BR 020

Planaltina, Brazil
Planaltina, Brazil
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Fronza E.,Grande Rio University | Fronza E.,University of Caxias do Sul | Specht A.,BR 020 | Corseuil E.,Rua Cecimbra Jaques
Check List | Year: 2011

The result of an inventory on the lepidopteran fauna associated with the South American Holly (erva-mate) is described. This inventory was based on a bibliographic review, the examination of specimens deposited in scientific collections from the state of Rio Grande do Sul, the systematic collection within commercial erva-mate farms located in Anta Gorda, RS, and on the occasional collections from native trees within the Região dos Vinhedos campus of the Universidade de Caxias do Sul. Every fifteen days between 20 August 2005 and 19 August 2006, 150 trees were visually inspected and all Lepidoptera were collected. A list of 75 lepidopteran taxa belonging to 16 families is presented, including 27 new occurrences for the erva-mate crop, of which 14 species represent new records for the state. © 2011 Check List and Authors.

This work had the objective of testing cleft grafting as a way to asexually propagate different genotypes of Surinam cherry. Bud woods of around 5 cm length were collected from seven genotypes of the Germplasm Bank of Embrapa Clima Temperado, Pelotas, RS. Seedling plants of Surinam cherry seedlings were used as rootstocks. The average diameter at the grafting point was 2.5 mm. Grafting was done on September, 2006. The experiment was carried out as a completely randomized design with four replications and 10 plants per plot. Evaluations were based on percentages of sprouting and budding efficiency. Percentages of sprouting were between 45.0% and 95% whereas percentages of grafting success in obtain the desirable clones were among 40.0% to 87.5%. Percentages above 65.0% for evaluated parameters, sprouting and grafting success were obtained in selections "Pit 75", "Pit 61" and "Pit 137". There were differences among genotypes for percentage of cleft grafting success in Surinam cherry propagation. This type of grafting is recommended for Surinam cherry vegetative propagation.

AFLP molecular markers were used aiming to study the genetic variability within and between Surinam cherry (Eugenia uniflora) populations, originated from self-pollination and open pollination of two selections (Pit 15 and Pit 52) of the Embrapa Clima Temperado collection. The objective was to achieve a better understanding about the reproduction way of this species. Two progenies were obtained from each selection being one from self-pollination and another from open-pollination, resulting in four populations. The analysis was carried out in 18 individuals of each progeny and the two mother plants, totalizing 74 genotypes. Three AFLP primer combinations were used and the genetic similarity was calculated by Jaccard coefficient. Genetic variability within and between populations was estimated by AMOVA. The three primer combinations amplified 178 loci, of which 114 (64%) were polymorphic, considering all the genotypes. There was not a clear separation between the two progenies of the same mother plant. Larger polymorphism of AFLP markers was observed in the open-pollinated populations. The proportion of total genetic variability was significant, between populations from open-pollination, although smaller than the variability observed within populations. The Surinam cherry reproduction is based on both self-fertilization as well as cross-pollination. Nevertheless it is rather important to do further studies in order to determine which reproduction mode is the most efficient.

Deuner C.,Federal University of Pelotas | Maia M.S.,Federal University of Bahia | Deuner S.,BR 020 | Almeida A.S.,Federal University of Pelotas | Meneghello G.E.,Federal University of Bahia
Revista Brasileira de Sementes | Year: 2011

