Isolation and identification of a new Bacillus glycinifermentans strain from date palm rhizosphere and its effect on barley seeds under heavy metal stress.

Soil contamination by heavy metals is one of the major problems that adversely decrease plant growth and biomass production. Inoculation with the plant growth-promoting rhizobacteria (PGPR) can attenuate the toxicity of heavy metals and enhancing the plant growth. In this study, we evaluated the potential of a novel extremotolerant strain (IS-2 T) isolated from date palm rhizosphere to improve barley seedling growth under heavy metal stress. The species-level identification was carried out using morphological and biochemical methods combined with whole genome sequencing. The bacterial strain was then used in vitro for inoculating Hordeum vulgare L. exposed to three different Cr, Zn, and Ni concentrations (0.5, 1, and 2 mM) in petri dishes and different morphological parameters were assessed. The strain was identified as Bacillus glycinifermentans species. This strain showed high tolerance to pH (6-11), salt stress (0.2-2 M), and heavy metals. Indeed, the minimum inhibitory concentrations at which bacterium was unable to grow were 4 mM for nickel, 3 mM for zinc, more than 8 mM for copper, and 40 mM for chromium, respectively. It was observed that inoculation of Hordeum vulgare L. under metal stress conditions with Bacillus glycinifermentans IS-2 T stain improved considerably the growth parameters. The capacity of the IS-2 T strain to withstand a range of abiotic stresses and improve barley seedling development under lab conditions makes it a promising candidate for use as a PGPR in zinc, nickel, copper, and chromium bioremediation.

Regulation of senescence-associated protease genes by sulphur availability according to barley (Hordeum vulgare L.) phenological stage.

BACKGROUND AND AIMS: Proteases are responsible for protein degradation during leaf senescence, allowing nutrients to be redirected to sink tissues. In a previous work, we reported that sulphur deficiency produced a delay in the leaf senescence of barley (Hordeum vulgare L.) plants, at both vegetative and reproductive stages. In this work, we analyse the effect of sulphur deficiency on the expression of several genes coding for proteases of different catalytic groups, which have been strongly associated with leaf senescence. METHODS: Four independent experiments were performed in order to impose low sulphur availability conditions: one of steady-state sulphur deficiency during the vegetative stage and three of sulphur starvation during vegetative and reproductive stages. KEY RESULTS: Sulphur deficiency inhibited or reduced the senescence-associated induction of seven of the eight proteases analysed. Their induction, as well as senescence and phloem amino acid remobilization, could be achieved with senescence inducers such as methyl-jasmonate (a hormonal stimulus) and darkness, but with different rates of induction dependent on each gene. Sulphur deficiency also exerted an opposite effect on the expression of two cysteine-protease genes (HvSAG12 and HvLEGU) as well as on one serine-protease gene (HvSUBT) according to leaf age and plant phenological stages. All three genes were induced in green leaves but were repressed in senescent leaves of sulphur-deficient plants at the vegetative stage. At the reproductive stage, both cysteine-proteases were only repressed in senescent leaves, while the serine-protease was induced in green and senescent leaves by sulphur deficiency. CONCLUSIONS: Our results highlight the relevance of adequate sulphur nutrition in order to ensure leaf senescence onset and induction of protease genes, which will consequently impact on grain protein composition and quality. In addition, our results provide evidence that leaf age, plant developmental stage and the nature of the stress modulate the sulphur responses.

Beta-Glucan and Phenolic Compounds: Their Concentration and Behavior during in Vitro Gastrointestinal Digestion and Colonic Fermentation of Different Barley-Based Food Products.

Among cereals, barley ( Hordeum vulgare L.) is notable for its high content of bioactives such as ß-glucan and phenolic compounds, but it is not used as widely in human nutrition as wheat. To compare the impact of food formulation and processing on barley bioactives, crackers, cookies, and fresh pasta were prepared combining wheat and barley flour. After quantification of ß-glucan and PCs in the barley flour and barley-based products, their behavior during in vitro gastrointestinal digestion and colonic fermentation was studied. The ß-glucan and PCs were not drastically affected by processing. The amount of bioaccessible compounds after gastrointestinal digestion was lower than the amount retained in the undigested fraction. After in vitro colonic fermentation, ß-glucan was mainly metabolized to acetic and propionic acids and PCs to phenylpropionic and phenylacetic acids. Based on the results of the study, the daily ingestion of barley-based foods may contribute to the intake of beneficial bioactive compounds.

