Page Banner

United States Department of Agriculture

Agricultural Research Service

Research Project: INTEGRATED MANAGEMENT OF INSECT PESTS IN STORED GRAIN AND IN PROCESSED GRAIN PRODUCTS
2006 Annual Report


1.What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)? How serious is the problem? Why does it matter?
Stored-product insect pests reduce the quality of stored grain and grain-related products in the U.S. and in the world. Over 12 billion bushels of corn and wheat are grown in the U.S. each year, with a value of over 25 billion dollars. In addition, over a billion bushels of barley, oats, rice, rye, and sorghum are grown in the U.S. each year, with a value of over 3 billion dollars. It is estimated that postharvest losses to these grains due to insects are 5 to 10%, or about 1.4 to 2.8 billion dollars. Losses to processed commodities, which are difficult to quantify, may greatly exceed dollar losses to raw commodities because of their greater economic value. There is a need to improve integrated pest management (IPM) of stored product insects by identifying new control agents, that are safer and more environmentally friendly, and the factors that affect susceptibility to these agents; developing effective control strategies using combinations of these agents; testing the application and integration of these control strategies in actual industrial environments; and determining the vulnerabilities of economically important insect pests to various control agents. Insect pathogens are potential additions to integrated pest management programs for stored products, but they may not give effective control by themselves. However, control could be enhanced by using them in combinations or along with disruption of insect immune systems.

The loss of methyl bromide used as a fumigant to treat the entire plant, presents us with a unique opportunity to develop smaller-scale insect control strategies that specifically target locations within a food production or storage facility that are vulnerable to insect pest infestation. Our goal is to improve IPM through selective application of safer control agents and non-chemical control methods and to identify the vulnerabilities in insect immune systems that can be exploited to make these control agents more effective. This will benefit food manufacturers and handlers by decreasing the levels of chemicals currently needed to protect our food supply from insect pests and it will lead to a wholesome, more dependable food supply for consumers.

This research has three major objectives:.
1)Identify and refine safe, environmentally friendly control methods and physical controls to manage stored-product insect pests;.
2)Evaluate selective targeted controls and application strategies to manage insect pests in actual industrial environments; and.
3)Identify vulnerabilities in insect physiological and biochemical stress responses that could be exploited to improve the effectiveness of these control methods.

The research supports National Program 304, Crop Protection and Quarantine, and addresses elements of Research Component A, Insects and Mites, and focuses primarily on the subcomponents Postharvest, Pest Exclusion, and Quarantine Treatment; Pest Control Technologies; Biology of Pests and Natural Enemies (including microbes); and Integrated Pest Management Systems and Areawide Suppression Programs. The results are also relevant to National Program 308 Methyl Bromide Alternatives, particularly the subcomponent Post-harvest Commodity Treatment (Including Structural). Attaining these objectives will result in new products and methods for managing insect pests in diverse storage systems, including milling and processing facilities, food warehouses, urban storage, and stored raw grain. Knowledge of specific physiological responses can be used to enhance and improve control when using newer reduced-risk low-toxicity insecticides, pathogens, and physical methods.


2.List by year the currently approved milestones (indicators of research progress)
2006

Continue evaluations for new applications or uses of the Insect Growth Regulators (IGR) hydroprene and methoprene on different surface substrates. Evaluate new techniques for using the pathogens Beauveria and Mattesia for control of insects in stored grain. Conduct bioassays of physical controls combined with pathogens for control of insects in stored grain. Develop assays for stress biomarkers for insects in stored grain. Continue with studies for heat treatment of rice kernels for control of insects. Initiate project for summer aeration of stored wheat for control of insects. Complete data analysis for aeration projects for control of insects in stored grain. Evaluate surface treatments to floors and walls of milling facilities for control of insects. Initiate second year of targeted studies for insect control in grain bins. Initiate second year of study with surface compared to whole-bin treatments of insecticides for control of insects in stored wheat. Collect insect population and Mattesia prevalence data in stored grain. Initiate study with Mattesia and parasitic wasps for control of insects in stored wheat. Initiate studies to determine interaction between DE dusts and lipids in different species of insects. Prepare micro-arrays for genetic tests with insect immune responses to stress. Develop experimental protocols for initial experiments with gene systems in pathogens to study insect immune response.

