Identification of Races of Colletotrichum lindemuthianum with the Aid of PCR-Based Molecular Markers

Abstract

Inoculation of a common bean differential series is the usual method for identification of races of Colletotrichum lindemuthianum. This procedure is extremely useful for phytopathological as well as breeding purposes, but it requires strict control of the number of spores and incubation conditions. Furthermore, this method may result in misclassifications of isolates because of the subjectivity of symptom evaluation. We propose the use of DNA-based molecular markers as an auxiliary tool to aid the classification of races of C. lindemuthianum. Specific DNA bands were identified for races 73, 65, and 64 by polymerase chain reaction (PCR) amplification of bulked DNA samples from isolates of these three races with random primers. The presence of these bands was checked on four isolates previously classified by inoculation on a differential series as belonging to races 23, 72, 79, and 585. The molecular procedure showed that two of these isolates had been misclassified, confirming the high potential of the proposed procedure to aid the identification of races of C. lindemuthianum. Amplification products obtained with 44 different primers also allowed the determination of the genetic distances among isolates from races 73, 65, and 64. These data were used to cluster the isolates into three groups that coincide with the ones obtained by inoculation.

Genetic diversity of the bacterial wilt pathogen Ralstonia solanacearum using a RAPD marker

“…RAPD markers were used because they have the potential to detect polymorphism in the entire genome as compared to other techniques [23]. RAPD markers have been used for strain differentiation [24], identification and other genetic analysis for several bacterial genera during the last two decades [23,[25][26][27][28]. Taken together, the present study was undertaken to assess the potentiality of RAPD as a marker for analysing the diversity of R. solanacearum collected from some fields of some selected locations.…”

Characterization of Colletotrichum lindemuthianum Isolates from the State of Minas Gerais, Brazil

“…In order to determine whether the pattern of infection of the differential cultivars by C. lindemuthianum isolates is a general pattern observed in other studies, a comparison was made of the infection patterns of all races reported in Minas Gerais state in the last 10 years (Fig. 1b; Rava et al., 1994; Vilarinhos et al., 1995; Alzate‐Marin et al., 1997; Mesquita et al., 1998; Sartorato, 2002; Talamini et al., 2002, 2004). These compiled results indicate that the cultivars most frequently found to be susceptible in other studies are Mexico 222, Michelite, MDRK, Perry Marrow, Widusa, Cornell 29242, Widusa and Kaboon.…”

“…The genetic diversity of C. lindemuthianum has been investigated using random amplified polymorphic DNA (RAPD) marker analysis (Balardin et al., 1997; Sicard et al., 1997; González et al., 1998; Mesquita et al., 1998; Thomazella et al., 2002; Mahuku and Riascos, 2004), amplified fragment length polymorphism (González et al., 1998) and random amplified microsatellites (RAMs) (Mahuku and Riascos, 2004). These studies have revealed that C. lindemuthianum is a highly variable pathogen that maintains high levels of genetic diversity.…”

Genotypic diversity in a localized population of Ralstonia solanacearum as revealed by random amplified polymorphic DNA markers

“…RAPD was used as it has the potential to detect polymorphism in the entire genome as compared to other techniques (Hilton and Penn 1998). RAPD markers have been used for strain differentiation (Mesquita et al 1998), identification and other genetic analysis for several bacterial genera (Akopyanz et al 1992;Mazurier et al 1992;Parent et al 1996;Hilton and Penn 1998;Khoodoo et al 2002).…”