Genetic variability in elite barley genotypes based on the agro-morphological characteristics evaluated under irrigated system / Variabilidade genética de genótipos elite de cevada com base em características morfo agronômicas avaliadas em sistema de produção irrigado

ABSTRACT Recently, researches have shown that the Brazilian savannah has a great potential to supply the demand for barley grains. The purpose of this study was to assess the genetic variability in 39 elite barley (Hordeum vulgare L.) genotypes based on the agro-morphological traits of a crop irrigated in the savannah system. An irrigation experiment in the design of complete randomized block with four replicates was conducted at Federal District - Brazil. The evaluated traits were: distance from the last knot to the rachis, distance from the flag leaf to rachis, spike length, number of grains by ear, flag leaf area, plant height, silking, lodging, grain yield, thousand-seed weight, protein content and grain commercial classification. After using analysis of variance the means were used to estimate the genetic dissimilarity among all genotypes pairs based on the Mahalanobis' generalized distance. Cluster analysis using genetic distance matrix was performed having Unweighted Pair Group Method using Arithmetic Means method (UPGMA) as the criteria. Highly significant differences were found among the genotypes for all traits evaluated. The high coefficient of genetic variation indicates the possibility of having genetic gains for all traits. The traits that most contributed to the variability were the flag leaf area and silking, while the protein content and lodging were the traits that contributed the least. Based on the cluster analysis, at least three major groups of similarity were found. There was a clustering trend of two and six-rowed materials. The most divergent genotypes were PFC 2005123, Antártica-1, Nandi and FM 404.

RESUMO Recentemente, pesquisas tem demonstrado que o Cerrado tem grande potencial para suprir a demanda de cevada. O objetivo deste trabalho foi avaliar a variabilidade genética de 39 genótipos elite de cevada com base em características morfoagronômicas avaliadas em sistema de produção irrigado no Cerrado. O experimento foi conduzido num delineamento de blocos ao acaso com quatro repetições no Distrito Federal - Brasil. Avaliaram-se as características: distância do último nó à ráquis, distância da folha bandeira à ráquis, comprimento da espiga, número de grãos por espiga, área da folha bandeira, altura de plantas, espigamento, grau de acamamento, rendimento de grãos, peso de mil sementes, teor de proteína e classificação comercial de grãos. Após análise de variância as médias foram utilizadas para estimar a dissimilaridade genética, com base na distância generalizada de Mahalanobis. Utilizando a matriz de distâncias genéticas foram realizadas análises de agrupamento. Foram observadas diferenças altamente significativas entre os genótipos para todas as características avaliadas. O elevado coeficiente de variação genético evidencia a possibilidade de obter ganhos genéticos para todas características. Através das análises de agrupamento, verificou-se a formação de pelo menos três grandes grupos de similaridade. Houve tendência de agrupamento dos materiais dísticos e hexásticos. Os genótipos PFC 2005123, Antártica-1, Nandi e FM 404 foram os mais divergentes.

High night temperatures during grain number determination reduce wheat and barley grain yield: a field study.

Warm nights are a widespread predicted feature of climate change. This study investigated the impact of high night temperatures during the critical period for grain yield determination in wheat and barley crops under field conditions, assessing the effects on development, growth and partitioning crop-level processes driving grain number per unit area (GN). Experiments combined: (i) two contrasting radiation and temperature environments: late sowing in 2011 and early sowing in 2013, (ii) two well-adapted crops with similar phenology: bread wheat and two-row malting barley and (iii) two temperature regimes: ambient and high night temperatures. The night temperature increase (ca. 3.9 °C in both crops and growing seasons) was achieved using purpose-built heating chambers placed on the crop at 19:000 hours and removed at 7:00 hours every day from the third detectable stem node to 10 days post-flowering. Across growing seasons and crops, the average minimum temperature during the critical period ranged from 11.2 to 17.2 °C. Wheat and barley grain yield were similarly reduced under warm nights (ca. 7% °C(-1) ), due to GN reductions (ca. 6% °C(-1) ) linked to a lower number of spikes per m(2) . An accelerated development under high night temperatures led to a shorter critical period duration, reducing solar radiation capture with negative consequences for biomass production, GN and therefore, grain yield. The information generated could be used as a starting point to design management and/or breeding strategies to improve crop adaptation facing climate change.

