Page Banner

United States Department of Agriculture

Agricultural Research Service

JAMES F. CAMPBELL (JIM)

Research Entomologist

Photo of Dr. James Campbell

Dr. James Campbell
Research Entomologist

Stored Product Insect Research Unit
Center for Grain &
Animal Health Research

1515 College Ave.
Manhattan, KS 66502


Voice: (785) 776-2717
Fax: (785) 537-5584


james.campbell@ars.usda.gov
www.ars.usda.gov/npa/cgahr/spiru/campbell

Research Interests

Jim Campbell is a Research Entomologist with the USDA ARS Center for Grain and Animal Health Research in Manhattan, KS. He received B.S. and M.S. degrees from Rutgers University and a Ph.D. in Entomology from the University of California-Davis. His research interests include the behavior of stored product insects and their natural enemies and how the use of behavioral information can improve the management of insect pests.


Current Research Projects

Evaluation of Structural Fumigation Efficacy for Management of the Red Flour Beetle
Fumigation of food processing and storage structures with methyl bromide for the control of stored-product insect pests has been a commonly used tool for many years. However, methyl bromide has been identified as an ozone depleting substance, and most of its applications are being phased out worldwide under an international treaty called the Montreal Protocol on Substances that Deplete the Ozone Layer. This process has triggered a need to evaluate the impact of methyl bromide fumigations on pest populations as a baseline, and then to assess the impact of other treatments to determine if they are viable alternatives. The red flour beetle (Tribolium castaneum) is a major pest of wheat and rice mills, and its management has relied heavily on fumigation with methyl bromide. However, there was little information on pest population dynamics and impact of fumigations within food processing facilities. Recent research has focused on the evaluation of fumigation efficacy in commercial mills – of both methyl bromide and an alternative fumigant sulfuryl fluoride – and how the need to fumigate could be reduced through other integrated pest management strategies. Red flour beetle was monitored using pheromone and food-baited traps placed both inside and outside the mills over multiple years at multiple mill locations to obtain the data needed for this type of analysis.

Although superficially wheat and rice mills have much in common and share the same primary pest, the population dynamics of red flour beetle were very different between the two mill types. Analysis of seasonal patterns in pest activity in wheat mills indicated that populations persisted and continued to increase all year round, although the rate of increase was less in the winter. This was because high enough temperatures were maintained inside all year round to support pest development. Immigration of beetles into the mill from outside sources also appeared to be relatively low in wheat mills. Analysis of this monitoring data also identified threshold values below which beetle captures in traps did not change significantly between monitoring periods, suggesting that this might be a useful management target to reduce risk. In rice mills, beetle captures inside were more seasonal, with greatly reduced activity in the winter months. Captures of beetles outside was greater and captures inside and outside the mill were positively correlated. Traps placed in areas where rough rice is stored prior to milling often indicated high levels of red flour beetle activity, and this is a potential source of immigrants into the mill. Unlike in the wheat mill data, inside temperatures in the rice mills followed outside temperatures all year round and thus were not favorable for red flour beetle development or movement during much of the winter. These differences in population dynamics and spatial distribution inside and outside the mill could impact fumigation effectiveness.

The immediate impact of a fumigation was assessed by comparing the number of beetles captured in the monitoring period before treatment with those captured in the period immediately after treatment. This change will reflect the decrease due to treatment mortality, but also immigration of new beetles following treatment. In the wheat mill data, the mean number of beetles per trap decreased by 85% following fumigation with methyl bromide, with most fumigation events providing a high level of pest reduction. Beetle captures immediately after fumigation were positively related with those in the period immediately prior to fumigation, which indicates that the higher pest levels are allowed to build prior to treatment the greater the numbers present after treatment will be, and this can lead to more rapid rebound post-treatment. The season that the fumigation was performed did not impact immediate reduction in captures. This suggests that immigration was not a significant contributor to pest activity immediately after treatment. In rice mills using sulfuryl fluoride as an alternative fumigant to methyl bromide, fumigations led to an average 66% reduction in captures of red flour beetle adults, and the percent reduction was highly variable. Unlike in wheat mills, reduction in captures after fumigation was related to outside temperature conditions, which could be due to the tighter association between inside and outside temperatures and/or the influence on beetle movement into the mill. Thus, this difference in immediate reduction in captures between the fumigants is probably due less to differences in fumigant type and more to differences in pest populations between the two mill types.

