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Gljiva Cryphonectria parasitica uzrokuje bolest rak kore pitomog kestena (Castanea sativa), te je u proteklom stoljeću ugrozila šume pitomog kestena diljem Europe. Prisutnost virusa Cryphonectria hypovirus 1 (CHV1) u populacijama gljive povezana je sa smanjenjem virulentnosti i blažim tijekom bolesti raka kore kestena, tj. tijekom vremena dolazi do uspostavljanja prirodne biološke kontrole bolesti. Kako bi se razumjela sama raznolikost gljive, analizirani su tipovi vegetativne kompatibilnosti (vc) ove gljive. U ovom istraživanju utvrđena je raznolikost istraživanih populacija pomoću Shannonovog indeksa (H') koji u populaciji gljive otoka Cresa iznosi 1,52, a u populaciji Istre 1,33. U populaciji C. parasitica otoka Cresa potvrđeno je šest različitih EU tipova, dok je u populaciji Buje, Istra potvrđeno pet. Također, 50% izolata gljive populacije otoka Cresa sadrži virus CHV1, dok u populaciji Istre virus nije nađen. Računalnom analizom sekvenci virusne RNA u creskoj populaciji gljive nađeno je devet haplotipova virusa. Analizirane sekvence virusa CHV1 imaju ukupno 39 polimorfizama u 985 nukleotida, te je potvrđeno da CHV1 u populaciji Cresa pripada talijanskom podtipu. Fungus Cryphonectria parasitica causes the chestnut blight disease in sweet chestnut (Castanea sativa) and has endangered the forests of sweet chestnut across Europe in the last century. The presence of Cryphonectria hypovirus 1 (CHV1) in fungal populations is connected to the reduction of the fungus’ virulence and a milder disease progress of chestnut blight, or in other words, a natural biological control is established over time. In order to understand the diversity of C. parasitica populations, an analysis of its vegetative compatibility (vc) types has been carried out. In this research, the diversity of the analysed populations was determined using the Shannon Diversity Index (H’), which was determined to be 1.52 in the fungal population of the island Cres, and 1.33 in the population of Buje, Istria. In the population of the C. parasitica of the island Cres six different EU-types were found, whereas in the population of Istria there were five. Moreover, 50% of the fungal isolates in the population of the island Cres were infected with the CHV1 virus, while in the population of Istria the virus was not found. By analysing CHV1 viral sequences in the population of Cres nine CHV1 haplotypes were found. Analysed sequences of the CHV1 virus have 39 polymorphisms in 985 nucleotides in total, and it has been determined that the CHV1 in the population of Cres belongs to the Italian subtype of the virus. |
