Location: Forage Seed and Cereal Research2011 Annual Report
1a. Objectives (from AD-416)
Provide the seed industry with improved grass germplasm and management practices that reduce the impact of salinity, weeds, and diseases on seed quality and profitability. Identify bioactive compounds and genes that mediate the response of Lolium and Festuca to salinity related stress. Develop approaches to characterize, select and utilize components of host genetic resistance to pathotypes of the stem rust pathogen in Lolium. Determine whether a small molecular weight bioherbicide, produced by selected naturally occurring soil rhizobacteria (Pseudomonas sp.), that inhibits the germination of Poa annua can reduce the impact of this weed on seed production and turf quality. Develop molecular methods and tools that facilitate germplasm improvement for diverse uses. Develop a means to improve gene stability and minimize escape of transgenes in forage and turf grasses (Lolium sp.). Characterize genetics of host resistance to stem rust, and develop molecular markers for stem rust resistance in Lolium. Identify candidate genes that can be exploited to increase biomass of cool-season grass plants (Lolium sp.) to improve forage quality and source material for bioenergy production.
1b. Approach (from AD-416)
Conduct complex basic and applied research to improve the production and utilization of seed and grain from forage and turf seed cropping systems which include wheat. Traditional breeding and molecular genetics will be used to identify the genetic basis for stem rust resistance, factors that impact seed quality, flowering, and abiotic stress tolerance. Develop molecular and traditional approaches useful for altering plant developmental pathways and plant structures, and enhancing forage quality in end-use environments that differ from the seed-producing region. Bioherbicides that reduce weed presence in seed production and turf environments will be identified and characterized to enable commercialization of new products.
3. Progress Report
Progress was made on both objectives and their subobjectives which fall under National Program 215, Component 2, Pasture Management Systems to Improve Economic Viability and Enhance the Environment, Component 3, Sustained Harvested Forage Systems for Livestock, Bioenergy and Bioproducts, and Component 4, Turf Plant Materials. Progress on this project focuses on Problem D, the need for appropriate plant materials to improve economic viability and enhance the environment in pasture-based livestock systems, Problem H, the need for improved plant materials that enhance the environment while improving the economic viability of harvesting and using grasses and forage legumes for livestock, bioenergy and bioproducts, Problem J, the need for improved management practices that enhance the environment and increase the economic viability of growing, harvesting, and storing forage grass and lebumes for bioenergy and byproduct systems, and Problem K., the need for improved germplasm that is adapted to biotic and abiotic stresses and meets the economic and environmental objectives of turf producers and users. Under Objective D.2, we made significant progress by sequencing the complete genome of the strain of Pseudomonas fluorescens that secretes a germination arrest factor (GAF) with herbicidal activities against an array of grassy weeds. This sequence information permits direct comparison of gene sequences in closely related strains of the bacterium that do not produce GAF, enabling us to understand how GAF production is regulated. Under Objective H.2, we made progress by introducing genes encoding proteins that have potential to enhance yield and quality into model grass species and are currently assessing their effects. To address Objective J.1., we successfully operated a farm-scale gasification unit that produced a medium heating value syngas, and used the syngas to supplement diesel fuel required to fuel a generator. Significant progress was made in addressing Objective K.1 by our success in demonstrating an approach to disrupt specific gene function in forage and turf grass species through virus-induced-gene-silencing, and by the development of an in-house transformation system for Lolium. We also established the foundation for further progress in developing genetic resistance to stem rust by completing a genetic map for perennial ryegrass by adding an additional type of genetic marker to our preliminary map. The map was used to locate regions of the genome associated with quantitative resistance to stem rust on chromosomes 1, 6 and 7.
Kimbrel, J.A., Givan, S.A., Halgren, A.B., Creason, A.L., Mills, D.I., Banowetz, G.M., Armstrong, D.J., Chang, J.H. 2010. An Improved, High-Quality Draft Genome Sequence of the Germination-Arrest Factor-Producing Pseudomonas fluorescens WH6. Biomed Central (BMC) Genomics. 11:522-536.