Rebound in red flour beetle captures after fumigation was also evaluated, and in wheat mills it was found that time of year fumigation was performed and integrated pest management practices performed within the mill after fumigation both significantly impacted rebound time. However, in rice mills beetle captures tended to increase and decrease independently of fumigations, which made rebound patterns difficult to evaluate. Unlike in wheat mills, rebound rate in rice mills was not associated with beetle capture levels prior to fumigation, which suggests that immigration was a significant contributor to post-treatment levels. Overall, captures of beetles in traps rebounded more slowly in rice mills than in wheat mills. Potential differences in rebound due to differences in egg mortality between the two fumigants could not be assessed because of these strong seasonal patterns in immigration and development in rice mills.

These results suggest a fundamental difference in red flour beetle population dynamics and structure between wheat and rice mills, which in turn impacts fumigation effectiveness. They also suggest how treatment efficacy can be evaluated and how monitoring programs might be used to indicate the need to fumigate. Management of rebound rate and keeping pest captures below threshold levels may provide a way to reduce the frequency of fumigations or eliminate fumigations completely. As methyl bromide becomes less available and as fumigation costs increase, use of monitoring information to guide integrated pest management programs is likely to become of increasing importance.

Red Flour Beetle Interactions with Pheromone Traps
Red flour beetle, Tribolium castaneum, is a major pest of flour mills and other food processing facilities. Pheromone traps that capture walking insects are widely used for monitoring this pest inside food processing facilities to aid in making pest management decisions. These traps are typically baited with aggregation pheromone and food-based attractants, but anecdotal reports suggest that response of red flour beetle to these attractants is not very strong. A current research focus has been on evaluating beetle response to these traps with the goals of improving the attractiveness of traps, selection of locations to place traps, and interpretation of monitoring programs.

Although commercial pheromone lures have long been used for monitoring of populations of flour beetles, no one has ever determined either the site of production in the beetle’s body or the natural blend of components (stereoisomers) in the attractant actually produced by the insect, and there is evidence that the commercial blend is not optimized for maximum attractive potency. We showed that the natural pheromone is produced in the abdominal epidermis (outer layer of the “skin”), and is composed of a 4:4:1:1 ratio of four forms of the pheromone (4,8-dimethyldecanal). We also demonstrated that this natural blend is significantly more attractive than the commercial pheromone blend, which is a 1:1:0:0 ratio of the four forms. Using the natural ratio could lead to significant improvements in flour beetle detection in mills and warehouses. Research is now focused on further characterizing the response of beetles to this natural blend.

How well pheromone and food attractants used in traps work under real world conditions has not been previously evaluated. Using a new experimental protocol that simulates how beetles interact with traps in commercial food facilities, we demonstrated that the beetle’s response was strongest to traps baited with pheromone and food attractant, or with pheromone alone, when air flowed from the trap toward the beetle. The beetle’s positive response to traps baited with pheromone and food attractant extended out to a distance of 90 cm (35 inches), the maximum distance tested. However, under still air conditions, beetles did not respond to any of the tested attractants. Within food processing facilities, traps can be placed in sheltered locations with limited air movement or in more exposed areas with high amounts of airflow, with the result that traps may vary in their attractiveness to red flour beetles. Understanding how beetle behavior is influenced by factors such as attractant type and airflow can help guide the selection and placement of traps within a food facility. Research is now focused on evaluation of additional factors that could impact beetle response to traps.

Variation among environmental and physical conditions among locations where traps are placed inside food processing facilities can potentially influence both the distribution of stored-product pests and the effectiveness of traps at capturing them. Data from a long-term red flour beetle monitoring program was used to evaluate spatial variation in captures among trap locations and to determine if differences in environmental and physical conditions at trap locations might be influencing the patterns of trap captures. Evaluating long-term patterns in red flour beetle captures revealed that while over short periods of time beetles were more likely to be found in certain areas of the mill, over longer periods of time areas of greater insect activity moved around the mill resulting in long-term averages that were more uniform among trap locations. Although the characteristics of individual trap locations were found to be highly variable, only warmer temperatures, higher flour dust accumulation, and proximity of milling equipment were associated with traps with high levels of beetle capture. Results indicate that while the environment appeared to have some influence over pattern in beetle captures it was limited, probably because broader patterns of change in distribution within the mill over time, perhaps related to season or increase in total abundance, were more important. Research is now focused on evaluating some of these factors under laboratory conditions and further evaluation of these factors in other food facilities. (Collaborators: Michael Aikins, Kazuaki Akasaka, Dick Beeman, Yujie Lu, Kenji Mori, Yoonseong Park, Tom Phillips, Altair Semeao, Phil Sloderbeck, Shigeyuki Tamogami, and Jeff Whitworth )


