllers that had the aim of recommending cultivars. Thus, it was noted that fuzzy control systems have the potential to identify the behavior of bean genotypes.
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    Self-organizing maps in the study of genetic diversity among irrigated rice genotypes
    (Acta Scientiarum. Agronomy, 2019-12) Santos, Iara Gonçalves dos; Carneiro, Vinícius Quintão; Silva Junior, Antônio Carlos da; Cruz, Cosme Damião; Soares, Plínio César
    This study presents self-organizing maps (SOM) as an alternative method to evaluate genetic diversity in plant breeding programs. Twenty-five genotypes were evaluated in two environments for 11 phenotypic traits. The genotypes were clustered according to the SOM technique, with variable topology and numbers of neurons. In addition to the SOM analysis, unweighted pair group method with arithmetic mean clustering (UPGMA) was performed to observe the behavior of the clustering when submitted to these techniques and to evaluate their complementarities. Genotype ordering according to SOM was consistent with UPGMA results, evidenced by the basic structure of UPGMA groups being preserved in each group of the maps. Regarding genotype arrangement and the group neighbors, maps involving five neurons presented inferior organization efficiency compared to the six-map arrangements in both environments. It was observed that the organization pattern among the rice genotypes evaluated by the maps was complementary to the UPGMA approach, as observed in all scenarios. It can be concluded that self-organizing maps have the potential to be useful for genetic diversity studies in breeding programs.
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    Avaliação de metodologias de adaptabilidade e estabilidade de cultivares milho
    (Acta Scientiarum. Agronomy, 2011-01) Cruz, Cosme Damião; Schmildt, Edilson Romais; Nascimento, Adriel Lima; Oliveira, Jaqueline Aparecida Raminelli
    Este trabalho objetivou comparar três metodologias para análise de adaptabilidade e estabilidade de produtividade. Foi avaliada a produtividade de cultivares de milho do ensaio nacional da Embrapa, centro, nas safras agrícolas 2004/2005, 2005/2006 e 2006/2007, determinando-se a adaptabilidade e estabilidade pelos métodos de Lin e Binns com decomposição (CRUZ; CARNEIRO, 2006); Annicchiarico com decomposição (SCHMILDT; CRUZ, 2005) e um método proposto baseado no método de Annicchiarico com decomposição. Foram propostos a utilização do erro-padrão da média ao invés do desvio-padrão, no cálculo da variabilidade dos ambientes para cada cultivar e também o aumento do nível de confiança, de 75 para 95%. Percebeu-se que os resultados de indicação de cultivares pelos três métodos apresentaram alta correlação de Spearman (p < 0,01). A metodologia proposta, apresenta as vantagens de valorizar mais os desvios apresentados entre os ambientes, por levar em consideração o número de ambientes e também por apresentar menor nível de significância, possibilitando menor erro do tipo I. A metodologia proposta apresenta os resultados numéricos do índice de confiança de mesmo valor que os resultados do método de Annicchiarico com decomposição quando o número de ambientes em comparação for igual a seis.
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    Genetic diversity among accessions of sacha inchi (Plukenetia volubilis) by phenotypic characteristics analysis
    (Acta Amazonica, 2018-04) Rodrigues, Haroldo Silva; Borém, Aluízio; Valente, Mágno Sávio Ferreira; Lopes, Maria Teresa Gomes; Cruz, Cosme Damião; Chaves, Francisco Célio Maia; Bezerra, Caroline de Souza
    Sacha inchi (Plukenetia volubilis) is native to the Amazon region and has a high seed content of mono and polyunsaturated fatty acids, making it interesting for the pharmaceutical and cosmetic industry. The purpose of this study was to analyze the genetic diversity and describe the accessions based on phenotypic characteristics. Fruits and seeds of 25 accessions from the sacha inchi genebank of Embrapa Amazônia Ocidental in Manaus, Amazonas state, were sampled and biometrically measured. The data were subjected to analysis of variance, Mahalanobis distance, canonical correlation, and genetic diversity among and within by analysis of molecular variance (AMOVA). There were significant differences among the means of the analyzed traits, but no significant canonical correlation for the groups of traits. According to AMOVA, approximately 60% of the observed variation is within accessions. The results showed variability among accessions and that the variation within accessions should be explored to obtain best results in breeding programs.
