Author
SOTIROVSKI, K - UNIV METODIJ,MACEDONIA | |
PAPAZOV, I - UNIV METODIJ,MACEDONIA | |
Grunwald, Niklaus - Nik | |
MILGROOM, M - CORNELL UNIV, NEW YORK |
Submitted to: Plant Pathology
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 2/1/2004 Publication Date: 4/1/2004 Citation: Sotirovski, K., Papazov, I., Grunwald, N.J., Milgroom, M.G. 2004. Low diversity of vegetative compatibility types and mating type of cryphonectria parasitica in the southern Balkans. Plant Pathology. 53:325-333. Interpretive Summary: Chestnut blight is a destructive disease of chestnuts that has devastated chestnuts in the US forests. This disease is caused by the fungus Cryphonectria parasitica. The genetic diversity in populations of the chestnut blight fungus, was determined throughout Macedonia and selected areas in Greece. We estimated vegetative compatibility groups (vc type); two isolates of the same vc type can reproduce sexually with each other. Nearly all of the 786 isolates from Macedonia were in a single vc type, EU-12; all 379 isolates from Greece were of the EU-12 type. Only six of 20 populations in Macedonia had more than one vc type. The diversity of vc types in the most diverse populations of Macedonia were comparable to the least diverse populations found previously in Italy. These results lead us to conclude that sexual reproduction does not occur in these populations. The lack of vc type diversity may indicate a high potential for the spread of hypoviruses, namely viruses affecting a fungus. This could be beneficial in terms of biologically controlling chestnut blight in Greece and Macedonia. Technical Abstract: The diversity of vegetative compatibility types and mating type was estimated in populations of the chestnut blight fungus, Cryphonectria parasitica, throughout Macedonia and selected areas in Greece. Nearly all of the 786 isolates from Macedonia were in a single vc type, EU-12; all 379 isolates from Greece were EU-12. Only six of 20 populations in Macedonia had more than one vc type. The diversity of vc types in the most diverse populations of Macedonia were comparable to the least diverse populations found previously in Italy. All but six of the 313 isolates assayed had the same mating type, MAT-1, and no perithecia of C. parasitica were observed in any population. These results lead us to conclude that sexual reproduction does not occur in these populations. The lack of vc type diversity may indicate a high potential for the spread of hypoviruses and successful biological control with transmissible hypovirulence. However, if sexual reproduction should occur in Macedonian populations, up to 32 vc types would be possible by recombination among vegetative incompatibility loci. |