Tropical American Mainsia Rubus rust - Mainsia rubi

This rust occurs on many species of Rubus in Mexico south to Peru. It has been confused with Gerwasia rubi and may be a synonyn of that species. All other species of Mainsia are now placed in Gerwasia.

Mainsia rubi H.S. Jacks. 1931

Uredinia hypophyllous, small, round or irregularly round, yellowish; urediniospores ellipsoid to broadly obovate, 20-33 × 18-24 µm, yellowish to hyaline, echinulate, germ pores 3-4.

Telia epiphyllous, numerous in circinating groups, round or irregularly round, 2-4 mm, white; teliospores irregularly fusiform, 34-45 × 12-19 µm, walls 1 µm thick, hyaline, pedicels short, hyaline, often deciduous.

See New York Botanical Garden (1912 as Spirechina rubi) for a more detailed description.

Host range: Rubus adenotrichos Schltdl., R. coriifolius Focke Rubus glaucus Benth. Rubus guyanensis Focke, Rubus laxus Focke, Rubus miser Liebm., Rubus pringlei Rydb., Rubus pringlei Rydb., Rubus shankii Standl. & L.O. Williams, Rubus trichomallus Schltdl.

Geographic distribution: Central America: Antigua & Barbuda (Kern, 1911); Costa Rica (Berndt, 2004); El Salvador (BPI, 1922); Guatemala (Arthur, 1918); Honduras (BPI, 1952). North America: Mexico (Alvarez, 1976). South America: Ecuador (BPI, 1918); Peru (Arthur, 1929).

Notes: Cummins & Hiratsuka (2003) suggested that this fungus is probably the same as Gerwasia rubi because both species have suprastomatal telia; however, this hypothesis has not been confirmed.

References:

Alvarz, M.G 1976. Primer catalogo de enfermedades de plantas Mexicanas. Fitofilo 71: 1-69.

Arthur, J.C. 1907. Uredinales. N. Amer. Fl. 7: 83-848.

Arthur, J.C. 1918. Uredinales of Guatemala based on collections by E.W.D. Holway. I. Introduction, Coleosporiaceae and Uredinaceae. Amer. J. Bot. 5: 325-336.

Arthur, J.C. 1929. Las Royas de los Vegetales (Uredinales) del Peru. Est. Exp. Agric. Soc. Nac. Agrar. Lima, Peru 2: 1-14.

Berndt, R. 2004. A checklist of Costa Rican rust fungi. Pages 185-236 in Agerer, R., M. Piepenbring, and P. Blanz. Frontiers in Basidiomycete Mycology. IHW-Verlag. 428 pg.

Cummins, G.B., and Hiratsuka, Y. 2003. Illustrated Genera of Rust Fungi. Third edition. American Phytopathological Society, St. Paul, Minnesota : 225.

Kern, F.D. 1911. The rusts of Guatemala - II. Mycologia 3: 288-290.

Nomenclature

Specimens in BPI

Additional distribution data

Suggested citation: Yun, H.Y. Systematic Mycology and Microbiology Laboratory, ARS, USDA. . Invasive Fungi. Tropical American Mainsia Rubus rust - Mainsia rubi. Retrieved November 21, 2009, from http://nt.ars-grin.gov/sbmlweb/fungi/index.cfm .