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Aims: Fungal diseases are among the main factors limiting high yields of soybean crop. Colletotrichum isolates from soybean plants with anthracnose symptoms were studied from different regions and time periods in Brazil using molecular, morphological and pathogenic analyses., Methods and Results: Bayesian phylogenetic inference of GAPDH, HIS3 and ITS-5.8S rDNA sequences, the morphologies of colony and conidia, and inoculation tests on seeds and seedlings were performed. All isolates clustered only with Colletotrichum truncatum species in three well-separated clusters. Intraspecific genetic diversity revealed 27 distinct haplotypes in 51 fungal isolates; some of which were identical to C. truncatum sequences from other regions around the world, while others were related to alternative hosts. Conidia were falcate, hyaline, unicellular and aseptate, formed in acervuli, with variable dimensions. Despite being pathogenic to seedlings by both inoculation methods, variation was observed in the aggressiveness of the tested isolates, which was not correlated with genetic variation., Conclusion: The identification of C. truncatum in the sampled isolates was evidenced as being the only causal agent of soybean anthracnose in Brazil until 2007, with relevant genetic, morphological and pathogenic variability as well as a broad geographical origin. The wide distribution of the predominant C. truncatum haplotype indicated the existence of a highly efficient mechanism of pathogen dispersal over long distances, reinforcing the role of seeds as the primary source of disease inoculum., Significance and Impact of the Study: The characterization and distribution of Colletotrichum species in soybean-producing regions in Brazil is fundamental for understanding the disease epidemiology and for ensuring effective control strategies against anthracnose., (© 2016 The Society for Applied Microbiology.)

Bananas are one of the most consumed fruits worldwide, but are affected by many pests and diseases. One of the most devastating diseases is Fusarium wilt, caused by Fusarium oxysporum f. sp cubense (Foc). Recently, Fusarium tropical race 4 (Foc TR4) has been causing irreparable damage, especially in Asia and Africa where it has devastated entire plantations, including areas with Cavendish, which is known to be resistant to Foc race 1. Although this race is not yet present in Brazil, results obtained by Embrapa in partnership with the University of Wageningen, The Netherlands, indicate that 100% of the cultivars used by Brazilian growers are susceptible to Foc TR 4. In our study, 276 banana accessions were screened with sequence characterized amplified region (SCAR) markers that have been linked to the resistance of Foc TR 4. Two SCAR primers were tested and the results revealed that SCAR ScaU1001 was efficient at discriminating accessions with possible resistance in 36.6% of the evaluated accessions. This is the first attempt to develop a thematic collection of possible Foc TR 4 resistant banana accessions in Brazil, which could be tested in Asian or African countries to validate marker-assisted selection (MAS), and for use in the preventive breeding of the crop to safeguard our banana plantations against Foc TR 4. We believe that this is an important step towards the prevention of this devastating disease, especially considering that our banana plantations are at risk.