Viruses occurrence in raspberry cultivars grown in Romania

The occurrence of some virus diseases in Romania raspberry plantings was identified over 40 years ago but the further investigations have been limited. The research programme on the occurrence of Rubus viruses in experimental and commercial plantings was started in 1990. Between 1992 and 1995 field observations were done in F.R.I. Pitesti experimental plantations. A first systematic study on the occurrence of Raspberry ringspot virus (RpRSV), Strawberry latent ringspot virus, Tomato ringspot virus, Tomato black ring virus, Arabis mosaic virus and Raspberry bushy dwarf virus was initiated in 1996. Samples from plants with or without symptoms were collected and tested for virus infection by grafting on Rubus indicators (R. occidentalis 'Munger', R. phenicolasius and R. idaeus 'Norfolk Giant' and 'Malling Landmark') by mechanical inoculation to Chenopodium quinoa and by DAS-ELISA. Results of field observations, ELISA tests and biological tests will be presented. Characteristic virus symptoms were observed in 38.0% of the raspberry genotypes tested. The frequency of viruses in symptomatic plants was 18.7%, 10 (30.3%) of 115 samples were found to be infected with RLMV and RLSV, 7 (21.2%) with RLMV and 3 (9.1%) with RLSV only. Infection with only BRNV was recorded in 8 cultivars (24.2%). Mixed infections with either BRNV and RLMV or BRNV and RLSV, were revealed in 'Taylor' and 'Glen Clova'. ELISA tests showed that RpRSV was the most abundant virus infecting 24.7% of tested genotypes, and RBDV was identified with 6 genotypes ('Malling Leo', 'Glen Prosen', 'Lloyd George', 'Schoenemann', 85-2-6/14 and 'Carnival'). 'Carnival' cv. was identified as infected both to RBDV and also RpRSV.