Sakiyama N.S.,Federal University of Viçosa |
Ramos H.C.C.,State University of Norte Fluminense |
Caixeta E.T.,Embrapa Cafe |
Pereira M.G.,State University of Norte Fluminense
Crop Breeding and Applied Biotechnology | Year: 2014
Over the past three decades, molecular marker studies reached extraordinary advances, especially for sequencing and bioinformatics techniques. Marker-assisted selection became part of the breeding program routines of important seed companies, in order to accelerate and optimize the cultivar developing processes. Private seed companies increasingly use marker-assisted selection, especially for the species of great importance to the seed market, e.g. corn, soybean, cotton, and sunflower. In the Brazilian public institutions few breeding programs use it efficiently. The possible reasons are: lack of know-how, lack of appropriate laboratories, few validated markers, high cost, and lack of urgency in obtaining cultivars. In this article we analyze the use and the constraints of marker-assisted selection in plant breeding programs of Brazilian public institutes.
de Campos M.K.F.,Instituto Agronomico do Parana |
de Carvalho K.,Instituto Agronomico do Parana |
de Souza F.S.,Instituto Agronomico do Parana |
Marur C.J.,Instituto Agronomico do Parana |
And 3 more authors.
Environmental and Experimental Botany | Year: 2011
In this study we investigated the effects of the high endogenous proline level on water relations, gas exchange and antioxidant enzymatic activity in leaves of transgenic 'Swingle' citrumelo rootstocks transformed with the P5CSF129A gene coding for the key-enzyme for proline synthesis, under water deficit. Leaf total water, osmotic and pressure potentials, stomatal conductance, photosynthetic rates and xylem sap flow were evaluated in non-transformed control and transgenic plants during water deficit treatment. Malondialdehyde (MDA) content, catalase (CAT; EC 126.96.36.199), superoxide dismutase (SOD; EC 188.8.131.52) and ascorbate peroxidase (APX; EC 184.108.40.206) activities were quantified in leaves collected based on their total water potential, representing the following conditions: irrigated (Ψw=-1.3MPa), moderate stress (Ψw=-2.3 to -2.5MPa), severe stress (Ψw=-3.8 to -3.9MPa) and recovery (24h after re-irrigation: Ψw=-1.3 to -1.9MPa). Osmotic adjustment was observed in transgenic plants until 11 days after withholding water, while pressure potential in non-transformed controls was close to zero after nine days of water deprivation. This superior maintenance of turgor pressure in leaves of transgenic plants led to higher stomatal conductance, photosynthetic and transpiration rates when compared to non-transgenic plants. Drought caused a significant decrease in APX and SOD activities in control plants, followed by an increase after re-watering. On the other hand, CAT was more active in control than in transgenic plants under irrigated condition and both stress levels. Our results suggest that transgenic plants were able to cope with water deficit better than non-transformed controls since the high endogenous proline level acted not only by mediating osmotic adjustment, but also by contributing to gas exchange parameters and ameliorating deleterious effects of drought-induced oxidative stress. © 2011 Elsevier B.V.
Carvalho K.,Instituto Agronomico do Parana |
de Campos M.K.F.,Instituto Agronomico do Parana |
Pereira L.F.P.,Embrapa Cafe |
Vieira L.G.E.,Instituto Agronomico do Parana
Analytical Biochemistry | Year: 2010
We describe the first systematic evaluation of reference genes for use in real-time quantitative polymerase chain reaction (qPCR) for water deficit stress studies in the citrus rootstock " Swingle" citrumelo. The expression levels of seven reference genes-cyclophilin (CYP), cathepsin (CtP), actin (ACT), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), elongation factor 1α (EF1α), β-tubulin (TUB), and ADP ribosylation factor (ADP)-during drought stress were tested using geNorm and NormFinder programs. Results from four experimental conditions indicated that EF1α and ADP were the most stable reference genes. Relative expression levels of Δ1-pyrroline-5-carboxylate synthetase (P5CS) was used for reference gene validation. © 2010 Elsevier Inc.
dos Santos T.B.,Instituto Agronomico do Parana IAPAR |
Budzinski I.G.F.,Instituto Agronomico do Parana IAPAR |
Marur C.J.,Instituto Agronomico do Parana IAPAR |
Petkowicz C.L.O.,Federal University of Paraná |
And 2 more authors.
