Passo Fundo, Brazil
Passo Fundo, Brazil

Time filter

Source Type

Zhou G.,University of Tasmania | Zhou G.,CSIRO | Pereira J.F.,Embrapa Wheat | Delhaize E.,CSIRO | And 3 more authors.
Journal of Experimental Botany | Year: 2014

Malate and citrate efflux from root apices is a mechanism of Al 3+ tolerance in many plant species. Citrate efflux is facilitated by members of the MATE (multidrug and toxic compound exudation) family localized to the plasma membrane of root cells. Barley (Hordeum vulgare) is among the most Al3+-sensitive cereal species but the small genotypic variation in tolerance that is present is correlated with citrate efflux via a MATE transporter named HvAACT1. This study used a biotechnological approach to increase the Al3+ tolerance of barley by transforming it with two MATE genes that encode citrate transporters: SbMATE is the major Al 3+-tolerance gene from sorghum whereas FRD3 is involved with Fe nutrition in Arabidopsis. Independent transgenic and null T3 lines were generated for both transgenes. Lines expressing SbMATE showed Al 3+-activated citrate efflux from root apices and greater tolerance to Al3+ toxicity than nulls in hydroponic and short-term soil trials. Transgenic lines expressing FRD3 exhibited similar phenotypes except citrate release from roots occurred constitutively. The Al3+ tolerance of these lines was compared with previously generated transgenic barley lines overexpressing the endogenous HvAACT1 gene and the TaALMT1 gene from wheat. Barley lines expressing TaALMT1 showed significantly greater Al3+ tolerance than all lines expressing MATE genes. This study highlights the relative efficacy of different organic anion transport proteins for increasing the Al3+ tolerance of an important crop species. © 2014 The Author.


Alves A.A.,Embrapa Agroenergy | Alves A.A.,Federal University of Viçosa | Rosado C.C.G.,Federal University of Viçosa | Faria D.A.,Embrapa Genetic Resources and Biotechnology | And 6 more authors.
Euphytica | Year: 2012

Eucalypts are susceptible to a wide range of diseases. One of the most important diseases that affect Eucalyptus plantations worldwide is caused by the rust fungus Puccinia psidii. Here, we provide evidence on the complex genetic control of rust resistance in Eucalyptus inter-specific hybrids, by analyzing a number of full-sib families that display different patterns of segregation for rust resistance. These families are totally unrelated to those previously used in other inheritance studies of rust resistance. By using a full genome scan with 114 genetic markers (microsatellites and expressed sequence tag derived microsatellites) we also corroborated the existence and segregation of a resistance locus, explaining 11.5% of the phenotypic variation, on linkage group 3, corresponding to Ppr1. This find represents an additional validation of this locus in totally unrelated pedigree. We have also detected significant additive × additive digenic interactions with LOD >10.0 on several linkage groups. The additive and epistatic QTLs identified explain between 29.8 and 44.8% of the phenotypic variability for rust resistance. The recognition that both additive and non-additive genetic variation (epistasis) are important contributors to rust resistance in eucalypts reveals the complexity of this host-pathogen interaction and helps explain the success that breeding has achieved by selecting rust-resistant clones, where all the additive and non-additive effects are readily captured. The positioning of epistatic QTLs also provides starting points to look for the underlying genes or genomic regions controlling this phenotype on the upcoming E. grandis genome sequence. © 2011 Springer Science+Business Media B.V.


Galao O.F.,State University Londrina | Teixeira A.I.,Federal University of Viçosa | Moreira M.A.,Federal University of Viçosa | Carrao-Panizzi M.C.,Embrapa Wheat | Visentainer J.V.,State University of Maringá
Semina:Ciencias Agrarias | Year: 2013

The objective of this study was to evaluate the effects of genetic and environmental variation on levels of beta-conglycinin and glycinin in commercial soybean cultivars, which were sown in showcases at Embrapa Soja, Londrina, simultaneously in Ponta Grossa, south Brazil. The concentration of protein fractions was determined by densitometry after electrophoresis in 20 cultivars, 14 conventional and 6 transgenic . We observed a significant variation as the ratio of beta-conglycinin (7S) and glycinin (11S) between the cultivars analyzed. Most 11S/7S ratios (2.21) was observed in the BRS 184, Ponta Grossa and lowest (1.31) in the BRS 233, Londrina. On average, transgenic varieties of Ponta Grossa were higher than in Londrina for both, taking into account the amount of protein fractions.