Project Information
Evaluation of potential attractants for Liposcelis bostrychophila (Psocoptera: Liposcelididae)
The psocids, also known as booklice, are worldwide insect pests of stored grains that cause significant economic losses by direct feeding and product contamination, and are difficult to control with insecticides. To effectively guide pest management programs it is critical to have a pest-monitoring program, but tools to attract and trap psocids are currently not available. The response of a major stored grain psocid pest species, Liposcelis bostrychophila, to potential attractants (including grains, grain based oils, wheat germ, and brewer’s yeast) was studied, and it was determined that brewer’s yeast, wheat germ and wheat germ oil had the strongest psocid response. These materials appear promising attractants for incorporation into psocid traps and will be further evaluated for monitoring psocids.
     

Spatial pattern in aerosol insecticide deposition inside a flour mill
Aerosol insecticides are applied as small droplets into the air, which then settle onto surfaces to provide control of stored-product insects inside food facilities such as mills and warehouses. Features inside a room such as mill and processing equipment, bins, columns and pallets of food are predicted to impact how these droplets disperse, creating zones within a room with lower droplet deposition and lower insect mortality. We used a high density grid of dishes containing confused flour beetle as a means to determine the amount of insecticide being deposited at a given location and developed a new efficacy index to show that two pyrethrin aerosols did exhibit zones with high and low efficacy within a flour mill. However, rather than the obvious physical barriers it tended to be along walls and in corners where lower efficacy occurred. The temperature when the aerosol was applied also impacted efficacy. A third insecticide, DDVP, that is an organophosphate and readily vaporizes and can cause mortality in the vapor phase was very consistent in causing insect mortality throughout the flour mill. We also used boxes of different heights and open on only one end to evaluate aerosol dispersal under a horizontal surface. Aerosol dispersal under the box decreased with decreasing box height and distance under the box in a way that could be quantified and used to predict where low efficacy is likely to occur within a food facility. These results show the potential for spatial variation in aerosol efficacy within a food facility and identify locations that are likely to receive lower dosages of insecticide and need supplemental treatment to maximize overall efficacy.
     

Movement of Tribolium castaneum within a flour mill
Understanding the movement patterns of stored-product insect pests within food processing or storage facility is important in terms of identifying and targeting pest management at sources of infestation and determining the potential to avoid pest management tactics. In this case study, we demonstrated using a mark-recapture technique that the red flour beetle, Tribolium castaneum, was able to move among floors within a flour mill, but the majority (86%) of beetles were recovered on the same floor they were marked on. For individuals that moved to a different floor, most moved downward (70%) and typically only to an adjacent floor (87%). Use of heat treatments to disinfest structures is an important pest management tool, but insects have the ability to move away from unfavorable temperatures. During a heat treatment of the mill there was an increase in the number of beetles captured, indicating increased movement, but there was not an increase in movement of marked beetles between floors. These results suggest that the rate of heating was sufficient to not allow the beetles time to move to cooler floors and escape the treatment. Results of this study indicate that red flour beetles are mobile enough that sources on other floors need to be considered in making pest management decisions.
     

How Varying Pest and Trap Densities Affect Tribolium castaneum (Coleoptera: Tenebrionidae) Capture in Pheromone Traps
The red flour beetle is an important insect pest of facilities which process and store grain. Integrated pest management frequently includes monitoring populations using traps that capture walking individuals. However, fundamental questions remain about the most effective way to implement monitoring programs and interpret monitoring data to estimate beetle density. Using experiments conducted in room-sized chambers where beetle density and number of traps could be controlled, we found that the number of individuals captured in traps increased as density of beetles increased, but the percentage of individuals captured remained constant. Applying a mathematical equation to estimate beetle density based on captures in traps, we found that a trap density of 4 traps per chamber (1 trap per 80 square feet) yielded the most accurate estimate of beetle density. The more traps placed in the chamber the greater the captures of beetles, but when trap density increased beyond 3 traps per chamber (1 trap per 108 square feet) the increases in beetle captures with each additional trap diminished to the point where there was little justification for the increased costs. This is the first scientific information available to guide the number of traps needed to monitor red flour beetles effectively and to estimate beetle density based on captures in traps.
     

