Ângela Diniz Campos

Atividade de peroxidase e polifenoloxidase na resistência do feijão à antracnose

The objective of this work was to evaluate the influence of peroxidase and polyphenol oxidase enzymes in anthracnose resistance of four bean cultivars. Seedlings were sprinkled with salicylic acid and delta race of Colletotrichum lindemuthianum (inducer fungus) and after three days they were inoculated with 33/95 virulent pathotype of C. lindemuthianum. Enzyme activity and phenol levels were evaluated three days after inducer fungus application and five days after inoculation with virulent pathotype. Plants treated with salicylic acid and inducer fungus presented higher activity increases of both enzymes, in all cultivars. Higher impulses in enzymatic activity were observed in cultivars with higher disease resistance. One isoperoxidase appeared in treatments with inducer fungus, salicylic acid, after inoculation with virulent pathotype, and in control plants, in AB 136, Rio Tibagi and Macanudo cultivars. Positive correlation was observed among peroxidase and polyphenol oxidase activity, phenolic compound levels and anthracnose resistance.

Induction of chalcone synthase and phenylalanine ammonia-lyase by salicylic acid and Colletotrichum lindemuthianum in common bean

The activities of the enzymes chalcone synthase (CHS) and phenylalanine ammonia-lyase (PAL) were measured in leaf extracts obtained from four cultivars of the common bean (AB 136, Rio Tibagi, Carioca and Macanudo). Two stages of plant development were examined: plantlets (V2) and the onset of blooming (R6). Initially, the plants were either treated with salicylic acid or inoculated with the delta race of Colletotrichum lindemuthianum (inductive fungus) and after three days they were evaluated for enzyme activity. Afterwards, all plants were inoculated (challenged) with the virulent pathotype 33/95 of C. lindemuthianum except for the water control. Five days later, the activities of PAL and CHS were evaluated. There were significant changes in the activities of both enzymes three days after treatment with salicylic acid or inductive fungus when compared to the control. Five days after inoculation with with the virulent pathotype 33/95 of C. lindemuthianum CHS activity in the Macanudo was similar to control plants that were not treated with salicylic acid or the inductive fungus but inoculated with 33/95 C. lindemuthianum. The increase in enzyme activity after challenge with 33/95 C. lindemuthianum was greatest for the salicylic acid treatment in the cultivar AB 136, followed by Rio Tibagi and Carioca.

Indução de resistência sistêmica à antracnose em feijoeiro-comum pela raça delta avirulenta de Colletotrichum lindemuthianum

The objectives of this work were to evaluate the potential of the avirulent delta race of Colletotrichum lindemuthianum as a protector against virulent races of this fungus and induce systemic resistance to anthracnose in common bean (Phaseolus vulgaris). Four common bean cultivars were evaluated for changes in the activities of beta-1,3-glucanase and chitinase at two common bean developmental stages, V2 and R6, three days after the infection with delta race of C. lindemuthianum, in comparison with control applications of water and salicylic acid. The plants were then infected with a spore suspension of 33/95, a virulent C. lindemuthianum patotype and reevaluated five days later for the enzyme activities. Significant increases in the activities of both beta-1,3-glucanase and chitinase were observed after inoculation of inductive fungus at the two evaluation periods, at both plant development stages. The activities of both beta-1,3-glucanase and chitinase varied among cultivars and among plant development stages. A significant correlation was observed between the disease severity and the enzyme activity. The avirulent delta race of C. lindemuthianum reduced the severity of anthracnose on common bean and may have the potential to control the disease.

Determinação por cromatografia gasosa de açúcares em frutíferas de clima temperado

The temperate-zone deciduous fruit trees present the phenomenon of dormancy. In that period, there is the conversion of the starch in soluble sugars, as substratum for the resumption of growth in the spring. Seeking to better understanding the physiology of the plants in answers to events as the climatic variations, stresses and adaptation problems, this study was done in the Laboratory of Crop Physiology of Embrapa Temperate Climate, with the objective of describing a methodology for determination of concentrations of the soluble sugars (fructose, sorbitol, a-glucose, b-glucose and sucrose), in tissues of fruit tree, through gaseous chromatography. The chromatograph used for the analyses of the sugars was the GAS CHROMATOGRAPH with the column of the type Packed Column J. K. of 3,2mm of diameter for 2m of length packed with Silicon IF-52 Uniport HP 80/100 mesh. Through the gaseous chromatography it is obtained efficiency and chromatographic resolution to soluble sugars determination, being this way, advantageous to use this methodology.

Teores de carboidratos em estacas lenhosas de mirtileiro

O objetivo do trabalho foi avaliar as alteracoes no teor de carboidratos em estacas lenhosas de mirtileiro das cultivares Delite, Powder Blue e Selecao 19. Foram analisados os teores de amido e de acucares soluveis a partir de ramos coletados em quatro epocas diferentes (03/06, 04/07, 24/07 e 11/08/2008) em um primeiro experimento e, posteriormente, avaliou-se o teor de carboidratos em estacas, coletadas nas mesmas epocas citadas, submetidas a condicoes de enraizamento. Verificou-se que a cv. Powder Blue possui maior reserva amilacea que a cv. Delite e Selecao 19. Estacas lenhosas de mirtileiro com baixos teores de amido, quando submetidas ao enraizamento, apresentam ressintese de amido. No fim do periodo de inverno, ocorre um aumento na concentracao de amido nos ramos lenhosos de mirtileiro. Maior teor de amido nos ramos durante o periodo de inverno esta associado a maior taxa de enraizamento.

