News Article | May 2, 2017
IMAGE: In a recent study, researchers with the University of Tennessee Institute of Agriculture found the overall health of honey bees improved in the presence of agricultural production, despite the increased... view more JACKSON, Tenn. - While recent media reports have condemned a commonly used agricultural pesticide as detrimental to honey bee health, scientists with the University of Tennessee Institute of Agriculture have found that the overall health of honey bee hives actually improves in the presence of agricultural production. The study, "Agricultural Landscape and Pesticide Effects on Honey Bee Biological Traits" which was published in a recent issue of the Journal of Economic Entomology, evaluated the impacts of row-crop agriculture, including the traditional use of pesticides, on honey bee health. Results indicated that hive health was positively correlated to the presence of agriculture. According to the study, colonies in a non-agricultural area struggled to find adequate food resources and produced fewer offspring. "We're not saying that pesticides are not a factor in honeybee health. There were a few events during the season where insecticide applications caused the death of some foraging bees," says Mohamed Alburaki, lead author and post-doctoral fellow with the University of Tennessee Department of Entomology and Plant Pathology (EPP). "However, our study suggests that the benefits of better nutrition sources and nectar yields found in agricultural areas outweigh the risks of exposure to agricultural pesticides." Alburaki and fellow researchers established experimental apiaries in multiple locations in western Tennessee ranging from non-agricultural to intense agricultural production. Over the course of a year, colonies were monitored for performance and productivity by measuring colony weight, brood production and colony thermoregulation. Colony thermoregulation, or the ability to maintain an optimal temperature within a hive, is an important factor in brood development and the health of the resulting adult bees. According to the study, hives located in areas with high to moderate agricultural vegetation grew faster and larger than those in low or non-agricultural areas. Researchers suggest the greater population sizes enabled better colony thermoregulation in these hives, as well. Meanwhile, bees located in a non-agricultural environment were challenged to find food. Although fewer pesticide contaminants were reported in these areas, the landscape did not provide sustainable forage. In fact, during the observations, two colonies in the non-agricultural areas collapsed due to starvation. Disruptions and fluctuations in brood rearing were also more notable in a non-agricultural environment. Interestingly, brood production was highest in the location that exhibited a more evenly distributed mix of agricultural production, forests and urban activity. "One possible explanation for this finding could be the elevated urban activity in this location," says Alburaki. "Ornamental plantings around homes or businesses, or backyard gardens are examples of urban activity that increase the diversity of pollen in an area. Greater pollen diversity has been credited with enhancing colony development." Researchers also evaluated trapped pollen from each colony for pesticide residues. Low concentrations of fungicides, herbicides and insecticides were identified, but at levels well below the lethal dose for honey bees. Imidacloprid was the only neonicotinoid detected, also at sub-lethal levels. Agricultural pesticides, particularly neonicotinoids, are considered by some to be a key factor in declining honeybee populations. The UTIA study found that higher exposure to pesticides in agricultural environments did not result in measurable impacts on colony productivity. "We train agricultural producers on careful selection and conscientious application of pesticides to reduce bee exposure," says Scott Stewart, Integrated Pest Management Specialist with UT Extension, "but it's becoming more clear that the influences of varroa mite and food availability are more important factors in honey bee health than agricultural pesticides." This study was supported in part by the U.S. Department of Agriculture's Agricultural Research Service Pest Management Program. Through its mission of research, teaching and extension, the University of Tennessee Institute of Agriculture touches lives and provides Real. Life. Solutions. ag.tennessee.edu
News Article | April 21, 2017
