Colombian datura virus: an emerging disease?
Dr P. Salamon (Hungary) brought the attention of the EPPO Secretariat to an emerging virus, Colombian datura virus, which might present a risk to solanaceous crops. He also kindly compiled most of the information which is presented below for EPPO. Colombian datura virus (Potyvirus, CDV) was first isolated and described in 1968 from Datura candida and D. sanguinea plants (both species were then classified under the genus Brugmansia) imported from Colombia to the USA. CDV has flexuous rod shaped particles of about 800 x 12 nm in size. It is transmitted by aphids (including Myzus persicae) in a non-persistent manner, as well as by mechanical inoculation and grafting. A virus isolated from Petunia in Germany in the 1990s and tentatively called ‘Petunia flower mottle virus’ was then showed to be identical to CDV. Symptoms of CDV on Brugmansia can include reduction in leaf size, vein banding, chlorotic flecking followed by mottling, reduction of plant size and occasionally flower discoloration. CDV infections may remain symptomless but when plants are stressed, leaf mottling and mosaic patterns may appear.
Situation in Europe
After its initial description in 1968, no more attention was given to this virus until 1996 when CDV was reported to occur in Germany and the Netherlands on Brugmansia plants growing in botanical, private and commercial collections. CDV was detected in 24 samples (collected from 1989 to 1995) of Brugmansia species and hybrids, as well as in 3 samples of Juanulloa aurantiaca, Petunia hybrids and Lycopersicon esculentum (tomato). In 1996, CDV also was reported to occur in 1 glasshouse of tomatoes in the Netherlands. Approximately 300 tomato plants (L. esculentum cv. Cabrion) showed growth reduction, foliar mosaic and fruit discoloration. Observations suggested these tomato plants had probably been contaminated by aphids which had acquired the virus from a large CDV-infected Brugmansia plant (the latter had overwintered in the same glasshouse). In 2004, CDV infections were detected in tobacco (Nicotiana tabacum) crops in Hungary, Germany and Poland. Affected plants showed conspicuous chlorotic and necrotic leaf symptoms. In Hungary, recent studies have showed that besides Brugmansia hybrids, CDV caused severe diseases in experimental fields of Cape gooseberry (Physalis peruviana) and was found naturally infecting pepino (Solanum muricatum) plants. Inoculation studies have showed that potato (Solanum tuberosum) could be a potential host of CDV, but no natural infections have been reported.
Situation in the USA, and other parts of the world
In the USA, no further records were made after the initial description and the virus was considered no longer present. However, in 2004 CDV was detected in 3 plants of Spiranthes cernua (Orchidaceae) maintained by a propagator in South Carolina, which displayed leaf mosaic. In 2003, CDV was detected on Brugmansia plants growing in a nursery in Florida and showing disease symptoms (foliar mosaic, faint chlorotic spots and rugosity). Preliminary studies on samples from other parts of the USA suggest that CDV is more widespread on Brugmansia than originally thought but no further details could be found in the literature.
In Australia, CDV was first detected in one nursery on Brugmansia plants in New South Wales, and subsequently in Victoria.
Finally, nucleotide sequence data of CDV isolates from Japan (tomato, 2004), Oregon (Brugmansia, 2007) and Canada (2008) have been deposited in GenBank. However, in the absence of any other supporting data, it is difficult to assess the situation of the disease in these areas.
Although much data is lacking on the host range, geographical distribution and more particularly on the economic impact of the disease in solanaceous crops, it seems that CDV is emerging in different parts of the world. More attention should probably be paid to the health status of ornamental Solanaceae, as these may act as inoculum sources for economically important crops such as tomato, tobacco and possibly potato.
Sources
Personal communication with Dr P. Salamon, Vegetable Crops Research Institute, Kecskemét, Hungary (2008).
Adkins S, Chellemi DO, Annamalai M, Baker CA (2005) Colombian datura virus diagnosed in Brugmansia spp. in Florida. Phytopathology 95(6 supplement), S2.
Adkins S, Chellemi DO, Annamalai M, Baker CA (2008) Colombian datura virus re-emergence in Brugmansia spp. in the US. Proceedings of the 12th International Symposium on Virus Diseases of Ornamental Plants, Haarlem, Nl, 2008-04-20/24, p 44 (abst.)
Fry CR, Zimmerman MT, Scott SW (2004) Occurrence of Colombian datura virus in the terrestrial orchids, Spiranthes cernua. Journal of Phytopathology 152, 200-203.
Kahn RP, Bartels R (1968) The Colombian datura virus - A new virus in the Potato virus Y group. Phytopathology 58, 587-592.
Lesemann DE, Preissel HG, Verhoeven JTJ (1996) Detection of Colombian datura potyvirus and two unidentified potyviruses in Brugmansia hybrids. Acta Horticulturae 432, 346-353.
Salamon P, Palkovics L (2003) [Viruses and virus diseases of cultivated and wild-growing Solanaceous plants in Hungary. 5. Occurrence, host plants and identification of Colombian datura virus]. Növényvédelem 39, 581-588 (in Hungarian).
Salamon P, Palkovics L (2005) Occurrence of Colombian datura virus in Brugmansia hybrids, Physalis peruviana L. and Solanum muricatum Ait. in Hungary. Acta Virologica. 49, 117- 122.
Schubert J, Doroszewska T, Chrzanowska M, Sztangret-Wisniewska J (2006) Natural infection of tobacco by Colombian datura virus in Poland, Germany and Hungary. Journal of Phytopathology 154, 343-348.
Strumpf T, Buckhorn R, Lesemann DE (2005) [Occurrence of the Colombian datura virus on tobacco in Germany]. Nachrichtenblatt des Deutschen Pflanzenschutz 57, 1-3 (in German).
Verhoeven, JTJ, Lesemann DE, Roenhorst JW (1996) First report of Colombian datura potyvirus in tomato. European Journal of Plant Pathology 102, 895-898.
INTERNET (last accessed 2008-09)
Australia. Department of Primary Industries. Victoria. Colombian datura virus (Industry Update, February 2008). http://search.dpi.vic.gov.au
National Center for Biotechnology Information (NCBI) GenBank. http://www.ncbi.nlm.nih.gov/
NAPPO Pest Alert System. Pest Alert (2006-06-06). Colombian datura virus expanding host range to other Solanaceous crops in Europe. http://www.pestalert.org/viewNewsAlert.cfm?naid=21