Barbedo J.G.A.,Embrapa Agricultural Informatics | Tibola C.S.,Embrapa Wheat | Fernandes J.M.C.,Embrapa Wheat
Biosystems Engineering | Year: 2015

Because of the health risks associated with the ingestion of the mycotoxin deoxynivalenol (DON) produced by Fusarium head blight (FHB), improving its detection in wheat kernels is a major research goal. Currently, assessments are largely performed visually by human experts. Being subjective, such assessments may not always be consistent or entirely reliable. As a result, methods with a higher degree of objectivity have been investigated, and special attention has been dedicated to the use of hyperspectral imaging (HSI) as the basis for more reliable detection strategies. This paper presents an algorithm for automatic detection of FHB in wheat kernels using HSI. The goal was to develop a simple and accurate algorithm which gave as output an index that can be interpreted as the likelihood of the kernel being infected by FHB. With a classification accuracy above 91%, the developed algorithm was robust to factors such as shape, orientation, shadowing and clustering of kernels. It was shown that the algorithm was not only suitable for detecting FHB, but it also has the capability, albeit limited, of estimating DON concentrations in wheat kernels. © 2015 IAgrE.


Panizzi A.R.,Embrapa Wheat | Agostinetto A.,University Of Passo Fundo | Lucini T.,Federal University of Paraná | Pereira P.R.V.D.S.,Embrapa Wheat
Crop Protection | Year: 2016

The green belly stink bug, Dichelops furcatus (F.) (Hemiptera: Heteroptera: Pentatomidae) is a pest of corn and soybean in southern Brazil. It also occurs on wheat, but information on its damage to this crop is limited. To determine the need for sustainable IPM programs, the impact of this bug on wheat production should be determined. Studies were conducted in the screenhouse with 1, 2 and 4 bugs caged for 16 days on single plants, cv. 'BRS Parrudo'. During the vegetative period (plants ca. 25 cm tall), all infestation levels significantly reduced plant height and ear head length, but did not reduce grain yield. Feeding damage caused tissue necrosis on leaves. During the booting stage, grain yield was significantly reduced with 2 and 4 bugs per plant; ear heads were small, discolored and abnormally developed. In 2013 and 2014 field trials, plants were infested for 18 days with 2, 4 and 8 bugs per m2 at vegetative, booting, and milky grain stage. At these infestation levels, there was no significant reduction in grain yield. There was a significant decrease in the number of normal seedlings resulting from seeds exposed to 8 bugs per m2 at the milky grain stage. Results suggest that, in general, there is no need to control D. furcatus on wheat, unless numbers are ≥8 bugs per m2 during reproductive period. © 2015 Elsevier Ltd.


Vazquez D.,INIA La Estanzuela | Berger A.G.,INIA La Estanzuela | Cuniberti M.,Instituto Nacional de Tecnologia Agropecuaria | Bainotti C.,Instituto Nacional de Tecnologia Agropecuaria | And 7 more authors.
Journal of Cereal Science | Year: 2012

Wheat consumption is growing, with processors asking for wheat-based products showing better and more consistent quality. Genotype, environment and their interaction (G × E) play an important role in the final expression of quality attributes. An international research consortium was developed in order to evaluate the magnitude of genotype, environment and G × E effects on wheat quality of cultivars developed for different agro-ecological zones in Latin America. Genotypes released in Argentina, Brazil, Chile, Mexico, Paraguay and Uruguay, were cultivated in twenty different environments within the participating countries. Each environment was characterized for cultural practices, soil type and climatic conditions. Grain yield and analyses of test weight, protein, ash, gluten, Alveograph, Farinograph, Falling Number, SDS sedimentation and flour color were determined. Allelic variations of puroindolines and glutenins were determined in all the genotypes evaluated. Both puroindoline and gluten protein alleles corresponded to genotypes possessing medium to very good bread making quality. Large variability for most quality attributes evaluated was observed, with wider ranges in quality parameters across environments than among genotypes; even for parameters known to be largely determined by genotype. The importance of growing environment on grain quality was proved, suggesting that breeders' quality objectives should be adapted to the targeted environments. © 2012 Elsevier Ltd.


Nohato M.A.,Federal University of Pelotas | Benemann D.D.P.,Federal University of Pelotas | Oliveira C.,Federal University of Pelotas | Vargas L.,Embrapa Wheat | And 2 more authors.
Australian Journal of Crop Science | Year: 2016

The competition for resources such as light and nitrogen between red rice and cultivated rice can trigger responses in plants that interfere with growth and productivity as well as the expression of genes related to competition-induced stress. Due to its sensitivity, accuracy, and specificity, real-time reverse transcription PCR (RT-qPCR) is an important technique for analyzing differences in gene expression. In this study, we quantified the relative expression levels of genes involved in nitrogen assimilation (OsAMTs, OsGS2 and OsNADH-GOGAT2) and light capture (OsPIL1, OsCRY2 and OsCAB1) in cultivated and red rice in competition under different concentrations of nitrogen (0, 120 and 240 kg ha-1 of nitrogen). Interspecific competition in rice increased the expression of certain genes responsible for assimilating nitrogen (OsNADH-GOGAT2 and OsAMT3;1), and intraspecific competition in red rice also increased the expression of OsGS2. With the interspecific competition, both rice and red rice exhibited increased expression of genes responsible for capturing light, such as OsCRY2 and OsCAB1. With intraspecific competition, red rice showed increased OsPIL1 expression. Additionally, higher doses of nitrogen increased the expression of genes responsible for assimilating nitrogen and capturing light in both cultivated and wild rice species.