KNOXVILLE, Tenn. - A group of students at the University of Tennessee Institute of Agriculture are among the best in the nation when it comes to knowledge of consumer dairy products. UTIA's Dairy Products Evaluation Team won first place at the 95th Collegiate Dairy Products Evaluation contest, held in mid-April in Madison, Wisconsin. Two of the student contestants, Michael Luethke, from Knoxville, and Katie Magee of Buffalo, New York, won the top undergraduate and graduate student awards, respectively. UTIA was tops among 14 participating teams, representing universities from across the country and one from France. It's the first time UTIA has won the top honor. Previously the team's highest finish was second place. The students judged six types of products -- milk, cottage cheese, vanilla ice cream, butter, cheddar cheese and yogurt -- evaluating eight samples of each item. The samples were prejudged by industry officials and coach judges were assigned to each product type. The students with scores most closely matching those of the official judges were declared the winners. The top three students in each product category were recognized, along with the top 10 students in the All Product category. The students are in UTIA's College of Agricultural Sciences and Natural Resources (CASNR) and its Food Science Department. Michael Luethke, a junior, was named the overall winner, and also placed first in cottage cheese and second in the milk categories. Rand Clapp, also from Knoxville, finished fifth overall, and Kindal Tatum of Murfreesboro finished seventh. Other team members who served as alternates and made the trip were undergraduates Bailey Brown from Jackson, Michael Lawrence from Perry County, and Quint Gasque from Kingston. Food science graduate student Katie Magee of Buffalo, New York, finished first in the graduate competition, placing first in cottage cheese, second in yogurt and third in cottage cheese. The team was coached by Charles White, adjunct professor of food science. Trent Kerley, a senior in food science, served as an assistant coach. "We can all be proud of the 2017 UTIA team," says White. "They worked hard, learned a lot and competed for four-and-a-half hours in a tough competition with the top teams in the country. Michael, Rand, Kindal and Katie are truly national champions." Travel expenses were paid by the Wisconsin Cheesemakers Association and the Tennessee Dairy Products Association. In addition, the Department of Food Science received $500 for being the top team. Through its mission of research, teaching and extension, the University of Tennessee Institute of Agriculture (UTIA) touches lives and provides Real. Life. Solutions. ag.tennessee.edu.
News Article | February 15, 2017
JACKSON, Tenn. - The Weed Science Society of America (WSSA) awarded the title of Outstanding Paper in Weed Technology to researchers from the University of Tennessee Institute of Agriculture. Matthew Wiggins, a recent Ph.D. graduate of UT's College of Agricultural Sciences and Natural Resources and Robert Hayes and Larry Steckel, both professors with UT's Department of Plant Sciences, co-authored the paper. "Evaluating Cover Crops and Herbicides for Glyphosate Resistant Palmer Amaranth Control in Cotton" appeared in Weed Technology in April 2016. The research evaluated four cover crops (cereal rye, crimson clover, hairy vetch and winter wheat) plus combinations of one grass and one legume followed by pre-emergence applications of fluometuron or acetochlor. The study showed that combinations of grass and legume cover crops accumulated the most biomass and reduced Palmer amaranth emergence by half compared to non-cover-treated areas. However, by 28 days after application, the cereal rye and wheat cover crops provided the best Palmer amaranth control. Herbicide-resistant weeds are a significant threat to agronomic crop production across the globe. Besides lost yields, Steckel estimates the costs of additional management can run from $35 - $100 per acre, depending on the crop. Integrating cultural practices, like cover crops, in weed management programs has been a central theme in UTIA weed science research for the past decade as scientists search for solutions to herbicide resistance. The Outstanding Paper award was presented February 6, 2017, during WSSA's annual meeting in Tucson, Arizona. "We're proud to honor true innovators who are making a significant mark on weed science through their commitment to research, education and teaching," said Janis McFarland, 2017 annual meeting program chair and incoming president of WSSA. The study was conducted at the West Tennessee AgResearch and Education Center in Jackson, Tennessee, and was partially funded by Cotton Incorporated through the Tennessee Cotton State Support Committee. Through its mission of research, teaching and extension, the University of Tennessee Institute of Agriculture touches lives and provides Real. Life. Solutions. ag.tennessee.edu
Agency: NSF | Branch: Continuing grant | Program: | Phase: | Award Amount: 189.97K | Year: 2012
The family Tachinidae contains nearly 10,000 described species of beneficial parasitic flies. As enemies of other insects, particularly herbivores, tachinids are important regulators of host populations in natural and agricultural ecosystems. They help in the natural control of numerous pest insects and have been effectively used in biological control of invasive pests. Despite their diversity and ecological importance, we know little about their interactions with hosts and how these have developed over time. The taxonomic difficulty and lack of a robust classification of tachinids has hindered both basic and applied research. The goals of this project are to reconstruct relationships among groups of tachinid flies using molecular and traditional methods and then use these results to produce a stable classification and to understand patterns of host-use and other life history traits. Another key goal is to broadly distribute taxonomic and biological information on tachinids to researchers and practitioners.
