Pathogenicity on grapevine and sporulation of E. lata isolates originating from Serbia

Pathogenicity of four isolates of Eutypa lata originating from Serbia (VL 17, VL 27, VL 29, VL 30) and two French reference isolates (8F and BX 1.10), were examined and compared on unrooted cuttings of Cabernet Sauvignon. Additionally, susceptibility to infection by all six isolates of E. lata was tested on unrooted cuttings of six different grapevine cultivars including Riesling white, Opuzenska rana, Sauvignon, Radmilovacki muskat, Beogradska besemena and Negotinski rubin in greenhouse experiments. All tested isolates proved to be pathogenic on Cabernet Sauvignon. Moreover, each grapevine cultivar showed different degrees of susceptibility to infection depending on the E. lata isolate. The effect of different culture media (PDA, MA, GWA, YA, WA and TA) on both sporulation of E. lata isolates and germination of conidia was also studied. Sporulation occurred after 30 days in three media (PDA, MA, GWA) and after 2 months on WA. No sporulation was observed on YA and TA. The ability of conidia to germinate was assessed on PDA, MA, GWA and WA under continuous UV light. Calculation revealed that the average percentage germination of conidia was very low 0,15%