Location: Forage and Range Research2011 Annual Report
1a. Objectives (from AD-416)
Evaluate and develop new germplasm and cultivars with enhanced seed production, germination, seedling vigor, salinity tolerance, winter hardiness, drought tolerance, and forage yield and quality and verify their ability to improve the sustainability and productivity of rangelands and pastures in the semiarid western U.S. • Objective 1: Collect, characterize, and evaluate grass, legume, and forb germplasm for genetic variation, adaptation, establishment and forage characteristics for use on Western rangelands and the rangeland-urban interface. • Objective 2: Describe and identify useful traits for improved forages, using physiological, biochemical, and genomic techniques. • Objective 3: Identify breeding and selection strategies to make plant selection more effective. • Objective 4: Develop germplasm/pre-variety germplasm/cultivars of grasses, legumes, and forbs with improved seed production, seedling establishment, forage production, persistence, and drought tolerance on rangelands of the Western U.S. • Objective 5: Develop and evaluate new plant cultivars that are more tolerant of biotic and abiotic stresses, more competitive, more persistent, and easier to establish and maintain in irrigated pastures in the Intermountain West. • Objective 6: Identify functional differences between invasive weeds and improved plant materials and evaluate potential methods and improved plant materials to diversify crested wheatgrass communities.
1b. Approach (from AD-416)
Combine expertise of a research team of plant breeders, plant physiologists, ecologists, and molecular biologists to acquire, characterize, and breed native and introduced range, pasture, low-maintenance turf, and bioenergy plant materials. There is a need for additional plant materials for the conservation, restoration, renovation, and reclamation of range and forage lands, including irrigated pastures. New releases will provide improved plants needed to establish and maintain economically and environmentally sustainable pastures and rangelands in the semiarid regions of the Intermountain West. Identify new sources of genetic diversity for cultivar development. Describe establishment of grasses, legumes, and forbs characteristics such as ability to sustain high quality forage on disturbed sites under grazing pressure when competing with invasive weeds, and important physiological and biochemical mechanisms. Molecular and cytogenetic approaches will be used to identify and characterize genetic mechanisms to improve efficiency of genetic enhancement and plant breeding. The competitive ability of released plant materials will be enhanced for traits such as seed germination, seedling vigor, rhizome development, salinity tolerance, drought tolerance, and forage quality and yield. The new plant materials will be evaluated for their improved ability to perform key ecological functions, satisfying the diverse needs of our customers. Evaluate potential invasiveness of new plant germplasm.
3. Progress Report
Scientists at Logan's Forage and Range Laboratory (FRRL) continue to focus on developing improved plant materials for turf, pastures, and degraded rangelands adapted to the western United States in native and introduced legumes (spreading alfalfa, prairie clovers, cicer milkvetch, Kura clover, sainfoin, birdsfoot trefoil, and Utah sweetvetch), forbs (small burnet and forage kochia), dryland range grasses (crested and Siberian wheatgrass (WG), bluebunch WG, thickspike WG, Snake River WG, western WG, Russian wildrye (WR), bottlebrush squirreltail, and slender wheatgrass), irrigated pasture grasses (tall fescue, orchardgrass, meadow brome, timothy, and creeping foxtail), and low-maintenance turf grasses (bluegrasses, fine fescues, and crested WG). Traits of interest include seed yield, germination, establishment, drought and heat tolerance, water stress, salinity tolerance, winter hardiness, turf quality, and increased forage yield and quality. A tall statured forage kochia was developed with enhanced winter grazing by livestock and wildlife, which could reduce winter feeding costs up to 25%. Animal feeding studies demonstrated that forage kochia is preferred by cattle over the poisonous plant species lupine. Pre-variety germplasm of western prairie clover Spectrum and Majestic were released for use in conservation plantings. Kentucky bluegrass germplasm was identified that maintained turf quality under half the recommended irrigation rate. Breeding efforts on irrigated pastures resulted in the development of three orchardgrass populations (early, intermediate, and late maturing), one