Tratamento de sementes de cevada com zinco: potencial fisiológico e produtividade de sementes / Barley seed treatment with zinc: seed physiological quality and yield

Objetivou-se no presente trabalho avaliar o efeito do tratamento de sementes de cevada com diferentes doses de zinco na qualidade fisiológica das sementes tratadas e produzidas, bem como avaliar o rendimento de sementes. Os tratamentos consistiram em combinações de sementes de duas cultivares e seis doses de zinco, em esquema fatorial 2 X 6 (Fator A: cultivares BRS Elis e BRS Cauê; Fator B: níveis de 0; 1; 2; 3; 4 e 5 mL kg-1 de semente), totalizando 12 tratamentos. O delineamento experimental utilizado foi o completamente casualizado, com quatro repetições. A qualidade fisiológica das sementes tratadas e produzidas foi avaliada por testes de vigor e de germinação, sendo que após a colheita avaliou-se o rendimento de sementes. O zinco fornecido via tratamento de sementes de cevada até a dose de 5 mL kg-1 de semente, nas cultivares BRS Elis e Cauê, não altera a qualidade fisiológica das sementes tratadas e produzidas e proporciona incremento no número de sementes e no rendimento.(AU)

The objective of this study was to evaluate treatment in barley seeds with different doses of zinc in the physiological quality of seeds produced and treated, as well as evaluate the seed yield. The treatments consisted of combinations of two cultivars and six doses of zinc, in a factorial 2 X 6 (Factor A: cv BRS Ellis and BRS Cauê; Factor B: levels 0, 1, 2, 3, 4 and 5 mL kg-1 seed), totaling 12 treatments. The experimental design was completely randomized with four replications. The physiological quality of seeds produced was treated and evaluated by tests of vigor and germination, and after harvest were evaluated seed yield. Zinc supplied via barley seeds up to a dose of 5 mL kg-1 seed, the BRS Cauê and Ellis, has no effect on seed germination and vigor of treated and produced, but gives significant increases in seed number and yield.(AU)

Agronomic performance of barley cultivars under different irrigation depths / Desempenho agronômico de cultivares de cevada cervejeira sob diferentes lâminas de irrigação

The research work aimed to evaluate the performance of barley cultivars under different irrigation depths in Brazilian Cerrado. The experiment was conducted in a split plot completely randomized design, with irrigation depths (50, 75, 100 and 125% of crop evapotranspiration) in the plots and barley cultivars (BRS Sampa, BRS Manduri and BRS 195) in the split-plots, with four replications. Barley cultivars were different regarding number of tillers per plant, number of spikelets per spike, and root depth. The maximum yields for BRS Sampa, BRS Manduri and BRS 195 were 5,848; 5,449; and 4,767 kg ha-1, respectively. BRS Sampa showed a value 17% higher than the yield reported by the holder. The irrigation depth affected all the agronomic traits. It is recommended BRS Sampa for Brazilian Cerrado, that didnt differ from other cultivars and was developed in region of similar climate; with replacement of 100% of crop evapotranspiration.(AU)

Objetivou-se avaliar o desempenho agronômico de cultivares de cevada cervejeira submetidas a diferentes lâminas de irrigação no cerrado sul-mato-grossense. O experimento foi conduzido no delineamento inteiramente casualizado, com parcelas subdivididas, tendo nas parcelas quatro lâminas de irrigação (50, 75, 100 e 125% da evapotranspiração da cultura) e nas subparcelas três cultivares de cevada (BRS Sampa, BRS Manduri e BRS 195), com quatro repetições. As cultivares de cevada diferiram apenas em número de perfilhos por planta, espiguetas por espiga e profundidade do sistema radicular. As produtividades máximas de grãos para as cultivares BRS Sampa, BRS Manduri e BRS 195 foram de 5.848, 5.449 e 4.767 kg ha-1, respectivamente. A cevada BRS Sampa apresentou valor 17% superior à produtividade divulgada pelo detentor. As lâminas de irrigação afetaram todas as características agronômicas avaliadas. Recomenda-se para o nordeste sul-mato-grossense a BRS Sampa irrigada com reposição de 100% da evapotranspiração da cultura, por não ter diferido das demais cultivares e ter sido desenvolvida para região de clima semelhante.(AU)

Agronomic performance of barley cultivars under different irrigation depths / Desempenho agronômico de cultivares de cevada cervejeira sob diferentes lâminas de irrigação

The research work aimed to evaluate the performance of barley cultivars under different irrigation depths in Brazilian Cerrado. The experiment was conducted in a split plot completely randomized design, with irrigation depths (50, 75, 100 and 125% of crop evapotranspiration) in the plots and barley cultivars (BRS Sampa, BRS Manduri and BRS 195) in the split-plots, with four replications. Barley cultivars were different regarding number of tillers per plant, number of spikelets per spike, and root depth. The maximum yields for BRS Sampa, BRS Manduri and BRS 195 were 5,848; 5,449; and 4,767 kg ha-1, respectively. BRS Sampa showed a value 17% higher than the yield reported by the holder. The irrigation depth affected all the agronomic traits. It is recommended BRS Sampa for Brazilian Cerrado, that didnt differ from other cultivars and was developed in region of similar climate; with replacement of 100% of crop evapotranspiration.

