Parasexuality in Race 65 Colletotrichum lindemuthianum Isolates

Abstract

Heterokaryosis is the initial step of the parasexual cycle, a process that provides genetic variability in filamentous fungi through the production of heterozygous diploid nuclei. To characterize the parasexual cycle in Colletotrichum lindemuthianum, we evaluated the presence of heterokaryosis, vegetative compatibility reactions, and diploid formation among isolates of Race 65 collected from different Brazilian states. Vegetative compatibility groups were identified among the isolates according to their ability to form heterokaryons. Two heterozygous diploids were selected from compatible heterokaryons, which were characterized by the segregation of the parental auxotrophic markers and by RAPD profiles.

Single nucleus sequencing reveals evidence of inter-nucleus recombination in arbuscular mycorrhizal fungi

“…In fungi, diploid nuclei can undergo recombination either through meiosis, in a sexual cycle, or through aneuploidization, in a parasexual cycle involving nuclear fusion followed by random chromosomal loss. Parasexuality is rare in fungi ( Paccola-Meirelles and Azevedo, 1991 ; Rosada et al, 2010 ; Seervai et al, 2013 ; Bennett, 2015 ), and this process drives recombination via mitotic events (as opposed to meiosis in a sexual cycle). It also requires the stable division of diploid nuclei for many generations to produce recombination through mitosis ( Clutterbuck, 1996 ).…”

Genome‐wide association study of resistance to anthracnose and angular leaf spot in Brazilian Mesoamerican and Andean common bean cultivars

“…On the other hand, races 65 and 73 are the most frequent and widespread races in Brazil (Thomazella, Gonçalves‐Vidigal, Vidigal Filho, Nunes, & Vida, 2002a; Gonçalves‐Vidigal, Thomazella, Vidigal Filho, Kvitschal, & Elias, 2008; Pereira, Ishikawa, Pinto, & Souza, 2010; Damasceno e Silva, Souza, & Ishikawa, 2007; Xavier et al., 2018). Previous studies revealed that race 65 presented high variability in several states of Brazil (Coêlho et al., 2016; Ishikawa, Souza, & Davide, 2008; Rosada et al., 2010; Santos, Antunes, Rey, & Rossetto, 2008; Thomazella et al., 2002b). Race 9 has been reported on the African and American continents, especially in countries such as Brazil, Colombia, Peru, Mexico, Guatemala, Honduras, Costa Rica, the Dominican Republic, and Argentina (Balardin et al., 1997; Mahuku & Riascos, 2004; Nunes et al., 2013; Pastor‐Corrales et al., 1995; Souza et al., 2016).…”

PacCl, a pH-responsive transcriptional regulator, is essential in the pathogenicity of Colletotrichum lindemuthianum, a causal agent of anthracnose in bean plants

“…However, due to the large genetic variability of C. lindemuthianum, the breakdown of resistance prevents the use of cultivars for long periods of time, thus hindering the establishment of a permanent solution to the disease (Rodriguez-Guera et al 2003;Ansari et al 2004;Mahuku and Riascos 2004;Barcellos et al 2011). The large genetic and pathogenic variability found in Colletotrichum species has been extensively studied, and it can be partially explained by recombinant events and mutations caused by the presence of transposons (Casela and Frederiksen 1994;Santos et al 2012), and by the presence of anastomoses among conidia (Roca et al 2003;Castro-Prado et al 2007;Rosada et al 2010;Franco et al 2011).…”