Checkoff Research Projects

Research

The United Sorghum Checkoff Program is beginning to fund many research projects to improve yield, production profitability, genetic improvement and herbicide tolerance. This year alone, USCP will fund approximately $1.25 million in new research projects. The Sorghum Checkoff is creating several production guides and have initiated many other research projects.

2010 Research Projects

Bio Energy

Lead PI: Kun-Jun Han, Louisiana State University $29,890.00 Planting Management Impact on Sweet Sorghum as a Biofuel Crop

Project Summary:

Sweet sorghum is adapted to a broad range of environmental conditions which makes it adaptable over a large part of the US. The sugar enriched stalks can produce up to 40 tons of biomass so it has attracted attention as a desirable biofuel feedstock. Corn-based ethanol production has been dominant in biofuel production. However, starch in corn grain must be broken down into a fermentable sugar. This process requires energy input and makes corn-based ethanol production less efficient than ethanol production from sweet sorghum. Although sugar concentration is lower than sugarcane, fermentable sugar composition in sweet sorghum is advantageous for immediate fermentation with lower crystallization of the sweet sorghum sugars. Recent field research with sweet sorghum varieties at LSU Agricultural Center Research Stations demonstrated the potential of sweet sorghum as a biofuel feedstock in northern and southern Louisiana. The potential for significant yield in a relatively short growing period could be advantageous since bio-refineries will require steady feedstock supplies over a long period. The southern US has a long growing season and it may be possible to more fully utilize the whole season to enhance production from sweet sorghum. Theoretically, sweet sorghum seed will germinate when soil temperature is around 64 ^oF and northern Louisiana soil temperature reaches that level around the second week of March. Therefore early planting in March with harvest in July may make it possible to grow another crop during the season. Sweet sorghum yield and sugar quality responses to various planting dates and possible multiple harvests have not been studied extensively. Therefore, we are proposing an integrated study combining field research and advanced sugar analysis technology. Data related to sweet sorghum parameters such as yield, maturity, stalk leaf ratio and seedhead yield will be collected at research units in both northeast and southeast Louisiana. The Audubon Sugar Institute will measure juice yield, sugar composition and ethanol production from juice, seedheads, and bagasse. Sweet sorghum will be planted at approximately 2-week intervals from mid-March to May and also in early June and July. Some plants will be harvested in the early seedhead development stage thus allowing an anticipated ratoon crop while others will be harvested only at the more traditional stage of late seed development. This growth stage is known to be one of the highest fermentable sugar accumulating stages. The total fresh yield of juice extractable stalks and days required for reaching target harvest maturity will be recorded. Sweet sorghum stems will be weighed and milled for determination of stalk and juice production per area. Sugar content will be measured and fermentable sugars (glucose, fructose, etc.) characterized and evaluated for purity. The amount of recovered bagasse will be recorded and fermented after pre-treatment. Ultimately, this information will provide an understanding of sweet sorghum growth behavior, stalk yield, fermentable sugar production and potential ethanol from a wide range of plantings throughout the growing season. Results will provide an informational base for planning a system for utilization of sweet sorghum as a biofuel crop.

Lead PI: Donghai Wang, Kansas State University $42,810.00 Stabilization of sweet sorghum juice for year-round use

Project Summary:

The fuel ethanol industry in the United States continues to grow and will reach 10.5 billion gallons in 2009 (RFA, 2009a). Ethanol production still can not keep up with the increasing demand (RFA, 2009b). Congress mandates an increase in domestic renewable and alternative fuels production to 36 billion gallons per year by 2022 in the 2007 Energy Independence and Security Act, or EISA (Public Law 110-140). Biofuels usage will reach 20.5 billion gallons by 2015 and corn ethanol will be capped at around 15 billion gallons (CBO, 2009). Therefore, a big portion of that renewable biofuels must be produced from alternative feedstocks. Sweet sorghum with its prominent agricultural features such as low fertilizers and water requirements, shorter grow period, and high biomass yields (up to 20-30 dry tons/hectare) is a very promising energy crop (Geng et al., 1989; Rooney 2007). Furthermore, it is not a food crop and can grow on diverse marginal lands, so there will be no end-use and land-use conflict issues either. Approximately 40-45% of the sweet sorghum dry mass are fermentable sugars and starch (equivalent to corn yield of ~200 bu/acre). If all of them are converted to ethanol, potential ethanol yield could reach 600-650 gal/acre (comparing with 440-460 gal/acre of corn) (Wu et al., 2009). The greatest challenge for sweet sorghum as a feedstock for ethanol production is its short harvest period and the extreme instability of the juice. According to Report from International Conference on Sorghum for Biofuels (Houston, TX, 8/19-8/22, 2008), storage and transportation issues are more critical for sorghum than most other biomass feedstocks, especially for sweet sorghum due to its rapid change in sugar content or sugar degradation after harvest. Up to 50% of total fermentable sugars in sweet sorghum juices will be lost if stored at room temperature for a week (Wu et al., 2009). Similar ranges of losses have been reported for sugarcane industries (Solomon 2009). Cost effective processing approaches to significantly extent the storage stability of sweet sorghum juice will turn seasonal rush operation into a year-around production process, which will greatly benefit all sectors related with sweet sorghum ethanol production ranging from sweet sorghum growing farmers, feedstock logistic companies, and ethanol industry.

The long-term goal of this proposed research is to develop affordable processing techniques to extend the storage stability of sweet sorghum juice, so that sweet sorghum based ethanol facilities can be run year around rather than a seasonal operation. The short-term goal is to evaluate several approaches for their ability to extend the storage stability of sweet sorghum juice and establish a most cost effective process. The research will focus on 1) development of innovative devices to stabilize sweet sorghum juice; 2) characterizing the sweet sorghum juices after treated with different techniques; and 3) evaluating the storage stabilities and ethanol fermentation performance of the treated sweet sorghum juices.

The proposed research will deliver the state-of-the-art processing technology for stabilizing sweet sorghum juice. This would help sweet sorghum to play a bigger role in the fast growing bioethanol industry, to sustain the ethanol industry to realize the goal set by the 2007 EISA as well as to revive sweet sorghum related rural economy. The success of this project will generate informative data and knowledge for large-scale processing and storage of sweet sorghum juice for fuel ethanol production, extend the actual harvest period, and turn sweet sorghum ethanol plants from seasonal operation to year around production. Our proposed research addresses the Mission of USCP of “USCP commits to effectively investing checkoff dollars to increase producer profitability and enhance the sorghum industry” and this research addresses the technical area of “research the benefit and limiting issues for sugar conversion and storage in sweet sorghum” described in the RFP.

Lead PI: Jamie Foster, Texas AgriLife Extension Service/TAMUS $40,075.00 Fibrolytic Enzymes to Enhance the Use of Sorghum Silage for Lignocellulosic Feedstock

Project Summary:

The United States Federal government mandates production of 21 billion gallons of renewable fuel from non-corn sources to be blended with gasoline by 2022. This project will further the development of technologies allowing sorghum production to adapt to future lignocellulosic feedstock demands while promoting sorghum as a competitive biofuel feedstock. Two major limitations to ethanol production from lignocellulosic feedstocks are development of enzymes to break bonds between fibers and the storage of feedstocks. The environment, cultivar, type of material ensiled, and the use of fibrolytic enzyme additives all affect the ease of ethanol extraction from lignocellulosic material. Fibrolytic enzyme additives hydrolyze cell wall bonds which improves storage of silage, while simultaneously serving as a pretreatment for further processing to ethanol.

The overall goal of this project is to identify the effect of management practices, including environment, cultivar, whole plant versus dual crop, and post-harvest fibrolytic enzyme application, on the use of sorghum silage as a pretreated biomass feedstock for lignocellulosic conversion technologies. Objectives are to determine 1) whether an applied fibrolytic enzyme cocktail improves the aerobic stability, silage quality, and degradation of fiber; and 2) to evaluate sorghums dual crop potential when comparing the characteristics of silage made from the whole plant (including grain) versus the stover.

This experiment will consist of 3 replicated plots of 4 cultivars planted at 3 locations (Beeville, Kingsville, and College Station, TX). The sub-plot is the type of harvested material to be ensiled, either whole plant or residue after grain removal. At harvest, material will be chopped and ensiled as either no applied enzyme (control) or after enzyme is applied. Chemical composition of plant material will be measured pre- and post-ensiling; whereas, silage quality and aerobic stability will be measured post-ensiling. Results of this research will translate into information which improves the extraction of ethanol from sorghum lignocellulosic feedstock, thus enhancing the sorghum industry as a whole.

