Occurrence of graft transmissible virus diseases of the strawberry in the Czech Republic

Strawberry virus diseases were monitored using a leaf graft bioassay in 17 cultivars of strawberry Fragaria ananassa Duchesne in the Czech Republic. F ragaria vesca indicator clones revealed after grafting several symptoms of strawberry mottle, crinkle, vein banding, and mild yellow edge as well as o f mixed virus infections. Isometric virus-like particles (VLPs) ranging fro m 21 to 50 nm in diameter and flexuous filamentous VLPs (12 by 600-1400 nm) were observed by electron microscopy in negatively stained crude sap prepa rations. Our results confirmed the complexity of virus diseases of the stra wberry and represent the first report on the detection of strawberry mild y ellow edge disease (SMYED) and of filamentous particles in this crop in the Czech Republic.