Anthracnose, caused by the hemiotrophic fungus Colletotrichum sublineolum, is one of the most important diseases affecting sorghum production worldwide. The main goal of this study was to select saprobe fungi from the semi‐arid north‐east of Brazil that could increase sorghum resistance to anthracnose and investigate this increased resistance at both physiological and biochemical levels. Plants were sprayed with Curvularia inaequalis, Gonytrichum macroladum, Memnoniella levispora, Pithomyces chartarum, Periconia hispidula, Phaeoisaria clematidia, Dictyochaeta heteroderae, Sarcopodium circinatum, Periconia byssoides, Moorella speciosa, Stachybotrys chartarum, Pseudobotrytis terrestres, Memnoniella echinata, Stachybotrys globosa and Gonytrichum clamydosporium 24 h before inoculation with C. sublineolum. Plants sprayed with water served as the control treatment. The area under the anthracnose progress curve was significantly reduced in comparison with the control treatment only for plants sprayed with C. inaequalis. Therefore, C. inaequalis was selected for physiological and biochemical evaluations. The peroxidases, chitinases and β‐1,3‐glucanases activities were significantly higher for plants sprayed with C. inaequalis and inoculated with C. sublineolum than for plants not sprayed with C. inaequalis and inoculated with C. sublineolum. There was no apparent decrease in the values of net carbon assimilation rate, stomatal conductance to water vapour or transpiration rate for plants sprayed with C. inaequalis and infected by C. sublineolum in comparison with plants not sprayed with C. inaequalis and infected by C. sublineolum. In conclusion, sorghum resistance against C. sublineolum infection was greatly potentiated by C. inaequalis without any apparent change in the photosynthetic capacity of the infected plants.

Pachira glabra (Malvaceae) occurs naturally in Brazil's Atlantic Forest and is used to recover degraded areas of permanent preservation. Symptoms of leaf spot caused by Diaporthe spp. have been observed in P. glabra saplings in a Brazilian forest nursery. The aim of this study was to identify the fungal species employing morphological characteristics, pathogenicity tests, and DNA sequence comparisons for the internal transcribed spacer region (ITS), β-tubulin (TUB), translation elongation factor 1-α (TEF1), and calmodulin (CAL) gene regions. A novel species was identified and described, named here as Diaporthe pachirae. Furthermore, this is the first report of a species belonging to Diaporthe on P. glabra in Brazil. The current study revealed that documentation of new fungi is a relevant forerunner to any research with natural forests.

Summary The fungus Pseudobeltrania cedrelae, the type species of the genus, is the causal agent of an important leaf spot in seedlings and adult plant of cedar (Cedrela fissilis). Due to the contradictory phylogenetic position of the genus Pseudobeltrania, epitypification of P. cedrelae was carried out based on a culture obtained from the same locality and host of the original type. Samples were collected, and 10 isolates of P. cedrelae associated with lesions on cedar leaflets were obtained. For morphological characterization, conidia, conidiophores, conidiogeneous cells, conidiogeneous loci and basal cells were taken both from the fungus obtained from leaf lesions and from that obtained in slide culture. Mycelial growth rates and sporulation were evaluated in six different culture media. For molecular phylogeny, maximum parsimony analyses were performed from the ITS and 28S sequences of the isolates. Both the morphological characteristics of the fungal structures obtained from symptomatic leaves and the slide culture technique presented variations. In foliar lesions, isolates presented the same morphological characteristics as the type material. Mycelial growth rate and sporulation of P. cedrelae were greatest on malt extract agar and V8 juice agar. Pseudobeltrania cedrelae was pathogenic when inoculated into healthy cedar plants. According to the phylogenetic tree, isolates grouped in the same clade, but in a distinct clade of Pseudobeltrania ocoteae. The results suggested that P. ocoteae belongs to the genus Hemibeltrania. This paper presents new information on P. cedrelae that contributes to clarifying the phylogeny of the Beltraniaceae.

Bacillus subtilis is a spore-forming bacterium and an important food contaminant. The aim of this study was to analyze the ability of B. subtilis spores to survive under conditions of low pH and high temperature. The package was purchased at a local supermarket, in Uberaba, Minas Gerais. A sample was collected, diluted and plated on Brain-Heart-Infusion agar (BHI). After incubation, suspected colonies of B. subtilis were transferred to BHI agar. Cell morphology, the presence of spores and Gram stain were examined, and the isolate was identified by 16S rRNA gene sequencing . The microscope evaluation indicated the presence of spores. The thermal tolerance of the spores was evaluated by the addition of 3x109spores/mL in test tubes containing peptone water. Heat treatments were carried out at 80 and 90°C at different incubation times (0, 10, 20, 30, 40, 50 and 60 min). After heating, the tubes were cooled and the number of viable spores was determined in BHI Agar. For the analysis of spore survival, D and Z values were calculated. Tolerance to acid conditions was evaluated using BHI broth with different pH values. After incubation, the bacterial concentration was determined by determining viable cell count on BHI Agar medium. The vegetative cells were transferred to the BHI broth and the pH was adjusted to different values (3, 4 or 5). Sampling were taken 8, 12 and 24 h after incubation. The samples were serially diluted in peptone water and spread in BHI Agar to determine the viable cell count . The 16S rRNA gene sequencing indicated high similarity (99.99%) with B. subtilis. D values were 17.01 min at 80°C and 13.42 min at 90°C. The Z-value was 97.13°C. B. subtilis was not able to grow at pH 3 and pH 4, but its survival was confirmed after the growth of colonies on BHI agar. At pH 5, B. subtilis grew after 24 h and the final pH changed to 7. Our results suggest that the spores of B. subtilis isolated from fruit juice-added soy beverage are tolerant to low pH and high temperature.

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