Texas Switchgrass Collaborative: Difference between revisions
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==Switchgrass Field Trials== | ==Switchgrass Field Trials== | ||
[[jimswitch.jpg|thumb| | [[Image:jimswitch.jpg|thumb|right|Drought experiments on diploid switchgrass]] | ||
A large agronomic community is implementing field trials of switchgrass across the expected growing regions of the USA. This infrastructure provides a unique opportunity for collaborative research. The current research will be conducted at 10 sites. | A large agronomic community is implementing field trials of switchgrass across the expected growing regions of the USA. This infrastructure provides a unique opportunity for collaborative research. The current research will be conducted at 10 sites. | ||
Revision as of 10:35, 23 June 2010
About us
The Texas Switchgrass Collaborative is a group of researcher funded by the National Science Foundation and centered at the University of Texas at Austin. We are studying various aspects of the ecology, physiology, and genetics of switchgrass, a major candidate bioenergy crop. Our primary focus is to understand the mechanisms of drought tolerance in switchgrass.
Understanding genetic variation of drought tolerance
The effects of climate change during the next 50-100 yrs will largely determine shifts in habitat type and quality, as well as the potential to use habitats for biofuel production. Although decreasing precipitation is expected to reduce plant productivity, the severity of impact will depend on the magnitude and frequency of altered rainfall, physiological tolerance envelopes of species, as well as the ability of switchgrass to acclimate or adapt. As such, a major goal of climate change ecology is to determine responses of target plant species under realistic field conditions. Here, we will use sophisticated field rainout shelters and realistic planting densities to explore switchgrass responses to predicted climate. To understand gene expression responses to drought we will implement RNA-sequencing on various switchgrass varieties under different drought regimes.
We are currently screening multiple cultivars of switchgrass for their tolerance to drought at multiple sites in Central Texas. This research will be conducted at the Lady Bird Johnson Wildflower Center and the Brackenridge Field Laboratory in Austin, TX, as well as the USDA Grassland Soil and Water Research Laboratory in Temple, TX.
The primary goals of this project will be to 1) Estimate the environmental and genetic variability for drought-related traits, overall physiology, and performance among diverse Panium virgatum varieties grown under future climate environments; 2) Identify drought-tolerant P. virgatum varieties for further study and potential biofuel use; 3) Expand our understanding of switchgrass physiology x environment interactions as well as the degree of geographical genotype x environment interactions through collaborative field trails; 4) Predict switchgrass productivity with future climate change using the genomic, physiological, and ecological data from this work to parameterize simulation models; 5) Determine gene expression response to drought across ecotypes.
Development of diploid switchgrass as a model system
The agronomic development of switchgrass as a biofuel crop has focused primarily on Panicum virgatum. Unfortunately, P. virgatum is a complex polyploid (both tetraploid and octaploid series exist), has a large genome (1C > 1500 Mbp) and is thus not easily amenable to traditional molecular genetic studies. In contrast, the closely related diploid species Panicum hallii has a much simpler genome (~500 Mbp) and can provide a genetic reference to support and interpret parallel studies in P. virgatum. Importantly, P. hallii occurs over the same moisture gradient as P. virgatum in the southern Great Plains and has locally adapted mesic (var. filipes) and xeric (var. hallii) ecotypes.
We are currently developing P. hallii as a model genomic system through high-throughput genomic and transcriptome sequencing in collaboration with the Department of Energy Joint Genome Institute. Our goal is to understand the genetic basis of natural variation in drought tolerance and biofuel related traits through a combination of high-density genetic mapping with RNA-sequencing. This aim will be achieved by leveraging distribution of natural drought adaptations distributed along the steep cline in soil moisture across Texas and the desert Southwest.
Switchgrass Field Trials
A large agronomic community is implementing field trials of switchgrass across the expected growing regions of the USA. This infrastructure provides a unique opportunity for collaborative research. The current research will be conducted at 10 sites.
These sites include USDA-GSW, Temple, TX; USDA-ARS, Weslaco, TX; Texas A&M University, Kingsville, TX; USDA-NRCS, Nacogdoches, TX; USDA-NRCS, Knox City, TX; Konza Prairie Biological Station, Manhattan, KS; USDA-NRCS, Elsberry, MO; and three sites in AR.
Overall, the selected sites provide a range of variation in temperatures, day length, rainfall regimes, and soil series, and will complement the Temple and Austin precipitation manipulation experiments and bolster data for climatic envelope modeling. The physiological stress responses of the varieties are being quantified using the physiology and growth measurements. These data provide realistic values of plant parameters needed for the ALMANAC (see below), which will be used to simulate leaf area growth, nutrient uptake, and biomass production. Leaf samples will be collected from these sites as a source of additional material for genomics.
Important Information and Links
Protocols
Literature collection
The following link contains a list of Relevant Publications
People
Academic Labs
- Tom Juenger, University of Texas at Austin
- Christine Hawkes, University of Texas at Austin
- Tim Keitt, University of Texas at Austin
USDA
- Philip Fay, USDA Temple, TX
- James Kiriny, USDA Temple, TX
- Mari-Vaughn Johnson, USDA Temple, TX
Postdocs
- Eli Meyers
- Mike Aspinwall
- David Lowry
