Soybean/maize Germplasm, Pathology, and Genetics Research Site Logo
ARS Home About Us Helptop nav spacerContact Us En Espanoltop nav spacer
Printable VersionPrintable Version     E-mail this pageE-mail this page
Agricultural Research Service United States Department of Agriculture
Search
  Advanced Search
Programs and Projects
 

Research Project: Soybean Disease and Pest Management

Location: Soybean/maize Germplasm, Pathology, and Genetics Research

Title: New Legume Hosts of Phakopsora pachyrhizi Identified from Field Studies in Florida

Authors
item Lynch, T - UNIV OF ILLINOIS
item Steinlage, T - UNIV OF ILLINOIS
item Miles, Monte
item Marois, J - UNIV OF FLORIDA
item Wright, D - UNIV OF FLORIDA
item Hartman, Glen

Submitted to: Plant Disease
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 14, 2008
Publication Date: N/A

Interpretive Summary: Soybean rust was first reported in the continental United States in November 2004. In 1992, Phakopsora pachyrhizi was reported to infect 86 species of legumes in the Papilionoideae subfamily. On 15 November 2006, 101 species of small-seeded legumes, predominately those found in soybean-growing areas of the United States, were transplanted into a field adjacent to infected soybeans in Quincy, FL. Leaf samples of nine species that had lesions and rust uredinia were confirmed positive for P. pachyrhizi. All are reported as hosts for the first time in the U.S. This information is important for plant pathologists and others interested in the host range of the fungus and the impact this may have on over wintering areas in the south where the host and the pathogen coexist.

Technical Abstract: Soybean rust was first reported in the continental United States in November 2004.In 1992, Phakopsora pachyrhizi Syd. & P. Syd. was reported to infect 86 species of legumes in the Papilionoideae subfamily. On 7 August 2006, 101 species of small-seeded legumes, predominately those found in soybean-growing areas of the United States, were planted into soil-less medium in a rust-free greenhouse in Illinois. On 7 September 2006, seedlings were transplanted into a field adjacent to infected soybeans in a randomized complete block design with three replications at the NFREC in Quincy, FL. On 15 November 2006, plant samples were collected, and leaves were examined using a dissecting microscope for sporulating uredinia. Leaf samples of nine species that had lesions and rust uredinia appearing to be that of P. pachyrhizi were sent to the USDA/APHIS/PPQ/NIS Laboratory, Beltsville, MD for morphological examination and confirmation by polymerase chain reaction using primers specific to P. pachyrhizi. All nine species were confirmed positive for P. pachyrhizi using both methods. These were Cajanus cajan (pigeonpea, PI 520598), Calopogonium caeruleum (jicama, PI 362125), C. mucunoides (calopo, PI 286288), C. mucunoides (calopo, PI 322302), Glycyrrhiza lepidota (American licorice, PI 215213), Medicago sativa subsp. sativa (alfalfa, PI 536536), Neonotonia wightii (PI 284804), Pueraria phaseoloides (tropical kudzu, seed from Guatemala), Teramnus labialis (blue wiss, PI 517204), Trifolium bejariense (Bejar clover, PI 284008). All are reported as hosts for the first time in the U.S. To our knowledge, C. caeruleum, G. lepidota, M. sativa subsp. sativa, P. phaseoloides, T. labialis, and T. bejariense have not previously been reported as hosts of P. pachyrhizi. This also is the first report of Glycyrrhiza and Teramnus genera as hosts of P. pachyrhizi.

   

 
Project Team
Noel, Gregory
Walker, David
Domier, Leslie
Hartman, Glen
 
Publications
   Publications
 
Related National Programs
  Plant Diseases (303)
 
Related Projects
   Monitoring Soybean Cyst Nematode Infecting Bacteria
   Characterization of Soybean Pathogens and Disease Management
   Monitoring Aerial Transport Phakopsora Pachyrhizi Spores
 
 
Last Modified: 02/10/2009
ARS Home | USDA.gov | Site Map | Policies and Links 
FOIA | Accessibility Statement | Privacy Policy | Nondiscrimination Statement | Information Quality | USA.gov | White House