Solanum nigrum can be a reservoir for tomato yellow leaf curl geminivirus
In Spain, tomato yellow leaf curl geminivirus (TYLCV - EPPO A2 quarantine pest) was first found in Almeria in 1992, and it is now present on tomato crops throughout the south eastern region of the country. In the region of Murcia, it was observed that many field-grown tomatoes were infected by TYLCV. In the vicinity of one severely infected tomato field, Solanum nigrum plants (weeds) showing severe leaf distortions and hosting colonies of Bemisia tabaci (EPPO A2 quarantine pest) were observed. Analysis showed that TYLCV was present in S. nigrum. In addition, it was shown in the laboratory that B. tabaci was able to transmit TYLCV from infected tomato plants to S. nigrum seedlings. The virus could then be acquired by B. tabaci and transmitted back from infected S. nigrum plants to tomato. The authors concluded that S. nigrum can a reservoir for TYLCV.
Sources
Bedford, I.D.; Kelly, A.; Banks, G.K.; Briddon, R.W.; Cenis, J.L.; Markham, P.G. (1998) Solanum nigrum: an indigenous weed reservoir for a tomato yellow leaf curl geminivirus in southern Spain.
European Journal of Plant Pathology, 140 (2), 221-222.