Location: Agroecosystem Management Research
2016 Annual Report
Objectives
Objective 1: Develop sustainable methods for the management of stable flies and other flies impacting livestock production.
Sub-objective 1.1 Identify and test larvicides for stable flies and other flies developing in livestock wastes.
Sub-objective 1.2 Develop attractants for use on traps.
Sub-objective 1.3 Develop adult fly repellents with extended residual activity.
Sub-objective 1.4 Evaluate effects of stable flies on behavior and productivity of cattle.
Sub-objective 1.5 Evaluate the effectiveness of a Push-Pull stable fly management strategy.
Objective 2: Characterize effects of biological, chemical, and physical substrate properties on stable fly larval development.
Sub-objective 2.1 Characterize functional groups of microorganisms in substrates associated with stable fly and house fly larval development.
Sub-objective 2.2 Identify endosymbionts and parasitoids associated with stable flies.
Sub-objective 2.3 Characterize nutritional factors required for stable fly larval development.
Objective 3: Develop a physiologically based demographic model (PBDM) to predict temporal and spatial patterns of stable fly population dynamics under current and potential climatic conditions.
Sub-objective 3.1 Determine physiological responses of stable fly developmental stages to environmental variables.
Sub-objective 3.2 Incorporate parameters from 3.1 into PBDM.
Sub-objective 3.3 Validate PBDM.
Approach
Stable flies are among the most serious arthropod pests of livestock in the United States, costing producers in excess of $2 billion per year in lost production. They exhibit an extraordinary ability to adapt to, and exploit, regional agricultural and animal husbandry practices. Stable fly management has proven to be a daunting task largely due to their adaptability, mobility, and gaps in our knowledge of their behavior and biology. This project will address all of these issues. Primarily, the project will develop new methods for the management of stable flies by exploiting the most vulnerable stages in their life cycles. Secondarily, we will develop a better understanding of stable fly biology and how they interact with their environment and hosts. Finally, new and existing information on stable fly biology will be incorporated into a dynamic, physiologically-based demographic model. This model will permit us to predict the dynamics of stable fly populations under real and potential environmental conditions, as well as provide insight into the validity of our understanding of their interactions with biotic and abiotic factors in the environment for development and reproduction. Successful completion of this project will result in new technologies for the management of stable fly populations, reduced impact of stable flies on livestock production systems, and a greater understanding of their biology for the continued development and evolution of stable fly management technologies.
Progress Report
Larvicides. In collaboration with Costa Rican colleagues, several chemical control agents for larval stable flies were evaluated on pineapple residues, benzylureas (Triflumuron, Diflubenzuron and Novaluron), Cyromazine and Buprofezin. All except Buprofezin provided good control (Subobjective 1.1).
Chemical ecology. New short chain fatty acids (C3, C5, C6), as well as other nitrogen- and sulfa compounds identified from sugar cane vinasse, a byproduct of sugar fermentation, were found to have strong electroantennagraphic responses from adult stable flies. Traps baited with these compounds are being tested in Brazil and Nebraska. Evaluation of several of these compounds for use as oviposition attractants is under way. Materials for an auto-trapping system for stable fly mass trapping were evaluated as part of a CRADA. (Subobjective 1.2).
New compounds from coconut oil were isolated and identified (invention disclosure submitted). Their repellency against biting flies (stable fly and horn fly), ticks, bed bugs and mosquitoes were evaluated, with strong repellency observed. Laboratory longevity tests showed effectiveness up to 2-weeks for biting flies and 1 week for bed bugs and ticks. Longevity and effectiveness are better than those of DEET. (Subobjective 1.3).
Larval substrates and microbial ecology. Microbial communities in several different substrates supporting stable fly larval development were characterized with metagenomics. Microbial communities associated with larval guts were compared with those of the substrate to determine how stable fly larvae were utilizing and processing microbes in their environments. (Subobjective 2.3).
