Antonio Costa de Oliveira

Federal University of Pelotas | UFPEL · Department of Plant Sciences

A toxicidade do alumínio é um dos principais fatores limitantes do desenvolvimento das plantas em solos ácidos. Pelo fato da utilização de corretivos da acidez do solo não ser a estratégia mais viável em muitas situações com solos ácidos (por razões técnicas e econômicas), o desenvolvimento de genótipos tolerantes ao Al tem sido o caminho mais foca...

The present research was aimed at verifing the effect of different periods of ultraviolet light on the development of the symbiont fungus of leaf cutting ants belonging to the species Acromyrmex ambiguus, Acromyrmex crassispinus and Acromyrmex lundi, through the AFLP technique. The fungus were inoculated in Pagnocca's medium and maintained in clima...

O presente trabalho teve por objetivo verificar o efeito de diferentes períodos de luz ultravioleta sobre a similaridade genética do fungo simbionte de formigas cortadeiras pertencentes às espécies Acromyrmex ambiguus, Acromyrmex crassispinus e Acromyrmex lundi, através da técnica AFLP. Os fungos foram inoculados em meio de cultura Pagnocca e manti...

At present, a few number of taxonomists work on identification of leaf cutting ants. Morphological-based methods do not always produce a reliable identification, due to the strong polymorphism observed even in the same colony. This fact leads to hypothesize that, besides those variations, others may also occur related to geographic distribution of...

O aumento na eficiência de seleção, o melhor conhecimento e caracterização do germoplasma e a maximização dos ganhos genéticos, têm sido objetivos dos melhoristas de plantas do mundo inteiro. Novas estratégias para alcançar estes objetivos são constantemente implementadas pelo melhoramento de plantas. Os marcadores moleculares oferecem ao melhorist...

Os caracteres fenotípicos e as informações genealógicas se destacam entre as ferramentas possíveis de serem utilizadas pelos melhoristas na obtenção de estimativa da distância genética entre e dentro das espécies vegetais. Deste modo, o objetivo do trabalho foi estimar a distância genética entre genótipos de trigo sul-brasileiros, por meio do empre...

Maize could be an excellent option for crop rotation in flooded areas in southern Brazil. There are, however, few studies on the genetic basis of tolerance to flooding in maize. The objective of this study was to determine the inheritance of this tolerance based on plant and root dry matter of young maize plants. Maize lines were crossed to form th...

Increase in selection efficiency, the best knowledge and characterization of the germplasm and maximization of the genetic gains, have been objectives of plant breeders worldwide. New approaches to reach these objectives are constantly implemented by breeding programs. Molecular markers allow the breeder to assess individual genotypes instead of ju...

The objective of this research was to compare the consistency of the bi-segmented and AMMI (additive main effects and multiplicative interaction analysis) methods for estimating yield stability in potatoes. Data of ten genotypes evaluated in 34 environments (local, growing season and year combinations) of the Rio Grande do Sul state, Brazil, in 199...

O melhoramento de plantas tem por base a ampliação da variabilidade genética existente através de cruzamentos artificiais planejados. Assim, é de fundamental importância o conhecimento das populações formadas, a fim de prever o potencial das combinações a partir de diferentes genitores, permitindo maior eficiência de seleção para o caráter desejado...

Plant breeding is based on the pursue of an amplification of genetic variability through planned crosses. Thus, it is of fundamental importance to study the formed populations, in order to predict the potential of different parental combinations, allowing a higher selection efficiency for the desired trait, optimizing genetics gains. Thus, the obje...

Aluminum toxicity is one of the major limiting factor regarding plant development in acid soils. The use of liming for correcting soil pH is not viable for some of acid soil areas (technique or economic reasons), making the development of Al tolerant genotypes the best alternative. Thus, the tolerance mechanisms as well as the genetic basis of Al t...