2007

Continue evaluations for new applications or uses of the IGRs hydroprene and methoprene on different surface substrates. Analyze data from completed studies on new applications or uses of the IGRs hydroprene and methoprene on difference surface substrates. Correlate stress response in insects with susceptibility to pathogens. Evaluate combinations of IGRs and DEs as surface treatments for control of insects in stored grain. Continue with heat treatment studies of rice kernels for control of insects (test different species of insects). Conduct second year of study on summer aeration of stored wheat for control of insects. Analyze data for lab and field studies with targeted treatments for control of insects in grain bins. Analyze data and write manuscript from study with surface compared to whole-bin treatments of insecticides for control of insects in stored wheat. Continue study to collect insect population and Mattesia prevalence data in stored grain. Continue study with Mattesia and parasitic wasps for control of insects in stored wheat. Complete studies to determine interaction between DE dusts and lipids in different species of insects, and analyze data from initial studies. Continue micro-array studies for genetic tests with insect immune responses to stress. Quantify genetic responses of insects to pathogens, heat treatments, and other physical controls.

2008

Continue evaluations for new applications or uses of IGRs on different surface substrates. Write manuscripts on completed studies on new applications or uses of the IGRs hydroprene and methoprene on difference surface substrates. Analyze data and write manuscripts on combination studies of IGRs and DEs as surface treatments for control of insects in stored grain. Analyze data for heat treatment studies of rice kernels for control of insects (test different species of insects). Conduct third year of study on summer aeration of stored wheat for control of insects. Complete analyses and write manuscripts for lab and field studies with targeted treatments for control of insects in grain bins. Model effectiveness of Mattesia to suppress specific stored-product insect species. Complete data analysis and write manuscripts on studies to determine interaction between DE dusts and lipids in different species of insects, and analyze data from initial studies. Develop experimental protocols to measure insect immune responses. Document susceptibility of insects with silenced immune response genes to pathogens. Continue to quantify genetic responses of insects to pathogens, heat treatments, and other physical controls.

2009

Continue evaluations for new applications or uses of IGRs on different surface substrates. Complete analysis of data and write manuscripts for heat treatment studies of rice kernels for control of insects. Analyze data for study on summer aeration of stored wheat for control of insects. Write manuscripts on studies with Mattesia and parasitic wasps for control of insects in stored wheat. Complete data analysis and write manuscripts on studies to determine interaction between DE dusts and lipids in different species of insects, and analyze data from initial studies. Determine gene regulation by insects in response to stress induced by control agents. Begin analysis of results on susceptibility of insects with silenced immune response genes to pathogens. Confirm gene systems involved and regulation of production of heat shock proteins by insects in response to physical controls and begin analysis of results.


4a.List the single most significant research accomplishment during FY 2006.
Food material negatively affects control from aerosol insecticides. Aerosol insecticides are used to control insects in food processing facilities, but we need more information to optimize the effectiveness of these aerosols. Scientists at the Grain Marketing and Production Research Center in Manhattan, KS, conducted a field test whereby adult confused flour beetles were exposed with 0 to 2,000 mg of flour to a pyrethrin-cabon dioxide aerosol inside an open warehouse. Survival of beetles increased with the presence of flour, indicating that the food material compromised effectiveness of the aerosol. There were also problems with uneven distribution of the aerosol inside the test warehouse. Although aerosols show potential for replacing whole-plant fumigations, if proper sanitation is not practiced the aerosol will be less effective for insect control, particularly with adult beetles. Also, the aerosol systems must deliver the product throughout the entire facility that is being treated. This research addresses National Program 304, Crop Protection and Quarantine, Research Component A, Insects and Mites, subcomponents Postharvest, Pest Exclusion, and Quarantine Treatment and Pest Control Technologies.


4b.List other significant research accomplishment(s), if any.
Diatomaceous earth is not equally effective on all grains. Diatomaceous earth (DE) is used for insect control in stored grain, but more information is needed to optimize efficacy. Scientists at the Grain Marketing and Production Research Center in Manhattan, KS, treated rough rice with the labeled application rates of two commercial DE products and exposed adult lesser grain borers, a major pest of stored grains, for different time periods and temperatures. Adult mortality increased with increasing time of exposure up to a maximum of 60 to 70% for both commercial formulations, and there was extensive progeny production in the treated rice. Results show that although these two commercial DE formulations had previously given good control of the lesser grain borer on stored wheat, they were not as effective on rough rice. Therefore, different application rates of DE may be necessary to give complete control of the lesser grain borer on different grain types. This research addresses National Program 304, Crop Protection and Quarantine, Research Component A, Insects and Mites, subcomponents Postharvest, Pest Exclusion, and Quarantine Treatment and Pest Control Technologies.