This study aimed to evaluate the effect of different salt concentrations on the germination, initial biomass and oxidative stress of four cowpea genotypes, commonly grown in the São José do Norte region, RS. The seeds of the genotypes Amendoim, Mosqueado, Baio and Preto were planted in rolls of "germitest" paper, soaked in a solution of sodium chloride at concentrations of zero, 50, 100, 150 and 200 mM and placed to germinate at a constant temperature of 25 °C. Variables studied were: germination, first count, length and dry mass of the shoots and roots of seedlings, lipid peroxidation and the specific activity of superoxide dismutase, ascorbate peroxidase and catalase. Increasing salt concentration adversely affected seed germination and also the first count of the four cowpea genotypes for the 100 mM salt treatment. Joint analysis of the regression curves for the growth parameters showed the same tendency for the four genotypes, with a significant growth reduction as salt stress increased. Stress effects were also evident from increased lipid peroxidation in the200 mM salt treatment, followed by reduced enzyme antioxidant activity, since in the intermediate salt concentrations, the antioxidant enzymes efficiently eliminated reactive oxygen species (ROS), preventing oxidative stress. These results indicate that, at intermediate doses of salt, there was good initial development of the four cowpea genotypes and the best response was observed in the Amendoim genotype.

Carneiro M.M.L.C.,Federal University of Lavras | Deuner S.,BR 020 | de Oliveira P.V.,Federal University of Pelotas | Teixeira S.B.,Federal University of Pelotas | And 3 more authors.
Revista Brasileira de Sementes | Year: 2011

This study aimed to evaluate the effect of agents inducing water and saline stress on the seed germination and early growth and antioxidant activity in sunflower seedlings. Sunflower seeds, cv. M735, were germinated on moistened paper in solutions with osmotic potentials of 0.0, -0.2, -0.4 and -0.8 MPa induced by PEG 6000 and NaCl. The germination test was conducted with four samples of 100 seeds and four replicates per treatment, in a germination chamber at 25 oC without light. We evaluated the final percentage and speed of germination index, and the initial growth and activity of antioxidant enzymes in sunflower seedlings. Water stress induced by PEG 6000 increased the percentage of seeds germinated in the potential of -0.2 MPa, on the other hand, for NaCl in the potential of -0.8 MPa, there was a significant reduction. For this same potential, there was also a reduction in the rate of seed germination speed index in both conditioning agents. For the parameters of growth, shoot length decreased linearly with increasing concentrations of PEG 6000 and NaCl. As for the dry mass of leaves and roots and root length, this effect was more significant only in the potential of -0.8 MPa. The enzymes SOD, APX and CAT activity tended to be lower in seedlings originating from seeds in PEG 6000. In the presence of NaCl, the activity of SOD in the leaves increased significantly in the three tested for potential witnesses. For APX and CAT increase was observed at potentials of -0.2 and -0.4 MPa. In the roots there was no significant difference. An analysis of the evaluated parameters indicates that sunflower cv M735, under the conditions tested, showed tolerance to drought stress and salt until the potential of -0.4 MPa.

de Lima C.A.,University of Brasilia | Faleiro F.G.,BR 020 | Junqueira N.T.V.,BR 020 | Cohen K.O.,Parque Estacao Biologica PqEB. Av.W | Guimaraes T.G.,BR 020
Revista Brasileira de Fruticultura | Year: 2013

Although the high commercial potential of pitaya, there are yet few studies of physico-chemical characterization of pitaya fruits, especially considering wild species from the Brazilian Savannas. This study was conducted with the objective to analyze the physico-chemical characterization, total polyphenols and yellow flavonoids of fruits of Hylocereus costaricensis, Hylocereus undatus, Selenicereus setaceus and Selenicereus megalanthus pitaya species. For the physico-chemical analyzes the percentage of soluble solids, pH value and total acidity. For the phenolic compounds quantification, total flavonoids and yellow polyphenols extractable were analyzed. Significant differences of chemical characteristics and the amount concentration of phenolic compounds were observed among pitaya species and basal, middle and apical portions of fruit. The species S. megalanthus had higher amounts of soluble solids. This characteristic is more pronounced in the middle part of the fruit of all species. There was significant difference of pH, with values ranging from 4.84 to 5.67. The pitaya fruits are classified as low acid fruits. The acid content ranged from 0.10% to 0.15% of citric acid. H. costaricensis presented higher amount of total polyphenols and yellow flavonoids, differing significantly from the other species.