Nunes Maciel J.L.,Embrapa Wheat
CAB Reviews: Perspectives in Agriculture, Veterinary Science, Nutrition and Natural Resources | Year: 2011

Blast disease is one of the major constraints for food production in the world, affecting many crops of agricultural importance. Wheat blast, since it was first report in the mid-1980s, has been responsible for considerable damage on the wheat fields in several South American countries such as Brazil, Bolivia and Paraguay. Rice blast disease has often been considered as a model for studies on plant-pathogen interactions. Loss of the avirulence gene AVR-0039 and mutations on the AVR-Pita are significant examples associated with this interaction. The first example is related to the adaptation of Magnaporthe oryzae to the rice crop and the second to the breakdown in cultivar resistance. A large number of genes (about 80 so far) with complete resistance to rice blast have been described, and 13 of them have been cloned. These results, involving avirulence and resistance genes, are important for understanding the biological mechanisms of interaction between pathogen and host, in considering finding strategies to control the disease. There is great concern about the potential spread of the wheat blast pathogen to locations where this disease does not currently occur. There are some wheat-producing regions in the world where wheat blast has not been reported so far, but which have climatic conditions very similar to the regions in South America where wheat blast attacks quite frequently. This situation, in a scenario of climate change, is concerning and demands research action.


Tibola C.S.,Embrapa Wheat | Fernandes J.M.C.,Embrapa Wheat | Guarienti E.M.,Embrapa Wheat | Nicolau M.,Embrapa Wheat
Food Control | Year: 2015

Fusarium head blight (FHB) is a fungal disease that affects cereals and is capable of producing mycotoxins, creating health concerns. In southern Brazil, FHB of wheat is caused by the Fusarium graminearum species complex that produces mainly deoxynivalenol (DON) and zearalenone (ZON) mycotoxins. There is a need for research-based information on how different contamination levels affect these mycotoxins' distribution in the milling process. The objective of this study was to analyze the Fusarium mycotoxin distribution within each milled fraction, extracted from wheat lots artificially contaminated with a crescent gradient of mycotoxins. Wheat samples produced in 2013 season in Southern Brazil region were obtained from plots of breeding program. The wheat samples were artificially contaminated with residues of cleaning and pre-cleaning process, including light and shriveled grains, obtained from a Fusarium nursery screening plot. Pilot-scale milled wheat fractions were collected, comprising finished flour and bran. The Fusarium mycotoxin content was determined by chromatography (UHPLC-MS/MS). The results obtained show that DON presented exponential growth relative to the initial levels of mycotoxin in wheat milled fractions (finished flour and bran). The DON concentration was significativelly higher in bran, when compared with milled wheat and finished flour, in the DON levels lower than 1000μgkg-1. The finished flour presented lower DON levels when compared with milled wheat, but this reduction was inadequate, to meet the current regulation limits for food. © 2015 Elsevier Ltd.


Tibola C.S.,Embrapa Wheat | Fernandes J.M.C.,Embrapa Wheat | Guarienti E.M.,Embrapa Wheat
Food Control | Year: 2015

Mycotoxins are a ubiquitous contaminant and are difficult to prevent or to diminish; it is, therefore, important to establish the contributions of processing steps to eliminating mycotoxins in the production of safer foods. The objective of this study was to investigate the effects of wheat cleaning, sorting, and milling processes on Fusarium mycotoxin distribution in two naturally contaminated wheat cultivars. The study focused on evaluating the effects of first-stage processing methods, cleaning, and gravity separator, on wheat mycotoxin content. The distribution of Fusarium mycotoxins was analyzed after two milling processes. Firstly, a Laboratory Mill 3100 was used to obtain the whole milled wheat. Secondly, a pilot-scale mill Quadrumat Senior was used to get wheat milled fractions (finished flour and bran). Wheat samples (BRS Parrudo and BRS 374) were collected during the 2014 season that were highly vulnerable to Fusarium outbreaks in Southern Brazil. Fusarium toxin (DON, 3-ADON, 15-ADON, NIV, and ZON) levels were determined for all milled fractions via chromatography (UHPLC-MS/MS). The cleaning and sorting methods employed post-harvest significantly reduced the mycotoxin content in wheat. The reduction of mycotoxin was progressive through each processing method, and the gravity separator equipment resulted in the lowest contamination levels in products intended for human consumption for both cultivars. Through the milling process, the DON contamination in finished flour was significantly lower than in milled wheat; however, there were no significant differences in contamination between the milled wheat and bran. The cleaning and sorting methods for both wheat cultivars generated safer foods when compared with unsorted wheat samples (BRS Parrudo and BRS 374). © 2015 Elsevier Ltd.

Loading Embrapa Wheat collaborators
Loading Embrapa Wheat collaborators