Objetivou-se avaliar o desempenho agronômico de cultivares de cevada cervejeira submetidas a diferentes lâminas de irrigação no cerrado sul-mato-grossense. O experimento foi conduzido no delineamento inteiramente casualizado, com parcelas subdivididas, tendo nas parcelas quatro lâminas de irrigação (50, 75, 100 e 125% da evapotranspiração da cultura) e nas subparcelas três cultivares de cevada (BRS Sampa, BRS Manduri e BRS 195), com quatro repetições. As cultivares de cevada diferiram apenas em número de perfilhos por planta, espiguetas por espiga e profundidade do sistema radicular. As produtividades máximas de grãos para as cultivares BRS Sampa, BRS Manduri e BRS 195 foram de 5.848, 5.449 e 4.767 kg ha-1, respectivamente. A cevada BRS Sampa apresentou valor 17% superior à produtividade divulgada pelo detentor. As lâminas de irrigação afetaram todas as características agronômicas avaliadas. Recomenda-se para o nordeste sul-mato-grossense a BRS Sampa irrigada com reposição de 100% da evapotranspiração da cultura, por não ter diferido das demais cultivares e ter sido desenvolvida para região de clima semelhante.

Tratamento de sementes de cevada com zinco: potencial fisiológico e produtividade de sementes / Barley seed treatment with zinc: seed physiological quality and yield

Objetivou-se no presente trabalho avaliar o efeito do tratamento de sementes de cevada com diferentes doses de zinco na qualidade fisiológica das sementes tratadas e produzidas, bem como avaliar o rendimento de sementes. Os tratamentos consistiram em combinações de sementes de duas cultivares e seis doses de zinco, em esquema fatorial 2 X 6 (Fator A: cultivares BRS Elis e BRS Cauê; Fator B: níveis de 0; 1; 2; 3; 4 e 5 mL kg-1 de semente), totalizando 12 tratamentos. O delineamento experimental utilizado foi o completamente casualizado, com quatro repetições. A qualidade fisiológica das sementes tratadas e produzidas foi avaliada por testes de vigor e de germinação, sendo que após a colheita avaliou-se o rendimento de sementes. O zinco fornecido via tratamento de sementes de cevada até a dose de 5 mL kg-1 de semente, nas cultivares BRS Elis e Cauê, não altera a qualidade fisiológica das sementes tratadas e produzidas e proporciona incremento no número de sementes e no rendimento.

The objective of this study was to evaluate treatment in barley seeds with different doses of zinc in the physiological quality of seeds produced and treated, as well as evaluate the seed yield. The treatments consisted of combinations of two cultivars and six doses of zinc, in a factorial 2 X 6 (Factor A: cv BRS Ellis and BRS Cauê; Factor B: levels 0, 1, 2, 3, 4 and 5 mL kg-1 seed), totaling 12 treatments. The experimental design was completely randomized with four replications. The physiological quality of seeds produced was treated and evaluated by tests of vigor and germination, and after harvest were evaluated seed yield. Zinc supplied via barley seeds up to a dose of 5 mL kg-1 seed, the BRS Cauê and Ellis, has no effect on seed germination and vigor of treated and produced, but gives significant increases in seed number and yield.

Pleiotropic effects of the sdw1 locus in barley populations representing different rounds of recombination

Background In the present study populations, representing different rounds of recombination were used for the analysis of phenotypic effects associated with the sdw1/denso locus. Other studies have mostly focused only on one type of population. Many different QTLs mapped at the same position as the sdw1/denso locus may indicate a pleiotropy of this gene or a tight linkage between genes conditioning quantitative traits. To date, results of studies have not unequivocally proven either of these two phenomena. Results Both breeding and molecular mapping experiments were undertaken to examine 200 single seed descent (SSD) and 60 doubled haploid (DH) lines obtained from the Maresi (with a semi-dwarfing gene) and Pomo cross combination. They were evaluated for the type of juvenile growth habit and certain agronomic traits were measured after harvesting. The estimates of mean values, standard errors and significance of effects were analyzed. In terms of the analyzed characteristics, the greatest variability was obtained for genotypes with the prostrate growth habit. Microsatellite markers (SSR) were also used to identify co-segregation with the sdw1/denso locus and Bmag0013, Bmag0877, Bmag0306b markers were linked the closest. A partial linkage map of chromosome 3H with the sdw1/denso semi-dwarfing gene was constructed and QTLs were identified. Conclusions Our experiments confirmed the impact of the semi-dwarfing gene on plant height, heading and flowering date both in SSD and DH populations, which may indicate pleiotropy. Moreover, a partial linkage between sdw1/denso locus and grain weight per spike and 1000-grain weight was found in the SSD population.

