RESUMO O objetivo foi avaliar a divergência genética entre acessos de espécies silvestres e híbridos interespecíficos F1 de tomateiro. Caracterizou-se seis acessos silvestres (Solanum pimpinellifolium ‘AF 26970’, S. galapagense ‘LA-1401’, S. peruvianum ‘AF 19684’, S. habrochaites var. hirsutum ‘PI-127826’, S. habrochaites var. glabratum ‘PI-134417’ e S. pennellii ‘LA-716’), a cultivar comercial Redenção e os respectivos híbridos interespecíficos F1: ‘Redenção’ x ‘AF 26970’, ‘Redenção’ x ‘LA-1401’, ‘Redenção’ x ‘AF 19684’, ‘Redenção’ x ‘PI-127826’, ‘Redenção’ x ‘PI-134417’ e ‘Redenção’ x ‘LA-716’. Foram avaliados 35 caracteres quantitativos, sendo 29 morfoagronômicos e seis fisiológicos. Realizou-se análises de componentes principais (ACP). Utilizou-se os métodos de otimização de Tocher, baseado na distância de Mahalanobis e a dispersão gráfica das variáveis canônicas, que seguiram a mesma tendência de agrupamento dos genótipos, formando três grupos distintos. As ACP permitiram observar algumas divergências genéticas não observadas pelos demais métodos. Ocorreu alta divergência entre os acessos das espécies e híbridos interespecíficos. A cultivar Redenção teve a maior dissimilaridade genética e os híbridos interespecíficos de S. lycopersicum com acessos silvestres, apresentaram maior similaridade morfoagronômica e fisiológica com os genitores silvestres.

ABSTRACT The objective of this study was to evaluate the genetic divergence among accessions of wild tomato species and interspecific F1 hybrids. Six wild accessions were characterized (Solanum pimpinellifolium ‘AF 26970’, S. galapagense ‘LA-1401’, S. peruvianum ‘AF 19684’, S. habrochaites var. hirsutum ‘PI-127826’, S. habrochaites var. glabratum ‘PI-134417’, and S. pennellii ‘LA-716’), the commercial cultivar Redenção, and the respective interspecific F1 hybrids: ‘Redenção’ x ‘AF 26970’, ‘Redenção’ x ‘LA-1401’, ‘Redenção’ x ‘AF 19684’, ‘Redenção’ x ‘PI-127826’, ‘Redenção’ x ‘PI-134417’, and ‘Redenção’ x ‘LA-716’. Thirty-five quantitative traits were evaluated, encompassing 29 morphoagronomic and six physiological characteristics. Principal component analysis (PCA) was performed. Tocher’s optimization method was used based on the Mahalanobis distance and the graphic dispersion of canonical variables, which followed the same trend of genotype clustering, forming three distinct groups. The PCA indicated some genetic divergences not shown by the other methods. A high divergence was observed among the species accessions and interspecific hybrids. The cultivar Redenção had the greatest genetic dissimilarity, and the interspecific hybrids of S. lycopersicum with wild accessions showed the greatest morphoagronomic and physiological similarity with the wild parents.

Abstract This research shows two new microalloyed steels with niobium (Nb) for railroad wheels (Nb1 and Nb2) applied on heavy haul transportation (load over 30 tons/axle). The steels have mixed microstructure composed of pearlite and bainite (finished wheel rim section), and another one composed of martensite with bainite (black wheel section removed on machining) obtained by continuous cooling quenching heat treatment followed by tempering. The bainitic and martensitic microstructure are sensitive to the temper embrittlement phenomenon; therefore, knowing the embrittlement temperature range of these steels is mandatory in order to avoid such an event in the tempering process. Charpy specimens were extracted from the rim of railroad wheels, austenitized (860 ºC), quenched in water for four minutes, and tempered at different temperatures to obtain the embrittlement curve. Three materials were compared: AAR (Association of American Railroads) Class C steel with pearlitic microstructure (not sensitive to embrittlement), Nb1, and Nb2 microalloyed steels with martensitic, bainitic, and pearlitic microstructures. The microalloyed steels have niobium (Nb), molybdenum (Mo), and silicon (Si) addition. The effect of Si content and the microstructure (analyzed by Scanning Electronic Microscope (SEM)), regarding the embrittlement phenomenon, was also studied. The microstructure of Nb2 steel was analyzed by with Transmission Electronic Microscope (TEM) for improving its characterization.