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    Método para mapeamento de locos controladores de características oligogênicas
    (Ciência Rural, 2010-02) Rocha, Rodrigo Barros; Barros, Willian Silva; Muro-Abad, Júpiter Israel; Tomaz, Rafael Simões; Cruz, Cosme Damião; Barros, Everaldo Gonçalves de; Araújo, Elza Fernandes de
    Características oligogênicas de distribuição discreta e expressão governada por poucos genes de maior efeito têm se mostrado importantes na condução dos programas de melhoramento, com destaque para a resposta de resistência das plantas às doenças. Métodos tradicionais de detecção de QTL’s, que pressupõem normalidade e herança governada por múltiplos fatores, não deveriam ser utilizados para mapeamento dessas características de distribuição discreta e interação epistática predominante. O objetivo deste trabalho é avaliar os resultados de um método para mapeamento e detecção de locos controladores da expressão de características oligogênicas, OTL’s (Oligogenic Trait Loci). Esse método, definido como MMCO (Método de Mapeamento de Características Oligogênicas), utiliza funções de verossimilhança para obtenção de estimativas de ligação fatorial entre locos marcadores e locos controladores de características oligogênicas. Os resultados indicam que o método foi adequado para detecção de OTL’s em populações F2 relativamente pequenas, compostas por 200 indivíduos, e que a determinação a priori do padrão de herança é condição necessária para a utilização dessa estratégia, que se diferencia por atender as pressuposições de análise, não necessitar de informação prévia de ordenamento entre as marcas e por permitir a obtenção de estimativas a partir da informação contida em todas as classes genotípicas.
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    Direct, indirect and simultaneous selection as strategies for alfalfa breeding on forage yield and nutritive value
    (Pesquisa Agropecuária Tropical, 2018-04) Santos, Iara Gonçalves dos; Cruz, Cosme Damião; Nascimento, Moysés; Rosado, Renato Domiciano Silva; Ferreira, Reinaldo de Paula
    Alfalfa breeding aimed at trait improvement for livestock feed takes longer periods of time, if compared to many other crops. Therefore, better selection methods are necessary for the success of alfalfa breeding programs. Although knowing about selection methods is quite important, there is a notable lack of information, as regards successful solutions. This study aimed to use direct, indirect and simultaneous selection methods for selecting alfalfa cultivars, based on yield traits and nutritive value. The evaluated traits were subdivided into two groups: forage yield and nutritive value. Selection gains were estimated by direct, indirect and simultaneous selection for each group, considering the selection of the 25 % best cultivars. Direct and indirect selections among genotype averages are not efficient to provide the desirable responses to the whole set of traits. The results for simultaneous selection, using the Tai index, provided a more balanced gain distribution to the set of traits in all cuts. The simultaneous selection allowed the identification of the 5681 and Verdor cultivars in the first cut, as well as ProINTA Patricia in the second cut, as superior in the two groups of evaluated traits.
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    Quantile regression for genome-wide association study of flowering time-related traits in common bean
    (Plos One, 2018) Nascimento, Moysés; Nascimento, Ana Carolina Campana; Silva, Fabyano Fonseca e; Barili, Leiri Daiane; Vale, Naine Martins do; Carneiro, José Eustáquio; Cruz, Cosme Damião; Carneiro, Pedro Crescêncio Souza; Serão, Nick Vergara Lopes
    Flowering is an important agronomic trait. Quantile regression (QR) can be used to fit models for all portions of a probability distribution. In Genome-wide association studies (GWAS), QR can estimate SNP (Single Nucleotide Polymorphism) effects on each quantile of interest. The objectives of this study were to estimate genetic parameters and to use QR to identify genomic regions for phenological traits (Days to first flower—DFF; Days for flowering—DTF; Days to end of flowering—DEF) in common bean. A total of 80 genotypes of common beans, with 3 replicates were raised at 4 locations and seasons. Plants were genotyped for 384 SNPs. Traditional single-SNP and 9 QR models, ranging from equally spaced quantiles (τ) 0.1 to 0.9, were used to associate SNPs to phenotype. Heritabilities were moderate high, ranging from 0.32 to 0.58. Genetic and phenotypic correlations were all high, averaging 0.66 and 0.98, respectively. Traditional single-SNP GWAS model was not able to find any SNP-trait association. On the other hand, when using QR methodology considering one extreme quantile (τ = 0.1) we found, respectively 1 and 7, significant SNPs associated for DFF and DTF. Significant SNPs were found on Pv01, Pv02, Pv03, Pv07, Pv10 and Pv11 chromosomes. We investigated potential candidate genes in the region around these significant SNPs. Three genes involved in the flowering pathways were identified, including Phvul.001G214500, Phvul.007G229300 and Phvul.010G142900.1 on Pv01, Pv07 and Pv10, respectively. These results indicate that GWAS-based QR was able to enhance the understanding on genetic architecture of phenological traits (DFF and DTF) in common bean.