First Report of Tobacco Streak Ilarvirus from Honeysuckle.

A honeysuckle (Lonicera fragrantissima) shrub on the grounds of the former Plant Quarantine Station, Glenn Dale, MD, had chlorotic leaves on some shoot tips and a mild veinal chlorosis. Young leaves were triturated in buffer and rub-inoculated onto a series of potential indicator hosts. The virus incited necrotic local lesions and necrosis of the growing point in Chenopodium quinoa, etched ringspots on inoculated leaves of Nicotiana tabacum Xanthi nc, mosaic in Zinnia violacea, and chlorotic local lesions in Tetragonia tetragonioides. It did not infect any of 46 other herbaceous genera in families Cucurbitaceae, Fabaceae, Asteraceae, Solanaceae, or Brassicaceae. In gel diffusion tests with symptomatic leaves from tobacco, this virus reacted with antiserum to tobacco streak virus (TSV) HR strain, but did not react with antisera to alfalfa mosaic or with antisera to 12 viruses in the NEPO or Sobemovirus groups. Virus in leaves directly from the source shrubs, tested by enzyme-linked immunosorbent assay (ELISA), also reacted with TSV strain HF antiserum. Examination by electron microscopy of leaf dips revealed isometric particles 27 nm in diameter. The now 12-ft tall shrubs were grown from seed imported from China in 1914 (PI 40689). This species is now widely commercially available in the U.S. and grown for its fragrant late winter flowers (2). Viral-infected Lonicera spp. have been reported from Europe, Russia, Japan, and Canada (1). TSV is reported to be seed-borne in several other genera. Among other viruses reported from honeysuckle are Lonicera latent carlavirus, tobacco leaf curl geminivirus, alfalfa mosaic virus, tomato bushy stunt virus, a rhabdovirus, and an aphid transmitted virus. References: (1) R. W. Fulton. CMI/AAB Descriptions of Plant Viruses No. 307, 1985. (2) C. J. Perkin. Plantsman 12:215, 1991.