creeping foxtail population, and one reduced irrigation meadow bromegrass population, currently under a CRADA. Molecular genotyping defined the relationships of Festuca valesiaca accessions and other species in the Festuca ovina complex of worldwide origin. Research was initiated to describe the mechanisms and genetic control of salinity tolerance in alfalfa and forage kochia. A genetic map of orchardgrass was generated with approximately 400 AFLP markers and over 90 SSR markers which were correlated with the late flowering trait. Genetic markers were developed in an Elymus mapping population for plant re-growth and greenness. Initiated genome-wide quantitative trait loci scans for biomass, forage quality, and morphological traits using integrated consensus maps of the experimental Leymus wildrye genetic mapping populations. Constructed cDNA libraries for transcriptome sequencing of polyploid intermediate wheatgrass and its diploid ancestors. Ongoing research to understand how different species and plant materials influence soil resources and invasion of weedy annuals has been a major thrust of research at Logan, UT. Recent research suggests that the performance of improved plant materials grasses, forbs, and shrubs reduce resource availability and resist invasion of cheatgrass and dyer's woad in the Great Basin. It has been demonstrated that diverse plant communities that contain shallow, intermediate, and deep-rooted species provided broader overall resistance to invasion by a variety of weedy species.
1. A taller forage kochia for fall and winter grazing by livestock. Winter feeding can account for up to 70% of the annual costs of livestock production in the western U.S. These costs can be reduced by extended grazing into the fall and winter, but dormant grasses lack the protein needed for livestock such as cattle. ARS researchers in Logan, UT, developed a new forage kochia that has high protein for winter grazing, is tall enough to stand above the winter snow level, and yields twice the forage as a previous variety. In addition, its seeds are larger and easier to establish than its predecessor. Based on public interest in a taller forage kochia, it is expected that it will have immediate impact as thousands of acres of private and public rangelands are reseeded every year. Additionally, the taller stature during the fall and winter should expand its usefulness to larger areas of the arid western U.S., thereby making livestock production more economically and environmentally sustainable and provide important habitat and forage for wildlife.
2. Native legumes for rangeland revegetation. Use of a diversity of species in revegetation programs is critical to combat weed invasion on rangelands in the western U.S. Currently, there is a lack of commercially available native legume species. Of particular interest is Western prairie clover, which is a perennial legume, found naturally in North America and which biologically provides its own nitrogen. ‘Spectrum’ and ‘Majestic’ pre-variety germplasms of Western prairie clover were developed and released by ARS researchers at Logan, UT, to the commercial seed trade. Spectrum was selected to represent plant materials from the central and eastern Columbia Plateau, central and eastern Blue Mountains, Northern Basin and Range, and Snake River Plain regions. Majestic was selected to represent plant materials from the western Columbia Plateau and Western Blue Mountains regions. Inclusion of these releases in conservation plantings will enhance biodiversity, provide forage for wildlife and livestock, and enhance habitat for pollinators. Land management agencies, ranchers, landowners enrolled in conservation programs, and the seed industry are primary beneficiaries of these releases.
3. Orchardgrass molecular map. Orchardgrass is among the top four grasses used worldwide as a forage base for livestock grazing because of its high forage quality. However, its inability to survive cold winters and its early flowering habit when grown with a legume are major limitations to its use in many parts of the U.S. In order to improve these traits, ARS scientists at Logan, UT, developed a genetic map of orchardgrass to better describe the genetic pathway and gene(s) associated with winter survival and flowering date (early versus late). Tools developed from this orchardgrass map will allow ARS scientist and others to identify gene(s) and enhance public and private plant breeder’s ability to improve orchardgrass for winter survival and flowering date. The identification of gene(s) and their locations on specific chromosomes will be utilized by other scientists working with other grass species.
