Source: TEXAS A&M UNIVERSITY submitted to NRP
ADVANCING BIOFUEL PRODUCTION, TX
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
SPECIAL GRANT
Reporting Frequency
Annual
Accession No.
0221491
Grant No.
2010-34619-20708
Cumulative Award Amt.
$279,200.00
Proposal No.
2010-01532
Multistate No.
(N/A)
Project Start Date
Aug 1, 2010
Project End Date
Jul 31, 2013
Grant Year
2010
Program Code
[BB-P]- Advancing Biofuel Production, TX
Recipient Organization
TEXAS A&M UNIVERSITY
750 AGRONOMY RD STE 2701
COLLEGE STATION,TX 77843-0001
Performing Department
Soil & Crop Sciences
Non Technical Summary
The U.S. currently imports 60% of its petroleum, which accounts for 45% of the total national trade deficit. Decreasing our dependence on petroleum imports by developing a renewable and sustainable, domestic biofuels industry will stimulate the economy, increase energy security, improve air quality, and decrease emissions of fossil CO2 and other greenhouse gases. The conversion of cellulosic feedstocks into ethanol has been recognized as an essential component of the overall biofuel strategy in the U.S. A key factor in meeting the U.S. government's "20 in 10" goals is the development of feedstock crops that can be grown at high biomass yield densities and at the same time exhibit superior characteristics for conversion to fuels and valuable chemicals. Another important factor for consideration of meeting these nearer term goals (like 20 in 10) is the availability of a cellulosic dedicated energy crop where cultivation, production, and harvesting practices have already been established. Sorghum fits these near-term needs because the agronomic production infrastructure already exists and producers in much of the U.S. are already familiar with the crop. In addition, an annual crop will be critical as insurance to fill short-term gaps in production for biofuel processing plants. Sorghum (Sorghum bicolor L. Moench) is an attractive dedicated energy crop because of its high productivity, drought tolerance, well established production systems, its genetic diversity, and the availability of a genetic system that greatly facilitates a breeding program. In addition the genetic structure and plant biology of sorghum allows for application of relatively simple genetic analysis compared to the genetic structure of other bioenergy crops such as switchgrass and miscanthus. Because the sorghum genome is relatively small and closely related to many of the other potential bioenergy species, the genomic analysis described herein should be applicable to other bioenergy crops, such as Saccharum, Miscanthus and Panicum species. The goal of the proposed program is to enhance our understanding of crop composition on bioenergy conversion, using sorghum (Sorghum bicolor L. Moench) as a model dedicated energy crop. Understanding the composition of this crop and its effect on conversion efficiency is crucial to the development of alternative energy sources. This will be accomplished by the agronomic evaluation of different sorghum types in several different production environments; biomass samples from each sorghum type will be collected from each location for compositional analysis and conversion using state of the art technologies. From this research, we expect to identify optimum sorghum genotypes for conversion.
Animal Health Component
75%
Research Effort Categories
Basic
(N/A)
Applied
75%
Developmental
25%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
2021630108125%
2022030108125%
2041630108125%
2042030108125%
Knowledge Area
204 - Plant Product Quality and Utility (Preharvest); 202 - Plant Genetic Resources;

Subject Of Investigation
1630 - Summer annual grasses; 2030 - Sweet sorghum;

