ITS-rDNA phylogeny of Colletotrichum spp. causal agent of apple Glomerella leaf spot

Abstract

Several diseases have affected apple production, among them there is Glomerella leaf spot (GLS) caused by Colletotrichum spp. The first report of this disease in apple was in plants nearby citrus orchards in São Paulo State, Brazil. The origin of this disease is still not clear, and studies based on the molecular phylogeny could relate the organisms evolutionarily and characterize possible mechanisms of divergent evolution. The amplification of 5.8S-ITS (Internal Transcribed Spacer) of rDNA of 51 pathogenic Colletotrichum spp. isolates from apples, pineapple guava and citrus produced one fragment of approximately 600 bases pairs (bp) for all the isolates analyzed. The amplified fragments were cleaved with restriction enzymes, and fragments from 90 to 500bp were obtained. The sequencing of this region allowed the generation of a phylogenetic tree, regardless of their hosts, and 5 isolated groups were obtained. From the "in silico" comparison, it was possible to verify a variation from 93 to 100% of similarity between the sequences studied and the Genbank data base. The causal agent of GLS is nearly related (clustered) to isolates of pineapple guava and to the citrus isolates used as control.

The Colletotrichum acutatum species complex

“…Additionally, the ITS sequences of isolates DPI from Citrus aurantifolia in Florida, USA (FN566877, Ramos et al 2006 ) and c2 from Citrus sp. in Brazil (EU008878, Giaretta et al 2010 ) match that of CBS 144.14 with 100 % identity. Probable C. limetticola strains are also included in Guerber et al ( 2003 ) as mtDNA RFLP haplotype J3; the GAPDH sequences of two Key lime strains (MD33, MD15) are almost identical to that of CBS 114.14 .…”

“…The closest matches with the ITS sequence with 100 % identity were FN566877 from isolate DPI from Citrus aurantifolia in Florida, USA ( Ramos et al 2006 ) and isolate c2 from Citrus sp. in Brazil ( Giaretta et al 2010 ).…”

One stop shop: backbones trees for important phytopathogenic genera: I (2014)

“…Colletotrichum species commonly cause anthracnose resulting in sunken necrotic lesions on leaves, stems, flowers and fruits of numerous hosts, including important crops (Lenne 2002;Waller et al 2002;Agrios 2005;Cai et al 2009;Than et al 2008;Peng et al 2012;Doyle et al 2013). It is therefore important to plant health disease practitioners, quarantine personnel and plant breeders to know what species infect which crops (Huang et al 2013b;Lima et al 2013;Giaretta et al 2010;Sangeetha and Rawal 2010;Liu et al 2009a;Akinbode and Ikotun 2008;Adegbite and Amusa 2008;Peres et al 2002). Therefore, having a rigid and stable taxonomy for the identification of Colletotrichum species is a significant practical concern (Shenoy et al 2007).…”

Unraveling Colletotrichum species associated with Glomerella leaf spot of apple

“…The taxonomy of Colletotrichum has evolved dramatically in recent years, as relationships have been re-examined using novel approaches, such as studies combining multilocus phylogeny, morphological characterization and pathogenicity tests (Damm et al 2012a, b;Weir et al 2012). As consequence, those species affecting apple trees formerly identified as C. gloeosporioides and C. acutatum (González et al 2006;Giaretta et al 2010) were reclassified into new species (Damm et al 2012a, b;Weir et al 2012). As of now Colletotrichum fructicola Prihastuti, Cai & Hyde (Velho et al 2015;Rockenbach et al 2016) and Colletotrichum karstii Yang, Liu, Hyde & Cai (Velho et al 2014) have been reported associated with GLS in Southern Brazil.…”