The objective of this study was to evaluate the response of 30 mutant oat lines to the phytotoxic action of organic acids produced in the soil. In a hydroponic system with three treatments (0,7 and 10 mM) the variables root (CR) and shoot (CPA) length; number of roots (NR) and root dry matter (MSR) were measured. Only CPA at a dose of 7 mM was not...

Minimal population size is a major question in plant breeding programs and it is dependent on many factors such the population under evaluation, target trait, environmental conditions and the level of wanted precision. Since financial and physical resources are always scarce in breeding programs, scientific studies regarding population size became...

A ocorrência de condições anaeróbias nos solos hidromórficos, associada com a presença de matéria orgânica favorece o desenvolvimento de microrganismos anaeróbios que produzem substâncias fitotóxicas, principalmente ácidos orgânicos de cadeia curta. A seleção de constituições genéticas de arroz promissoras para utilização nestas situações requer av...

The occurrence of anaerobic conditions in hydromorphic soils, associated with the presence of organic matter favors the development of anaerobic microorganisms that produce phytotoxic substances, especially short chain organic acids. Selection of promising rice genotypes for use under these conditions requires difficult field evaluations, which may...

Molecular and morphological data analyses matrices are very informative tools for the estimation of genetic distances. We used AFLP markers, morphological traits and combined analysis to estimate the genetic distances between wheat genotypes and ascertain any associations between the two techneques. Nineteen wheat (Triticum aestivum L.) genotypes w...

We present here the annotation of the complete genome of rice Oryza sativa L. ssp. japonica cultivar Nipponbare. All functional annotations for proteins and non-protein-coding RNA (npRNA) candidates were manually curated. Functions were identified or inferred in 19,969 (70%) of the proteins, and 131 possible npRNAs (including 58 antisense transcrip...

A brusone é a principal doença da cultura do arroz irrigado e pode comprometer até 100% da produção de grãos de algumas lavouras isoladas nos casos de ataques epidêmicos. A melhor forma para o controle desta doença é o emprego da resistência genética, por ser mais econômica. O trabalho teve por objetivo avaliar a herdabilidade, número de genes e aç...

Rice blast poses the greatest disease threat to irrigated rice, causing losses up to 100% in grain yield under epidemic attack. Genetic resistance is the most effective and environmentally sound way to control the disease. Thus, the objective of this work was to evaluate the number of genes and gene action involved in the inheritance of resistance...

Rice is a model genome for cereal research, providing important information about genome structure and evolution. Retrotransposons are common components of grass genomes, showing activity at transcription, translation and integration levels. Their abundance and ability to transpose make them good potential markers. In this study, we used 2 multiloc...

TOLERANCE TO THE ALUMINUM IN OAT CULTIVARS UNDER HYDROPONIC CULTURE The use of hidroponic culture to evaluate tolerance to aluminum toxicity in oat genotypes can be performed by measuring root regrowth, allowing phenotypically to discriminate tolerant genetic constitutions sensitivity. Twelve white oat cultivars indicated for cultivation in Souther...

Using isolates collected in three counties of Rio Grande do Sul State, Brazil, the goals of this work were to determine (i) the pattern of virulence or avirulence of the isolates to 25 Pc resistance genes, (ii) the similarity in virulence among Puccinia coronata f. sp. avenae isolates considering their pattern of virulence or avirulence, (iii) the...

Conhecer como os caracteres agronômicos se correlacionam nas populações segregantes é primordial ao melhorista de plantas, principalmente quando o objetivo for seleção indireta, por meio de um caráter de fácil mensuração ou de maior herdabilidade correlacionado ao caráter de interesse de menor herdabilidade. Dessa forma, a partir da variabilidade o...

As temperaturas baixas que ocorrem durante o cultivo do arroz na Região Sul do Brasil causam prejuízos ao rendimento e à qualidade dos grãos de arroz. Genótipos tolerantes a baixas temperaturas seriam uma alternativa para minimizar tais prejuízos. Desse modo, o presente trabalho teve como objetivo avaliar a tolerância ao frio em famílias mutantes d...

