Detection of Infectious Tomato Mosaic Tobamovirus in Fog and Clouds

Tomato mosaic tobamovirus (ToMV) was detected by enzyme-linked immunosorbent assay and reverse transcription-polymerase chain reaction-blot hybridization (RT-PCR-BH) in cloud samples collected from the summit of Whiteface Mountain, NY, and in fog samples from two collection sites along the coast of Maine. The virus was subsequently transmitted to Chenopodium quinoa from a composite of RT-PCR-BH-positive concentrates. There was no apparent relationship between the presence of ToMV and sample collection date, volume, or pH. The RT-PCR products of three cloud and fog samples and one deionized water sample were identical to one another and to a stream water isolate of ToMV from Whiteface Mountain based on nucleotide sequencing of a 347-bp fragment within the coat protein gene and 99.1 and 72.9% similarity to ToMV-L and tobacco mosaic virus-vulgare, respectivelv.