Distribution, Abundance, and Seasonal Patterns of Plodia interpunctella (Hübner) in a Commercial Food Storage Facility
The Indianmeal moth is a major pest of stored food products, but there are few studies where resident populations have been monitored for more than one year in commercial facilities. We monitored Indianmeal moth populations inside a food warehouse for three years using an attractant for male moths. The focal points of infestation shifted during the storage period, but moths were consistently trapped in certain locations. Also, we caught moths in traps that were in places where no food was stored. In general, more moths were caught during the summer months compared to the remainder of the year. Cost estimates for the monitoring program were calculated using values provided by private industry. We used these values to show how reducing the number of traps could provide information on infestation trends while lowering the costs associated with insect monitoring. Results show the importance of monitoring for Indianmeal moths, but also emphasize the dynamic nature of insect infestations inside an active warehouse.
     

Spatio-Temporal Distribution of Stored-Product Pests around Food Processing and Storage Facilities
Stored-product insects can be found outside of facilities where grain is stored and processed, and these populations can potentially serve as a reservoir and source of food product infestation. Identifying the pattern of distribution of pest species and the factors that determine distribution could help in the targeting of monitoring and pest management programs. Pests were monitored using two types of food-baited traps at three food facilities, and the species captured were a mixture of both important grain and processed food pests and fungal feeding species more commonly associated with degraded grain. Although the types of insects captured were similar between inside and outside locations, more were captured per trap inside and fungal feeding species were proportionally more abundant outside. Features of the landscape around each outside trap were characterized to see which might predict locations with more insect activity. Increased captures in outside traps were primarily associated with proximity to buildings, but surprisingly not associated with presence of food spillage. Overall, there was evidence of considerable movement of insects in the landscape surrounding facilities, resulting in limited spatial pattern other than localized hot spots inside or near structures that varied in location overtime. This study presents a methodology for evaluation of external populations at food facilities, highlights the importance of understanding pest populations over larger spatial scales, and provides insight into where monitoring and pest management tactics need to be focused.
     

Tribolium castaneum (Coleoptera: Tenebrionidae) Associated With Rice Mills: Fumigation Efficacy and Population Rebound
The red flour beetle is the most important insect pest infesting rice milling facilities in the U.S. While this pest has traditionally been managed by fumigation with methyl bromide, this fumigant is currently being phased out under the 1987 Montreal Protocol. The purpose of this study was to evaluate the effectiveness of sulfuryl fluoride (SF), an alternative to methyl bromide, in managing red flour beetle infestations in rice mills. Red flour beetle populations in and around seven rice mills were monitored before and after 25 fumigations with SF. Beetle populations were estimated by the number of adults captured in pheromone traps. The SF fumigations led to an average of 66% reduction in captures of red flour beetle adults. Beetle captures at the rice mills were strongly influenced by seasonal changes in temperature, with more beetles being captured during the warmer months and fewer during the cooler months. In addition, red flour beetle captures in traps located inside mills were positively correlated with captures in traps located outside of the mill. Seasonal temperature fluctuations also strongly impacted the length of time required for captures to return to pre-fumigation levels. Similar studies in wheat flour mills did not share the seasonal patterns or correlation between captures inside and outside the mills. These results highlight the importance of treatment timing in maximizing fumigation efficacy in rice mills and suggest there is a fundamental difference in red flour beetle population dynamics and in the impact of fumigation between wheat and rice mills.
     


Agricultural Research Service (ARS) News
News, Miscellaneous
Kansas Scientist Honored for Work Tracking Pantry Pests
Insect Pests Find Pet Stores Irresistible

International Working Conferences on Stored-Product Protection

Dr. Campbell serves as the Secretary/Treasurer of the Permanent Committee for the International Working Conferences on Stored-Product Protection. Tables of Contents for the Proceedings of the IWCSPP can be accessed at spiru.cgahr.ksu.edu/proj/iwcspp/ *.

The next meeting of the International Working Conferences on Stored-Product Protection will be held 24-28 November 2014 in Chiang Mai, Thailand - http://iwcspp2014.com/new/ *.
 
