Keeping American Agriculture Competitive
...While Ending World Hunger

Helping Americans and our Neighbors Prosper

Animal Research

  Influence of Sire Breed and Creep Feed on Meat Goat Doe-Kid Performance

  Characterization of Small-Breed Cattle for Small-Scale Beef Production 

  Goat Meat Consumption in Tennessee: Factors Influencing Market Expansion for Traditional and Non- Traditional 
  Consumers

  Strategies for Improving Growth, Production Performance and Feed Efficiency in Poultry

 
Plant Research

  Genetic Assessments of Cotton Chromosome Substitution Lines Identified for Nutritional Quality Seed Traits

  Bacterial Wilt of Cucurbits: Molecular Probe into the Genomes of Erwinia tracheiphila, the Wilting Pathogen of Melon,
  Cucumber and Squash

  Development of Integrated Organic Management System for Vegetables in Tennessee

  Germplasm Enhancement in Soybean Using Chemical Mutagenesis

  A Study on the Epigenetic Mechanism for Abiotic Stress Tolerance Traits in Plants

  C4 Gene Manipulation and Climate Change Adaptation in Grain Amaranth


Influence of Sire Breed and Creep Feed on Meat Goat Doe-Kid Performance
Dr. Richard Browning
Meat goats represent an emerging livestock class offering U.S. farmers a new option for on-farm income. Demand for chevon is increasing in the U.S. because of increasing ethnic diversity. The U.S. has been a net importer of chevon since 1991. Chevon (goat meat) imports by the US increased over 500% from 142 to 10,166 metric tons from 1987 to 2007 (FAO, 2010). During the same period, the US meat goat inventory grew from 0.42 to 2.60 million head (USDA, 2009). Domestic production continues to fall short of demand. Chevon production in the US was 21,500 metric tons in 2007 (FAO, 2010). The meat goat inventory in Tennessee and eight bordering states represent 25% of the total U.S. meat goat inventory in 2012 and 6 of the 10 largest state meat goat inventories (USDA, 2013). The average meat goat farm in the US had 21 head in the latest census (USDA, 2009). Opportunities exist for these small-scale and limited-resource farm operators to produce some of the chevon currently imported. At least half of the US demand for chevon is filled by imports. In the first half of 2014, an equivalent of nearly 600,000 goats on a 15 kg carcass weight basis were imported to meet US demand. A heightened ability of the US industry to profitably satisfy the growing demand for chevon presents opportunities for rural communities to obtain additional sources of revenue. This is espcially true of small scale, limited resource operators that meat goat production is more suited to as opposed to other red meat livestock sectors. As a healthy red meat alternative, chevon demand will likely continue to surge as a larger segment of the US population becomes familiar with the product, providing greater opportunities for this emerging animal industry sector provided ample research is conducted to reduce the risk of inefficient production practices. To address the issue of increasing the supply of domestic chevon to meet consumer demand, this project will look at simple genetic and nutritional management approaches to increase yield in meat goat herds without compromising monetary return to the producer. On the genetic side, a relatively novel sire breed (Savannah) will be compared to established breeds (Kiko and Spanish) to determine if the choice of sire breed will alter the growth of market kids to weaning. Nutritionally, a well known but relatively underevaluated practice within the goat industry of creep feeding will be characterized to determine if significant improvements in weight gain can be expected and if the extra cost of gain would be prohibitive to increasing profitability for operators. The overreaching aim is to determine if particular management decisions would have a positive or negative impact on animal performance and enterprise economics.