Cost of enzyme for treating 1 acre (or one ton) of silage is expected to be $15.00, an increase of digestibility of 5% should recover this cost. Ethanol must sell for $1.07 per gallon in order for it to be profitable and pretreatment to begin fiber hydrolysis is necessary to meet this economic threshold. Several target audiences will be impacted by the results of this research. Target audiences include: sorghum producers, lignocellulosic biofuel processors, dairy producers, and feedlot operators. Producers of sorghum for biofuels and processors of feedstock will benefit from information which may improve the storage longevity of sorghum silage and simultaneously decentralize pretreatment of sorghum silage for ethanol production. Throughout Texas, and much of the Southwestern United States, sorghum is stored as silage for feeder cattle and dairy cattle feed. Increasing digestibility of sorghum silage will decrease the amount of feed necessary to produce a pound of milk or meat, thereby reducing nutrient excretion.This information will be disseminated through resources already available to Texas AgriLife and the Texas A&M System, including websites, field days, and interaction between extension and research personnel and producers.

Breeding

Lead PI: Andrew Paterson, University of Georgia $33,475 Identification of Ma1, the gene that hinders utilization of exotic sorghum germplasm

Project Summary:

Critical problem. The single greatest hindrance to utilization of exotic germplasm in improvement of sorghum for temperate agriculture is that the vast majority of such germplasm flowers only at short daylength, as a result of the Ma1 gene conferring photoperiod sensitivity. Much effort in ‘conversion’ of exotic sorghums to day-neutral forms by a lengthy and tedious crossing program has rendered about 700 exotic sorghums more useful in breeding programs, however this remains only a tiny sampling of extant sorghum diversity.

Research approach. Over more than a decade of research, we ‘mapped’ the short-day flowering trait to a small region of the genome, sequenced the genome, scrutinized the ~30,000 genes in the sequence, and narrowed the list of candidates to about 400. In initial USCP funding to date, we have narrowed the target region to about 100 genes, and found tentative associations (albeit requiring further analysis) with one gene in particular. Herein, we seek to further test this association (and if need be seek and test other associations), by utilizing a ‘diversity panel’ of 384 genotypes that broadly samples worldwide sorghum diversity, provided by our cooperators H. Upadhyaya (germplasm curator), and C. T Hash (sorghum breeder) at ICRISAT. We expect the outcome to be the demonstration that different ‘versions’ (alleles) of one particular gene are closely correlated with differences in flowering time among members of the panel, indicating that the gene is Ma1. In addition, a fringe benefit will be to set the stage for the identification of the nearby dw2 gene that accounts for much of the tall stature of exotic sorghums.

Potential benefits/impact. Identification of the specific gene responsible for short-day flowering would empower the use of a variety of mechanisms to ‘silence’ the gene, with the potential to cut many years from the conventional ‘conversion’ process. Over time, one could envision making most elite sorghums ‘impregnable’ to the Ma1 gene, such that most progeny of crosses between elite and exotic lines are immediately day-neutral in the F1. The nature of the gene and its native regulatory features may also suggest means by which one could exogenously induce short-day plants to flower (although this is less of a problem, in that simply covering with a trash can at night for 2-3 weeks is usually an adequate method).

Lead PI: Ismail Dweikat, University of Nebraska $39,000.00 Gene Discovery for Sorghum Responses to Nitrogen

Project Summary:

Sorghum (Sorghum bicolor L. Moench) is an important cereal crop for feed, food, and a biofuel uses. It is as input efficient, drought tolerant, and environmentally friendly crop. Nitrogen (N) and water availability are considered two of the major limiting factors in crop growth. Nitrogen fertilization accounts for about 40% of the total production cost in sorghum. In cereals, including sorghum, the nitrogen use efficiency (NUE) from fertilizer is approximately 33% of the amount applied. There is therefore extensive concern in relation to the N that is not used by the plant, which is lost by leaching of nitrate, denitrification from the soil, and loss of ammonia to the atmosphere, all of which can have deleterious environmental effects. To improve the potential of sorghum as a leading and cost effective bioenergy crop, the enhancement of NUE must be addressed. To this end, we have identified a sorghum line (SanChi San) that displays about 25% increase in NUE over other sorghum lines. As such, the overarching goal of this project is to employ complementary strategies to enhance the ability of grain sorghum to become an efficient nitrogen user. To achieve the project goal, we will pursue the following specific objectives:

Objective 1: Conduct quantitative trait loci (QTL) analysis and marker identification for nitrogen use efficiency (NUE) in a grain sorghum RIL population

Objective 2: Identify novel candidate genes for NUE using proteomic and gene expression profiling comparisons of high- and low- NUE RILs. Candidate genes will eventually be used for transgenic manipulation of NUE in grain and sweet sorghum.

This project will employ proteomics and gene expression profiling strategies to identify genes controlling NUE, one of the most complex and economically important traits in cereal crops. At the completion of the proposed work, we will have: 1) identified novel alleles in wild sorghum germplasm that are useful to improve both cultivated grain and sweet sorghum; 2) selected individual plants that exhibit high NUE within a breeding population on the basis of these markers

Lead PI: John J. Burke, USDA-ARS Lubbock $32,392.00 Identifying and developing new drought tolerant sorghum germplasm

Project Summary:

Post-flowering drought tolerance (the “stay-green” trait) is an essential trait for increasing the production of sorghum [Sorghum bicolor (L.) Moench] in increasingly variable climates. Previously, methodologies for identifying the nonsenescent (stay-green) trait required the right intensity of drought stress at the right developmental stage to visually evaluate lines in the field. Field-based evaluations of drought tolerance are notoriously difficult to manage, and often require growing lines in multiple locations across several years in order to acquire a meaningful assessment of the stay-green trait. Now, because of a new technique developed in my laboratory, we can readily identify stay-green lines by means of a 30-minute high temperature challenge to leaf tissue from pre-flowering well-watered sorghum and 30-minute room temperature recovery. Evaluation of ten known stay-green and senescent sorghum lines with this bioassay allowed us to separate the two classes of sorghum from well-watered pre-flowering plants. The stay-green lines can also be separated from senescent lines under well-watered greenhouse conditions from the boot-stage onward. This technology will greatly reduce the selection time needed to identify drought tolerant sorghum.

The proposed research will continue to use this new technology in a two pronged research approach to identify germplasm with improved drought tolerance. The first approach was to evaluate photoperiod sensitive lines of the Sudan Core Collection (Dahlberg et al., 2004) from the USDA sorghum collection for lines with the “stay-green signature” provided by this technique. Lines with Stay-green and non-stay green characteristics in the bioassay were identified. These lines will be re-evaluated in the coming year to ensure a reproducible phenotype. Lines from the Ethiopian sorghum collection will be evaluated in the coming year for the stay-green trait.. The second approach was to characterize mutants of BTx623 that we have isolated and identified as exhibiting the “stay-green signature” under field and greenhouse conditions. Existing mutants were confirmed and back-crossing initiated. Additional putative mutants were identified from a field screen and will be evaluated to ensure that a reproducible phenotype is observed. Both research avenues are providing new sources of drought tolerance that can be used to improve sorghum hybrids. Mutants of BTx623 that exhibit the stay-green trait can be moved directly into breeding programs to provide new more drought tolerant sorghum hybrids. Lines identified from the screening of the photoperiod sensitive lines can be moved into the sorghum conversion program to develop photoperiod insensitive lines, or used directly in tropical environments to move the stay-green trait into elite germplasm.

Lead PI: Tesfaye Tesso, Kansas State University $41,500 Study of genetic and physiological characteristics associated with improved nitrogen use efficiency and drought tolerance in sorghum

Project Summary:

Nitrogen is one of the essential mineral nutrients required for successful production of grain and biomass crops. Most agricultural soils contain low amount of nitrogen and hence require supplemental nitrogen applied in the form of fertilizer for optimal productivity. But almost all of the previous studies have shown that most crop plants utilize less than half of nitrogen added to the soil with the remaining nitrogen lost through leaching or denitrification, or incorporated into the organic fraction through immobilization. With the cost of chemical fertilizer increasing, growers feel the consequence of this lose more than ever. It is very important that solutions be sought to address this problem either through developing nutrient efficient genotypes to effectively utilize supplemental nitrogen added to the soil or through developing alternative crop and soil management schemes that will minimize the loss.

Results from earlier research have indicated that genotypes and management conditions can significantly influence nitrogen use efficiency in sorghum. Post flowering drought tolerant “stay-green” genotypes have been reported to have improved nitrogen use efficiency over senescent genotypes. Some plant morphological attributes such as leaf thickness and specific leaf weight have been shown to be positively related to nitrogen use efficiency. While such information are useful for better targeting the problem in future research, most of the results so far generated are based on a small set of entries with relatively narrow genetic backgrounds. Evaluation of larger set of genotypes representing an array of genetic backgrounds having contrasting characteristics for traits assumed to be related to nitrogen use efficiency may help generate more robust information.