Genetic variability of elite barley genotypes for brazilian savanna irrigated systems based on RAPD markers / Variabilidade genética de acessos elite de cevada para sistemas irrigados no cerrado com base em marcadores RAPD

The objective of this work was to characterize and quantify the genetic variability of 39 barley elite genotypes from a Brazilian working collection belonging to Embrapa, using RAPD (Random Amplified Polymorphic DNA) molecular markers. Genomic DNA samples were extracted from leaves of each genotype and 15 decamer primers were used to obtain RAPD molecular markers. Molecular markers were converted in a binary data matrix utilized to estimate genetic dissimilarities between genotypes and to realize grouping and dispersion graphic analysis. A total of 160 RAPD markers were obtained, making 10.7 markers medium per primer. From all the markers, 141 (88.12%) were polymorphic. Genetic dissimilarities varied from 0.049 to 0.337 among the genotypes. PFC 2004033 and Prestige cultivar showed biggest genetic dissimilarities to others genetic materials. Grouping and dispersion graphic analysis showed a clustering tendency between the Mexican and American genotypes. Another clustering tendency was also found concerning the six-rowed materials. Accessions developed and used in Brazil and also in Germany, UK and Australia have shown the greatest genetic dissimilarity among themselves, being considered promising options to increase the genetic base of breeding programs.

O objetivo deste trabalho foi caracterizar e quantificar a variabilidade genética de 39 acessos de cevada elite da coleção de trabalho da Embrapa Cerrados, utilizando marcadores moleculares RAPD. Foram utilizados 15 iniciadores decâmeros para a obtenção dos marcadores RAPD, que foram convertidos em uma matriz de dados binários, a partir da qual foram estimadas as dissimilaridades genéticas entre os diferentes acessos e realizadas análises de agrupamento. Foram obtidos 160 marcadores RAPD, dos quais 141 (88,12%) foram polimórficos. As dissimilaridades genéticas variaram de 0,049 a 0,337, entre os acessos de cevada. A análise de agrupamento e de dispersão gráfica mostrou uma tendência de agrupamento entre os genótipos mexicanos e americanos. Outra tendência de agrupamento também foi encontrada entre os genótipos de seis fileiras de grãos. Acessos desenvolvidos e utilizados no Brasil e também os genótipos provenientes da Alemanha, Inglaterra e Austrália têm demonstrado a maior divergência genética entre si, sendo considerados opções interessantes para aumentar a base genética dos programas de melhoramento.

Parâmetros climáticos e variação de compostos fenólicos em cevada / Climatic parameters and variation of phenolic compounds in barley

Objetivou-se quantificar os compostos fenólicos em extrato hidroetanólico de grãos das cultivares de cevada ('BRS Lagoa' e 'MN 743') em dois anos consecutivos de cultivo (2005 e 2006), avaliando a influência dos fatores climáticos nesse conteúdo. Os compostos fenólicos totais foram quantificados pelo método de Folin-Ciocalteau e os teores de rutina e ácidos cafeico e ferúlico por CLAE em fase reversa. O conteúdo de compostos fenólicos totais variou de 0,97 a 1,59 mg AG g-1 de cevada e os fatores climáticos durante o período de plantio e colheita influenciaram no conteúdo. Foram identificados e quantificados nessas cultivares rutina, ácido cafeico e ácido ferúlico. A avaliação dos fatores climáticos no conteúdo de compostos fenólicos em cevada é de grande interesse, visando a sua importância nutricional e recomendação de cultivares com conteúdos expressivos de compostos bioativos.