Characterization of Small-Breed Cattle for Small-Scale Beef Production
Dr. Richard Browning
Most beef cow-calf enterprises are small-scale operations with just under 25 head of cattle on average. Economic estimates  range from 200 to 500 cows as the inventory needed to have an economically viable beef cattle enterprise. Herds under 50 are  the least economically sustainable. Typical of other states in the region, most TN beef cattle operations are small in scale. The  average farm size in TN is 65 ha. It would take 243 to 362 ha to run 300 typical commercial beef cows. The average weight of  the US beef cow has increased in the last 30 years. Cows tend to become less efficient with increasing mature size. Larger  mature cow weights also result in increased carcass weights. Portion sizes for beef within the USDA guidelines are limited with  the total daily recommendations for meat and protein alternatives to be 142 to 198 g. Increasing carcass sizes can pose issues  with fabrication to produce acceptable whole muscle retail cuts that meet USDA dietary recommendations. A non-traditional  animal industry that has emerged among limited-resource, small-scale operators is meat goat production. Advantages include  animal carrying capacity per unit of land, ease of management because of small mature size, and high efficiency of female  reproductive output. However, many commercial meat goat operations struggle to realize profits because of unstructured  marketing and the scarcity of FDA-approved goat pharmaceuticals for effective health management.  Initiatives to incentivize new farms among the young, the retired, and veterans will create increased interests to explore and  enter livestock production in small-scale systems. It is possible that a smaller breed of beef cattle could contribute to animal  production by addressing the issues addressed above. The Dexter is an established, unique breed with small stature. Dexter  cattle originated on the British Isles in the early 1800s and were first imported to the US in the early 1900s. The mature weight  of Dexter cows is less than 340 kg. The small size would seem to make Dexter cattle suited for the small acreage, part-time  farms. More cows could be carried per unit of land with more calves to sell. Smaller cows may be more efficient performers and  easier to manage within a well-supported, traditional industry.  The aim of the project is to determine if small-breed cattle could provide some advantages to low acreage managers interested  in raising grazing livestock in general or beef cattle specifically. Dexter cows will be managed in a low-input grazing system with  planned pure breeding and crossbreeding to characterize this breed for cow-calf production values from breeding to weaning.  The Dexter management system will run parallel to an established meat goat breeding system to compare efficiencies of female  production. With increased interest in grass-finish cattle in the South, Dexter will be crossed with a small heat-tolerant Sanga  beef breed (Mashona) to assess benefits gained from crossbreeding. Tall fescue is the predominant southern grass, so heat  tolerance would be beneficial in grass finishing systems where heat intolerance because of fescue toxicosis would be a  problem. Findings of this project will be shared with both the academic community at professional meetings and current and  potential ruminant livestock managers at industry events. If Dexter cattle can improve the scaling problems associated  traditional small-scale beef cattle systems, the economic outlook for this major segment of the beef industry and southern  agriculture would be enhanced. Grass-finished beef is an emerging niche segment of the beef sector. Dexter cattle may provide  a unique contribution to this market because of their small size and likely early maturity.

Goat Meat Consumption in Tennessee: Factors Influencing Market Expansion for Traditional and Non- Traditional Consumers
Dr. Enefiok Ekanem
Tennessee is the second largest producer of goats in the United States. The industry brings millions of dollars into the state's economy every year. Many goat producers in Tennessee are small and consequently face challenges in marketing their products, securing sufficient capital, credit, other resources and accessing potential markets. In spite of these challenges, the demand for goat meat continues to increase from traditional and nontraditional consumers. This project will collect and analyze data that provides a better understanding of consumers of goat meat by examining factors that influence their consumption decisions. The meat goat industry presents great opportunities to enhance the incomes of small farmers and rural residents of Tennessee through strong demand and consumption.
The objectives of proposed study are to: (1) Review existing relevant literature on demand, supply and consumption of goat meat in Tennessee, (2) Identify current markets where goat meat is sold in Tennessee, (3) Identify and analyze factors that influence consumption of goat meat in Tennessee, and (4) Explore the economic implication of expanding goat meat consumption to non-traditional goat meat consumers in Tennessee.
Secondary data will be collected from published sources. Focus group meetings, face-to-face interviews, telephone and mail questionnaire surveys will be used in collecting primary data for proposed study. A random sample of consumers from selected metropolitan statistical areas will be used for the study areas in Tennessee. Data collected will be analyzed using Microsoft Excel and the Statistical Package for the Social Sciences. Data collected throughout the proposed study will be analyzed, interpreted and used in deriving policy implications. This project will target: producers, consumers, marketers (specialty stores, retail stores, super markets, farmers' markets), extension agents, community leaders, stake holders, students, researchers, educators, and others. Expected Project Output will include: enhanced consumer knowledge about goat meat which will result in increases in the purchase of goat meat to generate additional income for meat goat producers, Increased producer knowledge of market size, discover new goat meat sale to existing markets, Documentation of the number of grocery store managers with increase knowledge of specific attributes, Estimated percentage of market managers with increased knowledge of what the consumers want in goat meat . Estimate percentage of public (marketers/researchers/educators and producers) with increased knowledge of what consumers want from stores that sell goat meat and Estimate the number of individuals interested in buying goat meat.

Strategies for Improving Growth, Production Performance and Feed Efficiency in Poultry
Dr. Samuel Nahashon
The aim of the proposed work is to enhance growth, production performance, feed efficiency and profitability of poultry, especially chickens and guinea fowl. An additional goal is to continue developing the guinea fowl as alternative poultry for small scale and limited resource farmers in Tennessee. The optimum requirement for the amino acids methionine and cysteine by the French and Pearl grey guinea fowl are lacking. Also, the minimum amounts of nutrients, especially the essential amino acids that sufficiently drive metabolic processes in poultry are not well established. The requirement of these nutrients for optimum growth and production performance of poultry will be evaluated. The use of direct-fed microbials such as Lactobacillus acidophilus to improve efficiency of nutrient utilization in chickens and guinea fowl will also be evaluated. In completely randomized design, French and Pearl grey guinea fowl and broiler chickens will be assigned to floor pens and subjected to dietary treatments. Dose response experiments with varying dietary levels of each individual nutrient will be conducted from hatch to eight weeks of age. The optimum levels of these nutrients and the effectiveness of direct fed microbials will be determined by growth performance, carcass characteristics, and assay of metabolic indices and gene expression of the experimental birds. Additional cDNA libraries of key organs such as the liver, pancreas and hypothalamus of the guinea fowl will also be constructed and screened to facilitate the identification of economically important metabolic pathways that will guide design of optimum feeding regimens. Findings from this research will be published in the Journal of Poultry Science and optimum levels of these nutrients will be recommended to guinea fowl and traditional poultry producers.

