Disease Note.

Report of Rust Caused by Frommeella mexicana var. indicae on False Strawberry in Argentina. G. A. Costa, Departamento de Sanidad Vegetal. Facultad de Ciencias Agrarias y Forestales, Universidad Nacional de La Plata. C. C. 31 , 1900, La Plata, Argentina. B. L. Ronco, Departamento de Sanidad Vegetal. Facultad de Ciencias Agrarias y Forestales, Universidad Nacional de La Plata. C. C. 31, 1900, La Plata, Argentina. Plant Dis. 79:82. Accepted for publication 17 November 1994. Copyright 1995 The American Phytopathological Society. DOI: 10.1094/PD-79-0082B.

False strawberry (Duchesnea indica Focke) grows naturally in the humid riverside forests of Rio de La Plata (La Plata and Ensenada, Buenos Aires, Argentina) and is grown as an ornamental. A rust disease caused by Frommeella mexicana var. indicae J. McCain & J. Hennen (= Frommeella duchesneae (Arth.) Yohem, Cummins & R. L. Gilbertson = Frommea obtusa (Strauss) Arth. var. duchesneae (Arth.)) (1) was found on abaxial leaf surfaces, stems, and trailing vines of D. indica. In October 1985-1988 (when humidity is high and the temperature is moderate, 15-20 C), urediniospores collected from diseased plants were used to inoculate noninfected leaves of 25 2-mo-old plants grown in plastic pots in the greenhouse. After 7-8 days, sporulation occurred and disease spread rapidly on all plants. Pustulates, powdery and bright orange when fresh, contained urediniospores (17–19 ? 17–19 ?m). Teliospores were not found. Plants of D. indica declined in vigor when disease was severe. A voucher specimen has been filed in the Arthur Herbarium, Purdue University, West Lafayette, Indiana. This is the first reported case of this autoecious rust in the area of La Plata and Ensenada.