ABSTRACT. The fungus Pseudocercospora griseola, the causal agent of angular leaf spot in the common bean (Phaseolus vulgaris L.), exhibits a broad pathogenic variability that complicates the development of resistant cultivars. For breeding programs to successfully obtain common bean cultivars with durable resistance, knowing the aggressiveness of different strains, as well as the mechanisms of genetic resistance, is important. The aims of this study were to study the variation within race 63.63 by evaluating the aggressiveness of different strains, to analyze the genetic resistance of common bean lines to P. griseola, and to ascertain the implications for genetic improvement in obtaining resistance in this pathosystem. Four strains, collected from different locations, were inoculated in three groups of common bean lines in a greenhouse, and the severity of the disease was subsequently evaluated. Statistical analyses were carried out using the diallel method, which provided information on the vertical and horizontal resistance of host plants, in addition to information 5045 Variability in strains of Pseudocercospora griseola ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 14 (2): 5044-5053 (2015) regarding the aggressiveness of the strains. The aggressiveness of P. griseola differed between the strains of race 63.63. The diallel method proved to be promising for the identification of horizontal and vertical resistance in the common bean-P. griseola pathosystem, with a predominance of horizontal resistance. Gene pyramiding, using marker-assisted selection, may not be the most effective strategy for obtaining durable resistance.
The aim of this study was to develop a diagrammatic scale to evaluate angular leaf spot (ALS) severity in primary leaves of common bean. A diagrammatic scale was developed and validated with nine levels of severity: 0 %; 0.1 to 0.5 %; 0.6 to 4.0 %; 4.1 to 7.0 %; 7.1 to 16 %; 16.1 to 26 %; 26.1 to 32 %; 32.1 to 38 % and 38.1 to 60 %. The use of this scale, associated with the early inoculation method, allowed rating of ALS severity in common bean leaves in the V2 stage of development that is, when the primary leaves are fully open. Validation of the scale was performed by 14 Evaluators. These Evaluators estimated the severity in 40 common bean leaves with different levels of severity, previously measured by the software Quant®. The accuracy and precision of each Evaluator were determined by simple linear regression, by comparing between actual severity, measured electronically, and that estimated by the Evaluator. Without the scale, most of the Evaluators overestimated the severity of the disease. With the scale, the Evaluators obtained better levels of accuracy and precision, with absolute errors less than 5 %. The diagrammatic scale proposed proved to be adequate for early performance of the pathogenicity test.
Phenotyping for severity of angular leaf spot (ALS) in common bean is important to identify new sources of resistance and select progenies in conventional and molecular markerassisted breeding. In this study, three phenotyping methods for ALS severity were assessed and its implications in breeding for resistance to Pseudocercospora griseola are discussed. Reaction of 144 common bean lines to P. griseola was evaluated. Three different experiments were conducted in the greenhouse (V2 and V3 stages) and in the field. Common bean lines were inoculated with a mixture of spores of pathogen races 63-63 and 63-23. We observed that 31 %, 7 % and 10 % of lines were resistant in stages V2, V3 and in the field, respectively. Estimates of coincidence index V2-V3, V2-field and V3-field were 68 %, 69 % and 88 %, respectively. Evaluations in V3 stage and in the field were the phenotyping methods more efficient for ALS severity. However, evaluation in V3 stage is impracticable to assess routinely many genotypes in breeding programs. Evaluation in V2 stage may be used to carry out a first screening, especially in the early stages of breeding programs. Moreover, this methodology may be used in association with evaluation of plants in the field to increase genetic gain.