The insect growth regulator methoprene eliminates progeny production of the lesser grain borer. Scientists at the Grain Marketing and Production Research Center in Manhattan, KS, combined the natural inert dust diatomaceous earth (DE) with the insect growth regulator (IGR) methoprene and applied the combination at different rates to long-grain, medium-grain, and short-grain rough rice. Mortality of adults was only 60% at the label rate of DE, and there were differences among the rice types. However, when methoprene was included in the insecticide treatment, no offspring were produced. Results show that methoprene by itself will eliminate progeny production of the lesser grain borer, but the addition of DE will give some control of adults and could limit damage from adult feeding. This research addresses National Program 304, Crop Protection and Quarantine, Research Component A, Insects and Mites, subcomponents Postharvest, Pest Exclusion, and Quarantine Treatment and Pest Control Technologies.

Biological pesticide spinosad controls the lesser grain borer in stored wheat. New insecticides are needed to control insects in stored grain. Scientists at the Grain Marketing and Production Research Center in Manhattan, KS, tested the newly-approved and environmentally safe insecticide spinosad on Kansas farms and in laboratory studies to examine efficacy and persistence under typical field conditions. In the field tests, no live lesser grain borers were found in any grain treated with spinosad, the residues killed adults during a 6-9 month storage period, there were few progeny, and residues did not degrade over time. Data were used to support registration, which was granted by the US-EPA. This reduced-risk insecticide is scheduled to be marketed in the 2007 season. This research addresses National Program 304, Crop Protection and Quarantine, Research Component A, Insects and Mites, subcomponents Postharvest, Pest Exclusion, and Quarantine Treatment and Pest Control Technologies.

Test assay developed to detect insect pathogens in stored-product insect pests. Naturally occurring pathogens of insects can potentially be exploited for insect control, but a simpler way to determine their presence in insects is required. Scientists at the Grain Marketing and Production Research Center in Manhattan, KS, developed a test assay to detect Mattesia oryzaephili, a pathogen of grain beetles through tests with laboratory colonies from different field sources. This assay will enable researchers to assess the impact of M. oryzaephili on pest populations and to determine the potential to exploit the pathogen by conservation or introduction where it does not occur, and will also allow scientists to maintain health and vigor of laboratory colonies by monitoring these cultures for insect pathogens. This research addresses National Program 304, Crop Protection and Quarantine, Research Component A, Insects and Mites, subcomponents Postharvest, Pest Exclusion, and Quarantine Treatment and Pest Control Technologies.


4c.List significant activities that support special target populations.
None.


4d.Progress report.
None.


5.Describe the major accomplishments to date and their predicted or actual impact.
Combination treatments of reduced-risk insecticides can be more effective than either product used alone. Although some newer insecticides may appear to be less effective than older conventional insecticides, using the combination may offer more complete control. An example is pairing the insect growth regulator methoprene, which does not kill adult insects, with diatomaceous earth, a natural dust that often will not completely control the lesser grain borer in stored grains. The methoprene eliminates progeny production, while the DE kills many but not all of the exposed adults. This new scientific knowledge describes a potential impact in that the adoption of these reduced-risk insecticides may decrease reliance on the use of phosphine, a potentially lethal fumigant that is heavily used by the grain industry for insect control. Customers of this research include anyone involved in pest management in stored bulk grains. This research addresses National Program 304, Crop Protection and Quarantine, Research Component A, Insects and Mites, subcomponents Postharvest, Pest Exclusion, and Quarantine Treatment and Pest Control Technologies.

Targeted treatments with contact insecticides and with aerosols can effectively control insects in mills, processing facilities, and food warehouses. Our research has shown that selective use of targeted surface treatments and aerosols can potentially replace whole-plant fumigations with methyl bromide, which is scheduled for phase-out and is being used now under a critical use exemption (CUE) process. This new knowledge has a potentially huge impact in that reliance on methyl bromide fumigation can be eliminated through new management and control technologies. Some of our customers have already eliminated methyl bromide fumigations through the use of targeted aerosol treatments. Customers of this research include persons involved in quality maintenance and insect control in processed grain products. This research addresses National Program 304, Crop Protection and Quarantine, Research Component A, Insects and Mites, subcomponents Postharvest, Pest Exclusion, and Quarantine Treatment and Pest Control Technologies.

Interaction of microbial pathogens and insect immune responses. Knowledge developed regarding the response of insects and the detection of pathogens in pest populations offers new potential for using naturally-occurring insect pathogens as part of control programs. This alternative provides a means of using insect control in those areas where insecticides are limited, such as organic food production, a rapidly-growing economic segment of the food industry. The potential impact of a natural means of insect control in organic production would be a significant benefit for this specialized industry. Customers of this research include persons involved in insect control in bulk grains, and with responses of insect populations to microbial pathogens. This research addresses National Program 304, Crop Protection and Quarantine, Research Component A, Insects and Mites, Biology of Pests and Natural Enemies (including microbes).


