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Fitopatogena gljiva Cryphonectria parasitica uzročnik je raka kore europskog pitomog kestena Castanea sativa Miller. Ova gljiva ujedno je prirodni domaćin virusa Cryphonectria hypovirus 1 (CHV-1), koji smanjuje virulentnost i sposobnost sporulacije zaraženih sojeva gljive. Hipovirus se može širiti samo između sojeva gljive koji pripadaju istom tipu vegetativne kompatibilnosti (VC) odnosno sadrže identične alele na svim vic lokusima, te s manjom učestalošću između gljiva u kojih je razlika samo u jednom od šest lokusa koji određuju raznolikost VC tipova u Europi. U ovom radu istraživane su populacije gljive C. parasitica s područja Ozlja i Kašta. Cilj je bio utvrditi raznolikost tipova vegetativne kompatibilnosti i postotak hipovirulentnih izolata bijele morfologije. U populaciji Ozalj dominantan VC tip bio je EU2 sa zastupljenošću 34%, zatim EU1 sa 19%. Manjim udjelom (svaki sa 4%) bili su zastupljeni VC tipovi EU14, EU39 i EU40. Postoje izolati neodređenog VC tipa, nekompatibilni sa dosada poznatima i čine 35% ukupnih izolata populacije Ozalj. U populaciji Kašt najzastupljeniji je tip bio EU1 s učestalošću 32%, zatim EU17 sa 16%, a manjom učestalošću (svaki sa 12%) prisutni su još EU2 i EU40, te EU3, EU5 i EU12 (svaki sa 4%). Neodređeni izolati čine 16% istraživane populacije Kašta. Vegetativna raznolikost je velika, a prisutnost hipovirusa je relativno mala, do 30%, što otežava prirodnu biološku kontrolu. Phytopathogenic fungus Cryphonectria parasitica is the causal agent of chestnut blight in the European chestnut Castanea sativa Miller. This fungus is also the natural host of the virus Cryphonectria hypovirus 1 (CHV-1), which reduces fungal virulence and sporulation ability. Hypovirus can spread only between fungal strains that belong to the same vegetative compatibility (VC) type, i.e. that contain identical alleles at all vic loci, and less frequently from the strains in which there's a a difference in only one of six loci which determine the diversity of VC types in Europe. In this research C. parasitica populations from Ozalj and Kašt area were analyzed. The aim was to determine the diversity of VC types and the percentage of hypovirulent isolates with white morphology. In Ozalj population the dominant VC type was EU2 which represented 34% of the total number of isolates, followed by EU1 which represented 19% of the total number of isolates. The prevalence of VC types EU14, EU39 and EU40 was 4% each. The VC type of 35% of isolates from Ozalj could not have been determined, they were incompatible with all of the known VC types. In Kašt population the most common type was EU1 (32% prevalence), followed by EU17 with (16% prevalence). EU2 and EU40 appeared less frequently (each with 12% prevalence) as well as EU3, EU5 and EU12 (each with 4%). Undetermined isolates constituted 16% of the studied Kašt population. Vegetative diversity was high and the presence of hypovirus was relatively low, up to 30%, which makes natural biological control difficult. |