Field Of Science
1081 - Breeding;
Goals / Objectives
(1) Detailed assessment of oligomeric sugar composition in aqueous extracts of sorghum. Initial studies will focus on utilization of recently-developed LC-MS(/MS) protocols for profiling carbohydrate oligomers. (2) Laboratory-scale investigation of conversion technology and operating conditions for optimal conversion of sorghum to biofuel. Initial studies will focus on evaluating whether water-soluble sugars contribute a net positive or negative effect on overall bioconversion efficiency. (3) Evaluation of existing germplasm and continued breeding programs to develop sorghum varieties with optimal fuel and chemical productivity. This activity will be significantly leveraged by results obtained in completion of objectives 1-2 above.
Project Methods
For objective 1, Oligomeric sugars will be accumulated onto solid phase extraction (SPE) cartridges prior to LC-MS analysis. Aqueous extracts will be loaded onto Hypercarb SPE cartridges (Thermo Scientific), and the cartridges will subsequently be rinsed with water prior to elution with methanol. The methanol will be evaporated to 5% of its original volume and injected directly onto a Prevail Carbohydrate ES column (Alltech). The column will be eluted using a linear mobile phase gradient consisting of 0.15% aqueous formic acid and acetonitrile. Oligomeric sugars will be monitored by negative ion electrospray mass spectrometry. Previous work has demonstrated that the predominant ions (m/z) generated for C6-oligomers with dp < 10 are represented by [M  H], [M  H + HCO2], and [M  Cl]. In contrast, doubly-charged ions are predominant for dp > 10. In previous work funded by the program, sorghum clearly accumulated water-soluble sugars at a much higher rate than either switchgrass or corn. While there are several likely explanations (including but not limited to maturity of biomass at harvest and intrinsic difference in growth and development), the differences are probably due to all of these factors. To further elucidate these differences, samples of switchgrass, corn and sorghum will be collected analyzed at different stages of growth (active growth, senescent and winter standing). Samples will be grown and collected from the Texas A&M Agricultural Research Farm in College Station. For objective 2, a laboratory-scale investigation of chemical pretreatment, followed by simultaneous saccharification and fermentation (SSF) to produce ethanol, will be carried out on sorghum materials that vary in terms of their water-soluble sugar content. The envisioned experimental design will enable a comparison of ethanol yield for a variety of feedstocks under pretreatment conditions of dilute acid and neutral pH. This study should provide an assessment of whether the presence of water-soluble materials is a net positive, negative, or neutral with respect to overall process efficiency for biomass-to-ethanol conversion. For objective 3, we plan to evaluate experimental bioenergy hybrids in three locations in Texas. These hybrids will be chosen to reflect several different types of sorghum including the bio-energy sorghum but also forage and grain sorghums as well. In these trials, agronomic traits such as biomass yield, percentage dry matter, plant height, maturity, lodging, and any disease and insect susceptibility. The test locations were identified and established based on prior knowledge of sorghum and where it is typically produced, given climatic parameters and production histories. In each location, whole plant biomass samples will be collected and prepared for analyses as described in objectives 1-2. Information generated on composition will be integrated with the agronomic data to determine the role that environment and genotype have on composition quality.

Progress 08/01/10 to 07/31/13

Outputs
Target Audience: End users of this research are primarily processor of industrial crops for bioenergy research purposes. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? In this project, two graduate students and two postdoctoral research associates were trained and developed in this program. How have the results been disseminated to communities of interest? Results have been dessiminated primarily through journal articles and book chapters. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Research trials with advanced bioenergy sorghums and sweet sorghums were planted and grown in three locations in Texas. These trials generated agronomic yield and quality data (including but not limited to biomass yield, plant height, maturity, lodging, disease reaction and biomass composition (as measured by NIR)). Biomass samples were analyzed for compositional analyisis of both dry matter and juice from the samples. A preliminary NIR calibration curve for the liquid fraction (including sugars) was developed in previous work; it is now being tested and improved using samples produced in this research trial. Analysis of multilocation trials reveals both a genotype and environment effect on composition of the biomass that influences the theoretical ethanol yields by more than 25%. The environment effect tends to be larger than the genotype effect in the set of sorghum germplasm under study.

Publications

  • Type: Book Chapters Status: Awaiting Publication Year Published: 2014 Citation: Rooney, W.L. 2013. Sorghum. In Cellulosic Energy Cropping Systems. D. Karlen ed., John Wiley and Sons, London. (in press).
  • Type: Book Chapters Status: Published Year Published: 2013 Citation: Stefaniak, T.S. and W.L. Rooney. 2013. Breeding Sorghum as a Bioenergy Crop. In Bioenergy Feedstocks: Breeding and Genetics. Saha, M., H Bhandari and J. Bouton (eds), John Wiley and Sons, Inc. New York, pp. 83-116.


Progress 08/01/11 to 07/31/12

Outputs
OUTPUTS: Research trials with advanced bioenergy sorghums and sweet sorghums were planted and grown in three locations in Texas. These trials generated agronomic yield and quality data (including but not limited to biomass yield, plant height, maturity, lodging, disease reaction and biomass composition (as measured by NIR)). Biomass samples were analyzed for compositional analyisis of both dry matter and juice from the samples. A preliminary NIR calibration curve for the liquid fraction (including sugars) was developed in previous work; it is now being tested and improved using samples produced in this research trial. Analysis of multilocation trials reveals both a genotype and environment effect on composition of the biomass that influences the theoretical ethanol yields by more than 25%. The environment effect tends to be larger than the genotype effect in the set of sorghum germplasm under study. PARTICIPANTS: Not relevant to this project. TARGET AUDIENCES: Not relevant to this project. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
Research trials continue to demonstrate that high biomass yields (> 10 dry tons/acre) can be produced under rainfed conditions in Texas. The photoperiod sensitivity means that these lines are growing vegetatively and will grow throughout the whole season provided suitable moisture. Thus, these hybrids are highly responsive to the environment, surviving under drought conditions and growing actively when moisture is available. Compositional analysis reveals difference between sorghum and other biomass sources such as corn stover and switchgrass, primarily in the quantity of soluble solids present. Data from multilocation trials reveals both a genotype and environment effect on composition of the produced biomass. In sweet sorghums, different maturity hybrids are essential to maintain a consistent and steady supply of fresh biomass over a complete harvest season. Based on initial testing, up to a four month harvest window can be produced using sweet sorghum in South Central Texas. In some of these regions, the addition of sugarcane will complement the sweet sorghum harvest season, resulting in a combined harvest window of almost eight months.