Recent Publications
Article LinkArthur, F. H., J. F. Campbell, and M. D. Toews. 2014. Distribution, abundance, and seasonal patterns of stored product beetles in a commercial food storage facility. J. Stored Prod. Res. 56: 21-32.
Article LinkCampbell, J. F., F. H. Arthur, and K. Y. Zhu. 2014. Spatial pattern in aerosol insecticide deposition inside a flour mill. J. Econ. Entomol. 107: 440-454.
Article LinkDiaz-Montano, J., J. F. Campbell, T.W. Phillips, and J.E. Throne. 2014. Evaluation of potential attractants for Liposcelis bostrychophila (Psocoptera: Liposcelididae). J. Econ. Entomol. 107: 867-874.
Article LinkKharel, K., F. H. Arthur, K. Y. Zhu, J. F. Campbell, and B. Subramanyam. 2014. Evaluation of synergized pyrethrin aerosol for control of Tribolium castaneum and Tribolium confusum (Coleoptera: Tenebrionidae). J. Econ. Entomol. 107: 462-468.
Article LinkKharel, K., F.H. Arthur, K.Y. Zhu, J.F. Campbell, and Bh. Subramanym. 2014. Susceptibility of different life stages of Tribolium confusum to pyrethrin aerosol: effects of a flour food source on insecticidal efficacy. J. Pest Sci. 87: 295-300.
Article LinkPerez-Mendoza, J., J.F. Campbell, and J.E. Throne. 2014. Effect of abiotic factors on initiation of red flour beetle (Coleoptera: Tenebrionidae) flight. J. Econ. Entomol. 107: 469-472.
Article LinkTucker, A.M., J.F. Campbell, F.H. Arthur, and K.Y. Zhu. 2014. Mechanisms for horizontal transfer of methoprene from treated to untreated Tribolium castaneum (Herbst). J. Stored Prod. Res. 57: 36-42.
Article LinkTucker, A.M., J.F. Campbell, F.H. Arthur, and K.Y. Zhu. 2014. Horizontal transfer of methoprene by Tribolium castaneum (Herbst) and Tribolium confusum Jacquelin du Val. J. Stored Prod. Res. 56: 73-79.
pdf icon PDF Arthur, F.H., J.F. Campbell, and M.D. Toews. 2013. Distribution, abundance, and seasonal patterns of Plodia interpunctella (Hübner) in a commercial food storage facility. J. Stored Prod. Res. 53: 7-14.
pdf icon PDF Arthur, F.H., J.F. Campbell, E.A. Fontenot, and M.D. Toews. 2013. Assessing effects of esfenvalerate aerosol applications on resident populations of Tribolium castaneum (Herbst), the red flour beetle, through direct and indirect sampling. J. Stored Prod. Res. 53: 1-6.
pdf icon PDF Buckman, K.A., and J.F. Campbell. 2013. How varying pest and trap densities affect Tribolium castaneum capture in pheromone traps. Entomol. Exp. Appl. 146: 404-412.
pdf icon PDF Buckman, K.A., J.F. Campbell, and B. Subramanyam. 2013. Tribolium castaneum (Coleoptera: Tenebrionidae) associated with rice mills: Fumigation efficacy and population rebound. J. Econ. Entomol. 106: 499-512.
pdf icon PDF Campbell, J.F. 2013. Influence of landscape pattern in flour residue amount and distribution on Tribolium castaneum (Herbst) response to traps baited with pheromone and kairomone. J. Stored Prod. Res. 52: 112-117.
pdf icon PDF Semeao, A.A., J.F. Campbell, J.M.S. Hutchinson, R.J. Whitworth and P.E. Sloderbeck. 2013. Spatio-temporal distribution of stored-product insects around food processing and storage facilities. Agric., Ecosyst. Environ. 165: 151-162.
pdf icon PDF Semeao, A.A., J.F. Campbell, R.J. Whitworth, and P.E. Sloderbeck. 2013. Movement of Tribolium castaneum within a flour mill. J. Stored Prod. Res. 54: 17-22.
pdf icon PDF Campbell, J.F. 2012. Attraction of walking Tribolium castaneum adults to traps. Environ. Entomol. 51: 11-22.
Campbell, J.F., J. Perez-Mendoza, and J. Weier. 2012. Insect pest management decisions in food processing facilities, p. 219-233. In Hagstrum, D.W., T.W. Phillips, and G. Cuperus (eds.). Stored Product Protection. Kansas State University S156, Manhattan, KS.
