Wilt of Tobacco in Chile Caused by Verticillium dahliae. B. A. Latorre, Pontificia Universidad Católica, Casilla 6177 Santiago, Chile. V. Flores, and G. Marholz. Pontificia Universidad Católica, Casilla 6177, Santiago, Chile, Chiletabacos S. A., Casilla 267-V, Santiago. Plant Dis. 71:101. Accepted for publication 1 October 1986. Copyright 1987 The American Phytopathological Society. DOI: 10.1094/PD-71-0101B.
Verticillium wilt (V. dahliae Kleb.) of tobacco (Nicotiana tabacum L.) was confirmed in Chile during several outbreaks in 1985 and 1986, affecting burley tobaccos primarily but aLso flue-cured cultivars. Symptoms included interveinal chlorosis of the lower leaves, which gradually yellowed completely and dried out; wilting of one side of the leaves or one side of the entire plant; and dark brown discoloration of the vascular tissue of tbe main stems or leaf petiole. Isolations from discolored vascular tissue seeded on acidified potato-dextrose agar yielded V. dahliae. Burley 21 plants inoculated with five V. dahliae isolates were positive for wilt, chlorosis, and vascular discoloration. Plants were inoculated by dipping the roots in a conidial suspension (108 conidia / ml)just before transplantation into infested soil (sterilized soil + 5 ml of conidial suspension per plant). Unless the roots were injured, plants recovered. Although disease incidence in the field was considered moderate, the concern is that inoculum potential in the soil may increase rapidly because susceptible crops are commonly included in crop rotations.