Location: Peanut ResearchTitle: Molecular Diversity of the peanut rust pathogen and its host Author
Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: 2/5/2013
Publication Date: 2/8/2013
Citation: Power, I.L., Tillman, B.L., Holbrook Jr, C.C., Ozias-Akins, P., Chu, Y., Arias De Ares, R.S., Culbreath, A.K. 2013. Molecular Diversity of the peanut rust pathogen and its host. Phytopathology 103(Suppl.1): S1.9. APS-Southern Division Meeting. Feb. 08-10,2013. Baton Rouge, LA. Interpretive Summary: None required.
Technical Abstract: Puccinia arachidis Speg is the causal agent of peanut rust, an important foliar disease of peanut in mainly low input peanut (Arachis hypogaea) producing countries with warm, tropical climates. Management of this disease in these countries is best realized through host resistance. Knowledge on the variability of the P. arachidis populations and the genetics of resistance to peanut rust should help us to effectively breed for stable resistance and thus effectively manage the peanut rust disease on the long run. Our objective was to determine the genetic polymorphism of P. arachidis and its peanut host. We evaluated sequences of the 5.8S-ITS2-28S region of P. arachidis isolates, collected from different regions in North America, South America, Central America and Asia, over different growing seasons. Preliminary results from the sequenced ITS region of the P. arachidis isolates do not indicate high genetic variability among the populations studied. To our knowledge, no information on the population structure of P. arachidis has been published. We furthermore characterized a selection of cultivated peanut genotypes, consisting of newly developed CRSP breeding lines, plant introductions and commonly grown cultivars, using SSR markers, previously identified as being able to detect high levels of polymorphism in peanut genotypes. The SSR markers used detected polymorphisms, however, none were able to distinguish resistant from susceptible peanut genotypes. These results will be presented and discussed.