Response of Greenhouse-Grown Cucumber Cultivars to an Isolate of Zucchini Yellow Mosaic Virus (ZYMV). I. M.Al- Shahwan, Department, College of Agriculture, King Saud University, P.O. Box 2460, Riyadh 11451, Saudi Arabia. O. A. Abdalla, and M. A. Al-Saleh, Plant Protection Department, College of Agriculture, King Saud University, P.O. Box 2460, Riyadh 11451, Saudi Arabia. Plant Dis. 79:898-901. Accepted for publication 17 May 1995. Copyright 1995 The American Phytopathological Society. DOI: 10.1094/PD-79-0898.

Mechanical inoculation of 12 greenhouse-grown cucumber (Cucumis sativus) cultivars at the three- to four-leaf stage with an isolate of zucchini yellow mosaic virus (ZYMV) from Saudi Arabia resulted in various symptoms in 11 cultivars. Significant differences in plant height, fruit numbers, and fruit weight were observed between the inoculated and the control plants of the 11 affected cultivars. The cultivar Dina was asymptomatic, and no significant differences were observed between the inoculated and control plants for any of the parameters tested. Virus recovery test from cultivar Dina performed on the susceptible cultivar, Farol, together with lack of virus detection by enzyme-linked immunosorbent assay (ELISA) indicated that this ZYMV isolate did not infect Dina. However, inoculation of Dina at the cotyledon stage revealed minor symptoms that were confined to a few of the lower leaves, suggesting that Dina is resistant but not immune to this ZYMV isolate. Virus titer in Dina was low and the virus was restricted to the older leaves; whereas in Farol virus titer was considerably higher and the virus spread to all leaves.