Publications

  • Felderhoff, TJ, SC Murray, PE Klein, A Sharma, MT Hamblin, S Kresovich, W Vermerris, and WL Rooney 2012. QTLs for Energy-Related Traits in a Sweet x Grain Sorghum [Sorghum bicolor (L.) Moench] Mapping Population. Crop Science 52:2040 doi: 10.2135/cropsci2011.11.0618
  • Stefaniak TR, JA Dahlberg, BW Bean, N Dighe, EJ Wolfrum, and WL Rooney. 2012. Variation in Biomass Composition Components among Forage, Biomass, Sorghum-Sudangrass, and Sweet Sorghum Types. Crop Sci. 52:1949 doi: 10.2135/cropsci2011.10.0534


Progress 08/01/10 to 07/31/11

Outputs
OUTPUTS: Research trials with advanced bioenergy sorghums and sweet sorghums were planted and grown in three locations in Texas. These trials generated agronomic yield and quality data (including but not limited to biomass yield, plant height, maturity, lodging, disease reaction and biomass composition (as measured by NIR)). Biomass samples were analyzed for compositional analyisis of both dry matter and juice from the samples. A preliminary NIR calibration curve for the liquid fraction (including sugars) was developed in previous work; it is now being tested and improved using samples produced in this research trial. Analysis of multilocation trials reveals both a genotype and environment effect on composition of the biomass that influences the theoretical ethanol yields by more than 25%. The environment effect tends to be larger than the genotype effect in the set of sorghum germplasm under study. PARTICIPANTS: Individuals that worked or were trained on this project include a post-doctoral research scientist, a research scientist, a research assistant and two graduate students. Collaborators on this project included Baylor University, Waco, Texas and National Renewable Energy Lab, Golden Colorado TARGET AUDIENCES: The target audiences for this research include: (i) engineers and procesors interested in biomass sources and its respective composition as it relates to both conversion and supply; (ii) sorghum geneticists and breeding programs interested in improving the composition of sorghum biomass for the bioenergy conversion programs; (iii) agronomists interested in the logistics of production; (iv) other biomass crops interested in accessing and developing tools for screening composition in their respective crops. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
Research trials continue to demonstrate that high biomass yields (> 10 dry tons/acre) can be produced under rainfed conditions in Texas. The photoperiod sensitivity means that these lines are growing vegetatively and will grow throughout the whole season provided suitable moisture. Thsu, these hybrids are highly responsive to the environment, surviving under drought conditions and growing actively when moisture is available. Compositional analysis reveals difference between sorghum and other biomass sources such as corn stover and switchgrass, primarily in the quantity of soluble solids present. Data from multilocation trials reveals both a genotype and environment effect on composition of the produced biomass. In sweet sorghums, different maturity hybrids are essential to maintain a consistent and steady supply of fresh biomass over a complete harvest season. Based on initial testing, up to a fourt month harvest window can be produced using sweet sorghum in South Central Texas and Louisiana. In some of these regions, the addition of sugarcane will complement the sweet sorghum harvest season, resulting in a combined harvest window of almost eight months.

Publications

  • Dahlberg, JA, E Wolfrum, B Bean, and WL Rooney. Compositional and agronomic evaluation of sorghum biomass as a potential feedstock for renewable fuels. J. Biobased Mater. Bioenergy 2011, Vol. 5, No. 4
  • Davila-Gomez, FJ, C Chuck-Hernandez, E Perez-Carrillo, WL Rooney, and SO Serna-Saldivar. 2011. Evaluation of bioethanol production from five different varieties of sweet and forage sorghums (Sorghum bicolor (L) Moench). Ind. Crops Prod. 33:611-616.