First Report of Rust Caused by Frommeella duchesneae on False Strawberry in Indiana. G. E. Ruhl, Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907. J. W. McCain, Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907. Plant Dis. 70:475. Accepted for publication 23 January 1986. Copyright 1986 The American Phytopathological Society. DOI: 10.1094/PD-70-475c.
False strawberry or Aztec Indian berry (Duchesnea indica Focke) is grown as an ornamental for hanging baskets and may escape as a weed. A rust disease on this plant caused by Frommeella duchesneae (Arth.) Yohem, Cumm. & Gilbn. (= Frommea obtusa (Strauss) Arth. var. duchesneae Arth.) occurs naturally as far north as Kentucky and Missouri and has been found in Michigan and Minnesota greenhouses. In May 1985, two diseased false strawberry plants that had been growing as escapes were sent from Fort Wayne and Richmond, Indiana, to Purdue University. The pustules, powdery and bright yellow when fresh, contained colorless, finely echinulate urediniospores measuring 16–19 × 15–17 μm. Herbarium specimens were examined to confirm the host identification (D. indica), and two specimens of Duchesnea collected from outdoor plantings (Rockport in 1938 and Muncie in 1974) were found to have previously unnoticed rust pustules. Our specimens extend the range about 250 mi northward for infections in wild plants. Vouchers are in Purdue's Arthur Herbarium.