Entity

Time filter

Source Type

Planaltina, Brazil

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. Source


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. Source


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. Source


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. Source


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. Source

Discover hidden collaborations