In this study we plan to evaluate a range of sorghum genotypes including sources known for their reaction to pre and post flowering drought tolerance, stalk rot resistance and yield potential, including elite breeding lines and commercial hybrids. The genotypes will be evaluated in high and low yield and nitrogen loss potential environments under variable nutrient and watering regimes. Data will be collected on several plant and soil parameters at different times during the growth cycle. Nitrogen use efficiency of genotypes in all environments will be determined and related to plant morphological and physiological characteristics. Plant traits found as highly related to Nitrogen use efficiency may be pursued as target for genetic improvement of nitrogen use efficiency. Differences in plant nitrogen use will also be related to agronomic characteristics such as standability, stalk rot resistance and grain quality attributes including test weight grain fill duration, grain weight, protein content and starch structures.

Disease and Pest Research

Lead PI: Christopher Little, Kansas State University $20,000.00 Identifying genetic and structural sources of stalk rot resistance in diverse sorghum germplasm under dryland production

Project Summary:

In Kansas, Fusarium stalk rot and charcoal rot are the primary stalk rots that cause yield loss and lodging in sorghum. Fusarium stalk rots (caused by Fusarium spp. including F. thapsinum, F. proliferatum, and F. andiyazi) are important when high temperatures and drought stress occur during head initiation and caryopsis formation followed by exposure to cooler and wetter conditions. However, charcoal rot (caused by Macrophomina phaseolina) occurs during prolonged post-flowering drought stress and does not require a period of cooler temperatures or higher moisture in order to manifest itself. From 1994-2008, the mean actual grain sorghum yields in Kansas averaged 212 million bushels (MBu) per year and ranged from 143 to 368 MBu during this period. As early as 1996, Doug Jardine (Extension Row Crops Pathologist, KSU), noted that stalk rots (especially Fusarium stalk rot) cause 5-10% yield losses per year in Kansas and continued to note consistent disease. This suggests that attainable yields would have averaged 223 to 234 MBu during this period. Such yield impacts of both stalk rots are also seen in other sorghum producing states including Texas and Nebraska.

A goal of this project is to assess losses in sorghum seed weight and quality due to stalk rots in dryland production systems. This will be accomplished through the identification of drought-tolerant germplasm possessing acceptable end of season yield parameters and lodging resistance after stalk inoculations with Fusarium spp. and Macrophomina phaseolina after flowering. It is clear that resistance to Fusarium stalk rots and charcoal rot are genetically and mechanistically divergent; previous efforts have identified some dominant resistance to Fusarium stalk rots. However, responses to the various Fusarium pathogens (see above) differ greatly and inoculations with these needs to be tested in greater detail. Secondly, the best source of tolerance to stalk rot diseases and resultant lodging is a strong stalk. To assess structural resistance to stalk rots in diverse sorghum germplasm, stalk strength will be assessed at multiple plant developmental stages using a rind penetrometer. This is a hand-held instrument that measures the amount of force required to penetrate the rind of the sorghum stalk, and the amount of resistance associated with this force requirement is related to rind thickness and composition. Stalk strength will be further evaluated by obtaining crude fiber, cellulose, lignin, and silica measurements from stalk samples throughout the experiment. Additionally, a 300-line sorghum diversity panel will be screened to catalogue the diversity of stalk rot pathogens (with emphasis on Fusarium spp.) and stalk strengths will be acquired using rind penetrometry.

The control of stalk rot, especially through better understanding of pathogen biology and screening and enhancement of genetic material for use in breeding programs is an essential activity which will result in lodging resistant and increased yielding hybrids. In order to do this, interconnected strategies must be adopted: (1) identify germplasm with improved stalk strength and tolerance to pre-harvest lodging, and (2) identify germplasm with resistance (quantitative, partial, or complete) to the stalk rot pathogens, and (3) ensure that identified germplasm possesses post-flowering drought-tolerance and concomitant tolerance to charcoal rot.

Lead PI: Clint Magill, Texas AgriLife Extension Service/TAMUS $27,000.00 Potential Sources of Ergot Resistance

Project Summary:

The emergence of the disease ergot in the US over the past decade has created problems for both the sorghum seed industry and producers. Although Claviceps africana, the causal organism does not produce toxins like some ergots, infection does reduce yields and the syrupy honeydew that it produces can clog combines. Because it infects only unpollinated florets, the exposed stigmas of male sterile lines used for hybrid seed production make these ‘A’-lines’ especially vulnerable. Naturally there has been a scramble to identify cultivars that show genetic resistance to the disease, and while some prospects have been identified, most seem to rely on flowering traits that would not be compatible with hybrid production. Consequently, screening of a collection of 242 sorghum cultivars, that was specifically designed by an ICRISAT collaborator to contain as much variation in germplasm as possible is included as one component of this project. However the main thrust of this proposal is to evaluate prospects for creating or enhancing resistance to C. africana by manipulating host defense responses. Since some components of the normal host defense response might also inhibit successful pollen tube growth and fertilization, it seems plausible, or even likely, that host defense genes may not be activated in stigmas. If so, it may still be possible to genetically engineer stigmas to constitutively express proteins such as chitinases that would attack fungal but not pollen cell walls. However, if some or all of the host defense pathways are activated, it will be more useful to identify cultivars that are most effective in terms of rapidity or level of response, especially if different components predominate in different cultivars. In that case it should be possible to combine components by crossing selected parents and identifying progeny with enhanced host defense. The research for this aspect of the project will take advantage of quantitative PCR to examine the levels of mRNA for known defense response genes. In particular, genes that have been shown to be activated in sorghum leaves and glumes in responses to other pathogens will be targeted. Messenger RNA levels for defense genes with different modes of action will be measured in control stigmas and stigmas inoculated with ergot spores. Multiple cultivars, including A-lines and accessions such as ATx2752 that have shown a degree of tolerance will be included.

The investigators and collaborators have both the equipment and experience required for disease assessment and for the technically challenging aspects of mRNA quantification. The results of both components should help steer efforts to identify or create ergot resistant sorghum.

Lead PI: Norman Elliott, USDA-ARS Stillwater $28,000.00 Sequential Sampling and IPM Decision Aids for Headworm in Grain Sorghum

Project Summary:

The United States produces the more sorghum of any other nation, and most of that production is in Texas, Oklahoma, Kansas, and Nebraska. Sorghum headworm is an economically important insect pest of sorghum throughout United States often ranked 1st or 2nd in importance among the myriad of insects that feed on sorghum. Sampling for headworm in sorghum fields is currently accomplished by the beat bucket sampling technique with a fixed sample size. Fixed sample size sampling has two adverse characteristics. First, decisions on whether the economic threshold has been exceeded have variable and unknown statistical precision. Thus, a producer makes a treat/no treat decision with a generally unknown level of confidence as to whether the correct decision is being made or not. The main product of the proposed research will be a new, time efficient, sequential sampling technique for headworm in grain sorghum for use by producers, crop consultants, and IPM specialists in Texas, Oklahoma, and Kansas. The second contribution is an internet based tool for implementing sequential sampling in IPM decision-making. The proposed research project is highly relevant to the USCP’s mission because products of the research will “increase producer profitability” and “enhance the sorghum industry” by providing sampling tools to protect grain sorghum yields from a major insect pest. The project directly addresses the USCP goal to “Increase yields overall by 5% per year through 2015” through application of the specific USCP strategy to “Identify and target technologies and/or practices that solve specific insect and disease problems”.

Management

Lead PI: Michael Ottman, University of Arizona $24,168.00 Development of forage sorghum tissue testing for efficient fertilization

Project Summary:

Nitrogen fertilizer costs have fluctuated wildly in the past few years. Sorghum silage is an attractive crop because it requires less fertilizer than corn silage. However, fertilizer guidelines are not available for forage sorghum production in the desert southwest. In order to develop these guidelines, we propose to conduct a nitrogen fertilizer rate study in Maricopa, AZ. Nitrogen fertilizer will be applied to forage sorghum at 8 rates varying from 0 to 350 lbs N/acre in split applications during the season. The lower portion of the stem will be sampled six times during the growing season and analyzed for nitrate. In addition and new to the proposal this year, the whole plant and most recently developed leaf will be analyzed for total N. Preliminary post-plant nitrogen fertilizer guidelines will be developed based on lower stem nitrate, plant N, and leaf N.

Publishable guidelines can only be established with 2 or more years of data. The proposed research was funded in 2009 and this proposal represents the second year of work. The plant and leaf N analyses were not included in the 2009 proposal, but these analyses will be performed on the 2009 samples based on suggestions of the reviewers.

Lead PI: Kraig Roozeboom, Kansas State University $25,000 Update Publication on Growth, Development, and Nutrient Uptake of Sorghum

Project Summary:

Efficient management practices aimed at improving productivity and profitability for any crop require an adequate understanding of its growth, development, and nutrient uptake patterns. The most comprehensive publication on sorghum growth and development (How a Sorghum Plants Develops) has served scientists, students, extension agents, and producers over many decades and has been extensively cited in the literature. Significant changes in sorghum genetics and management practices and the need for high-quality electronic images make it necessary to update this important resource. This proposal is intended allow us to follow through with updating this publication with current hybrids and new, high-resolution electronic images for dissemination to producers, consultants, researchers, and extension agents.

