Fleck Virus Research Articles

Ampelometric, genetic and sanitary evaluation of CV. Vranac.

Vranac is autochthonous grape variety of Montenegro, being of significant importance for Montenegrin economy. Grape of this variety has been used for the production of red wine of top quality, very appreciated at the domestic and foreign market. Researching was done during three years in three locations in sub-region Podgorica. Beside ampelometric and uvologic indicators for vranac variety, average sugar content and total acids in must (22.08% and 4.95 g/l). Based on three years of investigation, an average largest number of bunches is noticed in population of vranac variety in location Nikolj crkva and the largest weight of bunch is measured in location Cijevna. The largest yield of grape per vine is reached in location Nikolj crkva. The content of total anthocyanins is medium high while the value of total flavonoids is high. Total polyphenols, proantocyanidols and flavans which react with vanilla reached medium values in years of researching. Using Elisa test, samples were tested for viruses: Arabis Mosaic virus (Ar); Fanleaf (FL); inf.mix (F+GVA+Lr3); Fleck virus (K), inf.mix (GVA+Lr3); Leafrool virus type1 (LR1); Leafrool virus type3 (LR3); inf.mix Lr1 + Lr3 (Lr1+Lr3). Turned out that of 145 tested samples 17 genotypes (11.72 %) are negative in virus testing. After Elisa test, these 17 samples were analyzed by PCR and indexing after which 4 genotypes (23.53 %) passed complete sanitary control and entered the individual clone selection procedure. The content of total anthocyanins is medium-high, while the value of total flavonoids is high. Total polyphenols, proanthocyanidol and flavans which react with vanilla have reached medium values in examined years.

The Assessement of Viricides Phytotoxicity used in Grapevine in Vitro

The aim of the study was to evaluate the phytotoxicity of antiviral drugs ribavirin (Rib) and oseltamivir (Os) used in controlled medium, in various concentration and period of exposure in the most dangerous grapevine viruses elimination processes by in vitro chemotherapy. Grapevine shoot cultures belonging to V. vinifera L. cultivars simple infected by fanleaf virus (GFLV), leafroll associated virus serotype 1+3 (GLRaV1+3), fleck virus (GFKV) were grown on M&S (1962) basic medium supplemented with antiviral chemicals for in vitro sanitation (Panattoni et al., 2006). Thus, increasing concentrations of Rib or Os were added to the proliferating medium for several subsequent subcultures. In the end treatment, regenerated shoots were transferred on free-drug rooting M&S medium. Phytotoxicity was evaluated on in vitro drug treated plantlets regarding multiplication rate and mortality for each viricide.

ウイルスフリーぶどう樹‘カベルネ•ソービニオン’及び‘カベルネ•フラン’のウイルス再感染について

We carried out a comparative test with mixed planting in the same field using virus-free and virus-infected (leafroll and fleck) vines of red wine-grape cultivars, ‘Cabernet Sauvignon’ and ‘Cabernet Franc’ (Vitis vinifera L.). Although initially virus-free vines were 7 or 8 years old, they have been reinfected.In this paper, seasonal changes in °Brix and titratable acidity of grape juice were investigated over a 3 year period (1985 to 1987, tree age: 6 to 8 years), and we detected and identified the viruses of these cultivars.The results are as follows;1. At full maturity, the °Brix values of the juices of virus-free ‘Cabernet Sauvignon’ and ‘Cabernet Franc’ were higher than those of virus-infected vines, in 1985 (6-year-old vines). However, in 1987 (8-year-old vines), the °Brix values of the virus-free varieties were lower than those of virus-infected vines.2. Titratable acidities of the juices of virus-free ‘Cabernet Sauvagnon’ and ‘Cabernet Franc’ were lower than those of virus-infected vines at full maturity in 1985. However, in 1987, titratable acidities of virus-free ‘Cabernet Sauvignon’ and ‘Cabernet Franc’ were higher than those of virus-infected vines.3. We found that the initially virus-free vines were reinfected by leafroll and fleck viruses. We think that in 1987, the infection by leafroll and fleck viruses caused the decrease in °Brix and the increase in acidity of juices, as well as light-colored fruits and red leaves in these initially virus-free vines.