Pitch canker is one of the most important diseases of pine trees worldwide, including South America. The causal agent of this disease is Fusarium circinatum, a member of the Gibberella fujikuroi complex (GFC). In South America, the species is reported from Colombia, Uruguay and Chile, but is considered a quarantine organism in Brazil. In this study we characterized isolates obtained from symptomatic pine seedlings intercepted in a nursery in Santa Catarina State using phylogenetic analyses, crossings and morphological markers. The Brazilian isolates grouped with reference material in an unique clade and formed fertile perithecia when crossed with reference tester strains. The detailed characterization given here and the availability of tester strains will allow for reliable identification and support monitoring of this important plant pathogen.

Brazil is the world’s biggest producer of sugarcane (Saccharum spp. hybrids). Pokkah boeng is an important fungal disease in this crop caused by members of the Fusarium fujikuroi species complex (FFSC) and characterized by deformation of the aerial part of the plant and stem rot. While the occurrence of symptoms has been reported in plantations in Brazil, no official reports of the disease exist. In this study, species of the FFSC were identified that are associated with sugarcane plants with symptoms of pokkah boeng in Brazil. This was achieved using two‐loci molecular phylogeny, sexual compatibility and analysis of morphological markers. The ability of strains to cause disease in plants of sugarcane, maize, sorghum and millet was also evaluated. The 39 isolates studied were identified as F. sacchari, F. proliferatum and another, still unknown, phylogenetic lineage that is sister to F. andiyazi. Crossing field isolates of F. sacchari and F. proliferatum with their respective tester strains produced fertile perithecia and viable ascospores. All three species induced symptoms of pokkah boeng on inoculated sugarcane plants and caused stem rot in maize, sorghum and millet. Symptoms on sugarcane are chlorosis and necrosis of leaves, punctured lesions, twisted leaves, reduction of the total leaf area, death of the top of the plant and stalk rot. The findings confirmed the aetiology of the disease in Brazil, generated basic knowledge for the development of strategies for diagnosis and monitoring of the disease and support breeding programmes for selecting resistant germplasm.

The taxonomy of the genus Colletotrichum has undergone various changes. These alterations arise from the use of modern molecular tools. Currently, Colletotrichum species are grouped into complexes. Species of Colletotrichum associated with diseases in lima bean have been investigated very little. In Brazil, anthracnose in lima bean has often been associated with Colletotrichum truncatum, but only morphological characteristics have been used for identification purposes. In this study, samples of lima bean with symptoms of spots on the leaves and pods have been collected in Piauí and Alagoas states. Comparisons of morphological characteristics revealed nine isolates with cylindrical or curved conidia. The ITS region and partial sequences of GAPDH, β-tubulin and Actin regions were amplified by PCR, sequenced and submitted to multilocus phylogenetic analysis. The isolates analyzed grouped with reference specimens from Colletotrichum truncatum, C. cliviae and C. fructicola. All isolates were pathogenic to 25-day-old lima bean seedlings. Therefore, this work confirms the pathogenicity of C. truncatum to lima bean and for the first time records the occurrence of C. cliviae and C. fructicola as pathogens of this host in Brazil.

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