Alfalfa Mosaic Virus (AMV) is a plant virus with a wide host range including 600 plant species in 70 families. Hosts include field legumes, potato, tomato, and many ornamental potted plants. Symptoms vary from white flecks, wilting, malformation, dwarfing, ringspots, mosaics, mottle to necrosis depending on virus strain, host plants, stage of growth at infection, and environmental conditions. It is spread by at least 15 species of aphids, by seed, through pollen, by mechanical sap inoculation, and parasitic plants. There is no cure or treatment for plant viruses. Discard affected plants and control aphid populations. Start with certified, disease-free seed. Eliminate weeds in and around the greenhouse which may be hosts for AMV.