4. Identification of drought tolerant Kentucky bluegrass germplasm. Given environmental factors associated with climate change such as drought and increased temperatures, there is a need to develop plant materials that use less water under increased and prolonged periods of drought. Urban water-use on landscapes continues to be a major sink for much of the western U.S. water resources. ARS scientists at Logan, UT, evaluated over 300 sources of turfgrasses for their ability to stay green given less water (about 50% of the irrigation that is often given to turf in a residential or park setting) in July and August. Older cultivars of Kentucky bluegrass and collections originating from Kazakhstan and Turkey had much better turf quality (green color) under reduced irrigation during July and August than many of the currently available plant materials. This material has been included in a breeding program to develop germplasm of Kentucky bluegrass that exhibits good turf quality under increased water stress associated with drought.
5. Native range grasses with increased seedling establishment. With the increased emphasis to use native plant materials in range revegetation programs in the western U.S. it is critical to identify genetically similar groups and develop native grasses that are competitive with invasive weeds, easy to establish, persistent, and produce high seed yield. This study was designed to evaluate the potential to improve genetically the seed and forage traits above in Snake River wheatgrass. Based on molecular genetic diversity data in Snake River wheatgrass, with the exception of plant collections originating from Enterprise, OR, all other collections and cultivars are not genetically different and represent a common gene pool from which to develop improved Snake River wheatgrass cultivars. Utilizing the data from this study, ARS scientists at Logan, UT, have developed a Snake River wheatgrass population with improved seed yield and seedling emergence under dry, harsh environments. Use of this plant material will increase the ability of native plants to compete and persist on dry, harsh disturbed rangelands currently being overrun with invasive annual weeds.
6. Influence of soil nitrogen on annual grass weed invasion on rangelands. Ongoing research to understand how different species and plant materials influence soil resources has been a major thrust of ARS researchers at Logan, UT, and Burns, OR. A primary challenge of restoring damaged rangelands that have frequent wildfires in the Great Basin is that invasive annual grasses utilize soil nutrients (nitrogen) at cooler temperatures, hence; they begin to grow earlier in the spring than desired perennial grasses. ARS scientists at Logan, UT, have demonstrated that new improved perennial grasses utilize soil nitrogen similar to the invasive annual grasses allowing them to compete earlier in the spring and displace invasive annuals. This research illustrates that improved perennial grasses are critical to resisting invasion by cheatgrass and that rangelands planted to different species in a mixture with a combination of shallow, intermediate, and deep rooting depths provide an overall resistance to invasion by weedy species.
7. Plant, soil interactions past, present, and future in the Great Basin. Plant community and soil interactions in the Great Basin are poorly understood for millions of acres that were formerly farmed for dry-land production of small grains or seeded with crested wheatgrass to stabilize disturbed lands. ARS researchers in Logan, UT, and in Burns, OR, in collaboration with Utah State University have described the plant, soil interaction with their farming history on these lands and developed means to assist land managers with classifying lands and developing land restoration protocol. This same study suggested that the influence of land cultivation that occurred nearly 100 years ago can still be observed by altered plant species composition and soil properties. These accomplishments improve the ability of land managers to recognize how past land uses affect the ability to influence plant community interactions in the future to secure agricultural sustainability and ecosystem integrity.
8. Reduced-input turfgrass collections from Russia. With the expanding human population in the U.S., demand for water is increasing for human consumption, landscaping, industrial purposes, and recreational uses, particularly in the water-limited western U.S. Typical high-input grasses for lawns, parks, and golf courses are becoming increasingly scrutinized for their high water and fertilizer use. ARS scientists from Logan, UT, collected turfgrasses from the Caucasus Mountains of Russia that maintained relative good turf quality (green) with low-inputs. These collections hold promise for use in reduced-input turf applications and were added to the National Plant Germplasm System and are available for use in U.S. turf improvement programs.
Bailey, D.W., Tabini, R., Waldron, B.L., Libbin, J.D., Al-Khalidi, K., Alqadi, A., Al Oun, M., Jensen, K.B. 2010. Potential of Kochia prostrata and perennial grasses for rangeland restoration in Jordan. Rangeland Ecology and Management. 63:707-711.