This project was initiated in 2009 with the goal of generating developmental data and images for 2 grain sorghum and 2 forage sorghum hybrids. In 2009, we successfully tracked phenology, sampled for dry matter and nutrient partitioning, and photographed the two grain sorghum hybrids. Sample grinding and nutrient analysis is in process and will likely take much of the winter to complete. Two forage sorghum hybrids were planted in 2009 as well, but non-uniform stands made the initial planting unusable. A planter problem caused even worse stands in the second planting. As the season progressed, it became evident that sampling the 2 grain sorghum hybrids in a timely manner used all available resources anyway. The emphasis in the field in 2010 will be on the forage sorghum sampling. Grain sorghum plots will be planted for additional pictures to complement those taken in 2009 and for another year of tracking developmental stages. This second year also will be used to finish lab analysis, data summary, and development of the actual publication.

The new updated publication will be beneficial to people involved sorghum production, research, extension, and industry. Copies of this publication will be distributed to sorghum producers and researchers across the country. This publication will serve the mission of the United Sorghum Checkoff Program to increase productivity of sorghum through education.

Lead PI: David Mengel, Kansas State University $20,000 Enhancing sorghum yield and profitability through efficient nitrogen management

Project Summary:

Though assumed to be 50% when making nitrogen recommendations, the actual Nitrogen Use Efficiency/percent N recovery found in Kansas varies widely from a low of <40% to over 60%. Quantitative knowledge of the expected NUE from alternative N management strategies, or changes in NUE that could be expected by adopting different strategies under different production environments, would allow adjustment in N application rate and have a positive impact on sorghum yield and profitability. This project proposes to systematically obtain that information across a range of environments, and develop a framework to incorporate that NUE information into the Kansas N recommendation system.

Lead PI: Susan O’Shaughnessy, USDA-ARS Bushland $11,000.00 Investigating automatic irrigation scheduling and quantifying water use efficiency and yield for limited and fully irrigated and early and late maturing grain sorghum

Project Summary:

This proposal is submitted as a continuing research project for automatic irrigation scheduling of deficit irrigated grain sorghum and its impact on water use efficiency. Investigators collaborating on this project have high levels of expertise and experience in areas of irrigation engineering, soil science, plant physiology, automatic irrigation scheduling, crop water use measurement and estimation, agronomy, and sensor development. This proposal also represents collaboration between USDA-ARS and Texas AgriLife Extension Service for a multi-year research project. Progress from the study will be published in the Bushland USDA-ARS semi-annual newsletter (the “Wetting Front” product of the Soil & Water Management Research Unit), and a refereed journal. Agronomic progress and results will also be disseminated by Texas AgriLife Extension Service for outreach with local producers.

Sorghum is a highly adaptable forage and grain crop and is an important agricultural feedstock for dairies and ethanol production. In the Northern High Plains district of Texas, 40% of grain sorghum is irrigated, resulting in yields double those from dryland farming (Colaizzi et al., 2008). Improving crop productivity without significantly impacting the existing water supply and quality of the yield is becoming a major focus of consideration for producers to either maintain or improve their profitability. This research project will continue to investigate automatic irrigation scheduling based on two different types of thermal stress indices and two different varieties of grain sorghum using center pivot systems and LEPA irrigation. Crop canopy temperature measurements and microclimatological data will be made from sensors located on the pivot and in the field. Main effects of deficit irrigation treatments and manual and automatic methods will be analyzed against sorghum yields.

In cooperation with Texas AgriLife Extension Service, whenever possible, our field experiment will be incorporated as an onsite visit during a sorghum field day. Results will be incorporated into sorghum management Powerpoint presentations at local and regional Extension programs. Possible topics to be included in the field day include: the impacts of limited irrigation on sorghum development and yield, irrigation levels and water use efficiency, optimal thermal stress indexes for irrigation scheduling, and the benefits of irrigation technology on water conservation and profitability.

Lead PI: Calvin Trostle, Texas AgriLife Extension Service/TAMUS $19,705.00 Continue Expanded Grain Sorghum Hybrid Testing—West Texas

Project Summary:

This project is a renewal/refinement request of numerous objectives and sorghum test sites in West Texas that were initially funded by USCP in 2009. In particular, this includes regions of Texas that are underserved by Texas AgriLife, including the Rolling Plains and Concho Valley, where in each case no field testing on grain sorghum had occurred in recent memory and minimal Extension efforts were made. Continued hybrid testing efforts are also focused on the area around an all-sorghum ethanol plant in Hockley Co. This proposed work continues sorghum hybrid testing by diversifying planting dates (but with fewer hybrids—we believe that an additional planting date will increase chances of carrying at least one dryland test site per region to harvest) for the Vernon/Chillicothe area, Ballinger/San Angelo area, Lamesa, and Hockley Co. (We have discontinued our work in partnering for supplemental funding of Texas AgriLife Crop Testing hybrid sites as they will establish a new fee structure to reflect their limited resources and testing capability.) Furthermore, an objective requested by USCP and implemented in 2009, testing of maturation of late planted hybrids at Lubbock, will be continued. An agronomic component combining deep soil sampling with N & P fertility in a sorghum/cotton rotation is added for the Concho Valley. Finally, in lieu of the dearth of sorghum relevant, updated sorghum information available to sorghum producers in underserved regions like the northern Rolling Plains and the Concho Valley, project personnel will collaborate to develop an Extension workshop program in these and two additional sorghum regions. These workshops will serve as the impetus to compile and update relevant grain sorghum production information for producers. In addition, summarized data will be available annually on the Soil and Crops Variety Trials web site (http://varietytesting.tamu.edu).

New Uses and Utilization

Lead PI: Donghai Wang, Kansas State University $31,578.00 Protein Adhesives from Low-Cost Sorghum DDGS

Project Summary:

In the United States, annual demand for adhesives and resins exceeds 20 billion pounds. Currently, most adhesives used in the wood industry are petroleum-based, such as phenol-formaldehyde and urea-formaldehyde adhesives. Formaldehyde emissions cause many environmental and health issues. Development of biobased adhesives not only significant impact a >$100 billion industry sector, but also solve the environmental issues related volatile organic compounds (VOC) emission and reduce our relying on petroleum-based feedstocks with carbon reduction benefits. Currently, numbers of leading industries are seeking environmental friendly adhesives; however, the major challenge to their switching from petroleum-based to biobased feedstocks is the high cost of biobased feedstocks and enabling technologies to meet their requirements. The sorghum protein adhesives using low-cost DDGS will be one solution to industry. The cost effective processing approach of the adhesives using low cost feedstocks will allow industry to initiate commercialization of the technology developed from this research.

The long-term goal of this proposed research is to develop affordable, durable and biodegradable protein adhesives using low-cost sorghum DDGS to increase the profitability of sorghum industry and reduce VOC emission and reduce reliance on fossil feedstocks. The short-term goal is to establish the feasibility of an innovative technology to produce affordable and durable biobased protein adhesive using low-cost sorghum protein from DDGS, which have great potential to replace petroleum-based polymers such as formaldehyde-based adhesives. The research will focuses on 1) development of innovative technology for extraction of proteins from sorghum DDGS with high yield, high purity, and desirable functionality for industrial uses; 2) characterization of physical, chemical and structural properties of sorghum proteins from DDGS; and 3) evaluation of adhesion performance of sorghum protein and improve sorghum protein adhesion by chemical modification.

The proposed research will deliver the state-of-the-art technology for adding values to biofuel and food residues such as sorghum DDGS. This would help to sustain sorghum bio-industry as well the global economic development and improve environment. The success of this project will provide informative data and knowledge for large-scale production of biodegradable adhesives from sorghum protein with desirable properties. Success in the research program will result in a low-cost technology to produce affordable and durable biobased adhesive using low-cost DDGS. The results from this project will provide a platform technology to open up significant markets for utilization low-cost by-products from ethanol industry and give ample scope for renewable resources utilization, especially using low-cost by-product. Development of biobased adhesives could significantly impact a >$100 billion industry sector that currently relies on petroleum-based feedstock with their attendant environmental problems. Large market of plywood, particleboard, and coatings for construction and furniture represents huge demands for various adhesives. Our proposed research addresses the Mission of USCP of “USCP commits to effectively investing checkoff dollars to increase producer profitability and enhance the sorghum industry” and this research addresses the technical area of “development of new uses in bioenergy, foods, and health” described in the RFP.