In response to the outbreak of the novel Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), pathogen of the new coronavirus disease (COVID-19), several sectors and social activities have been affected, including education. At first, it is explained that educators and students can feel fragile during and after the SARS-CoV-2 outbreak. Subsequently, it is discussed that their relationship ought to be carefully established given the triggering of psychological and neuropsychiatric effects arising from neural coding and plasticity processes, which result in the formation of positive and negative memories in the short to long term. Finally, it is pointed out that the SARS-CoV-2 pandemic generates a need for adequacy and adaptation for the significant attention to students during the re-starting of studies, given that possible disorders of sensory modulation and involvement of limbic brain areas triggered in situations of risk of death, potential or real threat, can happen. It is assumed that at times of the SARS-CoV-2 pandemic, in addition to preserving life, one of the challenges is the behavioural (re)organisation, which includes habits from the educational context that need to contemplate a scientific perspective, seeking to transform the consequences of the pandemic fear on opportunities to reinforcement of familiar links. In the context of modern rationality, the SARS-CoV-2 pandemic is also a period to think about the relationship between scientific knowledge and common sense. With this logic, neurosciences can develop a new format for the teaching-learning process, so that educators and students experiencing the pandemic threatening do not manifest psychological distress and secondary consequences. Therefore, education can be considered a central space in decision-making in the face of SARS-CoV-2 pandemic. In this sense, the urgency of a multidisciplinary strategies development is highlighted, connecting the synergy between neurosciences and education after the COVID-19 pandemic.

ABSTRACT Introduction: Immediate breast reconstruction plays an important role in the treatment of breast cancer and relatively promotes patients’ emotional and physical recovery. It may be difficult to cover the entire prosthesis with a muscle flap in single-stage breast reconstructions based on a permanent implant. This study aimed to present a muscle pocket for the implant using a reverse anterior serratus muscle flap associated with submuscular dissection of the pectoralis major muscle. Methods: This was a prospective study comprising 61 patients undergoing mastectomy followed by immediate reconstruction (74 reconstructions) with implant and anterior serratus muscle reverse flap associated with submuscular pectoralis dissection between January 2017 and July 2018. In this study, age, adjuvant and neoadjuvant therapies, implant volume, length of hospital stay, follow-up, and complications, including functional deficit and reconstruction failure, were analyzed. Results: The technique described was used to operate 74 patients with a mean age of 49.2 years. The volume of the implant varied from 200 to 500 cc, and the mean follow-up time was 14.9 months. Complications such as hematoma, suture dehiscence, skin flap necrosis, and implant extrusion were observed in 14 patients (18.9%). Conclusion: In most cases, breast reconstruction with an anterior serratus muscle reverse flap associated with submuscular dissection of the pectoralis major muscle allows the complete muscle coverage of the implant, reduces the occurrence of major surgical complications, and has a good aesthetic result.

RESUMO Introdução: A reconstrução mamária imediata desempenha papel importante no tratamento do câncer de mama, permitindo uma recuperação emocional e física, ainda que parcial, das pacientes. Nas reconstruções mamárias em único estágio, baseada em implante permanente, pode ser difícil cobrir toda a prótese com retalho muscular. O objetivo do estudo é apresentar a realização de uma bolsa muscular para implante através do retalho reverso do músculo serrátil anterior associada à dissecção submuscular do músculo peitoral maior. Métodos: Foi realizado um estudo prospectivo com 61 pacientes submetidas à mastectomia seguida de reconstrução imediata (74 reconstruções) com implante e retalho reverso do músculo serrátil anterior associado à dissecção submuscular do peitoral, entre janeiro de 2017 e julho de 2018. Foram analisados a idade, terapia adjuvante e neoadjuvante, volume do implante, tempo de internação hospitalar, seguimento e complicações, incluindo déficit funcional e falha na reconstrução. Resultados: 74 pacientes foram operadas pela técnica descrita com idade média de 49,2 anos. O volume do implante variou de 200 a 500cc e o tempo médio de proservação foi de 14,9 meses. 14 pacientes (18,9%) apresentaram complicações como hematoma, deiscência de sutura, necrose de retalho cutâneo e extrusão do implante. Conclusão: A reconstrução mamária com retalho reverso do músculo serrátil anterior associado à dissecção submuscular do peitoral maior permite, na grande maioria dos casos, cobertura muscular completa do implante, redução de complicações cirúrgicas maiores e bom aspecto estético.

