Location: Forage Seed and Cereal Research UnitTitle: Genetic diversity of Puccinia graminis f. sp. lolii from the Willamette Valley
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 10/3/2019
Publication Date: N/A
Technical Abstract: Stem rust disease caused by Puccinia graminis f. sp. lolii (Pgl) can cause complete crop failure in perennial ryegrass (Lolium perenne L.) and tall fescue (Festuca arundinacea Schreb.) grown for seed. Genetically diverse pathogens have a greater chance of overcoming control measures and may require multi-tactic disease control approaches. The objective of this study was to develop simple sequence repeat (SSR) markers that can be used to detect Pgl genetic diversity in the Pacific Northwest. Bulk urediniospores were collected from each grass species from locations near Corvallis, OR and DNA extracted. 85 SSR markers previously used to study stem rust on wheat (Puccinia graminis f. sp. tritici) (Pgt) were tested for amplification of Pgl DNA by thermal gradient PCR and agarose gel electrophoresis. It was found that Pgt primers amplified products in Pgl and are therefore useful to study Pgl diversity. A library of 46 SSR primers that amplified Pgl DNA has been created and 11 of the 46 primers generate SSR amplicons in only tall fescue Pgl. Additionally, banding pattern differences observed between the tall fescue bulk and the perennial ryegrass bulk indicate genetic differences. 224 single infection pustules from six fields throughout the Willamette Valley were collected. In future research, amplifications with select primers will be carried out as a multiplex using these samples.