Soybean rust (Phakopsora pachyrhizi Syd. & P. Syd.) has been a major disease limiting soybean production in the tropical and subtropical areas of Asia, where yield losses ranging from 10 to 80% have been reported (8). The host range of P. pachyrhizi is broad, with over 90 species reported in the literature, including several economically important crops. Among these are common bean (Phaseolus vulgaris L.), scarlet runner bean (P. coccineus L.), lima bean (P. lunatus L.), cowpea (Vigna

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... a L.), pea (Pisum sativum L.), and lentil (Lens culinaris Medik.) (1, 17, 18, 22, 28) . As the pathogen spread through Africa and South America, it initially was reported on only soybean (Glycine max L.) and kudzu (Pueraria lobata (Willd.) Ohwi). However, it was identified on Phaseolus vulgaris, common bean, in South Africa during the 2004-05 growing season, where the pathogen was found in a germplasm evaluation trial adjacent to heavily infected soybean fields (5). The level of infection within the common bean germplasm trial was low. Few entries were infected with the pathogen, and the severity on infected leaves was much less than that observed in the adjacent soybean field. Phakopsora pachyrhizi first was reported in the continental United States in November 2004 (23). Since the initial find in Louisiana, soybean rust has been reported on soybean or kudzu in 12 states in the southeastern United States. The first report in the United States of P. pachyrhizi infection on a plant species other than soybean or kudzu was on Florida beggarweed (Desmodium tortuosum (Sw.) DC.) in southwestern Georgia (24), followed by a report on Phaseolus coccineus L. (scarlet runner bean), P. lunatus L. (lima bean), and two P. vulgaris (kidney bean) cultivars adjacent to a rust-infected soybean field in Quincy, FL (13). Physiological races in Phakopsora pachyrhizi were first described in Taiwan, where nine single-urediniospore isolates collected at three locations were inoculated on six soybean and five legume accessions, including common bean, Phaseolus vulgaris (12). All nine isolates produced susceptible lesions on the six soybean accessions, but were separated into six pathotypes based upon their reaction on common bean, asparagus bean, kidney bean, and short-podded yam bean. Physiological specialization had been identified in several wild legumes (4) and is well known in soybean (2, 3, 7, 21, 25) . The separation of Phakopsora pachyrhizi into two species (18), P. meibomiae (Arthur) Arthur and P. pachyrhizi, has caused some confusion in interpreting previous host range studies because P. pachyrhizi was the species name used for all isolates (1, 22, 28) . Analysis of the nucleotide sequence of the internal transcribed spacer region of the isolates used in host range studies done at the United States Department of Agriculture-Agricultural Research Service (USDA-ARS) Foreign Disease-Weed Science Research Unit (FDWSRU) Biosafety Level 3 (BSL-3) Plant Pathogen Containment Facility revealed that isolates from Asia were P. pachyrhizi, whereas isolates from Puerto Rico and Brazil were P. meibomiae (6). Many of the legume species evaluated in the original host range studies, including common bean, Phaseolus vulgaris, were more susceptible to Phakopsora meibomiae isolates from Brazil (BZ82-1) and Puerto Rico (PR) than the P. pachyrhizi isolate from Taiwan (TW72-1) (22, 28) . The common bean cvs. V3249-13-1C,