This study aimed to quantify the phenolic compounds in hydroethanolic extract of cultivar seeds ('BRS Lagoa' and 'MN 743') in two consecutive years of cultivation (2005 and 2006) evaluating the influence of climatic factors in such content. The total phenolic compounds were quantified by Folin-Ciocalteau's method and the levels of rutin and caffeic and ferulic acids by HPLC in the reversed-phase. The concentration of total phenolic compounds ranged from 0.97 to 1.59 mg GA g-1 of barley and the climatic factors during the planting and harvesting influenced the barley content. Caffeic, rutin and ferulic acid were identified and quantified in these cultivars. Assessment of climatic factors on the content of phenolic compounds in barley is of great interest aiming for their nutritional importance and recommendations of cultivars with significant content of bioactive compounds.

Parâmetros climáticos e variação de compostos fenólicos em cevada

This study aimed to quantify the phenolic compounds in hydroethanolic extract of cultivar seeds ('BRS Lagoa' and 'MN 743') in two consecutive years of cultivation (2005 and 2006) evaluating the influence of climatic factors in such content. The total phenolic compounds were quantified by Folin-Ciocalteau's method and the levels of rutin and caffeic and ferulic acids by HPLC in the reversed-phase. The concentration of total phenolic compounds ranged from 0.97 to 1.59 mg GA g-1 of barley and the climatic factors during the planting and harvesting influenced the barley content. Caffeic, rutin and ferulic acid were identified and quantified in these cultivars. Assessment of climatic factors on the content of phenolic compounds in barley is of great interest aiming for their nutritional importance and recommendations of cultivars with significant content of bioactive compounds.

Objetivou-se quantificar os compostos fenólicos em extrato hidroetanólico de grãos das cultivares de cevada ('BRS Lagoa' e 'MN 743') em dois anos consecutivos de cultivo (2005 e 2006), avaliando a influência dos fatores climáticos nesse conteúdo. Os compostos fenólicos totais foram quantificados pelo método de Folin-Ciocalteau e os teores de rutina e ácidos cafeico e ferúlico por CLAE em fase reversa. O conteúdo de compostos fenólicos totais variou de 0,97 a 1,59 mg AG g-1 de cevada e os fatores climáticos durante o período de plantio e colheita influenciaram no conteúdo. Foram identificados e quantificados nessas cultivares rutina, ácido cafeico e ácido ferúlico. A avaliação dos fatores climáticos no conteúdo de compostos fenólicos em cevada é de grande interesse, visando a sua importância nutricional e recomendação de cultivares com conteúdos expressivos de compostos bioativos.

Parâmetros climáticos e variação de compostos fenólicos em cevada

This study aimed to quantify the phenolic compounds in hydroethanolic extract of cultivar seeds ('BRS Lagoa' and 'MN 743') in two consecutive years of cultivation (2005 and 2006) evaluating the influence of climatic factors in such content. The total phenolic compounds were quantified by Folin-Ciocalteau's method and the levels of rutin and caffeic and ferulic acids by HPLC in the reversed-phase. The concentration of total phenolic compounds ranged from 0.97 to 1.59 mg GA g-1 of barley and the climatic factors during the planting and harvesting influenced the barley content. Caffeic, rutin and ferulic acid were identified and quantified in these cultivars. Assessment of climatic factors on the content of phenolic compounds in barley is of great interest aiming for their nutritional importance and recommendations of cultivars with significant content of bioactive compounds.

Objetivou-se quantificar os compostos fenólicos em extrato hidroetanólico de grãos das cultivares de cevada ('BRS Lagoa' e 'MN 743') em dois anos consecutivos de cultivo (2005 e 2006), avaliando a influência dos fatores climáticos nesse conteúdo. Os compostos fenólicos totais foram quantificados pelo método de Folin-Ciocalteau e os teores de rutina e ácidos cafeico e ferúlico por CLAE em fase reversa. O conteúdo de compostos fenólicos totais variou de 0,97 a 1,59 mg AG g-1 de cevada e os fatores climáticos durante o período de plantio e colheita influenciaram no conteúdo. Foram identificados e quantificados nessas cultivares rutina, ácido cafeico e ácido ferúlico. A avaliação dos fatores climáticos no conteúdo de compostos fenólicos em cevada é de grande interesse, visando a sua importância nutricional e recomendação de cultivares com conteúdos expressivos de compostos bioativos.

Conversion of barley SNPs into PCR-based markers using dCAPS method.

Molecular genetic research relies heavily on the ability to detect polymorphisms in DNA. Single nucleotide polymorphisms (SNPs) are the most frequent form of DNA variation in the genome. In combination with a PCR assay, the corresponding SNP can be analyzed as a derived cleaved amplified polymorphic sequence (dCAPS) marker. The dCAPS method exploits the well-known specificity of a restriction endonuclease for its recognition site and can be used to virtually detect any SNP. Here, we describe the use of the dCAPS method for detecting single-nucleotide changes by means of a barley EST, CK569932, PCR-based marker.