Tachinidae are the most important group of insect parasitoids outside of the wasps. A sound grasp of their history and a reliable taxonomic infrastructure are necessary to understand their roles as enemies, the evolution of their diverse attack strategies, and the causes of their rapid and rampant diversification. Such an understanding can guide the selection of the most effective tachinid biological control agents in agricultural and forest systems and limit the potential negative impacts upon non-targets. It will also inform broad issues in biology such as biogeography, ecological specialization, and the causes of adaptive diversification.
Agency: NSF | Branch: Standard Grant | Program: | Phase: | Award Amount: 234.15K | Year: 2016
Animals have limited life spans, and mortality is a common occurrence in terrestrial ecosystems. What happens in nature to the body of an animal after it dies? From an ecological perspective, a decomposing animal creates a localized pulse (hot spot) of nutrient-rich organic matter, fertilizing the soil below. Following death of an animal, the environment may be inoculated with microorganisms from the animals microbiome. Very little is understood about the ultimate fate of these nutrients and microbes - how much is retained in soil, recycled, or released into the atmosphere? These questions are important in terms of understanding how nutrients are produced and consumed in ecosystems, and evaluating the importance of carrion inputs across larger scales, following massive die-offs, for example. The focus of this study will be to determine the impact of decomposing animal carcasses on nitrogen (N) levels in soil. As a result, this research will contribute to our understanding of terrestrial nutrient fluxes, and will inform or expand existing models through the inclusion of carcass-derived inputs. This research will provide foundational knowledge about a natural decomposition process and the abiotic and biotic controls on nutrient recycling. This knowledge has potential applications for agriculture (livestock mortality disposal) and forensic science (time since death estimations). This project will also provide interdisciplinary training for a postdoctoral scholar in microbial ecology, soil biogeochemistry, forensic anthropology, molecular biology, and bioinformatics and will support and undergraduate trainee and the development of new curriculum on soil and environmental science for Tennessee 4-H programs.
This research will provide a comprehensive evaluation of N flux in carcass decomposition hotpots. Preliminary research shows that microbial communities in soils below a decomposing carcass include both native soil taxa and introduced taxa from the carcass or insects that visit the carcass. These communities change in both composition and function, shifting to more anaerobic metabolic strategies over time. The objective of this research is to determine the fate of N in carcass decomposition hotspots, and elucidate how abiotic (temperature and oxygen) and biotic (decomposer community composition) factors control the fate of N. The objective will be met using a combination of lab mesocosms and field decomposition experiments with carcasses, manipulating abiotic and biotic controls and documenting the effects on N pools (nitrate, ammonia, nitrous oxide) and fluxes (nitrification and denitrification rates). Decomposer microbial communities will be examined using functional gene expression of N cycling genes and sequencing. This will reveal the types of microbes involved in decomposition and the mechanisms by which they are transforming nutrients. Ultimately this research will provide an understanding of the postmortem fate of vertebrate nutrients in terrestrial ecosystems.
Agency: NSF | Branch: Continuing grant | Program: | Phase: | Award Amount: 222.74K | Year: 2011
Bacterial pathogens are diverse and important enemies of plants. In agriculture, these pathogens cause significant destruction of crops and necessitate costly applications of antibiotics. How is it that wild plants are able to resist infection by these same bacteria? If the resistance mechanisms of wild plants can be identified, they can be used to improve the resistance of crops. Towards this goal, this research team has discovered that some wild collected plants of Arabidopsis thaliana are dramatically more resistant to infection by the virulent bacterial pathogen, Pseudomonas syringae pv. tomato DC3000. The focus of the current project is to understand how elevated resistance in these plants is accomplished. For this purpose, the researchers use a powerful new approach, genome-wide association mapping, combined with mining of microarray data on gene expression, to identify focal candidate genes. RNAi knockdown lines will be created for these focal genes in the Stewart Lab and characterized in the Traw Lab for defects in plant resistance. In addition, plants lacking functional copies of these genes will be complemented with resistance allele candidates in both labs and tested in the Traw Lab to determine whether resistance is restored to those lines. Finally, given suspected roles of several candidates in membrane transport, broad and focused metabolite screening will be conducted by the Traw Lab using a subset of the experimental lines. One of the novel candidate genes is involved in the downstream response to abscisic acid. Allelic variation at that locus may therefore help explain how this bacterial pathogen is able to hijack the abscisic acid pathway in some plants. Thus, the project will provide strong insights into the mechanisms of natural plant resistance to bacteria. The findings are likely to contribute to the improvement of crop yields and reduction of exogenous antibiotic use in agriculture. The research may also contribute to improved treatment of bacterial diseases in humans. The project will advance the training of two postdocs and a graduate student, and will be used to create a series of laboratories that can be used in the teaching of introductory biology.