Selection of the appropriate parents to be used in artificial crosses is one of the main decisions faced by plant breeders that will facilitate the exploitation of maximum genetic variability and production of superior recombinant genotypes. Several techniques have been used in aiding the identification of genotypes with promising and desirable agr...

Maize could be an excellent option for crop rotation in flooded areas in southern Brazil. There are, however,few studies on the genetic basis of tolerance to flooding in maize. The objective of this study was to determine the inheritanceof this tolerance based on plant and root dry matter of young maize plants. Maize lines were crossed to form thre...

Em trigo a distância genética vem sendo estimada por meio de caracteres fenotípicos, dados moleculares, coeficiente de parentesco e a combinação destes. Entretanto, não existem estudos comparando a distância estimada a partir de caracteres morfológicos e fenológicos acessados a campo, a partir de caracteres fenotípicos relacionados à produtividade...

The use of hidroponic culture to evaluate tolerance to aluminum toxicity in oat genotypes can be performed by measuring root regrowth, allowing phenotypically to discriminate tolerant genetic constitutions sensitivity. Twelve white oat cultivars indicated for cultivation in Southern Brazil were evaluated aiming at to characterize their aluminum tol...

The knowledge of how the agronomical traits are correlated in segregating populations is of primary importance for plant breeders, specially when one considers indirect selection through a character easily measurable or with high heritability correlated to the trait of interest with lower heritability. Agronomical traits in F2 and F3 generations of...

Low temperatures that occur during the cultivation of rice in the Southern region of Brazil cause reductions in to the yield and quality of the rice grain. Genotypes tolerant to low temperatures would be an alternative to minimize these problems. In the present work cold tolerance was evaluated in rice families (M4 generation) in the vegetative and...

This research was aimed at evaluating and identifing which type of sum of squares can be more appropriate to test hypotheses and also presenting appropriate alternatives to solution of problems through the analysis of mean square expected values used in the methodology of mixed linear models. The analysis of mean square expected values can be a too...

The objective of this work was to develop the use of backcrosses among elite parental lines and to identify the parents with higher probability of developing superior progenies when used in crossing blocks. The following traits were analyzed: number of panicles per plant and plant grain yield in kg. ha-1. Five oat genotypes (UPF 16, UPF 18, UFRGS 7...

O objetivo deste trabalho foi estimar a utilização do método de retrocruzamento entre genitores elite para obtenção de maior probabilidade de desenvolver progênies superiores de aveia que propiciem elevado êxito na seleção. Foram coletados dados dos caracteres: número de panículas por planta e rendimento de grãos da planta individual em kg ha-1. Fo...

The objectives of the present work were to adjust the method for identifying genetic variability in rice through the use of minimal solution in hydroponic culture, and to identify the most important level and character for the study. The experiment consisted of the response evaluation of 18 rice genotypes to three levels of aluminum treatment. Five...

The aim of the study was to evaluate the efficiency of three methods of cluster analysis in representing the estimated genetic distance through morphological traits among 19 genotypes of wheat and to evaluate a selection index of parents based on the distance in relation to the ideotype. The experiment was carried out in 2003 and 2004, at the UFPEL...

O conhecimento da distância genética entre genótipos é importante ferramenta utilizada na escolha de genitores que vão dar origem às populações segregantes. Essa informação serve como parâmetro para indicação de cruzamentos que possibilitem recuperar recombinantes superiores para o caráter desejado. O principal objetivo do estudo foi promover infor...

The objective was to evaluate wheat near-isogenic lines differing from the trait stay-green and synchronized maturation regarding their alluminum tolerance and sensibility to the giberellic acid (GA3). The experiment was conducted in the Double-haploids and Hydroponics Laboratory of FAEM/UFPel, in random block with split plot design with three repl...

