On April 7, 2006, the Hawaii Department of Agriculture identified gladiolus rust (Uromyces transversalis) on the leaves of cut gladiolus flowers from Florida. The infected plants originated from a 1400 acre production farm in Palmetto, Florida (Manatee County). On April 14 the Florida facility was confirmed positive for gladiolus rust and an Emergency Action Notification was put in place by USDA, APHIS, PPQ. Gladiolus rust is considered of plant quarantine importance in Europe and the United States.
Uromyces transversalis is a rust fungus native to South Africa. This pathogen has been reported from areas of southern Europe, Morocco, South America, Martinique, Australia, and New Zealand. In 2004 the fungus was found in gladiolus production areas in several Mexican states. The principal hosts of gladiolus rust are hybrid cultivars of Gladiolus grown for flower production, but the rust also attacks other tropical members of the Iridaceae: Crocosmia, Tritonia, and Watsonia. Gladiolus rust symptoms are found by examining the leaves and stems of the plant. The typical symptom is yellowish-orange protuberances that develop across the leaf veins. Spores can be spread on corms, rhizomes, and flowers of host plants contaminated with spores or on infected leaves and stems. In addition to human-mediated spread of spores through plant material, spores can also travel on the wind.
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This pest alert is from the Massachusetts Introduced Pests Outreach Project, a collaborative project between the Massachusetts DAR and the UMass Extension Agriculture and Landscape Program aimed at preventing the establishment of new pathogens and pests in Massachusetts. Visit the project website (http://www.massnrc.org/pests) for more information on emerging pests or to subscribe to pest alerts.