Transmission, Host Range and Virus-Vector Relationships of Chino del Tomate Virus (CdTV), a New Whitefly-transmitted Geminivirus of Tomato

Abstract

The transmission properties, host range, and virus- vector relationships of chino del tomate virus (CdTV), a new whitefly-transmitted geminivirus of tomato, are described. The virus is transmitted by B. tabaci, the sweet potato whitefly, but not by seed or sap. The virus infects members of the Asclepiadaceae, Leguminosae, Malvaceae, and Solanaceae. In virus-vector studies, minimum AAF and IAF times were 1 hour and 2 hours, respectively. The virus was retained by its whitefly vector for 4.5 and 7.3 days following 24- and 72-hr AAF respectively. Relative efficiencies of transmission for 1, 5, 10 and 20 B. tabaci were 15, 49, 84 and 100 percent, respectively. The chino del tomate (CdT), or leaf curl disease of tomato (Lycopersicon esculentum Mill.), was first reported in cultivated tomato fields in Sinaloa, Mexico in 1970-71 (4). Presently, it occurs in tomato production areas of the west coast of Sinaloa and may affect 100 percent of the plants in a field (1). The disease is characterized by curled and rolled leaves, thickened veins, a bright-to-subdued-yellow mosaic which varies with time of the year, stunting, and a reduced fruit set (1,3). Recently, a whitefly -transmitted geminivirus, CdT virus (CdTV), was implicated as the causal agent of the disease (1,3), but information concerning the biological nature of the virus is lacking. Here, we present the results of studies involving virus transmission, experimental host range, and virus -vector relationships.