A seleção indireta visando ao incremento no rendimento de grãos pelos seus componentes primários bem como a resistência ao acamamento podem representar estratégias eficientes a serem adotadas para otimização do ganho genético em trigo. Nesse sentido, o objetivo do trabalho foi evidenciar caracteres que possibilitem identificar genótipos de elevado...

O objetivo deste trabalho foi avaliar linhas quase isogênicas de trigo com o caráter permanência verde e de maturação sincronizada quanto à tolerância ao alumínio e à sensibilidade ao ácido giberélico (AG3). O experimento foi conduzido no Laboratório de Duplo-haplóides e Hidroponia da FAEM/UFPel, em delineamento de blocos ao acaso, com parcelas sub...

Resumo – O objetivo deste trabalho foi avaliar o efeito da dissimilaridade genética, aferida por caracteres morfológicos e marcadores moleculares, sobre a heterose e heterobeltiose em híbridos de aveia. Foram utilizados cinco genitores cruzados na forma dialélica, tendo sido desconsiderados os híbridos recíprocos. Não houve relação linear entre as...

Resumo – Os objetivos deste trabalho foram: determinar o padrão de resistência/suscetibilidade de 20 genótipos de aveia a 40 isolados de Puccinia coronata f. sp. avenae, coletados em três municípios do Rio Grande do Sul; o padrão de virulência/avirulência desses isolados contra os genótipos de aveia; e indicar genitores para a geração de populações...

The objective of this work was to assess genetic dissimilarity effect, as determined by morphological traits and molecular markers, on heterosis and heterobeltiosis in oat hybrids. Five parent lines were crossed in a diallelic design, disregarding reciprocal hybrids. Nolinear relationship among means of genetic dissimilarity was established, possib...

The objectives of this work were: to determine the resistance/susceptibility pattern of 20elite oat genotypes to 40isolates of Puccinia coronata f.sp. avenae; to determine the pattern of virulence/avirulence of isolates collected in three counties of Rio Grande do Sul to the oat genotypes studied; and to indicate potential parents for the generatio...

In Brazil, oat is cultivated over a vast area. There are, however, no reports on the use of the different traits of importance measured simultaneously in different environments for cultivar classification. The objective of our study was to compare nonparametric selection indexes for cultivar classification in their average performance in six enviro...

Oat crown rust is the most important disease for the oat crop, occurring in practically all the areas where oat is cultivated. The most indicated form of control for this disease is the use of resistant cultivars. However, for the durable resistance to be acquired, it is necessary to know the genetics of resistance to crown rust in oats. Thus, the...

Panicle weight selection in oats is a potential tool for indirect selection for grain yield. However, the phenotype depends on the expression of several genes, hindering the selection based on traditional methods. The identification of markers associated to the trait has a lot to contribute for the development of Marker Assisted Selection programme...

Soils with high aluminum (Al3+) concentrations can affect the development and nutrient absorption of rice plants. The goals of this study were to evaluate the absorption of P, Mg, Ca and K in 18 rice genotypes and their overall performance when subjected to Al3+ stress in hydroponic systems. The experimental design was randomized blocks with 3 repl...

Solos com concentrações elevadas de alumínio (Al3+), podem prejudicar o desenvolvimento e a absorção de nutrientes de plantas de arroz. O objetivo do experimento foi avaliar o desempenho de dezoito genótipos de arroz quanto a absorção de P, Mg, Ca e K e identificar genótipos com bom desempenho quando submetidos ao estresse por Al3+ em sistema hidro...

A ferrugem da folha da aveia é a moléstia mais importante que ataca a cultura da aveia, ocorrendo em praticamente todas as áreas em que a aveia é cultivada. A forma mais indicada para o seu controle é a utilização de cultivares resistentes. Contudo, para que seja alcançada a resistência durável ao patógeno, é necessário que se conheça a genética da...

Indirect selection through traits of higher heritability and of case measurements can result in larger genetic progress compared to using direct selection. This work was performed with the following objectives: (1) to estimative the phenotypic correlations between individual plant grain yield and agronomic traits of importance in the selection of w...