Genetic Assessments of Cotton Chromosome Substitution Lines Identified for Nutritional Quality Seed Traits
Dr. Ahmad Aziz
Cotton is the fourth leading crop in the US and is grown in more than 100 countries. Also it is one of the largest crops in State of Tennessee with annual production of over 500,000 bales (480 lbs). Cotton is a cash crop for over 20 million farmers in developing countries especially due to its substantial amount of cottonseed which has high economic value. However, its defense chemical 'gossypol' which is located all over in plant reduces the nutritive value of cottonseed product. There are considerable variations in gossypol contents within the same species, and Gossypium hirsutum (Upland cotton) as well as G. barbadense varieties have been found to contain only 0.42% and 0.73% free gossypol in seed, respectively. Interspecific chromosome substitution (CS) F1 stocks and backcross-derived chromosome substitution lines of Upland cotton (n = 26) have been created with alien chromosomes from G. barbadense (n = 26) line 3-79 which are nearly isogenic to the common parent TM-1 for 25 chromosome pairs, as well as to each other, for 24 chromosome pairs. The comparative analysis of such unique genetic materials greatly empowers the detection of novel mechanisms by specific alien chromosomes associated with traits like seed composition and nutritional quality. Through molecular analyses of isolated pollen grains from above mentioned hypoaneuploid lines this project will explore the adaptation of innovative markers' procedures on desired cotton types. Thus by providing effective and universal single gamete genotyping approach, this research will be very valuable to cotton breeding community in Tennessee, Southern Region and the Nation.

Bacterial Wilt of Cucurbits: Molecular Probe into the Genomes of Erwinia tracheiphila, the Wilting Pathogen of Melon, Cucumber and Squash
Dr. Charles Dumenyo
This is a project to study the biology of Erwinia tracheiphila (Et), an economically important bacterial plant pathogen. Bacterial wilt of cucurbits is caused by Et, which is transmitted by the striped cucumber beetle (Acalymma vittata) and spotted cucumber beetle (Diabrotica undecimpunctata howardi). Cucumber wilt is one of the most destructive diseases of cucurbits in 27 eastern US states. The bacteria overwinter in the beetles' digestive tract and are inoculated into young plants in the insect frass during feeding. Susceptibility varies among cucurbit species but infected plants ultimately die. In the past, the disease received limited research attention; but recent work has resulted in genetic characterization of strains and availability of draft genomes of several strains from different host species, including Cucurbita pepo (squash), Cucumis sativus (cucumber), and Cucumis melo (melon). Our overall research goal is to understand the genetics of pathogenesis of the bacterial wilt disease. We propose to 1, Do comparative analysis of draft genomic sequences of strains of cucumber, melon and squash subspecies of Et and to identify potential pathogenicity and virulence factors; 2, Construct saturation GFP-Tagged Transposon Tn5 mutant library of Et; 3, screen mutants in the host plants for a collection of mutants in host-inducible and host-repressible genes; and 4, clone the candidate virulence genes and investigate their role in causing the bacterial wilt disease. This project will enable us for the first time to start identifying the key genetic loci in the pathogenesis of this pathogen and create the foundation for development of a clear understanding of the mechanism(s) of pathogenesis of bacterial wilt. By identifying the key genetic players, we hope to gain insight into possible manipulations of the host or pathogen to reduce the incidence and associated loses due to bacterial wilt disease.

