First Report of Zucchini yellow mosaic virus in Cucumber (Cucumis sativus) in India.

In August of 2002, cucumber (Cucumis sativus L. cv. Himangi) plants grown in commercial fields in Pune, western Maharashtra, India, exhibited chlorotic spots, veinal chlorosis, mosaic, blister formation and shoestring symptoms on leaves, stunted growth, and distortion of fruits. Incidence of virus infection in the fields varied from 25 to 38%. Crude sap extracted from infected cucumber leaf samples was inoculated mechanically onto cucumber and indicator host plants. The inoculated glasshouse-grown cucumber plants showed virus symptoms similar to those observed in the field. The virus produced chlorotic local lesions on Chenopodium amaranticolor and chlorotic spots followed by veinal chlorosis, mosaic, vein banding, and leaf distortion on Citrullus lanatus, C. melo, C. sativus, Cucurbita maxima, Cucurbita pepo, Luffa acutangula, and Trichosanthes anguina. The virus did not infect Nicotiana benthamiana, N. glutinosa, and N. tabacum cv. White Burley (1,2). Cucumber and indicator plants were tested using direct antigen coating enzyme-linked immunosorbent assays. A positive reaction was obtained with monoclonal antiserum to Zucchini yellow mosaic virus (ZYMV) but not with antisera to Papaya ringspot virus-P, Cucumber mosaic virus, and Watermelon mosaic virus (Agdia, Inc., Elkhart, IN). The disease was observed again in the field during July to September 2003. Natural infection of zucchini (Cucurbita pepo) by ZYMV has been reported previously from India (3). To our knowledge, this is the first report of ZYMV in cucumber in India. References: (1) H. Pospieszny et al. Plant Dis. 87:1399, 2003. (2) R. Provvidenti et al. Plant Dis. 68:443, 1984. (3) S. J. Singh et al. Indian Phytopathol. 56:174, 2003.