Abstract Ten-year seasonal climate reforecasts over South America are obtained using the Eta Regional Climate Model at 40 km resolution, driven by the large-scale forcing from the global atmospheric model of the Center for Weather Forecasts and Climate Studies. The objective of this work is to evaluate these regional reforecasts. The dataset is comprised of four-month seasonal forecasts performed on a monthly basis between 2001 and 2010. An ensemble of five members is constructed from five slightly different initial conditions to partially reduce the uncertainty in the seasonal forecasts. The seasonal mean precipitation and 2-meter temperature forecasts are compared with the observations. The comparison shows that, in general, forecasted precipitation is underestimated in the central part of the continent in the austral summer, whereas the forecasted 2 meter temperature is underestimated in most parts of the continent and throughout the year. Skill scores show higher skill in the northern part of the continent and lower skill in the southern part of the continent, but mixed skill signs are seen in the central part of the continent. During the El Niño and La Niña seasons, the forecast skill scores clearly increase. The downscaling of the Eta model seasonal forecasts provides added value over the driver global model forecasts, especially during rainy periods.

This study aimed at evaluating the effect of ractopamine (RAC) on metabolism, zootechnical performance, body composition, and behavior in Wistar rats submitted to acute and chronic restrain stress. The oral dose of 5 mg/kg of RAC was administered in periods of 0, 7, 14, 21, and 28 days. The elevated plus-maze test (EPMT) was used for behavioral assessment. Blood, carcass and viscera characteristics were evaluated. Insulin-dependent glucose transporters (GLUT-4) were semi-quantified by Western Blot in epididymal adipocytes. RAC periods associated with chronic stress increased the GLUT-4 protein expression in adipose tissue in a time-dependent manner (P=0.01), i.e., the longer the RAC addition period, the higher the GLUT-4 concentration in chronically stressed animals (0=1.42; 7=1.19; 14=2.03; 21=1.59; 28=2.35). The stress periods combined with RAC increased the time spent in the opened arms of the maze (Chronic stress: 0=10.6; 7=8.7; 14=5.9; 21=12.3; 28=4.0; Acute stress 0=3.1; 7= 4.7; 14=7.5; 21=0.0; 28=2.8) (P=0.04). Chronic (entries on the closed arms [ECA]=3.60) and acute (ECA=3.80) stress reduced locomotive activity in the maze (P=0.03). The results suggested that stress could negatively affect the possible benefits offered by the RAC, mainly impairing the adipose tissue metabolism and behavior in the animals.

Com o objetivo de avaliar o efeito do condicionamento fisiológico e da qualidade de sementes sobre a época de florescimento de plantas de milho, foi realizado o presente trabalho. Foram utilizados lotes de sementes com qualidade fisiológica distinta de duas linhagens. Parte das sementes de cada lote foi condicionada em água, por período de 24 horas, totalizando quatro tratamentos, os quais foram avaliados na ausência e presença do "split" (sincronia de plantio) recomendado. Na área experimental, cada parcela foi composta por seis linhas de quatro metros cada uma, seguindo o delineamento de blocos casualizados com quatro repetições. Foram avaliadas a porcentagem da emergência das plantas em campo, altura das plantas, as datas em que ocorreram 50% e 100% de liberação do pólen e de emissão do estilo-estigma e, ainda, a data da ausência de liberação de pólen das plantas do parental masculino e receptividade do estilo-estigma para as do parental feminino e a data em que as sementes estavam no estádio de desenvolvimento LL3. Quando foram utilizadas sementes com alta qualidade e sem condicionamento, não houve necessidade de se efetuar o "split". O mesmo ocorreu com sementes não condicionadas e com alta qualidade do parental mais tardio, associadas com sementes de baixa qualidade e condicionadas do parental mais precoce. Foi observado, também, que a diferença existente no florescimento dos parentais praticamente se estendeu até o desenvolvimento das sementes no estádio LL3.