Conversion of barley SNPs into PCR-based markers using dCAPS method

Molecular genetic research relies heavily on the ability to detect polymorphisms in DNA. Single nucleotide polymorphisms (SNPs) are the most frequent form of DNA variation in the genome. In combination with a PCR assay, the corresponding SNP can be analyzed as a derived cleaved amplified polymorphic sequence (dCAPS) marker. The dCAPS method exploits the well-known specificity of a restriction endonuclease for its recognition site and can be used to virtually detect any SNP. Here, we describe the use of the dCAPS method for detecting single-nucleotide changes by means of a barley EST, CK569932, PCR-based marker.

Genotypic differences in proembryoid development and green plantlets regeneration through androgenesis in barley varieties / Diferenças genotípicas no desenvolvimento de pró-embrióides e regeneração de plântulas verdes via androgênese em genótipo de cevada

The development of in vitro haploid plants followed by spontaneous or induced genome duplication allows to achieve, in one generation, the recovery of total homozygosis. The efficiency of the haplodiploidization process through in vitro anther culture of barley is variable among genotypes. This study was aimed at determining the androgenetic response of nine barley genotypes from the breeding program of Embrapa Trigo, analysing proembryoid development and green plantlets regeneration in anthers cultivated in vitro. Cultivar 'BR2' presented the highest average of proembryoids (104/anther) and 'MN698' presented the highest average of green plantlets (0,41/anther). There was a significant variation among the average values of barley genotypes for embryo formation and green plantlets regeneration, making possible the selection to combine androgenetic capacity and good agronomic traits.

A obtenção, na cevada, de plantas haplóides in vitro e a posterior duplicação natural ou artificial do genoma permitem alcançar a homozigose completa, em uma geração. A eficiência da haplodiploidização pela cultura de anteras é variável entre os genótipos. Foi avaliada a resposta androgenética através da formação de pró-embrióides e da regeneração de plântulas verdes em nove cultivares do programa de melhoramento de cevada da Embrapa Trigo, em anteras cultivadas in vitro. A cultivar "BR2" apresentou maior média de pró-embrióides (104/antera), enquanto "MN698" mostrou a maior média de plântulas verdes (0,41/antera). Houve variação significativa entre os valores médios dos genótipos em relação à formação de pró-embrióides e à regeneração de plântulas verdes, indicando a possibilidade de seleção para combinar a capacidade androgenética com boas características agronômicas.

Genotypic differences in proembryoid development and green plantlets regeneration through androgenesis in barley varieties / Diferenças genotípicas no desenvolvimento de pró-embrióides e regeneração de plântulas verdes via androgênese em genótipo de cevada

The development of in vitro haploid plants followed by spontaneous or induced genome duplication allows to achieve, in one generation, the recovery of total homozygosis. The efficiency of the haplodiploidization process through in vitro anther culture of barley is variable among genotypes. This study was aimed at determining the androgenetic response of nine barley genotypes from the breeding program of Embrapa Trigo, analysing proembryoid development and green plantlets regeneration in anthers cultivated in vitro. Cultivar 'BR2' presented the highest average of proembryoids (104/anther) and 'MN698' presented the highest average of green plantlets (0,41/anther). There was a significant variation among the average values of barley genotypes for embryo formation and green plantlets regeneration, making possible the selection to combine androgenetic capacity and good agronomic traits.(AU)

A obtenção, na cevada, de plantas haplóides in vitro e a posterior duplicação natural ou artificial do genoma permitem alcançar a homozigose completa, em uma geração. A eficiência da haplodiploidização pela cultura de anteras é variável entre os genótipos. Foi avaliada a resposta androgenética através da formação de pró-embrióides e da regeneração de plântulas verdes em nove cultivares do programa de melhoramento de cevada da Embrapa Trigo, em anteras cultivadas in vitro. A cultivar "BR2" apresentou maior média de pró-embrióides (104/antera), enquanto "MN698" mostrou a maior média de plântulas verdes (0,41/antera). Houve variação significativa entre os valores médios dos genótipos em relação à formação de pró-embrióides e à regeneração de plântulas verdes, indicando a possibilidade de seleção para combinar a capacidade androgenética com boas características agronômicas.(AU)

Teor de proteínas nos grãos em resposta à aplicação de nitrogênio em diferentes estádios de desenvolvimento da cevada / Protein content in barley seeds affected by nitrogen application in different growth stages