Life history. The effects of supplementing larval developmental substrates with ammoniacal salts were evaluated. The addition of ammonium bicarbonate to a standard laboratory diet more than doubled egg to pupa survival with no effect on pupal weight. Other ammoniacal salts including ammonium chloride, ammonium hydroxide, ammonium phosphate and ammonium sulfate had either no effect or a negative effect on survival.
The effects of temperature and protein and carbohydrate concentrations in larval developmental substrates upon development and survival were evaluated. Temperature had the greatest effect upon size and developmental time. Diet had the greatest effect upon adult size. Effects of all parameters on microbial communities are being evaluated with metagenomic techniques.
The collaborative investigation to evaluate the mechanisms used by stable flies to colonize environments in the spring in diverse geographical regions of the United States and Canada is continuing for a second year.
Analysis of weather parameters on stable fly trap collections in a thirteen year dataset from eastern Nebraska has been completed. Temperature 0 to 3 weeks before collection date had the greatest effect upon trap catches followed by precipitation 2 to 7 weeks prior to collection. Optimal conditions for stable flies were a mean temperature of 21°C and a mean of 10 mm of precipitation per day. (Subobjective 3.1).
Control. Evaluations of an insecticide impregnated screen continued. Approximately 900 meters of screen were installed along the sides of a 1500 cow dairy with two open stall barns. Mortality evaluated directly under the screen was approximately 50 stable flies per meter per day. These mortality figures are underestimates of actual mortality because most of the flies contacting the screen were able to fly a short distance before dying and were not collected in the trays below the screen. Counts of stable flies on cows in the treated barns were negligible whereas those on cows in an untreated barn were 20-30 flies per animal. An ultralow volume formulation of Deltamethrin (DeltaGuard) was evaluated. Treatment reduced the number of biting stable flies per animal from 20-30 to 5-8. Field trials of Push-Pull strategy for stable fly control are continuing with pastured cattle this summer (Subobjective 1.5).
Accomplishments
1. Novel botanically-based insect repellant. Flies and other biting insects are annoying and potentially dangerous as a result of their abilities to transmit diseases to humans and livestock. Scientists from Lincoln, Nebraska discovered a novel anti-feeding and repellent compound(s) from a natural product, coconut oil. These compounds provide up to 2-weeks of repellency against biting flies, one-week against bed bugs and ticks. The compound(s) are also effective for preventing mosquitoes from biting. Efficacy of this compound is comparable, and in some cases better, than that of DEET, the best biting insect repellent commercially available.
None
Review Publications
Genzhong, C., Zhu, J.J. 2016. Pheromone-based pest management in china: past, present and future prospects. Journal of Chemical Ecology. Available: https://link.springer.com/article/10.1007/s10886-016-0731-x.
Zhu, J.J., Zhang, Q., Taylor, D.B., Friesen, K.M. 2016. Visual and olfactory enhancement of stable fly trapping. Pest Management Science. 72:1765-1771.
Chaudhury, M.F., Zhu, J.J., Skoda, S.R. 2016. Bacterial volatiles attract gravid secondary screwworms (Diptera: Calliphoridae). Journal of Economic Entomology. 109(2):947-951.
Zhu, J.J., Baker, T., Millar, J.G., Romeo, J. 2016. Semiochemicals in pest management: development, regulation and applications. Subtitle: Delivering on the promise of pheromones. Journal of Chemical Ecology. Available: http://link.springer.com/article/10.1007/s10886-016-0744-5.
Friesen, K.M., Berkebile, D.R., Wienhold, B.J., Durso, L.M., Zhu, J.J., Taylor, D.B. 2016. Environmental parameters associated with stable fly (Diptera: Muscidae) development at hay feeding sites. Environmental Entomology. 45(3):570-576.
Solorzano, J., Guilles, J., Bravo, O., Vargas, C., Gomez-Bonilla, Y., Bingham, G., Taylor, D.B. 2015. Biology and trapping of stable flies (Diptera: Muscidae) developing in pineapple residues (Ananas comosus) in Costa Rica . Journal of Insect Science. 15(1):145.