In order to evaluate the effect of priming and physiological seed quality on maize flowering aiming the production of hybrid seeds, the following experimental procedure was carried out. Seed lots with distinct physiological quality of two lines were used. Part of each seed lot obtained was primed in water for 24 hours on a total of four treatments, which were evaluated in the presence and absence of the recommended split. In the experimental field, each plot was composed of six lines of four meters each, following the experimental design which consisted of a randomized complete block in four replications. The following variables were measured: percentage of field emergence, plant height, dates when 50% and 100% of pollen release and the emission of "stigma-style" occurred; moreover the date of no pollen release of male parent and receptivity of "stigma-style" towards the female parent and the date when the seeds were at stage ML 3 of development. When high quality seeds and no priming were used, it was not necessary to use the split. The same happened to high quality non-primed seeds of the later parent associated with low quality and primed seeds of the earlier parent. It was also observed that the difference in flowering date between the parents extended until the date of ML 3.

A micropropagação de anonáceas poderá contribuir para a obtenção de plantios mais homogêneos e a inserção de novas espécies em sistemas produtivos. Entretanto, plantas cultivadas in vitro freqüentemente exibem alterações anatômicas e sua quantificação poderá auxiliar na obtenção de protocolos de cultivo mais eficientes. Realizou-se neste trabalho o estudo comparativo da anatomia foliar de seis espécies de anonáceas cultivadas in vitro e em casa de vegetação. Annona coriacea foi a única espécie que não apresentou variação na densidade e na dimensão dos estômatos quando cultivada in vitro, enquanto que, Annona bahiensis, Annona glabra, Annona squamosa e Rolinia silvatica apresentaram aumento na densidade estomática e na redução na espessura das epidermes foliares nesse tipo de cultivo.

Micropropagation of Annonaceae can produce homogeneous plants and bring new species into commercial production. Plants cultivated in vitro, however, frequently demonstrate anatomical alterations, and the quantification of these changes should aid in determining more efficient culture protocols. The present work undertook a comparative study of the leaf anatomy of six species of Annonaceae cultivated in vitro and in greenhouses. Annona coriacea was the only species that did not show variations in the density or the dimensions of their stomata when cultivated in vitro, while Annona bahiensis, Annona glabra, Annona squamosa, and Rolinia silvatica demonstrated increases in leaf stomatal density and a reduction of the leaf epidermis under these conditions.

A baixa sobrevivência durante a aclimatização de plantas regeneradas através da micropropagação tem sido atribuída, entre vários fatores, à baixa capacidade fotossintética. O desenvolvimento de protocolos que utilizem sistemas de cultivo in vitro fotoautotróficos surgem como possibilidades potenciais para aumentar a eficiência da micropropagação. Objetivou-se, neste trabalho comparar as medições dos tecidos foliares de plantas de Annona glabra L. cultivadas in vitro, sob condições de estímulo ao fotoautotrofismo e heterotróficas, durante a fase de enraizamento, com plantas ex vitro (mantidas sob radiação fotossintética ativa de 130-170µmol.m-2.s-1, sem controle de temperatura). As brotações foram enraizadas em condições de estímulo ao fotoautotrofismo (meio sem sacarose e com aeração) e em condições heterotróficas (meio com sacarose e sem aeração). O meio de cultivo utilizado foi o WPM adicionado de 164,4mM de carvão ativado e 4,9µM AIB. Após 30 dias de cultivo realizaram-se medições das espessuras das epidermes abaxial, adaxial, parênquima esponjoso, paliçadico e do limbo. Verificaram-se variações na anatomia das folhas, que foram caracterizadas por um aumento na espessura foliar de acordo com a aeração estabelecida. O enraizamento de plantas de A. glabra em condições de estímulo ao fotoautotrofismo permitiu desenvolvimento anátomo-fisiológico semelhante àquele observado em condições ex vitro, o que pode minimizar as perdas no processo de micropropagação.