Agency: NSF | Branch: Continuing grant | Program: | Phase: Physiolg Mechansms&Biomechancs | Award Amount: 151.04K | Year: 2015
Plant cell walls contain lignocellulosic compounds that are difficult to degrade, such as xylan, cellulose, hemicellulose, and pectin. However, insect herbivores are capable of degrading these compounds and using the simpler compounds derived from the degradation processes for energy. While early work assumed that the source of the catalyst enzymes involved in the biochemical breakdown of lignocellulosic compounds (i.e., plant cell wall degradation enzymes, PCWDE) in insects was gut-resident symbiotic bacteria, recent work has shown that PCWDE produced by the cells of the insect gut are more important than previously realized. The goal of this research is to examine the diversity of PCWDE in two major lower insect lineages using a combination of functional genomics and biochemical tests. This basic research will improve understanding about the physiological mechanisms of insect digestion and may yield novel insights about insect control methods, biofuel industry improvements, and other industrial applications. This work will provide the opportunity for undergraduate, high school and graduate students to gain experience in cutting edge functional genomics, and insect physiology and biochemistry. Museum exhibits will be produced to educate the public about the importance of wood feeding insects. These exhibits will be presented at the University of California David Bohart Museum of Entomology and several other science museums across California and Tennessee.
Preliminary work revealed that Phasmids (walking sticks) and Thysanurans (silverfish and firebrats) have strikingly high numbers of PCWDE, that these genes show compartment specific expression within the gut, and are effective at degrading plant cell wall compounds. This project will identify the full complement of PCWDE present in the focal species (6 Phasmids and 3 Thysanurans) and compare the activity and expression levels of them in the digestive systems of these insects. Using heterologous expression, the researchers will characterize the activity of the most active enzymes in these systems. The researchers will also analyze how patterns of gene expression correlate with the physical attributes of the gut, which vary greatly between the two focal insect orders. The ultimate goal is to describe the variation in physiological compartmentalization of the digestive system and determine how it works synergistically with a diversity of differentially-expressed enzymes to maximize digestion of lignocellulosic compounds. Findings from this research will be published in peer-reviewed journals, and presented at regional and national scientific meetings.
Agency: NSF | Branch: Standard Grant | Program: | Phase: Enviro Health & Safety of Nano | Award Amount: 299.98K | Year: 2014
PI: Henry, Theodore B.
Proposal Number: 1435874
Institution: University of Tennessee Institute of Agriculture
Title: Effects of ingestion of manufactured nanoparticles on endogenous microbiota and pathogen resistance in rainbow trout
The objective of this proposal is to understand changes induced in the gut microbial community and on the host responses by nanoparticles (NPs). The overall hypothesis is that ingestion of nanomaterials, especially those that have anti-microbial properties, will change the microbiome (the community of microorganisms that share the body space) of trout resulting in adverse health outcomes. The investigators plan to investigate the changes in the microbiome resulting from the NP challenges, hypothesizing that these changes would lead to immunosuppression and increased opportunity for pathogen infection. The hypothesis will be tested with a bacterial pathogen challenge. The results of this investigation will provide new insights into the impact of NPs on the gut microbiome, which will have relevance not just for trout, but for humans and other organisms as well, since these fundamental host-microbiome interactions are conserved across all vertebrates. The data obtained from the proposed investigations can also be helpful for both industry and regulators as industry formulates new NPs with lower toxicity or regulators look to reduce exposure of humans and wildlife to NPs. The proposal includes excellent outreach and training of graduate and undergraduate students, as well as the involvement of high school students, in research. The research results can potentially guide regulatory agencies.