2009 Research Projects

Bio Energy

Lead PI: Bill Rooney, Texas A&M -- $35,347 Establishing the Relationship between Forage Sorghum Composition and Bioenergy Composition Values

Project Summary:

Various agencies and industries have identified sorghum as the primary annual dedicated herbaceous bioenergy crop for second generation biofuel production in the U.S. While yield is a major factor measuring energy potential on a per acre basis, composition also influences the yield of bioenergy produced. Animal feeders have long known that forage sorghums differ in their feeding quality; hence they developed methods of measuring such quality that have been used for many years. Unfortunately, these estimates of forage quality do not relate well to the composition standards required bioenergy conversion. They tend to overestimate some components and underestimate others. To alleviate that problem, the initial biochemical composition analyses are being completed, which allows for the systematic comparison of forage composition with biochemical composition. The objective of this proposal is to compare and analyze a set of sorghum biomass samples using both techniques and to develop, if possible, an approach to effectively estimate biochemical composition from the existing forage quality data. This will allow us to utilize a significant and valuable existing resource to optimize sorghum composition for bioenergy production.

Breeding

Lead PI: Hays Experiment Station - $40,000 Development of sorghum germplasm with enhanced drought tolerance and higher grain yield

Project Summary:

Sorghum is predominately grown in harsh environments because it is one of the few crops that can be successfully cultivated under these conditions. Improving yield under these conditions will require the development of new germplasm that can withstand these unfavorable conditions. Drought, both pre- and post-flowering is the most common impediment to high yields. Pre-flowering drought limits grain yield by limiting the development of seeds while post-flowering drought leads to lodging and small kernels. In the absence of adding additional water, breeding for increased tolerance to water stress by studying processes linked to plant performance under stress and incorporating new genes is a proven way to increase yield. . In areas of sorghum production where the constraint of limited water is not severe, sorghum must compete with corn and soybean. To do this, sorghum yields must be increased. The utilization of exotic material may lead to new genetic systems that will add to grain yield. In addition, changing the planting management to more closely mimic that of corn needs to be investigated. Developing new germplasm sources that incorporate these traits and which can then be utilized by the seed industry to produce hybrids is essential to increased sorghum production.

Disease and Pest Research

Lead PI: Tom Isakeit, Texas AgriLife Extension -- $13,800 Integrated Management of Sorghum Downy Mildew in Texas

Project Summary:

Sorghum downy mildew (SDM), caused by the fungus Peronosclerospora sorghi, is emerging as a potential constraint to sorghum production in the Upper Gulf Coast counties of Texas. Initially, there was the emergence of a metalaxyl-resistant isolate in 2001 in Wharton County, which was followed by the emergence of a new metalaxyl-resistant pathotype that overcame some sources of host resistance in 2005. Experiments in Wharton county demonstrated a disease incidence of up to 24% in susceptible hybrids. The new pathotype has spread within Wharton County and in 2008, was found in Victoria County. Although there is currently research evaluating new sorghum germplasm and new fungicides for management of SDM, we are proposing to increase educational efforts to more intensively promote existing IPM (integrated pest management) practices for managing this disease in the short term (i.e. the next few years) and integrating new germplasm or fungicides as they become available into a control program over a longer period of time. We propose to conduct extensive surveys for SDM in an eight-county area of the Upper Gulf Coast. We will map locations of SDM and identify the pathotype and metalaxyl sensitivity. We will conduct demonstration trials of hybrids with resistance to the prevailing pathotype in several counties, assessing both disease severity and yield, in comparison with susceptible yields. We will also perform trials demonstrating the effectiveness of crop rotation. We will promote these trials with field days and county meetings, as well as publish the results. Educational bulletins will be developed and disseminated via mailings and the internet. The efforts will be coordinated by a plant pathologist, but will rely heavily on the contributions of a multi-disciplinary team of agronomists and entomologists, since factors in addition to disease resistance will affect the yield of a hybrid. The integration of efforts will be at a regional level through extension specialists and IPM agents, as well as at a county level through county agents. This area of Texas accounts for 8% of the yield for the state, but represents a value of the crop of $67 million (2008 statistics: 13.5 million bushels @ $5/bu). A widespread presence of SDM in this area could conceivably result in a yield loss of millions of dollars, which our proposed educational efforts would avert. Our efforts could be transferred to other sorghum production areas of the United States, where SDM could become a problem in the future.

Lead PI: Kassim Al-Khatib, KSU – $41,400 Optimization and Education Program for Herbicide Resistant Technology in Sorghum

Project Summary:

Field research and educational programs will be conducted during 2009 at six states that represent significant part of the sorghum producing areas in the US. The objectives of the project are to optimize herbicide resistant technology, educate growers how to use the technology effectively, and develop stewardship program to manage the technology. Acetolactate synthase (ALS) and Acetyl COA carboxylase (ACC) resistant sorghum will be planted in separate studies at 15 sites in Kansas, Oklahoma, Texas, Nebraska, Colorado, and South Dakota during 2009. Accent and Assure II will be applied at 0.67 and 7 oz/A, respectively. In addition, Accent and Assure II will be applied in combination with selected herbicides. Sorghum injury ratings will be determined 1, 2, 4, and 8 weeks after postemergence treatments. Sorghum plant height will be determined at flowering stage. Grain will be harvested mechanically from the center two rows of each plot and weighed then destroyed. Data will be analyzed using analysis of variance and regression analyses as appropriate. The proposed research will develop necessary data that will develop a cost effective and environmentally sound weed control practice in grain sorghum. The ALS and ACCase technologies will add new tools for weed management in sorghum. These technologies are extremely important because it can be used as postemergence treatment to control weeds including grasses that escape the preemergence treatment. Information form this research will be transferred to sorghum growers through field days, tours, extension bulletins, and seminar presentations by the principal investigators and extension personnel.

Lead PI: Brent Bean, Texas AgriLife Extension--$18,000, Evaluation of saflufenacil and pyrasulfotole herbicides for crop tolerance and wee control in sorghum

Project Summary:

Due to the lack of registration of new herbicides in sorghum over the last 20+ years, producers must rely on a limited selection of chemicals for effective, economical weed control in sorghum. Weed control is always stated in surveys as one of the major concerns producers have in growing sorghum. For this reason, one of the goals of the USCP is to have new weed and grass control options utilized on 50% of the sorghum acres by 2015. This study will evaluate two new herbicides, saflufenacil and pyrasulfotole, for use in sorghum in the High Plains region. It is anticipated that each will be registered in 2011. Trials will conducted to 1) evaluate broadleaf weed and grass control efficacy, 2) crop tolerance as affected by soil texture, 3) appropriate application rates and timings, 4) tank mix partners, and 5)economics of weed control systems using these new herbicides. Information gained will be communicated to producers and consultants through presentations, publications, and media.

Genomics and Biotechnology

Lead PI: Zhanguo Xin--$52,200, Establishing a pedigreed sorghum mutation library-A cmmunity resource for sorghum improvement

Project Summary:

The proposal focuses on the development of an Annotated Individually-pedigreed Mutagenized Sorghum (AIMS) library consisting of 6,400 independent mutant families. With the sorghum genome sequence completed, the challenge is now to harness the genome sequence information to accelerate sorghum improvement for new uses. Mutants are a very powerful tool for relating sorghum (and other) genes to their functions – the visual effects of disrupting a gene quickly inform us about what the gene does in its normal state. One of the major obstacles for sorghum genomic studies is the lack of a systematic mutant population to investigate the functions of sorghum genes and for selection of traits that can be directly used to improve sorghum for new uses, such as foods, feed, health, and bioenergy. As a crop with highly-productive C₄ photosynthesis, as well as excellent tolerance to high temperature, drought, and low soil fertility, sorghum is likely to become increasingly important in the future. Expansion into new markets through adaptation of sorghum to new uses is needed to sustain growth and profitability. To fulfill the need for functional genomic studies toward developing sorghum for new uses, we propose to establish a mutant library in the inbred line BTx623. This inbred line was used for the genome sequence, and therefore offers an advantage because mutations can be easily determined through comparison with the reference sequence. BTx623 seeds will be mutagenized by the chemical ethyl methane sulfonate (EMS), which is known to induce a broad spectrum of mutations. The mutagenized seeds will be propagated to the third generation (M₃) through single-seed-descent to guarantee that each mutant family is derived from an independent mutation event. Seeds will be bulked thereafter for public distribution. Phenotypes will be carefully evaluated at M₃ generation. The mutant plots will be open to public and private sorghum researchers through field days and individual arrangements to select mutants for their respective needs and priorities. All phenotype information will be captured in an online searchable database to benefit sorghum research and foster collaborations. Genomic DNA from each plant that is used to produce the M₃ seeds for the mutant library will be prepared. The DNA will be deposited in a central lab for identification of mutants for specific sorghum genes that can serve as potential candidates for sorghum improvement. Coupled with high throughput mutation detection in specific genes, mutagenesis has been used to breed soybean and peanut with high quality oil and low allergenic activity, and to produce high digestible starch in wheat and maize. Our pilot project displayed many potential useful mutations, such as brown midrib mutants, monoculm, large panicle, staygreen, and cold tolerance. Availability of a mutant library with an adequate number of families will accelerate sorghum functional genomic studies and aid the breeding efforts to adapt sorghum into new uses.

