Variability amongst strains of Fusarium poae assessed by vegetative compatibility and RAPD polymorphism

Abstract

Vegetative compatibility tests and random amplification of polymorphic DNA (RAPD) were used to assess genetic relationships amongst 54 strains of Fusarium poae obtained from various geographical regions. Twenty-seven strains were assigned to eight multiple member vegetative compatibility groups (VCGs), while the other 27 isolates were found to form single-member VCGs. There was a partial correlation between VCG and geographical origin, but the relationship was not always clear. However, no correlation was observed between the VCG and the host plant of origin. RAPD patterns were closely associated with VCGs in all cases. Members of VCGs that were interconnected by bridging isolates formed common branches in the phenogram constructed on the basis of the RAPD patterns, while strains that belonged to single-member VCGs were scattered throughout the phenogram. These data demonstrate that the combination of traditional and molecular methodologies allows reliable intraspecific subdivisions in an asexual fungus, which is a secondary invader of a wide range of host plants, and so has never been subject to the intense selection pressure of a single host species and lacks pathogenic subgroups.

ISSR markers detect high genetic variation among Fusarium poae isolates from Argentina and England

“…Furthermore, expected heterozygosis of the Argentinean and English populations were 0.998 (SD=0.003) and 0.993 (SD= 0.008), respectively. Previous DNA analyses using molecular markers suggested that there was a moderate level of genetic variability within F. poae (Kerényi et al 1997), perhaps because of the low number of isolates (54) and/or the use of RAPD markers. However, the AFLP analyses for Fusarium sporotrichioides, F. langsethiae and F. poae, resolved several dendrogram branches among F. poae isolates (Schmidt et al 2004).…”

“…Several molecular markers have been used to analyse the diversity of Fusarium plant pathogens at the genome level: amplified fragment length polymorphism (AFLP) in F. graminearum and F. asiaticum O'Donell, Aoki, Kistler & Geiser (Qu et al 2008), random amplified polymorphic DNA (RAPD) in F. graminearum and F. poae (Ouellet and Seifert 1993;Kerényi et al 1997), simple sequence repeats (SSR) in F. graminearum and F. culmorum (Vogelgsang et al 2009), and inter-simple sequence repeats (ISSR) in F. graminearum and F. culmorum (Mishra et al 2003(Mishra et al , 2004. AFLP analysis has been used also for studying relationships at taxonomic levels within a world-wide collection of F. sporotrichioides Sherbakoff, F. langsethiae Torp & Nirenberg and F. poae isolates (Schmidt et al 2004).…”

The Homologue ofhet-cofNeurospora crassaLacks Vegetative Compatibility Function inFusarium proliferatum

“…Non-nitrate-utilizing (nit) mutants were selected on complete medium containing 2% (wt/vol) potassium chlorate (17), were assigned to phenotypic classes (Nit1, Nit3, and NitM) based on growth on basal minimal medium with nitrate, nitrite, or hypoxanthine as the sole nitrogen source, and were tested for complementation as previously described (4).…”

“…(het and vic are used to indicate genes with similar functions and reflect differences in nomenclature, not function.) Vegetative incompatibility has been studied at least superficially in a large number of fungi, but in-depth studies have been limited to Neurospora crassa (12,34,35,36), Podospora anserina (7,10,29,30), Cryphonectria parasitica (6), Aspergillus nidulans (8), and several species of Fusarium (13,17,25,26). The het/vic genes are important for the recognition process to occur, but there are genes that affect the physical ability of hyphae to fuse that act upstream of the het/vic interaction (5,23) and other genes that are responsible for maintaining the stability of the heterokaryon that act following the het/vic interaction (23,40).…”

Molecular analysis of Spanish populations of Fusarium oxysporum f. sp. dianthi demonstrates a high genetic diversity and identifies virulence groups in races 1 and 2 of the pathogen

“…The random amplification procedure (RAPD-PCR) has shown efficiency in evaluating clustering within the Fod population, as previously described for other F. oxysporum formae speciales (Alves-Santos et al 2007;Jiménez-Gasco et al 2001), other Fusarium species (Kerényi et al 1997), and other genera (Pérez-Artés et al 2000). UPGMA analysis of the RAPD data separated Fod isolates into three clusters (A, B, and C), and this distribution was more related to the aggressiveness than to the race of the isolates.…”