RECOVERING AND IDENTIFYING INFECTIOUS PLANT-VIRUSES IN GUTTATION FLUID

Tomato mosaic virus (ToMV) virions were recovered from guttation fluid of systemically infected tomato (Lycopersicon esculentum Mill.) and v isualized by electron microscopy. Similarly, pepper mild mottle virus (PMMV) particles were identified in guttation fluid of systemically in fected green pepper (Capsicum annuum L.). Infectivity of ToMV and PMMV in guttation fluid samples was demonstrated on local and systemic hos ts. As determined by enzyme-linked immunosorbent assay, the concentrat ion of ToMV in tomato guttation fluid was 0.9 +/- 0.2 mug.ml-1 and the concentration of PMMV in green pepper guttation fluid was 0.5 +/- 0.1 mug.ml-1. The occurrence of infectious, mechanically transmissible vi ruses in guttation fluid may be an important factor in the spread of p lant viruses in greenhouse crops.