RAPD-Based Inter- and Intravarietal Classification of Fungi of the Gaeumannomyces-Phialophora Complex

Abstract

The suitability of randomly amplified polymorphic DNAs (RAPD) for differentiation at the varietal and intravarietal level was tested on several hundred isolates of the gaeumannomyces‐Phialophora (G‐P) complex from different geographic locations and host plants. Amplification products obtained using two decamer primers allowed differentiation between gaeumannomyces graminis and gaeumannomyces cylindrosporus and between the three varieties of gaeumannomyces graminis, as well as further division at the intravarietal level. Thus, isolates of the causal agent of take‐all on cereals, Gaeumannomyces graminis var. tritici were divided into six subgroups by amplification with these two primers. There is some evidence for an association between host preference and RAPD subgroups but further work is needed to confirm this and to determine the importance of these subgroups. This fast and easy method is a useful tool for investigating the occurrence and distribution of this pathogen and for studying changes in the populations of species and subgroups of Gaeumannomyces in cereal cropping systems

Genetic variation, pathogenicity and mycelial growth rate differentiation between Gaeumannomyces graminis var. tritici isolates derived from winter and spring wheat

“…However, the biggest differences in linear growth rate were observed at temperatures lower or higher than optimum. RAPD markers revealed DNA polymorphism suitable for assessing differences among isolates examined confirming results published previously (Augustin et al, 1999;Weber et al, 2005). Considering that spring wheat roots are naturally infected by Ggt at temperature about 5°C, it is possible that isolates originated from them are more sensitive to higher temperature.…”

“…(Fouly et al, 1996;Augustin et al, 1999;Bryan et al, 1999;Ulrich et al, 2000a;Weber et al, 2005), Rhizoctonia spp. Random amplified polymorphic DNA (RAPD) is an effective and powerful method for determining intraspecific genetic variation.…”

Analysis of Mycelial Growth Rates and RAPD‐PCR Profiles in a Population of Gaeumannomyces graminis var. tritici Originating from Wheat Plants Grown from Fungicide‐treated Seed

“…Significantly, similar divisions of take‐all fungus populations into two main groups have been reported by other researchers, some of them using RAPD analysis. Augustin et al. (1999) used RAPD markers to differentiate G. graminis at the intravarietal and intervarietal levels.…”

Gaeumannomyces graminis, the take‐all fungus and its relatives

“…Various research groups have used RAPD analysis to discriminate between Gaeumannomyces and Phialophora species, varieties and isolates (Augustin et al ., 1999; Bryan et al ., 1999; Fouly et al ., 1996; Ulrich et al ., 2000; Wetzel et al ., 1996), and to identify subgroups within G. graminis varieties (Augustin et al ., 1999; Bryan et al ., 1999; Fouly et al ., 1996). RAPD analysis also successfully discriminated Gaeumannomyces spp., and some close relatives, from other darkly pigmented fungi commonly found on turf‐grass roots (Wetzel et al ., 1996).…”