Asia mountain Rosa rust - Phragmidium butleri

This rust attacks species of Rosa native to Asia. None of these host species are related to species of common ornamental roses, thus this rust species does not appear to be a threat to the North American rose industry.

Phragmidium butleri Syd. & P. Syd. 1907

Spermogonia unknown.

Aecia on stems and fruits, confluent over infected areas to 10 mm or larger, orange-yellow when fresh; paraphyses not seen; aeciospores globose, obovoid, ellipsoid or irregular, 18-43 × 15-28 µm, wall about 1.5-4 µm, thick, hyaline, contents yellow when fresh, minutely verrucose.

Uredinia hypophyllous (on lower surface of leaves), scattered, minute; paraphyses clavate, incurved, hyaline, up to 50 µm long, 7.5-15 µm, wide, wall slightly thicker at dorsal apical side, up to 5 µm; urediniospores globose, subglobose, obovate or ellipsoid, 17-35 × 15-25 µm, wall about 2 µm thick, hyaline, contents yellow when fresh, minutely and densely verrucose-echinulate, germ pores obscure.

Telia hypophyllous, scattered, minute, black, pulverulent; teliospores 70-90 × 25-30 µm, cylindrical, 7-10 celled, with a 5-8 µm long, hyaline papilla at apex, rounded below, wall 4-6 µm thick, dark chocolate brown, verrucose, not constricted at the septa, pores 2-3 in each cell; pericels hyaline, pale near spore, up to 108 µm long, swelling in the lower part.

See Wei (1988) for a more detailed description.

Host range: On Rosa subfamily Rosoidae, specifically R. brunonii, R. leschenaultiana, R. macrophylla, R. sweginzowii and Rosa spp. These native species are not of great economic importance.

Geographic distribution: At high elevations in Asia (China-Tibet, India-Kashmir, Punjab, Pakistan)

References:

Ahmad, S. 1956. Uredinales of West Pakistan. Biologia (Lahore) 2: 27-101.

Arthur, J.C., and Cummins, G.B. 1933. Rusts of the Northwest Himalayas. Mycologia 25: 397-406.

Ragunathan, A.N., and Ramakrishnan, K. 1973. Rust fungi of Madras State. VII. Kuehneola, Hamaspora, Phragmotelium, Phragmidium, Diorchidium, Ravenelia, Hapalophragmium and Nyssopsora. Mysore J. Agric. Sci. 7: 73-86.

Wahyuno, D., Kakishima, M., and Ono, Yoshitaka 2002. Aeciospore-surface structures of Phragmidium species parasitic on roses. Mycoscience 43: 159-167.

Wei, S.X. 1988. A taxonomic study of the genus Phragmidium of China. Mycosystema 1: 179-210.

Zhuang, J.-Y., and Wei, S.-X. 1994. An annotated checklist of rust fungi from the Mt. Qomolangma region (Tibetan Everest Himalaya). Mycosystema 7: 37-87.

Zhuang, W.-Y., Ed. 2005. Fungi of northwestern China. Mycotaxon, Ltd., Ithaca, NY, 430 pages.

Nomenclature

Specimens in BPI

Additional distribution data

Suggested citation: Yun, H.Y. Systematic Mycology and Microbiology Laboratory, ARS, USDA. . Invasive Fungi. Asia mountain Rosa rust - Phragmidium butleri. Retrieved November 21, 2009, from http://nt.ars-grin.gov/sbmlweb/fungi/index.cfm .