Project Number: 5358-22000-038-00
Project Type: Appropriated

Start Date: Apr 30, 2012
End Date: Apr 29, 2017

Objective:
Objective 1. Discover and test germplasm that has genetic resistance to principal or emerging diseases in forage seed and wheat production. Subobjective 1.A. Develop an approach for evaluation of orchardgrass germplasm for resistance to choke disease. Subobjective 1.B. Identify germplasm of Lolium with resistance to rust diseases. Subobjective 1.C. Identify germplasm and increase seed for wheat and barley lines with resistance to stem rust Ug99. Subobjective 1.D. Identify genomic sequences in Brachypodium associated with non-host resistance to the wheat stem rust pathogen. Objective 2. Develop plant disease modeling tools to protect food supply and implement biosecurity strategies against rusts and other diseases of grass and wheat. Subobjective 2.A. Develop a model for timing of application of fungicides for control of ergot in Kentucky bluegrass. Subobjective 2.B. Determine the role of aphids in infection of orchardgrass by Epichloe typhina. Subobjective 2.C. Implement weather-based epidemiological model for stem rust of perennial ryegrass. Subobjective 2.D. Adapt ryegrass stem rust models to wheat stem rust.

Approach:
Genetic resistance to stem rust will be investigated in cereal crops by selection, breeding and field evaluations, and in grasses by genetic mapping, quantitative trait loci analysis and transcriptome analysis. Molecular markers for stem rust resistance in Lolium will be chosen and validated. Genetic sequences associated with initial response of Brachypodium to the stem rust pathogen will be determined. Greenhouse and field experiments will be used to detect genetic resistance to the choke pathogen in grasses, and to determine whether aphids play a role in the infection process for this pathogen. An epidemic model for stem rust in grasses will be validated and expanded to include overwintering phenomena, and the grass stem rust model will be applied to wheat stem rust by experimental determination of critical parameters in greenhouse and field tests. Field experiments will be used to create a predictive model for infection by the ergot pathogen.