Squash yellow leaf curl virus: a new poty-like virus transmitted by Bemisia tabaci in Oman
A severe virus disease affecting courgette was observed in Oman. Symptoms are characterized by yellow spots, veinal yellowing and leaf curling. It was noted that these symptoms are not very different from those induced by whitefly-transmitted filamentous viruses reported on cucurbits (which include so far, closteroviruses, potyviruses, carlaviruses and DNA-containing rod-shaped viruses). The virus found in diseased plants could easily be transmitted by mechanical inoculation and by Bemisia tabaci (EPPO A2 quarantine pest). Host range studies (28 plant species from 10 families) indicated that the virus is limited to courgette, pumpkin and Luffa aegyptiaca. By using electron microscopy, flexuous particles of 700 to 750 nm long, and pinwheel-like inclusion bodies could be observed in affected plant material. Serological studies revealed relationships with watermelon mosaic virus-2 potyvirus, but not with zucchini yellow mosaic potyvirus or papaya ringspot potyvirus (watermelon strain). The authors felt that the causal agent of the disease observed in Oman is a distinct virus (maybe a potyvirus) which is tentatively named squash yellow leaf curl virus.
Sources
Zouba, A.A.; Lopez, M.V.; Anger, H. (1998) Squash yellow leaf curl virus: a new whitefly-transmitted poty-like virus.
Plant Disease, 85(5), 475-478.