Lead PI: John Burke, USDA-ARS Lubbock--$32,292, Identifying and developing new drought tolerant sorghum germplasm

Project Summary:

The proposed research will use this new technology in a two pronged research approach to identify germplasm with improved drought tolerance. The first approach will evaluate photoperiod sensitive lines of the Sudan Core Collection (Dahlberg et al., 2004) from the USDA sorghum collection for lines with the “stay-green signature” provided by this technique. The second approach will be to characterize mutants of BTx623 that we have isolated and identified as exhibiting the “stay-green signature” under field and greenhouse conditions. Both research avenues should provide new sources of drought tolerance that can be used to improve sorghum hybrids. Mutants of BTx623 that exhibit the stay-green trait can be moved directly into breeding programs to provide new more drought tolerant sorghum hybrids. Lines identified from the screening of the photoperiod sensitive lines can be moved into the sorghum conversion program to develop photoperiod insensitive lines, or used directly in tropical environments to move the stay-green trait into elite germplasm.

Lead PI: Andy Patterson, University of Georgia--$32,500, Identification of Mal, the gene that hinders utilization of exotic sorghum germplasm

Project Summary:

Critical problem. The single greatest hindrance to utilization of exotic germplasm in improvement of sorghum for temperate agriculture is that the vast majority of such germplasm flowers only at short daylength, as a result of the Ma1 gene conferring photoperiod sensitivity. Much effort in ‘conversion’ of exotic sorghums to day-neutral forms by a lengthy and tedious crossing program has rendered about 700 exotic sorghums more useful in breeding programs, however this remains only a tiny sampling of extant sorghum diversity.

Research approach. Over more than a decade of research, we have ‘mapped’ the short-day flowering trait to a small region of the genome, sequenced the genome, scrutinized the ~30,000 genes in the sequence, and narrowed the list of candidates to about 400. Herein, we seek to narrow the list of candidates to a much smaller number and further test those showing especially great promise based on their phenotypic effects in botanical model plants, by utilizing a ‘diversity panel’ of 384 genotypes that broadly samples worldwide sorghum diversity, provided by our cooperators H. Upadhyaya (germplasm curator), and C. T Hash (sorghum breeder) at ICRISAT. We expect the outcome to be the demonstration that different ‘versions’ (alleles) of one particular gene are closely correlated with differences in flowering time among members of the panel, indicating that the gene is Ma1. In addition, a fringe benefit will be to set the stage for the identification of the nearby dw2 gene that accounts for much of the tall stature of exotic sorghums.

Potential benefits/impact. Identification of the specific gene responsible for short-day flowering would empower the use of a variety of mechanisms to ‘silence’ the gene, with the potential to cut many years from the conventional ‘conversion’ process. Over time, one could envision making most elite sorghums ‘impregnable’ to the Ma1 gene, such that most progeny of crosses between elite and exotic lines are immediately day-neutral in the F1. The nature of the gene and its native regulatory features may also suggest means by which one could exogenously induce short-day plants to flower (although this is less of a problem, in that simply covering with a trash can at night for 2-3 weeks is usually an adequate method).

Lead PI: Gloria Burow, USDA-ARS Lubbock--$84,000(2-year project), Accelerated Development and Deployment of Cold Tolerant Sorghum Germplasm Through the Practival Application of Biotechnology Resources

Project Summary:

Sorghum is well known for its drought tolerance and overall adaptation to high temperature. At the other end of the temperature spectrum, sorghum generally lacks cold tolerance and is vulnerable to cool temperature, specifically during stand establishment in early season planting from April to May in most areas of the US sorghum belt. Stand establishment and early season vigor of sorghum is adversely affected by air and soil temperatures below 60ºF (15°C) during germination, emergence and early seedling growth. Cold tolerance is recognized as a crucial factor for increasing yields, both allowing farmers to capitalize on early season moisture and also that fuller season varieties with higher yield potential may be developed. Fortunately, excellent sources of cold tolerance have been identified within the sorghum gene pool, and steps have been taken to begin the process of developing the tools needed to bring these genetic resources to market.

To support the need for cold tolerant germplasm, the sorghum improvement project at the USDA-ARS –Lubbock, TX initiated and pursued research efforts aimed at the identification of sources of cold tolerance and development of genetic resources for the transfer of cold tolerance traits to U.S.-adapted sorghum. Furthermore, genomic tools such as DNA markers have been created in the program, to facilitate the application of marker technology to the overall improvement of sorghum. This proposed project focuses on the utilization of an advanced Recombinant Inbred Line (RIL) population specifically designed to be used as a tool for understanding cold tolerance, through a synergistic collaboration between public programs (USDA-ARS, KSU) and a private company (Advanta U.S., Hereford TX). We will carry out a comprehensive evaluation of cold tolerance across three locations within the U.S. grain sorghum belt and characterize a sizeable number of F6 lines to pinpoint genetic regions associated with cold tolerance. The identification of Quantitative Trait Loci (QTL) will enable the rapid development of cold tolerant sorghum hybrids through the use of Marker Assisted Selection (MAS). To better understand the inheritance of this trait and to determine the most effective means of hybrid development, we will also create F1 hybrids between sterile versions of Chinese sources of cold tolerance and elite US A/B lines. This will provide estimates of the performance of these traits in hybrid combination and assess the importance of seed parent vs. pollinator in cold tolerance. Finally, the project will disseminate marker technology to sorghum researchers by providing ready-to-use DNA markers that cover the whole genome.

This proposal will address the issue of sorghum cold tolerance in an integrated fashion that facilitates the analysis and characterization at both the whole plant and molecular level. We will deliver a platform for gene identification and DNA marker tools that will facilitate the breeding of both grain and forage sorghum with enhanced cold tolerance. The project is envisioned to directly benefit sorghum producers and promote the core values of the sorghum check off board thru research through the establishment of public-private sector partnerships.

Lead PI: Gebisa Ejeta, Purdue University--$157,978 (3-year project), Marker Assisted Introgression of Cold Tolerance into Elite Sorghum Inbred Lines

Project Summary:

Cool temperatures during the early growing season are a major limitation to growing sorghum (Sorghum bicolor (L.) Moench) in the northern mid-west regions of the United States, and other temperate areas. Sorghum originated in tropical and subtropical regions of Africa. Sorghums from these primary centers of crop origin of tropical north-east Africa, lack this trait. China is the only place in the world where sorghum evolved under temperate condition. Perhaps as a result, many sorghum landraces introduced from China exhibit higher emergence and greater seedling vigor when grown under cool conditions than typical US-bred lines. Unfortunately, however, Chinese sorghums also possess several undesirable agronomic traits. Introgression of seedling cold-tolerance genes from these landraces into elite inbred lines requires careful manipulation to avoid genetic drag and, such a feat could potentially be facilitated by marker-assisted selection (MAS). However, empirical studies that have demonstrated the value of MAS for quantitatively inherited agronomic traits in field crops have been few. In our laboratory, we recently completed a successful step-wise study where we first observed segregation of QTL for early-season cold tolerance in a recombinant inbred (RI) population one parent of which was a cold-tolerant Chinese line, Shan Qui Red (SQR). We followed that observation by the further identification of three SSR markers each representing a QTL for cold tolerance. And finally, we were then able to validate the association between the presence of these markers and the phenotypic expression of seedling cold tolerance in two newly created segregating populations with SQR as a donor parent for the cold tolerance trait. In the current study, we propose to introgress these three markers into selected inbred lines of sorghum, both pollinators and seed parents, to generate isogenic hybrids with and without the SSR markers as a proof of concept to further verify the efficacy of these markers as selective tools for marker-based selection for seedling cold tolerance in sorghum. This is a necessary step before broader use of these markers that we identified is recommended for commercial application of sorghum breeding for early-season cold tolerance in sorghum.

