CAREER: Rapid stem rust resistance responses in barley; non host resistance mechanisms

North Dakota State University Fargo, Fargo ND

Investigators

Abstract

Understanding genetic resistance of crop plants against microbial pathogens is important for world food security and sustainable agricultural practices. To effectively deploy genetic resistance against important pathogens in crops we must understand the mechanisms underlying the different layers of plant innate immune systems. This project will investigate the stem rust race Ug99 resistance mechanism in barley in order to characterize the underlying molecular pathways and protein interactions mediating resistance against this highly virulent race of stem rust, currently considered a threat to world food security. The investigators will utilize genetic, molecular and biochemical approaches to answer the question of what mechanisms are responsible for resistance and if they have the characteristics of the more durable non-host type of resistance. The function of the genes involved and the timing of the resistance response indicate that the only known Ug99 resistance mechanism in barley, the rpg4/Rpg5 locus, is possibly a remnant of a multilayered non-host resistance mechanism. Thus, the investigators hypothesize that barley is a recent host of wheat stem rust and this pathosystem has not resulted from ancient co-evolution between the pathogen and the host. The investigators expect to elucidate the molecular mechanisms involved in the response and determine if it is an early non-host type of resistance. This information will fill gaps in the limited knowledge of plant innate immune systems and also be utilized to deploy more effective and durable resistance in important cereal crops including wheat and barley. The project will be utilized to recruit and train the next generation of molecular plant pathologists with special emphasis on peoples underrepresented in science, technology, engineering and mathematics. The cutting edge research tools and techniques used in the project and mentoring by the lead investigator will give undergraduate and graduate students an excellent educational opportunity.