title: Brachypodium distachyon-Cochliobolus sativus Pathosystem is a New Model for Studying Plant-Fungal Interactions in Cereal Crops.
abstract: Cochliobolus sativus (anamorph: Bipolaris sorokiniana) causes spot blotch, common root rot, and kernel blight or black point in barley and wheat. However, little is known about the molecular mechanisms underlying the pathogenicity of C. sativus or the molecular basis of resistance and susceptibility in the hosts. This study aims to establish the model grass Brachypodium distachyon as a new model for studying plant-fungus interactions in cereal crops. Six B. distachyon lines were inoculated with five C. sativus isolates. The results indicated that all six B. distachyon lines were infected by the C. sativus isolates, with their levels of resistance varying depending on the fungal isolates used. Responses ranging from hypersensitive response-mediated resistance to complete susceptibility were observed in a large collection of B. distachyon (2n=2x=10) and B. hybridum (2n=4x=30) accessions inoculated with four of the C. sativus isolates. Evaluation of an F2 population derived from the cross between two of the B. distachyon lines, Bd1-1 and Bd3-1, with isolate Cs07-47-1 showed quantitative and transgressive segregation for resistance to C. sativus, suggesting that the resistance may be governed by quantitative trait loci from both parents. The availability of whole-genome sequences of both the host (B. distachyon) and the pathogen (C. sativus) makes this pathosystem an attractive model for studying this important disease of cereal crops.
authors.affiliation: First, second, third, and fourth authors: Department of Plant Pathology, North Dakota State University, Fargo 58108; and fifth author: United States Department of Agriculture-Agricultural Research Service, Plant Science Research Unit, University of Minnesota, St. Paul 55108.
authors.forename: Shaobin
authors.initials: S
authors.lastname: Zhong
authors.forename: Shaukat
authors.initials: S
authors.lastname: Ali
authors.forename: Yueqiang
authors.initials: Y
authors.lastname: Leng
authors.forename: Rui
authors.initials: R
authors.lastname: Wang
authors.forename: David F
authors.initials: DF
authors.lastname: Garvin
mesh_terms: D001203:Ascomycota / Q000502:physiology*; D058431:Brachypodium / Q000502:physiology*; D018556:Crops, Agricultural; D002523:Edible Grain / Q000235:genetics / Q000382:microbiology; D001467:Hordeum / Q000382:microbiology*; D054884:Host-Pathogen Interactions; D056626:Inflorescence / Q000235:genetics / Q000382:microbiology; D008954:Models, Biological; D010935:Plant Diseases / Q000382:microbiology*; D018515:Plant Leaves / Q000235:genetics / Q000382:microbiology; D018547:Plant Stems / Q000235:genetics / Q000382:microbiology; D040641:Quantitative Trait Loci; D014908:Triticum / Q000235:genetics / Q000382:microbiology*