Lead PI: Andy Paterson, University of Georgia $48,180 Association genetics of sorghum drought tolerance

Project Summary:

This proposal is focused on supporting increases in the yield and yield stability of sorghum through research, specifically on the topic of development and deployment of water management and water use efficiency. The decision to grow sorghum is frequently based on its drought tolerance. The importance of drought tolerance in agriculture is likely to grow—agriculture uses 69% of the world’s available water supply, and 46% of available water in the USA. Many parts of the world, including some parts of the USA, face “water scarce” conditions in the future. The development of drought-resistant crops by conventional breeding has been hampered by low heritability, and by large ‘genotype x environment’ interactions. Conventional sorghum breeding has only utilized a small subset of the available germplasm—we hypothesize that a substantial degree of phenotypic variation in responses to drought exists and remains among a broad sampling of sorghum genotypes.
The proposed activities build upon a detailed physiological and agronomic characterization of a ‘diversity panel’ of 384 geneotypes that broadly samples worldwide sorghum diversity, let by our cooperators H. Upadhyaya (germplasm curator), v. Vadez (plant physiologist), and C. T. Hash (sorghum breeder) at ICRISAT. Numerouse –omics approaches offer the means to develop testable hypotheses about possible relationships between specific genes or gene families and drought response. Our work will identify specific genes, DNA markers, and possibly even nucleotides, that are diagnostic of particular drought responses.
These DNA markers may accelerate progress in sorghum improvement through either marker-assisted selection or through identification of specific genes that make singularly large contributions to sorghum drought tolerance. Because the diversity panel to be studied broadly samples worldwide sorghum diversity, molecular-level results are expected to have a very broad relevance to the sorghum gene pool generally, and phenotypic results are expected to identify a broad sampling of drought tolerant germplasm, different subsets of which are likely to be adaptable to different regions. The benefits of using such germplasm lines might be determined quickly, by their evaluation in hybrid combinations with wiedly-used inbreds already adapted to respective target regions.

Lead PI: James Mahan, USDA-ARS Lubbock--$42,504 (2-year project), Use of canopy temperature to optimize water use and irrigation management in sorghum

Project Summary:

The combination of declining water resources and increasing costs for irrigation have resulted in renewed interest in the optimization of water use in sorghum. New water-efficient germplasm and improved irrigation management can both contribute to economical water use. The development of tools for the identification of improved sorghum hybrids and irrigation scheduling methods tailored to sorghum will provide new opportunities for sorghum as a profitable crop under limiting water conditions.

Regardless of the germplasm used by the producer, profitability will be improved by appropriate irrigation management. Some current irrigation methods are not well-suited for use in many sorghum production settings. This project will provide the basis for implementation of the BIOTIC irrigation scheduling in sorghum across a range of irrigation intensities.

While new sorghum germplasm is essential for production under limited irrigation, the identification of germplasm for improved water use is limited by the lack of suitable methods for monitoring water use among large numbers of sorghum hybrids. A newly developed infrared thermometry system used in this study, coupled with new insights into the relationship between plant temperature and water use, will provide a new tool for germplasm identification.

Over a 20-year period scientists from the Plant Stress and Germplasm Development Research Unit in Lubbock TX have carried out extensive research into the use of plant temperature for the management of crop irrigation. A number of crop species have been studied though the bulk of the studies have utilized cotton. Insight into the relationship between crop canopy temperature and water status resulted in an irrigation management protocol referred to as BIOTIC that has been licensed by Smartfield Inc (Smartfield.com). Smartfield is marketing a device based upon our BIOTIC protocol under the name Smartcrop. Smartfield’s hardware and software provides a conduit for the direct transfer of the results of this study into the production agricultural community.

A “spin-off” product of BIOTIC research is a simple to use low-cost wireless infrared thermometry system that has greatly simplified the use of infrared thermometry in agricultural settings and is compatible with production systems. This new temperature monitoring system coupled with our previously developed BIOTIC irrigation scheduling provides the basis for the use of canopy temperature for the identification promising germplasm for production under limited irrigation.

The current commercial status of the technology coupled with the researchers’ previous experience in technology transfer provide a pathway to rapid adoption of the approaches developed in this project.

Lead PI: Susan O'Shaughnessy, USDA-ARS Bushland--$13,500, Investigating automatic irrigation scheduling and quantifying water use efficiency for limited and fully irrigated grain sorghum using LEPA irrigation

Project Summary:

This proposal is submitted by a group of investigators who amongst them have high levels of expertise and experience in areas of irrigation engineering, soil science, automatic irrigation scheduling, crop water use measurement and estimation, agronomy, and sensor development. This proposal also represents collaboration between two entities, USDA-ARS and Texas AgriLife Extension Services for a two year research project. Progress from the study will be published in the Bushland USDA-ARS bi-annual news letter (the “Wetting Front” product of the Soil & Water Management Research Unit), and a refereed journal. Agronomic progress and results will also be disseminated by Texas AgriLife Extension Service for outreach with local producers.

Sorghum is an important forage and grain crop and is widely used as agricultural feedstock for ethanol production. In the Northern High Plains district of Texas, 40% of grain sorghum is irrigated, resulting in yields double to those from dryland farming (Colaizzi et al., 2008). Improving crop productivity without significantly impacting the existing water supply is becoming a major focus of consideration for producers to either maintain or improve their profitability. This research project will investigate automatic irrigation scheduling based on a temperature stress index. Crop canopy temperature measurements will be made from wireless sensors mounted on a six-span center pivot arm. Yield responses will be analyzed across fully randomized plots (four manual irrigation treatments- 80%, 55%, 30%, and 0% of evapotranspiration (ET) (calculated from Penman Monteith Equation and retrieved from the Texas High Plains ET network) and their automatic analogs and three replications, blocked by control type (manual or automatic) and analyzed using Proc Mixed statistical models.

In cooperation with Texas AgriLife Extension Service, our field experiment will be incorporated as an onsite visit during a sorghum field day. Possible topics to be included in the field day include: the impacts of limited irrigation on sorghum development and productivity, irrigation levels and water use efficiency, optimal thermal stress indexes for irrigation scheduling, and the impact of irrigation technology on water conservation and profitability.

Management

Lead PI: Kraig Roozeboom, KSU $26,590 Update Publication on Growth, Development, and Nutrient Uptake of Sorghum

Project Summary:

To develop efficient management practices aimed at improving productivity and profitability for any crop, it is essential to understand its growth, development, and nutrient uptake patterns. At the present time, the most comprehensive publication on sorghum growth and development was originally published 30 years ago (How a Sorghum Plants Develops) at Kansas State University with minor updates in 1993 (Vanderlip, 1993). This has served scientists, students, extension agents, and producers over many decades and has been extensively cited in the literature. However, significant changes in sorghum genetics and management practices make it necessary to update this important resource. In addition, the images depicting growth stages are not available in high-quality electronic form, limiting their dissemination and use in presentations and publications. Through this proposal we intend to update this publication with current hybrids and develop new, high-resolution electronic images for dissemination to producers, consultants, researchers, and extension agents. We will update this information for both grain sorghum and forage sorghum hybrids. Two grain sorghum hybrids (medium early and medium late) and two forage sorghum hybrids (standard and photoperiod sensitive) will be grown under currently recommended crop management practices. Destructive samples will be taken at 10-day intervals throughout the growing season for determination of dry matter partitioning (leaves, stems, seed and roots) and nutrient concentration in each component. This data will be used to develop growth curves and nutrient uptake (N, P, and K) curves and yield over the entire growing period of the crop. Similarly, at each development stage, images will be taken to illustrate key growth stages of both grain and forage sorghum. Overall, the new updated publication will be beneficial to people involved sorghum production, research, extension, and industry. Copies of this publication will be distributed to sorghum producers and researchers across the country. This publication will serve the mission of the United Sorghum Checkoff Program to increase productivity of sorghum through education.

Lead PI: Fred Miller, MMR Genetics, LLC--$115,000 (multi-year project), Re-Instatement of the Sorghum Conversion Program

Project Summary:

This project focuses on the conversion of valuable tropical Sorghum bicolor (L.) Monech germplasm to short stature, early flowering cultivars with an emphasis on improving access to major heterotic groups and the subsequent increased grain yield that could be obtained through new superior higher yielding sorghum hybrids. The overall goal of this project is to continue the process of converting useful, potentially higher yielding alien sorghum germplasm, while maintaining an emphasis on expediting the timeline to release converted materials through modifications to the classical breeding scheme and implementing the use of molecular markers. The products from this proposal will be improved sorghum germplasm, new breeding methodologies for rapid conversion of tropical accessions, and the potential to release new germplasm from superior heterotic groups resulting in a marked increase in hybrid grain yields.

Lead PI: Calvin Trostle, Texas AgriLife Extension -- $28,104 Expand Grain Sorghum Hybrid Testing—West Texas

Project Summary:

This project seeks funding, both primary and supplemental, to expand support for new West Texas grain sorghum hybrid trial testing as well as bolster existing program in the Texas AgriLife Research Crop Testing program. Areas targeted for new test sites include: dryland—Perryton, on-farm Levelland (near the ethanol plant using 100% grain sorghum), Vernon, Lamesa, and on-farm Ballinger/San Angelo; irrigated, Perryton and on-farm Levelland. Existing dryland test sites in the current official crop testing program will receive additional support due to the 2007 initiative to re-start dryland sorghum hybrid testing in West Texas whereby companies were offered three test sites for the price of one (Bushland, Lubbock, & Clovis, NM). Additional funding was anticipated for these sites through the state sorghum association, but this did not materialize hence these sites are greatly underfunded. Depending on the arrangement a minimum of eight hybrids chosen by Texas AgriLife Extension will be tested at on-farm sites, and sites affiliated with official Crop Testing work include as many as 30 hybrids. Results will be at the forefront of Extension producer education programs for grain sorghum in West Texas.

