A multiyear survey of >200 wheat fields in Paraná (PR) and Rio Grande do Sul (RS) states was conducted to assess the extent and distribution of Fusarium graminearum species complex (FGSC) diversity in the southern Brazilian wheat agroecosystem. Five species and three trichothecene genotypes were found among 671 FGSC isolates from Fusarium head blight (FHB)-infected wheat heads: F. graminearum (83%) of the 15-acetyldeoxynivalenol (15-ADON) genotype, F. meridionale (12.8%) and F. asiaticum (0.4%) of the nivalenol (NIV) genotype, and F. cortaderiae (2.5%) and F. austroamericanum (0.9%) with either the NIV or the 3-ADON genotype. Regional differences in FGSC composition were observed, with F. meridionale and the NIV type being significantly (P<0.001) more prevalent in PR (>28%) than in RS (≤9%). Within RS, F. graminearum was overrepresented in fields below 600 m in elevation and in fields with higher levels of FHB incidence (P<0.05). Species composition was not significantly influenced by previous crop or the stage of grain development at sampling. Habitat-specific differences in FGSC composition were evaluated in three fields by characterizing a total of 189 isolates collected from corn stubble, air above the wheat canopy, and symptomatic wheat kernels. Significant differences in FGSC composition were observed among these habitats (P<0.001). Most strikingly, F. meridionale and F. cortaderiae of the NIV genotype accounted for the vast majority (>96%) of isolates from corn stubble, whereas F. graminearum with the 15-ADON genotype was dominant (>84%) among isolates from diseased wheat kernels. Potential differences in pathogenic fitness on wheat were also suggested by a greenhouse competitiveness assay in which F. graminearum was recovered at much higher frequency (>90%) than F. meridionale from four wheat varieties inoculated with an equal mixture of F. graminearum and F. meridionale isolates. Taken together, the data presented here suggest that FGSC composition and, consequently, the trichothecene contamination in wheat grown in southern Brazil is influenced by host adaptation and pathogenic fitness. Evidence that F. meridionale and F. cortaderiae with the NIV genotype are regionally significant contributors to FHB may have significant implications for food safety and the economics of cereal production.

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Maize (Zea mays) fields from a tropical central (Goiás state) and a subtropical south region (Paraná state) of Brazil were surveyed for Cercospora species causing gray leaf spot (GLS), a foliar fungal disease of increasing concern to growers of the country. Single spore isolates were obtained from maize leaves showing GLS symptoms and species-specific primers were used for species identification. In addition, a phylogeny of isolates representative of each species was conducted based on partial DNA sequencing of the EF1-α, CAL, and HIS genes, and ITS-5.8S rDNA region. In the regional collections, Cercospora zeina was the dominant species in Goiás (68/75 isolates) and Paraná (73/75 isolates), followed by C. zeae-maydis and C. sorghi var. maydis, respectively. In three field collections of both states, C. zeina was the sole species found. The phylogenetic characterization of isolates representing C. zeina (n=18), C. zeae-maydis (n=6), and C. sorghi var. maydis (n=2) confirmed the identity of the species and grouped them in well-supported clades.

RESUMOA antracnose, causada pelo fungo Colletotrichum gloeosporioides, é a doença de pós-colheita mais importante da passicultura. Este trabalho avaliou o potencial de Agaricus blazei e Lentinula edodes nas concentrações de 20, 40 e 60% (v/v) e do acibenzolar-S-metil (ASM) a 75 e 150 mg/L, aplicados isoladamente ou de forma combinada, na proteção de frutos de maracujá-azedo contra antracnose. Os frutos foram tratados (imersão, aspersão ou incorporados em cobertura de fécula de mandioca) e após 36h ou 72h, inoculados com o fungo. A avaliação da doença foi feita pela medida da área necrosada nos frutos aos 4, 8 e 12 dias após a inoculação (dai) nos ensaios I e II e aos 3, 6 e 9 dai nos ensaios III, IV e V. Aos quatro dias após a inoculação, o tratamento com A. blazei associado à fécula de mandioca 3% apresentou uma redução significativa da área necrosada comparado ao controle (p = 0,035). O L. edodes e ASM não reduziram a doença em nenhuma das concentrações e/ou épocas de avaliações realizadas. Quando os compostos foram aplicados de forma combinada nos frutos e estes não foram lavados antes da inoculação, houve uma redução significativa da área necrosada aos seis dias após a inoculação (p = 0,03). Entretanto, quando os frutos foram tratados, lavados e inoculados com o fungo não houve redução da doença em nenhuma das épocas avaliadas, mostrando que o modo de ação dos compostos utilizados, possivelmente, ocorre por um efeito protetor/residual atrelado a um efeito inibitório sobre C. gloeosporioides. Palavras-chave: Colletotrichum gloeosporioides, fécula de mandioca, pós-colheita, proteção. ABSTRACT Application of suspensions of Agaricus blazei, Lentinula edodes and acibenzolar-S-methyl for the reduction of anthracnose on passion fruitAnthracnose caused by Colletotrichum gloeosporioides is one of the most important diseases of passion fruit. This study evaluated the potential of Agaricus blazei and Lentinula edodes at concentrations of 20, 40 and 60% (v/v) and acibenzolar-S-methyl (ASM) at 75 and 150 mg/L, applied alone or in combination, for protecting passion fruit against anthracnose. The fruits were treated (immersion, sprayings or in coverage of cassava starch) and after 36h or 72h were inoculated with the fungus. Disease assessment was done by measuring the necrotic area in the fruits at 4, 8 and 12 dai (days after inoculation) in assays I and II and 3, 6 and 9 dai in assays III, IV and V. At three days after inoculation, the treatment with A. blazei associated with cassava starch 3% showed a significant reduction of necrotic area compared to the control (p = 0.035). The L. edodes and ASM treatments did not reduce the disease in any concentration and/or periods of the evaluations. When the compounds were applied in combination and the fruits were not washed before inoculation, there was a significant reduction of necrotic area six days after inoculation (p = 0.03). However, when fruits were treated, washed and inoculated with the fungus there was no reduction of disease in any of the periods evaluated, showing ...