6.What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end-user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products?
We provided scientific information, data, interpretation, and technical support for several segments of the stored-product market, including grain storage, milling and processing, and warehousing. New reduced risk low toxicity insecticides were identified as potential registrations for the postharvest market.


7.List your most important publications in the popular press and presentations to organizations and articles written about your work. (NOTE: List your peer reviewed publications below).
Arthur, F. H. Controlling Stored Product Pests with Insecticides: A New Look. Pest Control Technology Stored Product Pest Seminar, November, 16-18, 2005, Minneapolis, MN.

Arthur, F. H. Control of Indianmeal Moth Using Insect Growth Regulators and Surface Treatment for Controlling insects in Stored Grain: Laboratory and Field Studies. 2006 Nebraska Urban Pest Management Conference, January 26-27, 2006, Lincoln. NE.

Arthur, F. H. Diatomaceous Earth Plus Methoprene for Control of Lesser Grain Borer, Rhyzopertha dominica, in Rough Rice and Susceptibility of Long, Short, and Medium-Grain Rice to Rhyzopertha dominica F., the Lesser Grain Borer. 31st Rice Technical Group Meeting, February 26 –March 1, 2006, Woodlands, TX.

Arthur, F. H. Insect Pest Complex and Control in Stored Farmers Stock Peanuts and Storage and Management of Peanuts. Training session organized by Birdsong Peanut Company and Wellmark International. April 18 in Blakely GA, April 20, 2006, Suffolk, VA.


Review Publications
Arthur, F.H., Siebenmorgen, T.J. 2005. Historical weather data and predicted aeration cooling periods for stored rice in Arkansas. Applied Engineering in Agriculture 21: 1017-1020.

Arthur, F.H., Casada, M. 2005. Feasibility of summer aeration to control insects in stored wheat. Applied Engineering in Agriculture 21: 1027-1038.

Arthur, F.H. 2005. Initial and delayed mortality of late-instar larvae, pupae, and adults of Tribolium castaneum and Tribolium confusum (Coleoptera: Tenebrionidae) exposed at variable temperatures and time intervals. Journal of Stored Products Research 42: 1-7.

Arthur, F.H., Hagstrum, D.W., Flinn, P.W., Reed, C.R., Phillips, T.W. 2005. Insect populations in grain residues associated with commercial Kansas grain elevators. Journal of Stored Products Research 42: 226-239.

Mohandass, S.M., Arthur, F.H., Zhu, K.Y., Throne, J.E. 2006. Hydroprene: mode of action, current status in stored-product pest management, insect resistance, and future prospects. Crop Protection 25: 902-909.

Mohandass, S., Arthur, F.H., Zhu, K., Throne, J.E. 2006. Hydroprene prolongs development time and increases mortality of eggs of Indianmeal moth (Lepidoptera: Pyralidae). Journal of Economic Entomology 99: 1007-1016.

Vardeman, E.A., Arthur, F.H., Nechols, J.R., Campbell, J.F. 2006. Effect of temperature, exposure internal and depth of diatomaceous earth on distribution, mortality, and reproduction of the lesser grain borer, Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae) in stored wheat. Journal of Economic Entomology 99: 1017-1024.

Arthur, F.H. 2005. Impact of aeration on insect pest management in stored rice [abstract]. National Entomological Society of America Annual Meeting, Ft. Lauderdale, FL, November 6-9, 2005.

Arthur, F.H. 2006. Insect growth regulators (IGRs) in pest management programs [abstract]. 5th National IPM Conference, St. Louis, MO, April 3-6, 2006.

Lord, J.C. 2005. Perspectives for biological control of stored-product pests using entomopathogens, alone and in combination with beneficial insects [abstract]. National Entomological Society of America Annual Meeting, Ft. Lauderdale, FL, November 6-9, 2005.

Lord, J.C. 2006. Interaction of Mattesia oryzaephili with Cephalonomia spp. (Hymenoptera: Bethylidae) and their hosts Cryptolestes ferrugineus (Coleoptera: Laemophloeidae) and Oryzaephilus surinamensis (Coleoptera: Silvanidae). Biological Control 37: 167-172.

Toews, M.D., Pearson, T.C., Campbell, J.F. 2006. Imaging and automated detection of Sitophilus oryzae L. (Coleoptera: Curculionidae) pupae in hard red winter wheat. Journal of Economic Entomology 99: 583-592.

Campbell, J.F., Toews, M.D. 2005. Monitoring Indianmeal moth inside and outside. AIB Quarterly, Quality Assurance and Food Safety, Fall, 2005.

Last Modified: 12/20/2014
Footer Content Back to Top of Page