Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 10/1/2007
Publication Date: 10/1/2007
Citation: Barbieri, M., Garvin, D.F., Marcel, T., Niks, R., Pecchioni, N. 2007. Mapping QTLs for leaf rust resistance in the model plant Brachypodium distachyon [abstract]. European Triticeae Genomics Initiative Workshop, October 1-6, 2007, Tenerife, Canary Islands, Spain. p. 02.13. Interpretive Summary:
Technical Abstract: Brachypodium distachyon has been proposed as a model system for functional genomics in temperate grasses because of its biological features and compact genome size. Molecular phylogenetic studies have suggested that the genus Brachypodium is closely related to Triticeae, which includes barley and wheat. This new model plant has been employed to analyze the genetics of resistance to leaf rust fungi caused by Puccinia spp., that are important diseases in cereals in many regions of the world, causing dramatic yield losses. We challenged five B. distachyon inbred lines with different Puccinia spp. to identify leaf rusts able to elicit disease symptoms. Interesting variation in resistance was observed following challenge of B. distachyon lines with a P. brachypodii isolate. All lines were successfully colonized by the fungus. However, different levels of partial resistance, defined as reduced epidemic development despite a compatible infection type, were observed between the lines. The aim of this investigation was to study the genetics of this vriation in leaf rust resistance. An F2 population of B. distachyon derived from a cross between the leaf rust susceptible line Bd1-1 and the partially resistant line Bd3-1 was phenotyped for resistance to P. brachypodii in the greenhouse. A linkage map is now being constructed using AFLPs to identify markers for QTLs associated with resistance. The long-term aim is to obtain a genetic picture of partial resistance to leaf rust in B. distachyon. This will allow comparisons to results obtained with known QTLs for resistance to P. hordei that have already been mapped in barley.