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de Brito G.G.,Laboratorio Of Biotecnologia Vegetal | Caixeta E.T.,Federal University of Vicosa | Gallina A.P.,Federal University of Vicosa | Zambolim E.M.,Federal University of Vicosa | And 3 more authors.
Euphytica | Year: 2010

The most important disease of Coffea arabica is coffee leaf rust caused by the fungus Hemileia vastatrix. The purpose of this study was to characterize the inheritance of coffee resistance gene(s) to race II of this pathogen and to identify and map molecular markers linked to this trait. Different populations were used: F2 (160 plants), BCr (20), and BCs (135), derived from a cross between the resistant genotype Híbrido de Timor UFV 427-15 and the susceptible cultivar Catuaí Amarelo UFV 2143-236 (IAC 30). The segregation analysis showed that the resistance of Híbrido de Timor to race II of the H. vastatrix is conferred by a single dominant gene. The amplification of 176 AFLP (Amplified fragment length polymorphism) primer combinations using bulked segregant analysis (BSA) allowed the identification of three molecular markers linked to the resistance gene. Genetic mapping of these three markers in the F2 population indicated that they are distributed on both sides, flanking the resistance gene. The markers E.CTC/M.TTT405 and E.CGT/M.TGT300 were found linked to the resistance gene at 8.69 cM (LOD 18.91) and 25.10 cM (LOD 5.37), respectively, while E.CCT/M. TTC230 was localized on the other side of the gene, at 20.50 cM (LOD 6.15). These markers are the first rust resistance markers identified in Híbrido de Timor and can be useful for marker assisted selection in coffee breeding programs. © 2010 Springer Science+Business Media B.V. Source

Saldamando C.I.,National University of Colombia | Saldamando C.I.,Laboratorio Of Biotecnologia Vegetal | Marquez E.J.,National University of Colombia
Revista de Biologia Tropical | Year: 2012

The genus Spodoptera includes 30 species of moths considered important pests worldwide, with a great representation in the Western Hemisphere. In general, Noctuidae species have morphological similarities that have caused some difficulties for assertive species identification by conventional methods. The purpose of this work was to generate an approach to the genus phylogeny from several species of the genus Spodoptera and the species Bombyx mori as an out group, with the use of molecular tools. For this, a total of 102 S. frugiperda larvae were obtained at random in corn, cotton, rice, grass and sorghum, during late 2006 and early 2009, from Colombia. We took ADN samples from the larval posterior part and we analyzed a fragment of 451 base pairs of the mitochondrial gene cytochrome oxydase I (COI), to produce a maximum likelihood (ML) tree by using 62 sequences (29 Colombian haplotypes were used). Our results showed a great genetic differentiation (K2 distances) amongst S. frugiperda haplotypes from Colombia and the United States, condition supported by the estimators obtained for haplotype diversity and polymorphism. The obtained ML tree clustered most of the species with bootstrapping values from 73-99% in the interior branches; with low values also observed in some of the branches. In addition, this tree clustered two species of the Eastern hemisphere (S. littoralis and S. litura) and eight species of the Western hemisphere (S. androgea, S. dolichos, S. eridania, S. exigua, S. frugiperda, S. latifascia, S. ornithogalli and S. pulchella). In Colombia, S. frugiperda, S. ornithogalli and S. albula represent a group of species referred as "the Spodoptera complex" of cotton crops, and our work demonstrated that sequencing a fragment of the COI gene, allows researchers to differentiate the first two species, and thus it can be used as an alternative method to taxonomic keys based on morphology. Finally, the ML tree did not cluster S. frugiperda with S. ornithogalli, suggesting that both species do not share the same recent ancestral even though they coexist in cotton. We suggest sequencing other genes (mitochondrial and nuclear) to increase our understanding of this genus evolution. Source

de Souza R.A.V.,Federal University of Mato Grosso | Braga F.T.,Laboratorio Of Biotecnologia Vegetal | Neto J.V.,Empresa de Pesquisa Agropecuaria e Extensao Rural de Santa Catarina | de Mendonca E.A.F.,Federal University of Mato Grosso | And 2 more authors.
Pesquisa Agropecuaria Brasileira | Year: 2011

The objective of this work was to evaluate the effect of different storage conditions on the preservation of the viability and germination of olive zygotic embryos. A completely randomized block design was used, in a 4x2 factorial arrangement. Fruits of the cultivar Santa Catalina were subjected to different storage conditions - plastic bag in refrigerator at 4-5°C and 15% relative humidity (RH), dissector in refrigerator at 4-5°C and 12% RH, plastic bag at laboratory room at 27±1°C and 55% RH, dissector in laboratory room at 27±1°C and 30% RH -, and to storage periods of 30 and 120 days. In vitro germination and viability were evaluated by the tetrazolium test at 30 and 120 days of storage. The highest germination rate (91.66%) and viability (33.33%) were observed at 4-5°C and 12% RH at 30 days. This storage condition preserves olive fruits for longer time. Source

Ribeiro J.M.,Embrapa Semiarido | de Melo N.F.,Embrapa Semiarido | dos Santos Coelho A.K.N.,Laboratorio Of Biotecnologia Vegetal | dos Santos Teixeira Pinto M.,Laboratorio Of Biotecnologia Vegetal
Revista Ceres | Year: 2012

Despite offering a number of advantages as the quality of final product, the technique of in vitro cultivation of plants is still considered expensive due to, among other things, the use of reagents with high purity for the preparation of nutrient media. Among the alternatives that can be adopted to reduce the costs associated with the production of seedlings, the replacement of the PA product for those with lower has potential. Based on this information, the purpose of this study was to evaluate the effect of molasses of sugar cane on in vitro development of banana cv. Maçã. For this purpose, banana plants were inoculated in nutrient media made on the basis of sugarcane molasses, with four different concentrations (Brix of 1.5, 3.0, 4.5 and 6.0) and data were compared with those of plants grown on MS medium (control), in a total of five treatments. Despite plants have been developed in all treatments, it was observed that for the variables leaf number and fresh biomass, plants cultivated in MS medium (control) had higher performances. However, for the average number of roots, there was no statistical difference between treatments. The sugarcane molasses did not favor the development of banana plants, but can be used for in vitro rooting of these plants. Source

De Lima R.B.,Federal University of Parana | Dos Santos T.B.,Laboratorio Of Biotecnologia Vegetal | Vieira L.G.E.,Laboratorio Of Biotecnologia Vegetal | De Lourdes Lucio Ferrarese M.,State University of Maringa | And 4 more authors.
Carbohydrate Polymers | Year: 2014

Coffea arabica is the most important agricultural commodity in the world, and salinity is a major threat to its sustainable irrigation. Coffee leaf polysaccharides from plants subjected to salt stress were extracted and the leaves visualized through optical and electron microscopy. Alterations were detected in the monosaccharide composition of the pectin and hemicelluloses, with increases in uronic acid in all fractions. Changes in the polysaccharides were confirmed by HPSEC and FTIR. Moreover, the monolignol content was increased in the final residue, which suggests increased lignin content. The cytoplasm was altered, and the chloroplasts appeared irregular in shape. The arrangement of the stroma lamellae was disordered, and no starch granules were present. It was concluded that leaves of C. arabica under salt stress showed alterations in cell wall polysaccharides, increased monolignol content and structural damage to the cells of the mesophyll. © 2014 Published by Elsevier Ltd. Source

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