Filho J.S.,University of Brasilia | Marchao R.L.,BR 020 | de Carvalho A.M.,BR 020 | Carmona R.,University of Brasilia
Revista Ciencia Agronomica | Year: 2014

The aim of this study was to assess the influence of short-season sorghum-grass intercropped systems on weed population dynamics. The integrated systems consisted of sorghum grown at two row spacings (0.50 m and 0.70 m), intercropped with palisade grass or Congo grass. We also used sole crops of sorghum, palisade grass, Congo grass and a fallow to serve as a reference for spontaneous vegetation. The experiment was conducted in 2010 and 2011 at Planaltina (Federal District) in Brazil. Weed populations and weed dry matter were assessed during the short season and during the succession soybean cycle. The weed soil seed bank was sampled in both years of the study. Sorghum at a row spacing of 0.50 m intercropped with Congo grass reduced the Ageratum conyzoides population. The Tridax procumbens seed bank in the soil was reduced by using sorghum at a the row spacing of 0.70 m, whether intercropped or not. Planting palisade grass during the short season reduced Digitaria sanguinalis in the soil seed bank. Planting palisade grass or Congo grass as a sole crop or intercropped reduced the number of weed seeds in the soil, showing that these species can be recommended for integrated weed management in intercropped systems.

Pires M.V.V.,University of Brasilia | Faleiro F.G.,BR 020 | Silva J.C.S.,BR 020 | De Melo J.T.,BR 020 | Peixoto J.R.,University of Brasilia
Revista Brasileira de Fruticultura | Year: 2015

This study aimed to evaluate the genetic variability of the araticum collections from Embrapa Cerrados and others regions near to the Federal District, using RAPD and microsatellites markers as well as morphological analysis. Young leaves of 18 araticum accessions were collected and used for genomic DNA extraction. Genomic DNA samples from each accession were amplified for obtaining RAPD and microsatellites markers. Morphological analysis were performed using 23 characteristics of each araticum accession. Genetic dissimilarities among the 18 araticum accessions showed high genetic variability among them and cluster analysis led to the formation of three similarity groups. It was observed low genetic dissimilarities among accessions from Embrapa Cerrados and high genetic dissimilarities among accessions from others regions. These accessions are important as genetic variability sources to enlarge the current Embrapa Cerrados collection and for future studies of morphological and agronomic germplasm characterization. © 2015, Sociedade Brasileira de Fruticultura. All rights reserved.

Junqueira K.P.,Embrapa Transferencia de Tecnologia | Faleiro F.G.,BR 020 | Junqueira N.T.V.,BR 020 | Bellon G.,BR 020 | And 2 more authors.
Revista Brasileira de Fruticultura | Year: 2010

Brazilian savanna pitayas naturally vegetate on solid rocky sandstone or quartzite, tree trunks and on rocky fields sand soils at Minas Gerais, Goiás, Distrito Federal, Tocantins, Rio de Janeiro and Bahia, with strong evidences that Brazil central region is the biggest pitayas dispersion center, because of the wide phenotypic diversity observed in collected accesses. The objective was to realize genetic diversity study of 13 pitaya accesses maintained at Embrapa Cerrados germoplasm collection through RAPD (Random Amplified Polymorphic DNA) molecular markers. Each access genomic DNA were extracted and fourteen decamer initiators were used to obtain RAPD molecular markers, that were converted in a binary data matrix, from where we estimate genetic distances between accesses and realize grouping and graphic dispersion analysis. 162 RAPD markers were obtained, making 11,57 markers medium per primer. From all the markers, 154 (95,06%) were polymorphic. Genetic distances varied within 0,088 and 0,848, the biggest values observed refer to distance between Unaí, MG access and Seleção Embrapa Cerrados access. The most different access was "Unaí, MG", that showed 0,675 of genetic distance average in relation to others accessions. The high genetic distance verified is due to the fact that the referred accesses do not belong to the same species. Pitaya accesses groups had little relation to their geographic origin. The genetic diversity found at the Brazilian savannas allows including this biome at pitaya species diversity center, showing good perspectives to studies about this fruit potential.

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