The model used will be the environmentally relevant and commercially significant rainbow trout, Oncorhynchus mykiss. The investigators will use high throughput sequencing to understand the changes in the microbiome, specifically, the effects of dietary exposure to NPs will be determined by global genomic sequencing of the microbial communities and quantitative PCR to target specific microbial species. Changes in abundance of the specific microbes will be evaluated among treatments and over time. In the same fish, gene expression profiling will be conducted to identify biomarker genes that respond to alterations in the microbial community composition. A subset of NP treatments will be selected to conduct longer-term exposure in fish that will subsequently be exposed to Y. ruckeri and the outcome of this bacterial challenge will be evaluated.
Agency: NSF | Branch: Standard Grant | Program: | Phase: ENERGY FOR SUSTAINABILITY | Award Amount: 8.00K | Year: 2016
The co-production of valuable chemicals and materials can improve the economic viability of bio-refinery processes that convert renewable biomass resources into biofuels. To serve as a forum for emerging bio-refinery concepts, the fourth scientific conference in the Frontiers in Biorefining series, titled Chemicals and Materials from Renewable Carbon, will be held during November 2016, at St. Simons Island, Georgia. This conference will assemble scientists and engineers from around the world to share recent progress, explore information needs, and present ideas that advance integrated bio-refinery concepts. A total of 90 participants from academia, government, and industry are expected. This award will support the travel of five graduate student researchers to present their original research at the conference, and to network with influential scientific and industrial researchers in the field of biorefining.
As research programs continue to build the body of fundamental science that create new bio-refinery concepts, a scientific conference to facilitate networking, exchange ideas, and further collaboration between scientists and research institutions is timely. The opening plenary session will highlight key developments in emerging bio-refinery concepts by invited scientists. The subsequent technical program emphasizes pathways for conversion of biomass to useful and valuable chemicals and materials in six parallel sessions and a student poster reception. Specific sessions are: Engineered feedstocks for the bio-refinery; Cell wall deconstruction and biomass fractionation; Catalytic conversion of lignin; Catalytic conversion of carbohydrates; Biochemical conversion of carbohydrates and lignin; Catalytic thermochemical conversion of whole biomass; The interface of biomass and petrochemicals. An open-access, peer-reviewed paper will summarize the activities at the conference in an effort to guide future research, funding opportunities, and policymaking in the fields of biorefining and bioenergy.
Agency: NSF | Branch: Standard Grant | Program: | Phase: ENVIRONMENTAL SUSTAINABILITY | Award Amount: 20.00K | Year: 2016
Food production is closely linked to energy consumption, water/soil resources, and ecosystem conditions. This workshop aims to develop an integrative research, education, and industry agenda for securing food production, producing clean energy, protecting water resources, and improving soil productivity while developing economy and social wellbeing. Conference sessions and panel discussions will address important issues from an international perspective.
Specific workshop topics include: (1) Food Security and Safety - The workshop will overview the existing problems and potential risks associated with food production in terms of the demands of food quantity and quality. New methods of characterizing the cycling processes of matter and energy in agroecosystems will be discussed; (2) Energy Efficiency and Impact - Workshop participants will discuss specific technologies and policies that offer the greatest possibility of high efficient utilization of fossil fuels and renewable energy resources including biomass and water. The workshop is expected to create international joint research teams to further investigate these issues from life cycle and multi-dimensional perspectives; (3) Water Efficiency and Recycling - Workshop participants will exchange technologies and perspectives on water-saving agriculture and wastewater utilization. In particular, urban storm water management will be addressed; (4) Soil Productivity and Remediation - The workshop will address the latest approaches to promoting soil fertility and productivity and safe use of contaminated arable lands for food or non-food purposes. A joint team is expected to be establish for developing modeling tools that could predict threshold values of contaminants (especially heavy metals) for ensuring food quality and ecosystem health.