Widespread Distribution of Apple mosaic virus on Apple in Turkey.

From 2002 to 2003, symptoms suggestive of Apple mosaic virus (ApMV; a member of the genus Ilavirus) infection on apple (Malus pumila L.) trees were observed in orchards in the central Anatolia Region of Turkey. Symptoms on leaves included pale-to-bright cream spots, mosaic, and yellowing on the leaves. A survey was conducted during May and June in three provinces (Isparta, Karaman, and Niğde) for disease symptoms. Leaf samples from apple cvs. Anna, Gala, Gold Star, Golden Delicious, Granny Smith, Jonathan, Starking, and Rajka were collected and tested for the presence of ApMV with specific antisera (Agdia, Elkhart, IN) using the manufacturer's protocol for double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA). ApMV was found in 68.3% of 461 samples tested. The number of samples for each cultivar tested and percent positive for ApMV were as follows: 22 (9.1%), 34 (8.8%), 22 (13.6%), 30 (73.3%), 270 (95.5%), 46 (54.3%), and 22 (9.1%) for cvs. Anna, Gala, Gold Star, Golden Delicious, Granny Smith, Starking, and Rajka, respectively. All 15 samples tested of cv. Jonathan were negative using DAS-ELISA. Samples that tested positive for ApMV were mechanically inoculated onto Chenopodium amaranticolor, C. quinoa, and Cucumis sativus leaves using an inoculum prepared by homogenizing leaves in phosphate buffered saline containing 2.5% (vol/vol) nicotine. Inoculated C. quinoa showed inconspicuous mottling, and Cucumis sativus showed chlorotic local lesions that progressed to systemic chlorosis and stunting. No symptoms were observed on inoculated C. amaranticolor as previously reported for ApMV (3,4). The presence of ApMV in C. quinoa and Cucumis sativus were verified using DAS-ELISA, but ApMV was not detected in C. amaranticolor. Although ApMV has been reported in several different crops in Turkey, there have been only two unsubstantiated reports of ApMV-infected apple in the country (1,2). This study conclusively demonstrates ApMV infection of apples in Turkey and suggests that it is widely spread. References: (1) Ü. Fidan. J. Turk. Phythopathol. 23:3, 127, 1994. (2) M. Özkan and S. Kurçman. Bitki Koruma Bül. 16:106, 1976. (3) S. J. Petybridge et al. Ann. Appl. Biol. 141:77, 2002. (4) T. Sano et al. Ann. Appl. Biol. 106:305, 1985.