Physiological quality and expression of genes in seeds ofHandroanthus serratifolius subjected to drying ABSTRACT -Handroanthus serratifolius seeds are considered orthodox and have some mechanisms that assist in desiccation tolerance, like heat-resistant proteins and the presence of protective systems against free radical production. In order to investigate the drying effect on the quality of Handroanthus serratifolius seeds collected with 28% water content two methods were used: slow drying (30 °C) and fast drying (45 °C) until water contents equaled 20%, 15%, 10% and 5%. Seed quality was assessed by germination test, first count of germination, speed germination, emergence and speed emergence. The expression of heat-resistant proteins and enzymes catalase, esterase and isocitrate lyase was assessed by electrophoresis. The gene expression of sHSP17.5, CAT3 and ICL6 was quantified by real time PCR. Higher values of germination and vigor were obtained in seeds with 20% water content, subjected to fast drying. There was induction of heat-resistant proteins expression for both drying methods. There was variation in the electrophoretic pattern of catalase, esterase and isocitrate lyase in seeds subjected to different treatments. The gene expression in Handroanthus serratifolius seeds varies depending on methods of drying and water content of seeds. The drying of Handroanthus serratifolius seeds until the water content between 15 and 10% compromises their physiological quality. Index terms: isoenzymes, enzymes, qRT-PCR, Handroanthus serratifolius.Qualidade fisiológica e expressão de genes em sementes de Handroanthus serratifolius submetidas à secagem RESUMO -Sementes de ipê-amarelo são consideradas ortodoxas e dispõem de mecanismos que auxiliam na tolerância à dessecação, como proteínas resistentes ao calor e sistemas de proteção contra radicais livres. Para investigar o efeito da secagem na qualidade das sementes de ipê-amarelo coletadas com 28% de teor de água utilizaram-se dois métodos: secagem lenta (30 ºC) e secagem rápida (45 ºC) até atingirem teores de água na massa de sementes iguais a 20%, 15%, 10% e 5%. A qualidade das sementes foi avaliada por meio de testes de germinação e vigor. Foi avaliada a expressão das proteínas resistentes ao calor e das enzimas catalase, esterase e isocitrato liase. A expressão dos genes sHSP17.5, CAT3 e ICL6 foi quantificada por meio da técnica de qRT-PCR. Maiores valores de germinação e vigor foram obtidos em sementes com teor de água de 20%, submetidas à secagem rápida. Houve a indução de expressão de proteínas resistentes ao calor nos dois métodos de secagem. Ocorreu variação no padrão eletroforético das enzimas catalase, esterase e isocitrato liase entre os diferentes tratamentos. A expressão de genes varia em função dos métodos de secagem e teores de água das sementes. A secagem até os teores de água entre 15 e 10% compromete a qualidade fisiológica das mesmas.Termos para indexação: isoenzimas, enzimas, RTqPCR, ipê-amarelo.
Soybean seed production with high physiological quality is important for ensuring populations of recommended plants for each cultivar. It is also known that there is genetic variability for this characteristic among the soybean cultivars. The objective was to study the genes expressionof protein and gene transcript involved in the physiological quality of soybean seeds. The seeds of CD 206 and CD 201 cultivars were classified as high quality while Savana and Emgopa 316 cultivars were classified as low quality by germination and vigor tests. Physiological, enzymatic and transcripts analysis were held in seeds of each cultivar during two harvest seasons, R8 and R8 + 15 days; at protein level the alcohol dehydrogenase isoenzyme systems (ADH), phosphoglucoisomerase (PGI), superoxide dismutase (SOD), catalase (CAT), malate dehydrogenase (MDH) and isocitrate lyase (ICL). The PCR technique in real time (qRT-PCR) was used for transcritome studies for quantitative gene expression analysis. The method used was the comparative Ct considering the relative expression levels in relation to cultivar of high quality CD 201. It is concluded that there is higher enzymes expression involved in respiration, alcohol dehydrogenase (ADH), malate dehydrogenase (MDH) and phosphoglucoisomerase (PGI), in seeds with high physiological quality, especially when harvesting is delayed. The proteomic and transcriptomic profiles related to the genes involved in free radicals removing systems in soybeans varies among cultivars and the season of seed harvest.
The objective of this study was to evaluate the enzymes expression during the seeds germination process of ever-lasting species Comanthera elegans and Comanthera bisulcata. For the evaluation of the seeds physiological potential, the germination test and index of germination speed were performed. The expression of enzymes esterase (EST), malate dehydrogenase (MDH), alcohol dehydrogenase (ADH), superoxide dismutase (SOD), catalase (CAT) and endo-β-mannanase during the germination process were evaluated. The expression of these enzymes was evaluated in dried seeds, in the protrusion, in the emergence of the primal leaf, at the beginning of the formation of normal seedling and dormant seeds at the end of the germination process. To the extent that the germination process occurs in the species C. bisulcata and C. elegans there is greater expression of the enzyme CAT and lower of the enzyme EST. There is variation in the expression of the enzymes SOD, ADH and MDH in seeds of both species during the germination process. The enzyme endo-β-mannanase presents greater activity in seeds with radicle protrusion in the two studied species.
The purpose of this paper is to investigate three anomalies in the São Paulo Stock Exchange (BOVESPA) index: the day-of-the-week effect, the twist on the Monday effect and the holiday effect. The period from Jan/1995 to Dec/2007 is analyzed, with subperiods established according to presidential terms. The paper addresses the theories on market efficiency and on the seasonal effects analyzed. Statistics indicate that the anomalies were not consistently present during the periods studied.
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