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We will conduct field and laboratory studies on fumigant alternatives for controlling arthropod pests of dried meats and other durable food products. Methyl bromide alternatives will be given to producers of southern dry cured hams for pest disinfestations. We expect to provide one or more effective alternative controls that will allow them to store and market a pest-free, high-quality product. This project will develop detection methods and will survey the incidence of phosphine resistance in populations of stored grain insect pests. The grain storage industry will then have knowledge about the actual or potential effectiveness of phosphine against their insect pests based on resistance, and will have a list of options from our work to help in alternative control procedures. We will investigate the efficacy and utility of the gas chlorine dioxide as a methyl bromide alternative for fumigation of flour mills and other value-added food structures. We expect chlorine dioxide may become a new alternative to methyl bromide for fumigation of flour mills, one that was not available before. <P>The project will study the pharmacokinetics and binding affinity of the bacterial insecticide Spinosad in Rhyzopertha dominica, the lesser grain borer, a serious insect pest of stored cereal grains. By understanding the mode of action of Spinosad in the lesser grain borer we should be able to deliver techniques that enhance the toxicity of Spinosad for an insect pest species that currently is more tolerant to this natural product insecticide. We will evaluate various residual insecticides for control of major insect pests of stored corn in Kansas. This will provide the corn industry with useful tools to control pests that they have lacked up until now. Each of the five projects is described independently and with enough detail that each can be reviewed separately. Adequate detail is provided for the scientifically literate reader to understand the problem, evaluate the scientific approaches, and appreciate the potential products and impacts of the work. The audience for this projects includes, but is not limited to, other scientists, agricultural producers, participants in the dried meat and cheese industries, the grain storage industry, flour millers and other food processors, pesticide companies and government regulatory agencies
Non-Technical Summary:<br/>
This is a multiple principal investigator (PI) project that involves three professors from the departments of Entomology and Grain Science and Industry. There are a total of five main projects to be conducted and all under the general topic area of protecting durable stored food products, those not requiring refrigeration, from insects, molds and other depredations that result in damage and value loss. The five studies vary from being basic science and preliminary in nature to being field trials to confirm work done in the laboratory. Funding from outside KSU is already available for most of the projects, while results from some objectives proposed here will serve as justification and preliminary data for writing new grant proposals during the time period of this project. The five projects are as follows. Conduct field and laboratory studies on alternatives to fumigant toxic gases for controlling pests of dried meats and other foods. Develop detection methods and survey the incidence of fumigant resistance in stored grain insect pests and investigate resistance management strategies. Investigate the efficacy and utility of a new gas, chlorine dioxide, as an alternative to fumigation with methyl bromide, which is scheduled to be banned. Do basic research on the way the insecticide Spinosad, which comes from a bacterium, can kill the grain beetle called the lesser grain borer, a serious insect pest of stored grains. Evaluate legal insecticides for controlling major insect pests of stored corn in Kansas.
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Approach:<br/>
Dry cured hams will be fumigated in shipping containers at concentrations between up to 3000 ppm phosphine for 48 and 72 hrs to evaluate their effectiveness at controlling ham mites and ham beetles since these concentrations have shown promise in laboratory and testing in shipping containers. Bioassays will confirm that the concentration used under controlled conditions will work under commercial conditions. Sensory testing and chemical analysis will be conducted with treated hams to verify that the ham and cheese products have acceptable sensory quality and have residual concentrations of phosphine that are below the legal limit of 0.01 ppm. A mite trap will be developed with a food bait placed in the middle of a circular shelter covered with a durable round cover. The cover has a clearance of about 2 mm. above the ground when the trap is deployed. Mites in the vicinity of the trap orient to it, enter the shelter under the cover and associate with the food bait where they become arrested with feeding, mating and oviposition. With respect to Integrated Pest Management, a general HACCP-based IPM plan will be developed for dry cured ham, and individual IPM-based HACCP plans will be developed for individual products in the four plants. The presence of phosphine resistance in all populations of key grain beetle species will be determined using established methods. Groups of beetles will be exposed to discriminating doses of of phosphine. Any insect surviving will be considered as resistant. Methods for studying the response of insect and mite species to sulfuryl fluoride (SF) are well established. PH3-resistant insects from each species will be subjected to a high and low dose exposures to SF within the published label ranges for this compound. Such information will be used toward a field trial of SF as an alternative to phosphine to curb resistance. Chlorine dioxide gas, ClO2, is generated in water by tablets provided by the company. The gas release container is connected to the exposure chamber. The same set up will be used for exposing various life stages of the red flour beetle. Beetles will be reared on a diet of wheat flour with 5 percent (by wt) brewer's yeast. Each 0.94-L glass Mason jar with 200 g of the insect diet will be seeded with 100 beetle adults. The Hal Ross flour mill, affiliated with the Department of Grain Science and Industry, Kansas State University, is a pilot scale mill that will be used for ClO2 field treatments. Bioassay boxes will be placed in the mill and then brought to the laboratory and incubated at 28 degrees C and 65percent RH. The number of live and dead adults will be determined 24 h after collecting all bioassay boxes. Dose-response tests with R. dominica adults will be generated with unlabeled spinosad to determine the range of concentrations required for radiolabeled spinosad experiments. We will then use radio-labeled spinosad to determine rates of cuticular penetration, detoxification and excretion. Laboratory bioassays will be conducted to determine relative efficacy of various insecticides labeled for empty bin residual sprays against important insect pests of corn when exposed to treated surfaces.