Since 1992, anthracnose of Andean blackberry (Rubus glaucus) has generated losses as high as 40% for farmers in Colombia. In this study, our goal was to characterize 240 Colletotrichum isolates from Andean blackberry in eight areas of Colombia. These isolates were evaluated according to morphological characteristics, sensitivity to benomyl, pathogenicity, and genetic variability. Identification of the genus Colletotrichum was achieved by using species complex-specific polymerase chain reaction primers. A multilocus phylogeny approach was used to identify isolates to the species level with sequences from the ribosomal internal transcribed spacer region and partial sequences of the actin, β-tubulin 2, calmodulin, chitin synthase 1, glutamine synthetase, and glyceraldehyde-3-phosphate dehydrogenase genes. Most of the isolates were identified as Colletotrichum gloeosporioides sensu lato, were associated with the Castilla ecotype, showed high sensitivity to benomyl, and were highly aggressive. Isolates identified as C. acutatum sensu lato were found mainly on the Thornless ecotype, were highly resistant to benomyl, and showed intermediate aggressiveness. Only three isolates were identified as C. boninense sensu lato. The species identified included C. fructicola, C. kahawae subsp. ciggaro, C. godetiae, C. karstii, C. brassicicola, and undetermined Colletotrichum spp. This study is the first report of these species associated with anthracnose in Andean blackberry.

The strain Purpureocillium sp. UdeA0106 is an antagonist of nematodes, fungi, and garden symphylans from crops with high economic importance in Colombia (Salazar 2013 ; Salazar et al. 2014 ; Cardona et al. 2014 ; Gallego et al. 2014 ) and is being studied to be proposed as new species. It was included on the 1000 fungal genomes project to elucidate its phylogenetic relationships with other fungi. Purpureocillium’s mitogenome has 23,495 bp of circular size. It contains 15 protein-coding genes without duplications (PCGs), corresponding to the 60% of its total length, 23 transfer genes (7.6% tRNA), two of them duplicated (trnR and trnM), and two ribosomal genes (17.6% rRNA) and a GC content of 28.44%. A phylogenetic tree was proposed using their 14 PCGs mitochondrial genes and was compared with other fungi of the Subphylum Pezizomycotina. Phylogenetics relationships showed UdeA0106 to be close to P. chlamydosporia and M. anisopliae forming a cluster with other fungal biocontrol agents and separated the strain of plant pathogenic fungi.

Colombia is recognized as an important agricultural producer of pineapple and flowers. One of the most significant phytosanitary problems of these crops is pathogenic nematodes and it is necessary to find biocontrol alternatives for their management. This study evaluated the effect of Purpureocillium sp., strain UdeA0106, over the number of nematodes. Soil from pineapple and flower crops was collected on expanded polystyrene containers and suspension of the fungi was multiplied in a bioreactor (1x108 conidia/mL), then homogenized and finally applied. The control consisted of the containers with soil and sterile distilled water (SDW) and 4 to 6 repetitions were evaluated on each crop. The number of individuals of each genus on 100g of soil was analyzed using R studio®, Kruskal-Wallis, and van der Waals tests were applied to evaluate significant differences between strain and control (P=0.05). The results showed that the strain did not affect the saprophytic nematodes but decreased the number of Meloidogyne spp., Paratylenchus spp., Helicotylenchus spp., and Tylenchus spp; no biocontrollers had been reported before for the last two genera.

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