The low survival during the acclimatization of plants regenerated through the micropropagation has been attributed, among several factors, to low the photosynthetic capacity. The development of photoautotrophic in vitro culture systems appears as potential possibilities of increasing the efficiency of the micropropagation. The aim of this work was to compare the leaf anatomy of plants of Annona glabra L. cultivated in vitro, under photoautotrophic and heterotrophic conditions, during the phase of rooting, with ex vitro (maintained in greenhouse under photosynthetic acitve radiation of 130-170µmol.m-2.s-1, without control of room temperature). Shoots were rooted in photoautotrophic conditions (sucrose-free medium with aeration) heterotrophic conditions (medium with sucrose without ventilation). The medium of culture was the WPM supplied of 164.4mM of activated charcoal and 4.9µM AIB. After 30 days of culture measurements of the foliar thickness of the epidermises abaxial, adaxial, parenchyma spongy, palisade and limb one. Verified variations in the anatomy of the leaves, that had been characterized by an increase in the leaf thickness in accordance with the established aeration. In vitro photoautotrophic rooting of plants Annona glabra L stimulated an anatomical and physiological development similar to the one observed in an ex vitro condition, which may minimize the losses at the acclimatization process.

A síndrome de Wells é dermatose inflamatória benigna rara, de curso recorrente, descrita em todas as idades e sem predileção por sexo, de etiologia e patogênese desconhecidas. Embora sua autonomia seja questionada, a síndrome de Wells é entidade distinta cujo diagnóstico se faz pela combinação de quadro clínico marcante, achados histopatológicos típicos quando associados à clínica, e curso característico.

Wells’ syndrome is a rare, benign, recurrent, inflammatory dermatosis affecting all age groups, with no sex predilection. Its etiology and pathogenesis remain unknown. Although its autonomous existence is questioned by some, Wells’ syndrome is a distinct disease entity diagnosed by the combination of a striking clinical picture, typical histological finding when associated to the clinical features, and a characteristic time course.

Franciscanas foram utilizadas como fonte de informação sobre a biodisponibilidade de cádmio em águas neríticas da Costa Sul do Brasil. Amostras de fígado, obtidas de 44 indivíduos capturados acidentalmente ao largo da costa do Rio Grande do Sul, foram analisadas através de EAA eletrotérmica. Concentrações de cádmio, idade, peso e comprimento totais dos golfinhos analisados variaram entre 39 e 4144 µg.kg-1 (peso úmido), um e cinco anos, 17,5 e 49,2 kg, e entre 105,3 e 156,8 cm, respectivamente. Em relação às concentrações hepáticas de cádmio em franciscanas, não houve diferença significativa entre os dados gerados pelo presente estudo e informação proveniente da literatura, referente ao Estado do Rio de Janeiro. As baixas concentrações de cádmio observadas podem ser atribuídas ao fato de as lulas da Família Loliginidae constituírem a principal presa para franciscanas, dentre os cefalópodes. Este estudo corrobora investigações sobre níveis de cádmio em lulas brasileiras e reforça a hipótese de que cefalópodes loliginídeos não constituem vetores importantes da transferência de cádmio para cetáceos.

Franciscana dolphins were used as source of information on the bioavailability of cadmium in the neritic waters off South Brazilian Coast. Liver samples obtained from 44 individuals incidentally captured off Rio Grande do Sul State were analyzed by electrothermal AAS. Cadmium concentrations, age, total weight and length of the analyzed dolphins varied between 39 and 4144 µg.kg-1 (wet weight), one and five years, 17.5 and 49.2 kg, and between 105.3 and 156.8 cm, respectively. Concerning hepatic cadmium concentrations of franciscanas, there was no significant difference between data raised by the present study and information from literature, regarding Rio de Janeiro State. The low cadmium concentrations observed may be attributed to the fact that loliginid squids constitute the main cephalopod prey for franciscanas. This study corroborates investigations on cadmium levels in Brazilian squids and strengthened the hypothesis that cephalopods of Loliginidae Family do not constitute important vectors of the transfer of cadmium to cetaceans.