Várias técnicas vêm sendo propostas para elevar a probabilidade de obtenção de populações segregantes promissoras, concentrando grande esforços dos pesquisadores. Assim, o objetivo deste trabalho foi verificar a eficiência da utilização da média dos genitores, da heterose e heterobeltiose do F1 e da distância genética morfológica e molecular na pre...

O conhecimento da distância genética entre genótipos é importante ferramenta utilizada na escolha de genitores que vão dar origem às populações segregantes. Essa informação serve como parâmetro para indicação de cruzamentos que possibilitem recuperar recombinantes superiores para o caráter desejado. O principal objetivo do estudo foi promover infor...

Estudos de diversidade e estrutura genética de populações de patógenos por meio de genes de resistência conhecidos são importantes, por permitirem o acesso de forma direta aos genes de virulência/avirulência dos indivíduos das diferentes populações-alvo. Dessa forma, o objetivo deste trabalho foi caracterizar a diversidade e a estrutura genética de...

In oat (Avena sativa L.) breeding programs, the advance of segregating generations demands physical, financial and humans resources. However, an effective process of selection by characters highly correlated can facilitate the success of plant breeders in obtaining genetic constitutions with high performance in early generations. Five oat genotypes...

RESUMO O cultivo hidropônico permite avaliar a tolerância de genótipos de aveia à toxicidade ao alumínio por meio da medida da retomada do crescimento de raiz, separando fenotipicamente, os genótipos como tolerantes e sensíveis. Dez cultivares de aveia branca recomendadas para o cultivo no Sul do Brasil foram avaliados para quantificar a tolerância...

Rice is a major worldwide-cultivated crop. Besides it's the economical and social importance, this species have biological features that make it a model for basic studies. In the last years at least three sequencing project were announced generating valuable information. Mutants may be a powerful tool to study gene action, function and regulation....

A dissimilaridade genética estimada por meio de marcadores moleculares, quando acompanhada de informações fenotípicas, é importante para a seleção de genótipos para o melhoramento e o mapeamento genético. Desta forma, os objetivos deste estudo foram: i) estimar a dissimilaridade genética entre 30 linhagens de milho contrastantes para a tolerância a...

A dissimilaridade genética estimada por meio de marcadores moleculares, quando acompanhada de informações fenotípicas, é importante para a seleção de genótipos para o melhoramento e o mapeamento genético. Desta forma, os objetivos deste estudo foram: i) estimar a dissimilaridade genética entre 30 linhagens de milho contrastantes para a tolerância a...

In genetics and breeding studies it is common to conduct experiments of fixed (sowing method) and random (populations) factors. Therefore, the most appropriate statistic analyses would use mixed linear models. In this sense, objectives of this work were i) to estimate the variance components for the random factor effects and interaction population...

Rice, one of the world's most important food plants, has important syntenic relationships with the other cereal species and is a model plant for the grasses. Here we present a map-based, finished quality sequence that covers 95% of the 389Mb genome, including virtually all of the euchromatin and two complete centromeres. A total of 37,544 nontransp...

Rice, one of the world's most important food plants, has important syntenic relationships with the other cereal species and is a model plant for the grasses. Here we present a map-based, finished quality sequence that covers 95% of the 389 Mb genome, including virtually all of the euchromatin and two complete centromeres. A total of 37,544 non-tran...

Several studies have searched for higher efficiency on plant selection in generations bearing high frequency of heterozygotes. This work aims to compare the response of direct selection for grain yield, indirect selection through average grain weight and combined selection for higher yield potential and average grain weight of oat plants (Avena sat...

Demands for sustainable agricultural systems have forested the development of biological control techniques, such as the use of the egg parasitoid Trichogramma Westwood. However, the arduous identification of the parasitoid at the species level, due to the tiny size and the morphological similarities is an obstacle to increasing its use. Molecular...

