FIRST REPORT OF STRAWBERRY MILD YELLOW EDGE VIRUS IN ARGENTINA

Numerous viruses have been mentioned infecting strawberry in a single or mixed infection. Many of them do not induce distinct symptoms in commercial cultivars, and often the only signs of infection are loss of vigor and reduced yield. Strawberry mild yellow edge virus (SMYEV) is one of the most widespread virus diseases of cultivated strawberry. Most of the grown cultivars are tolerant to infection with this virus and they do not show symptoms. However, infections by severe strains and mixed infection with other viruses lead to decline and to the development of virus symptoms. In strawberry production areas in Tucumán province, Argentina, strawberry plants were detected with dwarfism, stocky plants, mosaic, mottle, and leaf distortion. Plants were serologically tested for SMYEV by ELISA (Agdia kit). Of 21 symptomatic plants analyzed, 8 were positive (38%). Simultaneously, 454 symptomless plants were tested and 12 of them were found positive (2.6%). ELISA positive plants were further analyzed by immunocapture reverse transcription seminested polymerase chain reaction (IC-RT-seminested PCR) with specific primers for SMYEV. IC was performed with inmunoglobuline from Agdia kits. RT-seminested PCR reaction was done using three specific primers A, B, and C. Using this technique a fragment of the expected size was amplified. After graft inoculation of Fragaria vesca and F. virginiana indicator clones, necrosis, mosaic, epinasty, chlorosis, and distorted leaves were observed, along with other symptoms. Further research is being conducted to identify other possible viruses infecting this crop.