Plant Physiology and Biochemistry | Year: 2011
Galactinol synthase (EC 220.127.116.11; GolS) catalyzes the first step in the synthesis of raffinose family oligosaccharides (RFOs). Their accumulation in response to abiotic stresses implies a role for RFOs in stress adaptation. In this study, the expression patterns of three isoforms of galactinol synthase (CaGolS1-2-3) from Coffea arabica were evaluated in response to water deficit, salinity and heat stress. All CaGolS isoforms were highly expressed in leaves while little to no expression were detected in flower buds, flowers, plagiotropic shoots, roots, endosperm and pericarp of mature fruits. Transcriptional analysis indicated that the genes were differentially regulated under water deficit, high salt and heat stress. CaGolS1 isoform is constitutively expressed in plants under normal growth conditions and was the most responsive during all stress treatments. CaGolS2 is unique among the three isoforms in that it was detected only under severe water deficit and salt stresses. CaGolS3 was primarily expressed under moderate and severe drought. This isoform was induced only at the third day of heat and under high salt stress. The increase in GolS transcription was not reflected into the amount of galactinol in coffee leaves, as specific glycosyltransferases most likely used galactinol to transfer galactose units to higher homologous oligosaccharides, as suggested by the increase of raffinose and stachyose during the stresses. © 2011 Elsevier Masson SAS.
Taveira J.H.S.,Federal University of Lavras |
da Rosa S.D.V.F.,Embrapa Cafe |
Borem F.M.,Federal University of Lavras |
Giomo G.S.,Instituto Agronomico |
Saath R.,Instituto Agronomico
Pesquisa Agropecuaria Brasileira | Year: 2012
The objective of this work was to evaluate the protein profiles and physiological performance of coffee seeds subjected to different drying and processing methods. We evaluated processing by dry and wet routes, the drying methods: natural, on the patio, and artificial at 60°C, or at 60°C until 30% of moisture content and 40°C until 11% (wet basis). After processing and drying, the seeds were evaluated as to their physiological performance and subjected to biochemical analyses with electrophoresis of heat-resistant LEA (late embryogenesis abundant) proteins and of the enzymes superoxide dismutase, catalase, peroxidase, esterase, polyphenol oxidase, isocitrate dehydrogenase, alcohol dehydrogenase, and malate dehydrogenase. The protein profile of coffee seeds is affected by the processing and drying methods. The coffee processed by wet route has higher tolerance to drying - shown by the higher activity of antioxidative enzymes and better physiological performance - than that processed by dry route. The activity of heat-resistant proteins and antioxidant enzymes is a promising variable for the differentiation of the quality of coffee subjected to different postharvest management.
PubMed | Embrapa Cafe, General Mills Brazil Alimentos Ltda., UDI Pesquisa & Desenvolvimento and Federal University of Lavras
Type: Journal Article | Journal: Genetics and molecular research : GMR | Year: 2015
Coffee seeds begin to develop shortly after fertilization and can take 6 to 8 months to complete their formation, a period during which all the characteristics of the mature seed are determined, directly influencing physiological quality. However, little is known about the molecular mechanisms that act during coffee seed maturation. The objective of the current study was to analyze expression of the -tubulin (TUB) and endo--mannanase (MAN) genes during different phases at the end of development and in different tissues of Coffea arabica seeds. The transcription levels of the TUB and MAN genes were quantified in a relative manner using qRT-PCR in whole seeds, and dissected into embryos and endosperms at different developmental stages. Greater expression of MAN was observed in whole seeds and in endosperms during the green stage, and in the embryo during the over-ripe stage. High TUB gene expression was observed in whole seeds during the green stage and, in the embryos, there were peaks in expression during the over-ripe stage. In endosperms, the peak of expression occurred in both the green stage and in the cherry stage. These results suggest participation of endo--mannanase during the initial seed developmental stages, and in the stages of physiological maturity in the embryo tissues. TUB gene expression varied depending on the developmental stage and section of seed analyzed, indicating the participation of -tubulin during organogenesis and coffee seed maturation.