Estimates of associations among traits are not very precise when based on annual data since the year factor influence the phenotype strongly. Therefore, objective of this work was to estimate the repeatability coefficients and number of years needed for an accurate prediction of genetic, phenotypic and environmental correlations among six important...

Objective of this work was to estimate genetic parameters among and within potato clonal families for tuber yield, average tuber weight, tuber appearance and chip color. Twenty families were evaluated in spring 2003 and fall 2004 on the experimental field of Embrapa Clima Temperado, Pelotas, state of Rio Grande do Sul, Brazil. A randomized complete...

In genetics and breeding studies it is common to conduct experiments of fixed (sowing method) and random (populations) factors. Therefore, the most appropriate statistic analyses would use mixed linear models. In this sense, objectives of this work were i) to estimate the variance components for the random factor effects and interaction population...

A correlação genotípica permite avaliar a magnitude e a direção da associação entre caracteres, sendo de grande utilidade por permitir a viabilidade do emprego da seleção indireta, que em alguns casos, pode levar a progressos genéticos mais rápidos e altamente expressivos em programas de melhoramento de aveia (Avena sativa L.). O objetivo deste tra...

The use of genotypic correlation helps evaluating the magnitude and direction of associations between characters facilitating the application of indirect selection, leading to faster and larger genetic gains in oat (Avena sativa L.) breeding programs. This study aimed to test a modification of PETR & FREYS’ (1996) formula, to obtain genotypic, phen...

Phenotype-based selection can be influenced by environmental factors. Plants breeders need to use selection methods to separate genetic from environmental effects. The goal of this study was to test the efficacy of indirect selection to increase oat (Avena sativa L.) grain yield under different sowing systems. Eight oat segregant populations were s...

Twenty oat genotypes (Avena sativa L.) were evaluated for grain yield in the crop year of 2001 and 2002 in nine different locations in Paraná, Rio Grande do Sul and São Paulo states, Brazil. The objectives of this work were to obtain adaptability and stability parameters estimates in favorable and unfavorable environments with and without fungicide...

The statistical multivariate analysis has a widespread use by researchers, creating a large demand for specific knowledge regarding its application concerning its assumptions and or limitations. In order to evaluate the degree of association among different characters of agronomic importance with an estimative reliable in biological terms, it is st...

A seleção com base no fenótipo pode ser influenciada por fatores de ambiente, sendo necessário que o melhorista utilize métodos de seleção que separem efeitos genéticos dos de ambiente. O objetivo deste estudo foi testar a eficiência da seleção indireta para o incremento no rendimento de grãos de aveia (Avena sativa L). Oito populações segregantes...

Vinte cultivares de aveia (Avena sativa L.) foram avaliados para rendimento de grãos nas safras agrícolas de 2001 e 2002 em nove locais dos estados do Paraná, Rio Grande do Sul e São Paulo, com o objetivo de avaliar as estimativas dos componentes de adaptabilidade e estabilidade do rendimento de grãos em ambientes favoráveis e desfavoráveis em pres...

A análise estatística do tipo multivariada vem crescendo consideravelmente, motivando a sua ampla utilização por parte dos pesquisadores criando, assim, grande demanda por conhecimentos específicos tanto a respeito da sua aplicação quanto das suas pressuposições ou limitações. Para que a avaliação do grau de associação entre diferentes caracteres d...

Knowledge on the inheritance of lodging-resistance is of great value for the development of new wheat varieties (Triticum aestivum L.). Crosses among four different bread wheat genotypes were evaluated in the field. The analysis was based on three fixed (P 1 , P 2 and F 1) and three segregant (F 2 , BC 1 F 1 and BC 2 F 1) generations. Means and var...

This study aimed to estimate the general (GCA) and specific (SCA) combining abilities and to provide genetic information related to the yield components through diallelic crosses involving five oat parents, analyzed by the method 2, model B, described by GRIFFING (1956). The experiment was conducted in the Centro Agropecuário da Palma. The followin...