Uromyces nyikensis on Gladiolus

Uromyces nyikensis is a microcyclic rust considered of plant quarantine importance in the United States. It only has been reported from the Nyika plateau in Zambia (Africa), where it is a minor disease.

Uromyces nyikensis Syd. & P. Syd., Ann. Mycol. 2: 27. 1904

Spermogonia, aecia and uredinia unknown.

Telia: amphigenous, along veins, sometimes on chlorotic spots, scattered, small, subepidermal, round to oblong, 0.3-1 mm long, up to 2 mm long, without paraphyses; teliospores variable in shape, subglobose to ovoid, frequently angular, 19-32 × 14-22 µm, smooth, cinnamon-brown, lighter brown toward base, wall 2-3 µm, apex round, truncate to umbonate, 3-9 µm, sometimes light brown; pedicel hyaline, smooth, up to 30 µm long.

Host: on leaves of Gladiolus erectiflorus Baker.

Geographic distribution: Zambia (Nyika plateau)

Specimen examined: on Gladiolus erectiflorus Baker (as Gladiolus nyikensis Baker), Zambia (Zambia/Malawi), Nyika plateau, leg. White (B 70 0005183) III, Type.

Two other species of Uromyces are reported on Gladiolus. Included in this series, Uromyces transversalis produces paraphysate sori that are transverse to the veins of the host. Uromyces gladioli is similar to U. nyikensis in the production of telia without paraphyses, but the teliospores of U. gladioli are larger, 22.5-35 × 20-25 µm. Additional rust fungi reported on Gladiolus include Uredo gladioli-büttneri, a species that lacks teliospores, and Puccinia gladioli and Puccinia maccleanii in which the teliospores are one-septate. These three rust species are considered quarantine plant pests for the U.S.

Nomenclature

Specimens in BPI

Additional distribution data

Suggested citation: Hernández, J.R. Systematic Mycology and Microbiology Laboratory, ARS, USDA. 2004. Invasive Fungi. Uromyces nyikensis on Gladiolus. Retrieved November 21, 2009, from http://nt.ars-grin.gov/sbmlweb/fungi/index.cfm .