Lead PI: Mike Ottman, University of Arizona--$18,849, Development of forage sorghum tissue testing for efficient fertilization

Project Summary:

Nitrogen fertilizer costs have fluctuated wildly in the past few years. Sorghum silage is an attractive crop because it requires less fertilizer than corn silage. However, fertilizer guidelines are not available for forage sorghum production in the desert southwest. In order develop these guidelines, we propose to conduct a nitrogen fertilizer rate study in Maricopa, AZ. Nitrogen fertilizer will be applied to forage sorghum at 6 rates varying from 0 to 300 lbs N/acre in split applications during the season. The lower portion of the stem will be sampled six times during the season and analyzed for nitrate. Preliminary post-plant nitrogen fertilizer guidelines based on lower stem nitrate will be developed. Publishable guidelines can only be established with 2 or more years of data.

Lead PI: Mike Ottman, University--$24,140, Development of forage sorghum tissue testing for efficient fertilization

Project Summary:

Nitrogen fertilizer costs have fluctuated wildly in the past few years. Sorghum silage is an attractive crop because it requires less fertilizer than corn silage. However, fertilizer guidelines are not available for forage sorghum production in the desert southwest. In order develop these guidelines, we propose to conduct a nitrogen fertilizer rate study in Maricopa, AZ. Nitrogen fertilizer will be applied to forage sorghum at 6 rates varying from 0 to 300 lbs N/acre in split applications during the season. The lower portion of the stem will be sampled six times during the season and analyzed for nitrate. Preliminary post-plant nitrogen fertilizer guidelines based on lower stem nitrate will be developed. Publishable guidelines can only be established with 2 or more years of data.

New Uses and Utilization

Lead PI: Curt Well, University of Nebraska -- $48,700 Identification of the ‘prebiotic’ fraction of grain sorghum lipid extract

Project Summary:

Grain sorghum is a rich source of phytochemicals that could potentially benefit human health. Our group has shown that Grain Sorghum Lipid extract (GSL) included in the diet significantly improved the non-HDL/HDL cholesterol equilibrium of Syrian hamsters, a recognized animal model with cholesterol metabolism of humans (Carr et al., 2005). Furthermore, we have identified that GSL stimulates putative health promoting bacteria in the gastrointestinal tract of hamsters, and that alterations within the gut bacteria were strongly linked to improvements in cholesterol metabolism (Martínez et al., 2009). These studies provide evidence that modulation of the gut microbiota-host metabolic interrelationship using GSL extract has the potential to improve cholesterol homeostasis, which has relevance for cardiovascular health. Cardiovascular disease (CVD) is a major problem in the United States and other developed countries in part due to unhealthy diet choices. Better diet choices including functional foods (i.e. fresh or processed foods claiming to contain nutraceuticals or have a health-promoting and/or disease-preventing property beyond the basic function of supplying nutrients), nutraceuticals (i.e. extracts of foods claiming to have a medicinal effect on human health) and prebiotics (i.e. non-digestible functional foods or food ingredients that stimulate the growth and/or activity of bacteria in the digestive system for the health of the body) offer the potential to reduce CVD-related disorders and save millions of dollars spent on associated health care costs. Our previous studies clearly demonstrate the great potential of GSL extract as a functional food ingredient to prevent CVD.
The research outlined in this proposal seeks to determine which fraction of GSL exerts a cholesterol lowering effect in hamsters and the mechanisms underlying this effect. This study will therefore provide important knowledge for the utilization of GSL extract as a functional food ingredient to improve human health. Once the role of GSL extract is better understood, markets for functional foods containing grain sorghum could open in not only developed countries but also in developing countries that have traditionally consumed sorghum-based food products. The proposed lipid research will complement the concurrently proposed starch digestion studies at Kansas State, cross-linking and sorghum-phenolic-based food preparation studies at the USDA-ARS GMPRC, and anti-oxidants and phenolics studies at Texas A&M. Together, results from the studies at the four research entities will provide more comprehensive knowledge on nutritional and health benefits of grain sorghum in the diet.

Lead PI: Lloyd Rooney, Texas A&M University & Mark Haub, KSU--$102,426, Developing Healthy Foods from Special Sorghums

Project Summary:

This collaborative project consists of a carefully chosen team of scientists with the skills and experience required to provide fundamental and practical information on the unique health benefits that sorghum contains. Sorghum has a wide array of phytochemicals ranging from condensed tannins to flavones, flavanones, and rare the 3-deoxyanthocyanins that have significant potential use in foods and extracts.

Members of the team are highly experienced in starch, protein and their interactions in foods. We will concentrate on obtaining additional information on the apparent reduced digestibility of heat-modified sorghum. The condensed tannins reduce feed efficiency when fed to livestock but that is a positive for reduced-calorie diets for humans. We will confirm our recent data in which tannins heated with starch and sorghum endosperm reduced starch digestibility significantly. Thus, we can produce low- calorie foods that are suitable for weight-conscious humans and for type 2 diabetics. For the first time, we will obtain data on the glycemic index of these sorghum products.

Some sorghum varieties have very high levels of polyphenols, which include condensed tannins while others have high levels of 3-deoxyanthocyanins, which are rarely found in nature. The condensed tannins of sorghum have very high antioxidant power and significantly decrease the feed efficiency of sorghums for livestock, which means that they may have excellent properties for producing foods for diabetics and low caloric diets. We believe that tannins react with protein and starch to reduce hydrolysis and produce resistant starch. Therefore, this project proposes to measure the glycemic index (GI) of cooked products with and without tannins and other phytochemicals. Rats will be fed sorghum bran and whole grains to see if fat deposition is decreased by polyphenols.

Sorghum components for use in reducing inflammation and cancer risk will be evaluated with in vitro tests. Foods containing tannins and other phytochemicals will be analyzed to determine their anti-inflammatory properties. The use of different sorghums in processed foods is increasing significantly. The team of scientists represented in the project can provide excellent information on the various aspects of sorghum for use in health foods. The flour of sorghum behaves differently than corn, which we will attempt to understand in this project. Our efforts so far have established that special sorghums have outstanding properties for food utilization but we need significantly more information as proposed in this project.

Progress is being made in breeding to improve the properties of some of the most interesting sorghums to produce reliable levels of varieties with unique properties. Thus, sorghum breeders and others are important members of the team. Thus, we have the opportunity to improve the overall concept of sorghum into a positive image of “Hey it’s a Great FOOD GRAIN!” We have information in the pipeline that can be used to develop several brochures and fact sheets on sorghums related to whole grains, celiac foods, phytochemicals, and natural unique food colorants that can be developed during the first year.

Lead PI: Dongai Wang--$60,174, Protein Adhesives from Low-Cost Sorghum DDGS

Project Summary:

Lead PI: Dave Mengel, KSU--$10,000, Enhancing Sorghum Yield and Profitability through Efficient Nitrogen Management

Project Summary:

Nitrogen fertilizer represents a significant investment for many sorghum growers. In Kansas growers will normally invest $15 to $60 per acre in nitrogen each year. Recent work shows that the current preplant N recommendations overstimate N needs by 26 pounds N per acre, if growers use a preplant soil test. Without soil tests that over recommendation can easily double. However, less than 10% of the sorghum fields grown in Kansas use current profile N tests as a base for N recommendations.

Sorghum is also normally grown in high risk environments. One too available to growers to reduce the risk and enhance return on their fertilizer investments is to delay N application until mid-season, when a better assessment of yield potential and N need can be made. By using crop sensors mid-season, together with well placed N fertilized reference strips, much more accurate N recommendations can be made.

The efficiency with which applied N is recovered by the sorghum crop, NUE, also varies dramatically. Past work in Kansas has shown N recovery to vary from <30 to >60%. This significantly impacts both yield and the N application rate required to reach maximum yield.

This project proposes to conduct a series of field experiments to address these three issues. Classical N response data will be collected to assist in the development of more effective N rate recommendations, both traditional preplant soil tests based and sensor based. In addition a NUE rate adjustment will be developed using both results found in the literature and new field data which will allow quantifying differences in NUE found between various N management practices.

The potential benefits to farmers will be much more accurate N fertilizer recommendations, reduced N application costs and potentially higher yields. This could result in a potential increase in net returns of $5 to $20 per acre from a combination of reduced N cost and/or higher yield.

Latest News

February 01, 2012

Mexican Market Offers Opportunity for South Texas...

With the La Nina weather pattern expected to continue, the South Plains of Texas once again...

Events Calendar

Nebraska Sorghum Profitiability Seminars
February 02

International U.S. Grains Council Meeting
February 13