Bacterial spot, caused by Xanthomonas spp., is one of the major diseases of pepper in Brazil, causing considerable losses to crop productivity. The efficient management of the disease is hampered by the high variability of the causal agents. In Brazil, there is no knowledge of which species of Xanthomonas occurs on pepper. In this study, 59 strains of Xanthomonas spp. isolated from different pepper-producing regions of Brazil were characterized by biochemical and molecular techniques. Results showed the prevalence of X. euvesicatoria as the causal agent of bacterial spot on pepper in Brazil.

RESUMOÉ crescente o número de pacientes submetidos à cirurgia bariátrica para tratamento da obesidade mórbida; devido a isso, estão reaparecendo deficiências nutricionais com as quais muitos médicos já não estão familiarizados. No pós-operatório, podem ocorrer vários distúrbios nutricionais, sendo um deles a deficiência de tiamina (beribéri). A deficiência de tiamina e/ou vitamina B12 pode corresponder a 40% dos casos de neuropatia após a cirurgia bariátrica. Serão descritos dois pacientes com a clínica de neuropatia periférica e síndrome de Wernicke-Korsakoff. Alguns meses após a cirurgia, eles apresentaram prostração, depressão, confusão mental e nistagmo, associados a dor e parestesia dos membros (principalmente inferiores). Com a hipótese diagnóstica de beribéri, foi iniciado o tratamento com tiamina. Um dos pacientes apresentou melhora completa do quadro neurológico, porém o outro permaneceu com déficit motor, sendo aquele em que decorreu o maior tempo entre o aparecimento dos sintomas e o início do tratamento. Estes casos servem para nos alertar sobre a importância da vigilância nutricional após a cirurgia bariátrica. The number of patients submitted to bariatric surgery to treat morbid obesity is increasing, therefore, some nutritional deficiencies, with which many physicians are no longer familiarized, are reappearing. Postoperatively, many nutritional disorders may occur, one of them is thiamine deficiency (beriberi). The thiamine and/or vitamin B12 deficiency can correspond to 40% of the neuropathy cases after bariatric surgery. Two patients with the clinic of peripheral neuropathy and Wernicke-Korsakoff syndrome will be reported. Some months after the surgery, they presented prostration, depression, mental confusion and nystagmus, associated with pain and paresthesia in limbs (especially lower limbs). With the diagnostic hypothesis of beriberi, the treatment with thiamine started. One of the patients presented complete improvement of the neurological symptoms, however the other one remained with motor deficiency, exactly the one who spent a longer period of time between the symptoms appearance and the treatment beginning. These cases serve to alert us about the importance of nutritional vigilance after bariatric surgery. (Arq Bras Endocrinol Metab 2006;50/3:564-568)

Alternative hosts are an important way of phytopathogenic bacteria survival between crop seasons, constituting a source of inoculum for the following crops. Bacterial wilt, caused by Curtobacterium flaccumfaciens pv. flaccumfaciens (Cff), is one of the most important diseases for common bean, and little information is available about the host range of the bacterium. In this study, we assessed possible alternative hosts for Cff, especially those cultivated during winter, in rotation systems with common bean. Plants of barley, black oat, canola, radish, ryegrass, wheat and white oat, were assessed under field and greenhouse conditions. Cff colonized epiphytically all plant species and endophytically black oat, ryegrass, wheat and white oat plants assessed in the greenhouse assays. Under field conditions, Cff colonized all plant species by except radish. All bacterial strains re-isolated from the plants were pathogenic to common bean and identified as Cff by PCR with specific primers. Based on our results, the cultivation of bean crop in succession with barley, black oat, canola, ryegrass, wheat and white oat should not be recommended, mainly in areas with a history of bacterial wilt occurrence. In these cases, the better option for crop rotation during the winter is radish, a non-alternative host for Cff.