Infecções virais em alho são normalmente causadas por um complexo viral. Neste estudo, um complexo viral de alho, coletado em campo, em três regiões geográficas, foi testado com anti-soros monoclonais específicos para Garlic virus A (GarV-A), Garlic virus B (GarV-B), Garlic virus C (GarV-C) e um anti-soro policlonal capaz de detectar os três vírus mencionados e Garlic virus D (GarV-D). Procedeu-se à amplificação por transcriptase reversa-reação em cadeia da polimerase (RT-PCR) usando oligonucleotídeos sintetizados a partir de regiões específicas de genes de proteínas capsidiais de allexivirus japoneses e disponíveis no GeneBank (National Center of Biotechnology Information - NCBI). Por esse procedimento, vírus individuais foram isolados e seqüenciados. Os vírus detectados foram biologicamente isolados por meio de sucessivas inoculações em Chenopodium quinoa. A análise das seqüências de nucleotídeos, de aminoácidos e os resultados sorológicos revelaram a presença de três espécies distintas de allexivirus GarV-C, GarV-D e Garlic mite-borne filamentous virus (GarMbFV) no Brasil.

Garlic viruses often occur in mixed infections under field conditions. In this study, garlic samples collected in three geographical areas of Brazil were tested by Dot-ELISA for the detection of allexiviruses using monoclonal specific antibodies to detect Garlic virus A (GarV-A), Garlic virus B (GarV-B), Garlic virus C (GarV-C) and a polyclonal antiserum able to detect the three virus species mentioned plus Garlic virus D (GarV-D). The detected viruses were biologically isolated by successive passages through Chenopodium quinoa. Reverse Transcriptase Polimerase Chain Reaction (RT-PCR) was performed using primers designed from specific regions of the coat protein genes of Japanese allexiviruses available in the Genetic Bank of National Center of Biotechnology Information (NCBI). By these procedures, individual garlic virus genomes were isolated and sequenced. The nucleotide and amino acid sequence analysis and the one with serological data revealed the presence of three distinct allexiviruses GarV-C, GarV-D and a recently described allexivirus, named Garlic mite-borne filamentous virus (GarMbFV), in Brazil.

A presença de aglutininas anti-Leptospira spp. em 1360 amostras soros de ovinos, clinicamente sadios com mais de um ano de idade, criados extensivamente em 136 fazendas de 18 municípios; 10 na Mesorregião Sudeste e 8 na Mesorregião Sudoeste do Estado do Rio Grande do Sul, entre os meses de janeiro a março de 1999. Foi determinado pela Técnica de Aglutinação Microscópica (MAT), das 1360 amostras de soros testados, 466 (34,26%) animais foram reagentes e os títulos de aglutininas anti-Leptospira spp. variavam de 100 a 3200. As sorovariedades encontradas foram: hardjo (Norma), 210 (28,4%), sentot, 152 (16,8%); hardjoprajitno, 133 (14,5%); fortbragg 73 (6,3%), wolffi, 39 (4,7%); pyrogenes, 25 (1,8%); australis, 21 (1,6%); pomona, 20 (1,6%); sejroe, 19 (2,2%); castellonis, 18(1,8%); hebdomadis, 17 (1,3%); icterohaemorrhagiae, 16 (0,5%); grippotyphosa, 9 (0,7%); canicola, 8 (0,6%); tarassovi, 7 (0,6%), bratislava, 4 (0,29%), autumnalis, 3 (0,2%). Os resultados mostraram que as Leptospira spp. estão disseminadas na maioria das fazendas que criam ovinos nas Mesorregiões Sudeste e Sudoeste do Rio Grande do Sul.

The presence of anti-Leptospira agglutinins in 1.360 samples of ovine sera was determined. Clinically healthy sheep with more than one year of age, raised in pasture in 136 farms of 18 counties, 10 located in the southeast Mesorregions and 8 in the southwest Mesorregions of the state of Rio Grande do Sul, Brazil, between the months of January and March of 1999. Were used sera tested by the Microscopic Agglutination Technique (MAT), from the 1.360 samples of serum tested, 466 (34.26%) were positive and the titers of anti-Leptospira spp. agglutinins varied from 100 to 3.200. The serovars founded were: hardjo (Norma), 210 (28.4%), sentot, 152 (16.8%); hardjoprajitno, 133 (14.5%); fortbragg, 73 (6.3%); wolffi, 39 (4.7%); pyrogenes, 25 (1.8%); australis, 21 (1.6%); pomona, 20 (1.6%); sejroe, 19 (2.2%); castellonis, 18 (1.8%); hebdomadis, 17 (1.3%); icterohaemorrhagiae, 16 (0.5%); grippotyphosa, 9 (0.7%); canicola , 8 (0.6%); tarassovi, 7 (0.6%), bratislava, 4 (0.29%), autumnalis, 3 (0.2%). The results demonstrate that Leptospira spp are disseminated in the majority of the farms that raise sheep in the southeast and southwest Mesorregions of the State of Rio Grande do Sul, Brazil.

