causal agent of potato wart (Synchytrium endobioticum) is an obligate parasitic chytrid fungus. It is included as a quarantine pathogen in 55 countries with losses in susceptible cultivars reaching 50–100%
The aim of our study was to characterize the resistance to S. endobioticum pathotype 1 in cultivated
potatoes from a well characterized subset of the Vavilov Institute of Plan Industry collection and to determine whether this resistance is associated with cultivated potato species taxonomy with ploidy, with geographic distance or with a molecular marker Nl25-1400 proposed for molecular screening for resistance pathotype 1 of S. endobioticum Within the diversity of 52 landrace genotypes our work shows a lack of such predictive association with wart resistance High intraspecific variation of wart diseases resistance allows the selection of extremely resistant and susceptible genotypes available for future genetic and breeding studies. Key words marker-assisted
selection — potato — potato wart — resistance — Synchytrium endobioticum — taxonomy Synchytrium endobioticum (Schilb.) Perc is an obligate parasitic chytrid fungus causing potato wart disease. Crop losses with susceptible varieties can reach 50–100% (Hampson 1993, Melnik 1998) The fungus produces a thick-walled winter sporangium, 25–75 lm in diameter, and contains 200–300 diploid resting spores (pro-sori) (Tarasova 1978, OEPP/EPPO2004) In the spring, sporangia germinate to zoospores that can infectrelease motile tubers sprouts stolons and leaves. In infected cells,