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Bacterial spot, caused by Xanthomonas spp., is one of the major bacterial diseases in pepper (Capsicum annuum L.). The infection results in reduced crop yield, particularly during periods of high rainfall and temperature, due to the low efficiency of chemical control with copper bactericides. This study evaluated the copper and zinc sulfate sensitivity of 59 pathogenic strains of Xanthomonas euvesicatoria isolated from pepper plants produced in various regions throughout Brazil. Both the respective sulfates and a mixture thereof was evaluated at 50, 100, 200 and 400 μg.mL -1 . All the evaluated strains were found to be resistant to zinc sulfate (100 μg.mL -1 ) and 86.4% were resistant to copper sulfate (200 μg.mL -1 ). The mixture of copper (200 μg.mL -1 ) and zinc (200 μg.mL -1 ) sulfates inhibited the growth of all strains of X. euvesicatoria.To our knowledge this is the first study to report the resistance of X. euvesicatoria strains from pepper plants to copper and zinc sulfates in Brazil.

The objective of this study was to evaluate the efficacy of the active ingredient abamectin, either in isolation or in combination with fungicides and insecticides formulated for the industrial seed treatment, on the population of Meloidogyne javanica, tested under greenhouse and in vitro conditions. In both tests, the combination of the following treatments was assessed: abamectin; thiamethoxam; fludioxonil + metalaxyl-M + thiabendazole. Water was used as control for the in vitro assay, whereas under greenhouse conditions, controls were inoculated and not inoculated with M. javanica. The tests were conducted in a completely randomized design with six (in vitro) and ten (greenhouse) replicates. For in vitro studies the effect on hatching, motility, and mortality of juveniles of M. javanica was evaluated. Under greenhouse conditions, the soybean 'BRS 133' seeds were treated, and at 15, 30, and 60 days after inoculation (DAI) with M. javanica, plant measurements were recorded. The penetration of second stage juveniles (J2) was also evaluated at 15 DAI. At 30 DAI, galls, egg masses, nematodes/g of root, and final population were evaluated. At 60 DAI, the final population of nematodes in the roots was quantified. The treatments containing abamectin were the most effective in diminishing the hatching of juveniles. All treatments had an effect on nematode motility when compared to the control, and in the treatment containing only abamectin, total juvenile mortality was observed. In greenhouse conditions, at 15 DAI, the treated soybean plants had the highest root mass and shoot length, differing statistically from the inoculated control. All treatments reduced the number of nematodes per gram of root, differing from the control. At 30 DAI, treatment efficiency was observed in reducing the final population of M. javanica, particularly the treatments using abamectin, and abamectin + thiamethoxam + fludioxonil + metalaxyl-M + thiabendazole. However, at 60 DAI, the effect of the treatments on the population of M. javanica did not persist. Key words: Hatching. Mortality. Motility. Nematicide. Root-knot nematode. ResumoO objetivo do trabalho foi avaliar a eficiência do ingrediente ativo abamectina, isolado ou em combinação com fungicidas e inseticidas formulados para o tratamento industrial de sementes, sobre a população de Meloidogyne javanica, in vitro e em casa de vegetação. Em ambos os ensaios, avaliou-se a combinação dos tratamentos: abamectina; thiamethoxam; fludioxonil + metalaxil-m + tiabendazol. Como controle utilizou-se água para o ensaio in vitro, e testemunhas inoculada e não inoculada com M. javanica, em casa de vegetação. Os ensaios foram realizados em delineamento inteiramente casualizado

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Orange rust caused by the fungus Puccinia kuehnii greatly affects sugarcane and causes millions of tons of losses in production. This condition was first reported in Brazil at the end of 2009. The disease is currently present in most of the countries that produce this crop. The aim of this research was to develop risk maps of P. kuehnii infection using temperature and relative humidity data, provided by 389 automatic weather stations throughout the country. A spatial distribution analysis was carried out to assess the number of daily hours of favorable conditions for spore germination in each region. In the central-south region, where the main sugarcane producing states are concentrated, two distinct periods were observed during the three years studied. Higher favorability occurred from October to April, and lower favorability occurred from May to September. The opposite relation was observed on the coast of the north-eastern region, where conditions were more favorable to the disease from May to September. The validation data were confirmed by the results of Pearson's correlation between sugarcane orange rust infection under field conditions and the proposed maps. In conclusion, risk maps obtained using data from automatic weather stations could contribute to the monitoring of the risk of infection by sugarcane orange rust.