Structure of the Cochliobolus sativus population variability

• Published in: Plant pathology 2012-08, Vol.61 (4), p.709-718
• Main Authors: Leisova-Svobodova, L., Minarikova, V., Kucera, L., Pereyra, S. A.
• Format: Article
• Language: English
• Subjects: amplified fragment length polymorphism; Biological and medical sciences; Cochliobolus sativus; diversity; Fundamental and applied biological sciences. Psychology; Fungal plant pathogens; geneflow; index of association; linkage disequilibrium; Phytopathology. Animal pests. Plant and forest protection
• ISSN: 0032-0862; 1365-3059
• DOI: 10.1111/j.1365-3059.2011.02547.x

The genetic diversity of several local populations of the fungal pathogen Cochliobolus sativus, collected over 3 years from different regions of the Czech Republic, was examined using amplified fragment length polymorphism (AFLP). A high level of variability was found even among isolates from one lesion. Measures of multilocus linkage disequilibrium suggested that recombination has a minor impact on the genetic structure of populations. Cochliobolus sativus forms genetically divergent populations (FST = 0·33), indicating a low level of geneflow between populations. This was supported by a significant correlation between genetic diversity and geographical distances up to 80–100 km. The most likely explanation for the genetic variability is that the fungus forms conidia with highly variable chromosomal rearrangements. The differentiation observed among local populations implies that genetic drift, including a founder effect, combined with restricted migration generates the structure of C. sativus populations.