ABSTRACT. Lasiodiplodia theobromae is a plant pathogen with a worldwide distribution, with low host specificity, causing stem cankers, dieback diseases, and fruit rot in several species of plants. In coconut, this pathogen is reported as the etiological agent of "coconut leaf blight" (CLB) disease, causing several losses in fruit production. The CLB is an important disease for this crop in Brazil. In our study, we used a phylogeographic approach through the molecular characterization of the translation elongation factor 1-α (TEF1-α) to elucidate the pathogen distribution in Brazil and other countries, besides, search information about diversity sources of this pathogen in coconut palm tree at Brazilian northern, northeast, and southeast. We found that L. theobromae diversity is within populations (locations), and populations that are located closest to the center of the tropical zone have more variability as Central Africa, Brazilian Southeast, and Northeast. The widespread distribution could be in part related with long-distance dispersal via global trade of plants and plant products. The entrance route of L. theobromae in Brazil probably occurred from Africa route and not occurred once. In Brazil, the diversity of this pathogen in coconut tree could be linked to two agents of selection: high host diversity (in Northeast) and distinct management measures adopted in Southeast. These different sources of selection, mainly the mutations, could be one of the reasons that we found distinct reactions to "coconut leaf blight" chemical control in these regions.

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Equine herpesvirus (EHV) commonly affects horses causing neurologic and respiratory symptoms beside spontaneous abortions, meaning huge economic losses for equine industry worldwide. In foals the virus can facilitate secondary infections by Rhodococcus equi, important in morbidity and mortality in equines. A total of five genotypes of EHV were previously described in Brazil including EHV-1, EHV-2, EHV-3, EHV-4 and EHV-5. EHV-2 genotype had only been previously described in Brazil in asymptomatic animals. We report the dead of 11 foals in Middle-west region of Brazil showing respiratory and neurological symptoms, as well as several abortions in mares from the same farm. Laboratory exams revealed neutrophilia leukocytosis. Necroscopic and histopathologic findings were suppurative bronchopneumonia and ulcerative enteritis. Molecular assays point to the absence of the bacteria Rhodococcus equi and other EHV. The presence of EHV-2 DNA was confirmed by sequencing in serum sample from one foal. This is the first confirmed outbreak of EHV-2 causing disease in Brazilian horses with confirmed presence of the virus. EHV-2 has been neglected and could be highlight the important role of EHV-2 in equine respiratory disease and spontaneous abortions in equid in Brazil. Author SummaryEquid herpesvirus type 2 (EHV-2), a gammaherpesvirus, has been neglected and can cause respiratory infection, abortion and in extreme cases neurologic symptoms and dead.Outbreaks of EHV-2 never was described in Brazil and can be critical to losses in equid industry. Our report provides evidence for a direct link between the EHV-2 strain and the outbreak in foals. We proved the clinical, histopathological and phylogenetic analysis of segment of EHV-2 polymerase.In summary, our study confirm that Gammaherpesvirus 2 is circulating in Brazil and the EHV-2 is a cause of the first outbreak in foals showing the important role of EHV-2 in equid respiratory disease.

ABSTRACT. Northern leaf blight (NLB), caused by Exserohilum turcicum, is one of the main foliar diseases that affect popcorn culture. Farmers use many control measures to minimize damage caused by this disease, among which, the use of cultivars with genetic resistance is the most effective and economical. The aim of this study was to investigate genetic variability influencing resistance to NLB in 25 popcorn maize lines grown under high and low phosphorus conditions in relation to foliar fungal disease caused by E. turcicum. We evaluated the disease incidence and severity, by analysis of variance and cluster test (Scott-Knott). There was sufficient genetic variability between strains for resistance traits. Genotypic variance was higher than environmental variance, and had more discriminatory power. We conclude that new progenies could be selected for the establishment of future populations. P-7, P-9, L-59, L-71, and L-76 progenies possess promising characteristics that simultaneously reduce the severity and the incidence of NLB in popcorn plants.