Development of Integrated Organic Management System for Vegetables in Tennessee 
Dr. Dilip Nandwani
Pesticide-free and quality vegetables are one of the great concerns and the so called modern cultivation techniques of  vegetables rely on petroleum based synthetic fertilizers and pesticides. To obtain higher yields the use of fertilizers and  pesticides is being increased many folds by farmers. As a result, contaminated products are grown by farmers which cause  different ailment instead of supplementing necessary nutrients in the diets of consumers. Therefore, consumers increasingly  prefer organically grown vegetables. Small-scale farmers operating under organic management systems can utilize non-  intensive inputs for crop production; however, such sources are limited. The proposal covers research, extension and education  components and main objective is to The long-term goal of 3 year project is to conduct cultivar evaluations in selected  vegetables (eggplant, peppers and tomato) that are best suited to organic production in Tennessee and economic benefits.  Within this context, the proposal addresses the following topical areas presented in the program guidelines, 1) Conduct cultivar  trials in selected vegetables (eggplants, peppers and tomato) that are best suited for organic management system; 2) Evaluate  potentials of grafting technology on the growth, yield potential, and disease resistance in tomato; 3) Evaluate economic  benefits/costs and identify risks associated with organic production of selected vegetables. The project proposes to disseminate  research-generated results in organic farming to incorporate into existing Extension Agent trainings and other agricultural  advisors, and a multi-dimensional Extension program for growers, and other agriculture professionals. The project target  growers in Southern States, minority and limited-resource farmers and conduct training workshops for trainers and  stakeholders. This includes developing and transfer of information on a national level regarding best organic cultural practices that improves yield and, quality of organic produce.

Germplasm Enhancement in Soybean Using Chemical Mutagenesis
Dr. Ali Taheri
Genetic variation is one of the necessities in plant breeding. This variation can be expanded by screening collections of soybean landraces and its related wild species from around the world. It is also possible to generate such genetic variation through induced mutation. The objective of this study is developing an mutagenic soybean population using recently released cultivar "JTN-5203" adapted to the state of Tennessee. This population will also be screened for herbicide tolerance mutants which then allows farmers to grow herbicide resistant soybeans without paying the premium price for such seeds developed by private companies.

A Study on the Epigenetic Mechanism for Abiotic Stress Tolerance Traits in Plants
Dr. Suping Zhou
Agriculture, especially the sector of crop production, is highly vulnerable to prolonged heat and cold temperatures, as well as drought, particularly when these events occur during key developmental stages. According to the NOAA's National Climatic Data Center, the winter of 2013-2014 was among the coldest on record in the Midwest and the driest and warmest in the Southwest (http://www.weather.com/news/winter-ncdc-state-climate-report-2013-2014-20140313). In August 2014, several counties are under drought conditions in the State of Tennessee, leaving farmers with more than 40% loss of major crops such as corn and soybean. Developing strategies to improve the tolerance of plants to these stresses will make significant contribution to sustainable agricultural development and food security at regional, national and international levels. Two mechanisms are used by plants to develop tolerance to stress factors. The first one is based on genetic makeup where tolerance is encoded by discrete genes. The second mechanism is by changing gene expression patterns without changes in the genome makeup. Epigenetic modification occurs through the second mechanism, which involves alteration of specific chromatin regions to allow or repress transcription of particular genes, thus regulating expression of certain sets of genes in response to environmental stimuli.
It has long been known that plants can acclimate to stress conditions and become more tolerant when the next round of similar stresses occur. Furthermore, the parental plants can pass on the acquired tolerance to offspring generations. Growing evidences have proved that epigenetics plays a very important role in the creation and sustaining of plant phenotypic plasticity. Panicum halli is a perennial C4 warm season plant species. These plants grow through the same schedule of different growth seasons in successive years throughout their life time. These plants are the ideal genetic materials for studying how and if the stress conditions experienced in the previous season will affect plant performance in the coming year. Additionally, P. halli plants produce plenty of fertile seeds; therefore those traits can also be tracked using seed-propagated plants. This project aims to address the following issues: the epigenetic reprogramming during transition from vegetative to reproductive phases; and the epigenetic processes occurring in tissues of actively root-tips and leaf blade under reciprocal water and temperature stresses compared to optimal growth conditions for plants derived from seeds or branches regenerated from stock plants. The final goal is to provide insight into factors responsible for regulating stress tolerance traits that are inherited via seeds or genome imprinting in stock plants.

C4 Gene Manipulation and Climate Change Adaptation in Grain Amaranth 
Dr. Matthew Blair
The rapid change in climate will require the selection for photosynthetic efficiency of the crops which is a pre-requisite best utilization of the C4 photosynthesis systems. This is what we plan to achieve with amaranth in the first part of this program. We do not plan to make a large number of crosses without first screening a large number of parents because of the short/term nature of the initial project (3 years). We will use Amaranth as a pre-existing C4 photosynthesis control in the families of dicotyledonous plants to see if this species is going to be adapted to climate change stresses of drought and higher heat,  perhaps replacing other crops that will become less suitable to the climate. We plan to make three inter/specific crosses in the amaranths to test the possibility of geneflow in this genus. We have in our present collection ornamental and grain amaranths.  We will search for naturally occurring herbicide resistance in pigweed to see if we can understand the inheritance of this trait and whether it comes at a cost in terms of photosynthetic efficiency.

 

 








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