INVESTIGATOR(S): Rooney, W.; J. Mullet, S. Kresovich, D. Ware, P. Klein
INSTITUTION: Texas A&M University and Cornell University
NON-TECHNICAL SUMMARY: Future production of renewable transportation fuels will require a consistent supply of biomass produced specifically for biofuel production. There will likely be many sources of biomass and species will be selected for their ecological fit, and their production and processing capability. Sorghum (Sorghum bicolor L. Moench) has the potential to be one of the species dedicated to biomass production because of its high productivity, drought tolerance, established production systems, and its genetic diversity. Research activities to develop sorghums for biomass production have been limited in the past. The purpose of this research is to use traditional and biotechnological approaches to produce sorghum genotypes with the genetic potential for use in bioenergy production.
OBJECTIVES: Within this grant period our specific objectives are to: (1) annotate genes, pathways and regulatory networks identified in the sorghum genome sequence that are important for biomass generation, and (2) identify, map and clarify the function of trait loci that modulate accumulation and quality of biomass in sorghum
APPROACH: (Obj. 1) Genes encoding proteins involved in biochemical pathways important for biomass generation, and plant composition related to biofuel production (i.e., starch, lignin, sugar, cellulose and hemicellulose), will be identified and projected onto biochemical pathways using the database MetaCyc. The pathway projections will provide a baseline of information on sorghum genes involved in biochemical pathways related to biomass/drought tolerance thus aiding our downstream analysis of QTL and traits. Moreover, the information on sorghum biochemical pathways in Gramene can be readily compared to information on other cereals and other organisms via Gramene's comparative mapping tools. This will help identify gaps in our current knowledge of sorghum biochemistry and help identify pathways and genes that maybe useful to deploy in sorghum for biomass/bioenergy generation. (Obj. 2) The goals of objective 2 will be met in two approaches. First, grain, biomass, and carbohydrate yields will be measured in a population consisting of 175 recombinant inbred lines (RILs) (F5:6) from the cross of BTx623 (a high yielding early flowering grain sorghum) × Rio (a high biomass sweet sorghum). Plant growth parameters will be analyzed to obtain a baseline for downstream meta-analysis. These include plant height, flowering time and tillering, traits that likely modulate carbohydrate partitioning in various tissues and total biomass. Traits that affect grain yield, biomass (i.e. the tissue harvest index and distribution of grain, stem, and leaf weight), the composition of structural and non-structural carbohydrates, and the overall energy gain of the plant will be evaluated. A genetic map of this population will be created and based on this map, QTL analysis will be carried out using QTL Cartographer, Mapmaker/QTL, or a similar analysis program. Second, tall, late flowering forage sorghum hybrids have the highest potential for total biomass generation. We are identifying genotypes that have high yield potential and excellent combining potential. In parallel, a RIL population will be developed by crossing tall, photoperiod sensitive late flowering genotypes that vary in biomass accumulation to explore the genetic basis of biomass accumulation and composition traits in this material. The population will be analyzed for variation in growth characteristics (growth rate and partitioning of growth) during the extended vegetative phase, for variation in lodging, total biomass and components of biomass related to biofuel production as described above for the BTx623 × Rio population. This information will build a baseline of data on biomass production in tall, late flowering sorghums that have the highest potential for biomass production.
Name: Rooney, Bill
Phone: 979 845 2151
Fax: 979 862 1931