Systematic review and technological overview of the antimicrobial activity of Tagetes minuta and future perspectives

ETHNOPHARMACOLOGICAL RELEVANCE The antimicrobial potential of Tagetes minuta was correlated with its traditional use as antibacterial, insecticidal, biocide, disinfectant, anthelminthic, antifungal, and antiseptic agent as well as its use in urinary tract infections. AIM OF THE STUDY This study aimed to systematically review articles and patents regarding the antimicrobial activity of T. minuta and give rise to perspectives on this plant as a potential antimicrobial agent. MATERIALS AND METHODS A literature search of studies published between 1997 and 2015 was conducted over five databases: MedLine (PubMed), Web of Science, Scopus, Google Scholar, Portal de Periódicos Capes and SciFinder, grey literature was explored using the System for Information on Dissertations database, and theses were searched using the ProQuest Dissertations and Theses Full text database and the Periódicos Capes Theses database. Additionally, the following databases for patents were analysed: United States Patent and Trademark Office (USPTO), Google Patents, National Institute of Industrial Property (INPI) and Espacenet patent search (EPO). The data were tabulated and analysed using Microsoft Office Excel 2010. RESULTS After title screening, 51 studies remained and this number decreased to 26 after careful examinations of the abstracts. The full texts of these 26 studies were assessed to check if they were eligible. Among them, 3 were excluded for not having full text access, and 11 were excluded because they did not fit the inclusion criteria, which left 10 articles for this systematic review. The same process was conducted for the patent search, resulting in 4 patents being included in this study. CONCLUSION Recent advances highlighted by this review may shed light on future directions of studies concerning T. minuta as a novel antimicrobial agent, which should be repeatedly proven in future animal and clinical studies. Although more evidence on its specificity and clinical efficacy are necessary to support its clinical use, T. minuta is expected to be a highly effective, safe and affordable treatment for infectious diseases.

Genotypic differences in cyanogenic glycosides levels of compatible Prunus persica P. persica and incompatible P. persica P. mume combinations

We acknowledge the Coordination for the Improvement of Higher Education Personnel (CAPES) for their financial support.

Modo de ação de fosfitos de potássio no controle da podridão olho de boi em maçã

The bulls eye rot, caused by Cryptosporiopsis perennans, is the most important postharvest disease of apples in Brazil. The aims of this study were to evaluate a) the use of potassium phosphite salts isolated or in mixture with the fungicide captan for disease control in the field and in vitro; b) the physical/chemical alterations of fruits and, c) the effect of these salts on peroxidase and phenylalanine ammonia-lyase activity in artificially inoculated apples. Potassium phosphites and captan were applied in the 2007/08 season, at Vacaria City, to an orchard of cv. Pink Lady(r), starting at 45 days or 24h prior to harvest. The activity of peroxidase and phenylalanine ammonia-lyase was measured for apple fruits at 24h and 14 days after inoculations with the pathogen. Applications of potassium phosphite + captan reduced by 60% the postharvest loss caused by bulls eye rot, besides decreasing 66% of the inocula produced on apple surface when applied on the day prior to harvest. Potassium phosphite inhibited the in vitrogrowth of the fungus without affecting peroxidase and phenylalanine ammonia-lyase activity. Potassium phosphites showed eradicating fungicide action and potential to be used in the integrated management of bulls eye rot.

Genetic variance of reducing sugars and dry matter and their correlations with agronomic traits in potatoes.

The objective of this research was to estimate the components of the variance and heritability relating to reducing sugars content and to dry matter, and their correlations with some agronomic traits of potato (Solanum tuberosum L.). Forty potato clones randomly chosen by the EmbrapaCentro de Pesquisa Agropecuaria de Clima Temperado Breeding Program were used. The field experiments were carried out in the fall and in the spring of 1996, in Pelotas, RS, Brazil. Sugar and dry matter content were analyzed after storing tubers in cold chamber (5±1oC). Genetic variances relating to reducing sugars and to dry matter content were moderate, and error variances were high, providing relatively low heritability values for both traits. The reducing sugar content was positively and significantly correlated with most of the agronomic traits and negatively correlated with dry matter content. The correlations between dry matter and agronomic traits were low and not significant.

Variance of genetic reducing sugars and dry matter and their correlations with agronomic traits in potatoes

The objective of this research was to estimate the components of the variance and heritability relating to reducing sugars content and to dry matter, and their correlations with some agronomic traits of potato (Solanum tuberosum L.). Forty potato clones randomly chosen by the EmbrapaCentro de Pesquisa Agropecuaria de Clima Temperado Breeding Program were used. The field experiments were carried out in the fall and in the spring of 1996, in Pelotas, RS, Brazil. Sugar and dry matter content were analyzed after storing tubers in cold chamber (5±1oC). Genetic variances relating to reducing sugars and to dry matter content were moderate, and error variances were high, providing relatively low heritability values for both traits. The reducing sugar content was positively and significantly correlated with most of the agronomic traits and negatively correlated with dry matter content. The correlations between dry matter and agronomic traits were low and not significant.