O presente trabalho teve como objetivo avaliar o teor de proteínas em grãos de cevada em resposta à aplicação de N em estádios de desenvolvimento da cultura. Os experimentos foram conduzidos em Eldorado do Sul e Encruzilhada do Sul, no ano de 2000, e em Victor Graeff, nos anos de 2000 e 2001, em delineamento experimental em blocos casualizados com quatro repetições. Os estádios de aplicação de N foram na emergência das plântulas; na emissão da 2ª ou 3ª folha; da 4ª ou 5ª folha; 6ª ou 7ª folha; 8ª ou 9ª folha; e no emborrachamento. As doses de N foram de 30 ou 40kg ha-1 e 60 ou 80kg ha-1, para a menor e maior dose, respectivamente. As determinações realizadas foram teor de proteínas nos grãos e número de grãos metro-2. Para os experimentos realizados em 2000, a aplicação de nitrogênio até o início do alongamento dos entrenós (emissão da 7ª folha) manteve o teor de proteínas no grão abaixo dos 12 por cento, mesmo para a maior dose de N. Os teores de proteínas no grão em Victor Graeff, no ano de 2001, ficaram acima do limite máximo de 12 por cento com a aplicação da maior dose de N já em estádios iniciais de desenvolvimento da cultura, devido ao maior teor de matéria orgânica no solo em relação aos outros locais.

This study was was aimed at evaluating the protein content in barley seeds affected by nitrogen application in different growth stages. Experiments were carried out in Eldorado do Sul and Encruzilhada do Sul, in 2000, and Victor Graeff, in 2000 and 2001, on a randomized blocks scheme with four repetitions. The growth stages of N application were in emergency of seedlings; emission of 2nd or 3rd leaf; 4th or 5th leaf; 6th or 7th leaf; 8th or 9th leaf; and in boot stage. The N rates were 30 or 40kg ha-1 and 60 or 80kg ha-1, for smallest and largest N rate, respectively. The protein content in barley seeds and the number of grains area-1 were determined. In the experiments carried out in 2000 the nitrogen application until the beginning of the internodes elongation maintained the seeds protein content below of 12 percent, inclusive in the largest N rate. The seeds protein content in Victor Graeff, 2001, surpassed the maximum limit of 12 percent with N applications in initial growth stages, decurrently of the higher soil organic matter content in relation to others experiments.

Incremento da sobrevivência de colmos em cevada através da adubação nitrogenada no período de alongamento dos colmos / Shoots survival increment in barley by nitrogen supply in the shoots elongation stage

O trabalho teve como objetivos avaliar o acúmulo de matéria seca (MS) e de nitrogênio (N) da parte aérea de plantas de cevada e a taxa de sobrevivência de colmos em função da época de aplicação de N. Um experimento foi realizado em Eldorado do Sul, RS, em 2000, testando seis épocas de aplicação de N (emergência das plântulas, emissão da 3ª folha, 5ª folha, 7ª folha, 9ª folha do colmo principal (CP) e no emborrachamento) e duas doses de N (40 e 80kg ha-1). Foram determinados os acúmulos de MS e N da parte aérea no período entre o início do alongamento dos colmos e o florescimento e a taxa de sobrevivência de colmos. As aplicações de N entre a emergência das plântulas e a emissão da 9ª folha do CP resultaram nas maiores taxas de acúmulo de MS. Entretanto, as maiores taxas de acúmulo de N foram observadas com a aplicação de N no período de alongamento dos colmos. As maiores porcentagens de sobrevivência de colmos também foram observadas com a aplicação de N nesse período, mostrando a relação existente entre a necessidade de N para dar aporte ao alongamento dos colmos e a mortalidade de afilhos.

This study was aimed at evaluating the dry matter (DM) and nitrogen (N) accumulation in aerial part of barley plants and the shoot survival rate in function of time of N supply. An experiment was carried out in Eldorado do Sul, RS, in 2000, where six times of N supply (seedling emergence; 3rd leaf; 5th leaf; 7th leaf; 9th leaf emergence and boot stage) and two N rates (40 and 80kg ha-1) were tested. The DM and N accumulation among the shoot elongation begin and the bloom stage and the shoot survival rate were determined. The N supply among seedling emergence and 9th leaf emergence stage resulted the largest DM rates accumulations. However, the largest N rates accumulations were observed in shoot elongation period. The largest shoot survival rates were also observed in this period, showing the relation among the N necessity to support the shoot elongation process and the shoot mortality.