VIROLOGICAL RESEARCH ON ?ILAVKA AND BLATINA LOCAL GRAPE VARIETIES

Viticulture is an important economic branch of Bosnia and Herzegovina, with 99% of the concentrated in Herzegovina, in Mostar and Li?tica vineyards. The most cultivated autochthonous Herzegovinian cultivars are ?ilavka (?; 50%) and Blatina (B; 40%). Currently, only standard planting material of CAC category can be purchased for these two cultivars in Bosnia and Herzegovina. The presence of 9 viruses in ?ilavka and Blatina cultivars (subjected already to individual clonal and sanitary selection) was assessed by ELISA and RT-PCR assays. Grapevine samples were collected from 20 vineyards and analyzed by both assays. The results showed a high incidence of virus infection and a relatively high number of single infections compared to multiple ones. GLRaV-3 was the most common virus (B - 64.20%, ?- 82.01%), followed by GFLV (B-54.26%, ? - 18.34%), and GLRaV -1 (B- 9.37%, ?-11.15%). Only in Blatina, GFkV was more represented (B-20.45%, ?-10.79%) compared to GLRaV-1. Other detected viruses were below 3%: GLRaV-4-9 (B-2.55%, ? -2.87%) and ArMV (B-0.56%, ? -1.89%), while GLRaV- 2, GVA and GVB were not found in the analyzed grapevine samples. The sequence comparisons and phylogenetic analyses of randomly selected GLRaV-3, GLRaV-1, GFLV, ArMV and GFkV isolates from both cultivars confirmed that all the sequenced isolates belonged to viruses detected previously by ELISA or RT-PCR. A study of the virus incidence conducted from 2011 to 2019 indicates the need to intensify the clonal and phytosanitary selection program, which would create a basis for further steps towards certified planting material for ?ilavka and Blatina cultivars.