Infecções virais em alho são normalmente causadas por um complexo viral. Neste estudo, um complexo viral de alho, coletado em campo, foi purificado. Procedeu-se à amplificação por RT-PCR usando oligonucleotídeos desenhados para regiões-consenso dos genes das proteínas capsidiais de Onion yellow dwarf virus, estirpe do alho e de Leek yellow stripe virus. cDNA de Garlic common latent virus foi sintetizado usando oligo-dT e oligonucleotídeos aleatórios. Por estes procedimentos clones de diferentes espécies virais foram isolados e sequenciados. A análise das sequências nucleotídicas e os resultados sorológicos revelaram a presença dos Potyvirus OYDV-G e LYSV e do Carlavirus GCLV, simultaneamente infetando plantas de alho. As seqüências de aminoácidos deduzidos dos isolados brasileiros foram comparadas com aquelas de vírus relacionados, relatados em diferentes regiões do mundo. A análise mostrou pequena variabilidade em relação aos isolados brasileiros de OYDV-G e GCLV, e maior divergência em relação ao isolado de LYSV. A detecção destas espécies virais também foi obtida por reações específicas observadas quando o gene da proteína capsídica dos isolados brasileiros foi usado como sonda em ensaios de hibridização do tipo dot-blot e Southern blot. Em campo, a re-infecção natural de alho livre de vírus foi avaliada.

Garlic viruses often occur in complex infections in nature. In this study, a garlic virus complex, collected in fields in Brazil, was purified. RT-PCR was performed using specific primers designed from the consensus regions of the coat protein genes of Onion yellow dwarf virus, a garlic strain (OYDV-G) and Leek yellow stripe virus (LYSV). cDNA of Garlic common latent virus (GCLV) was synthesized using oligo-dT and random primers. By these procedures individual garlic virus genomes were isolated and sequenced. The nucleotide sequence analysis associated with serological data reveals the presence of two Potyvirus OYDV-G and LYSV, and GCLV, a Carlavirus, simultaneously infecting garlic plants. Deduced amino acid sequences of the Brazilian isolates were compared with related viruses reported in different geographical regions of the world. The analysis showed closed relations considering the Brazilian isolates of OYDV-G and GCLV, and large divergence considering LYSV isolate. The detection of these virus species was confirmed by specific reactions observed when coat protein genes of the Brazilian isolates were used as probes in dot-blot and Southern blot hybridization assays. In field natural viral re-infection of virus-free garlic was evaluated.

A cultura de ápices caulinares de alho, associada à termoterapia a seco (exposição dos bulbilhos a temperatura de 37°C, por um período de 35 dias) foi essencial para recuperação de plantas livres de vírus das cultivar de alho Amarante. Nestas condições, 70% dos explantes inoculados se desenvolveram in vitro e produziram plantas, das quais 77% não apresentaram partículas virais quando indexadas por ISEM. Isto resulta em um índice de aproveitamento de 54% dos bulbilhos submetidos à termoterapia. O aumento da temperatura na termoterapia para 40°C reduziu a regeneração in vitro para 20%, e 90% dessas plantas estavam livres de vírus, com um índice final de aproveitamento de 18%.

Garlic shoot tip culture associated with dry heat thermotherapy (cloves exposed to 37°C for 35 days) were essential for recovering virus free plants of the cv Amarante. In this condition 70% of the explants developed in vitro and produced plants. A total of 77% of those plants was virus free when indexed by ISEM, which resulted in a final index of 54% of virus free plants from treated cloves. The percentage of regeneration decreased to 20% as the temperature increased up to 40°C. However 90% of those plants were virus free, leading to a final index of 18% virus free plants out of treated cloves.