Plant Pathology (2006) 55, 494-504
O.A. Akinsanmi, D. Backhouse, S. Simpfendorfer and S. Chakraborty (2006)
Genetic diversity of Australian Fusarium graminearum and F. pseudograminearum
Plant Pathology 55 (4), 494-504
Abstract: Genotypic diversity in Fusarium pseudograminearum and F. graminearum from Australia and the relationship between diversity and pathogen aggressiveness for head blight and/or crown rot of wheat were examined. Amplified fragment length polymorphism (AFLP) analysis revealed a high level of genotypic diversity within each species. Sixty-three of the 149 AFLP loci were significantly different between the two species and 70 of 72 F. pseudograminearum and 56 of 59 F. graminearum isolates had distinct haplotypes. When head blight and crown rot severity data from a recently published work on isolates representing the entire range of aggressiveness were used, only the genotypic diversity of F. pseudograminearum was significantly associated with its aggressiveness for the two diseases. Cluster analyses clearly demonstrated the polyphyletic structures that exist in both pathogen populations. The spatial diversity within F. graminearum was high within a single field, while frequent gene flow (Nm ~ 14) and a low fixation index (Gst = 0·03) were recorded among F. pseudograminearum isolates from the adjacent states of New South Wales and Queensland. The differences in population structure between the heterothallic F. pseudograminearum (teleomorph G. coronicola) and the homothallic F. graminearum (teleomorph G. zeae) were not as pronounced as expected given their contrasting mating systems. Neither species was panmictic or strictly clonal. This points to sexual recombination in F. pseudograminearum, suggesting that ascospores of G. coronicola may also play a role in its biology and epidemiology.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Olufemi A. Akinsanmi, David Backhouse, Sukumar Chakraborty
Research topic(s) for pests/diseases/weeds:
molecular biology - genes
Pest and/or beneficial records:
Beneficial | Pest/Disease/Weed | Crop/Product | Country | Quarant.
|
---|---|---|---|---|
Fusarium graminearum | ||||
Fusarium pseudograminearum | Australia (South+SE) | |||
Fusarium pseudograminearum | Australia (NT+QLD) |