pdf icon PDF Cohnstaedt, L.W., K. Rochon, A.J. Duehl, J.F. Anderson, R. Barrera, N-Y. Su, A.C. Gerry, P.J. Obenauer, J.F. Campbell, T.J. Lysk, and S.A. Allan. 2012. Arthropod surveillance programs: Basic components, strategies, and analysis. Ann. Entomol. Soc. Am. 105: 135-149.
pdf icon PDF Flinn, P.W., and J.F. Campbell. 2012. Effects of flour conditioning on cannibalism of T. castaneum eggs and pupae. Environ. Entomol. 41: 1501-1504.
pdf icon PDF Semeao, A.A., J.F. Campbell, R.J. Whitworth, and P.E. Sloderbeck. 2012. Influence of environmental and physical factors on capture of Tribolium castaneum (Coleoptera: Tenebrionidae) in a flour mill. J. Econ. Entomol. 105: 686-702.
pdf icon PDF Semeo, A.A., J.F. Campbell, R.W. Beeman, M.D. Lorenzen, R.J. Whitworth, and P.E. Sloderbeck. 2012. Genetic structure of Tribolium castaneum (Coleoptera: Tenebrionidae) populations in mills. Environ. Entomol. 41: 188-199.
Article LinkShapiro-Ilan, D.I., E.E. Lewis, J.F. Campbell, and D.B. Kim-Shapiro. 2012. Directional movement of entomopathogenic nematodes in response to electrical field: effects of species, magnitude of voltage, and infective juvenile age. J. Invertebr. Pathol. 109: 34-40.
pdf icon PDF Arthur, F.H., E.A. Fontenot, and J.F. Campbell. 2011. Evaluation of catmint oil and hydrogenated catmint oil as repellents for the flour beetles, Tribolium castaneum and Tribolium confusum. J. Insect Sci. 11(128), 9 pp.
Campbell, J.F. 2011. Evaluation of factors impacting trap captures of red flour beetle, pp. 57-62. In Athanassiou, C.G., C. Adler, and P. Trematerra (eds.). Proceedings for the International Organization for Biological and Integrated Control of Noxious Animals and Plants West Palaearctic Region Section Working Group on Integrated Protection of Stored Products, June 29-July 2, 2009, Campobasso, Italy. IOBC/WPRS Bulletin 69.
pdf icon PDF Lu, Y., R.W. Beeman, J.F. Campbell, Y. Park, M.J. Aikins, K. Mori, K. Akasaka, S. Tamogami, and T.W. Phillips. 2011. Anatomical localization and stereoisomeric composition of Tribolium castaneum aggregation pheromones. Naturwissenschaften 98: 755-761.
pdf icon PDF Nachappa, P., D.C. Margolies, J.R. Nechols, and J.F. Campbell. 2011. Variation in predator foraging behaviour changes predator-prey spatio-temporal dynamics. Funct. Ecol. 25: 1309-1317.
pdf icon PDF Perez-Mendoza, J., J.F. Campbell, and J.E. Throne. 2011. Influence of age, mating status, sex, quantity of food, and long-term food deprivation on red flour beetle (Coleoptera: Tenebrionidae) flight initiation. J. Econ. Entomol. 104: 2078-2086.
pdf icon PDF Perez-Mendoza, J., J.F. Campbell, and J.E. Throne. 2011. Effects of rearing density, age, sex, and food deprivation on flight initiation of the red flour beetle (Coleoptera: Tenebrionidae). J. Econ. Entomol. 104: 433-451.
pdf icon PDF Semeao, A.A., J.C. Campbell, R.J. Whitworth, and P.E. Sloderbeck. 2011. Response of Tribolium castaneum and Tribolium confusum adults to vertical black shapes and its potential to improve trap capture. J. Stored Prod. Res. 47: 88-94.
pdf icon PDF Sutton, A.E., F.H. Arthur, K.Y. Zhu, J.F. Campbell, and L.W. Murray. 2011. Residual efficacy of synergized pyrethrin + methoprene aerosol against larvae of Tribolium castaneum and Tribolium confusum (Coleoptera: Tenebrionidae). J. Stored Prod. Res. 47: 399-406.
Show All Publications

* Indicates link to external site


Last Modified: 5/19/2014