Zanella L.,Federal University of Lavras |
Borem R.A.T.,Federal University of Lavras |
Souza C.G.,Federal University of Lavras |
Alves H.M.R.,Embrapa Cafe |
Borem F.M.,Federal University of Lavras
Natureza a Conservacao | Year: 2012
The goals of this research were to analyze the fragmentation of the Atlantic Forest and to create landscape management scenarios for the municipality of Carmo de Minas, MG, Brazil. We used landscape metrics to analyze the fragmentation process of the study area, which was historically exploited for agropastoral activities. Future scenarios were modeled to represent the potential restoration of the environment based on the behavior of the natural vegetation units. The natural vegetation in the study area is highly fragmented, and the environmental integrity of its remnants is severely threatened. The management scenarios showed how the restored natural units behave in the landscape as well as the isolation and connectivity between them. Using these models, future dynamics of the landscape can be predicted. Two important actions for the conservation of the remaining natural vegetation were identified: the maintenance of secondary forest and the restoration of permanent preservation areas. © 2012 ABECO.
Santos G.C.,Federal University of Lavras |
von Pinho E.V.R.,Federal University of Lavras |
Rosa S.D.V.F.,Embrapa Cafe
Genetics and Molecular Research | Year: 2013
Coffee (Coffea arabica L.) seeds are sensitive to desiccation and oxidative stress during drying processes. We investigated the effect of drying and moisture levels on germination-related gene expressions associated with enzymatic systems that prevent oxidative stress in coffee seeds. Coffee seeds collected at physiological maturity were subjected to slow and quick drying to 40, 30, 20, and 12% moisture levels (wet basis), and as the control, seeds without drying were used. The seeds' physiological quality was calculated as percentage of normal seedlings at 15 and 30 days, normal vigorous seedlings at 30 days, and cotyledonary leaves at 45 days. The isoenzymes esterase, catalase (CAT), peroxidase (POX), and endo-β-mannanase expressions were electrophoretically analyzed. CAT and POX expressions were analyzed using RT-qPCR with specific primers constructed from the target gene sequences from the Brazilian Coffee Genome Database. Slow drying showed better physiological quality for seeds at 40 and 12% moisture levels, while quick drying was the most effective for seeds with 20% moisture. Sensitivity to water loss was confirmed by quick drying and activation of enzymes. CAT and POX transcriptions reduced during drying. RT-qPCR revealed a complex gene-expression pattern during the oxidative process, with high gene expression in wet seeds. © FUNPEC-RP.
de Oliveira Bernardi L.F.,Federal University of Lavras |
Klompen H.,Ohio State University |
Zacarias M.S.,Embrapa Cafe |
Ferreira R.L.,Federal University of Lavras
ZooKeys | Year: 2013
Neocarus proteus sp. n., is described from caves and the surrounding epigean environment of ferruginous outcrops (Cangas) in Minas Gerais, Brazil. In addition, some notes about development in this species are presented. Neocarus proteus is the only species in the genus that has smooth or barbed genital setae and that carries coronidia on the basitarsi, tibiae and genua of legs II-III. Females carry additional setae with rounded tips on the subcapitulum, and are, on average, larger than males. This distinct sexual dimorphism appears in the tritonymphal instar and is maintained in the adults. © Leopoldo F. de O. Bernardi et al.
Dantas I.B.,Federal University of Lavras |
De Oliveira J.A.,Federal University of Lavras |
Dos Santos H.O.,Federal University of Lavras |
Von Pinho E.V.R.,Federal University of Lavras |
Da Rosa S.D.V.F.,Embrapa Cafe
Revista Brasileira de Sementes | Year: 2012
Seed quality may be affected by several factors, including permeability, color, and lignin content in the seed coat. This study aimed at evaluating influence of lignin content in the tegument of seed samples of six different soybean cultivars, in which half of each sample was inoculated with the fungus Aspergillus flavus, on the physical and physiological quality, and on the seed health, during 180 days storage period, under cold chamber with controlled conditions of temperature and RH. For that, at each interval of 60 days, samples were removed, and the physiological quality of these seeds was assessed by means of moisture and lignin contents; and by tests of seed health, germination, and electrical conductivity. The moisture content of seeds remained constant during all storage period. In the seed health test, it was found that inoculation was efficient, once the minimum incidence of the fungus in the inoculated seeds was 85%. In the germination test, there was a trend of reduction on percentage germination with the increase in storage period. However, there was an increase on electrical conductivity of seeds assessed. It was concluded that there is no interference of the lignin content in the seed coat on the resistance to infection by the fungus Aspergillus flavus, even after seed storage for a period of 180 days.