Residence 
Location 
Progress 10/01/08 to 09/30/14
OutputsTarget Audience: The audience for this research includes researchers at other institutions, the chemical industry, pest management professionals, and the public. Changes/Problems:Nothing ReportedWhat opportunities for training and professional development has the project provided? Three graduate students have participated in this project. How have the results been disseminated to communities of interest? Peer reviewed publications, trade journal articles, presentations at meetings What do you plan to do during the next reporting period to accomplish the goals?Nothing Reported
ImpactsWhat was accomplished under these goals? . Ten field populations of bed bugs varied in their senstivity toTemprid and Transport, both are products containing a neonicotinoid and a pyrethroid. Temprid selection on three populations of bed bugs resulted in significant decreases in susceptibility to this insecticide in the subsequent generation. This selection also resulted in an increase in resistance levels to Transport. Silica gel is an effective desiccant dust. Brief exposure of bed bugs to the label rate of this dust resulted in high mortality 24 h after exposure. A survey of the pest control industry indicated a continuing need for innovations in pest management options for bed bug control. Bed bugs are consistently rated as the most difficult urban insect pest to manage. Over the course of this project we made the following findings: 1. Pyrethroid resistance is widespread; 2. Pyrethroid resistance is mediated by diverse mechanisms in different populations; 3. Phantom is a slow, but effective insecticide; 4. Harborage-seeking and host-finding behaviors are not interrupted by the presence of deltamethrin or chlorfenapyr; 4. Nightly cycles of activity in bed bugs are mediated by a circadian rhythm; 5. The sensitivity of humans to bed bug bites varies considerably; 6. P450 enzymes are involved in pyrethroid resistance. 7. The growth regulator, Gentrol, is only effective in disrupting reproduction at exposure rates above the label rate; and 8. The hooked trichomes of kidney bean plants are a model for the development of traps that could be useful in monitoring;
Publications
Progress 01/01/13 to 09/30/13
OutputsTarget Audience: Scientists, Pest management professionals, the Public Changes/Problems:Nothing ReportedWhat opportunities for training and professional development has the project provided?Nothing ReportedHow have the results been disseminated to communities of interest? Publications, presentations, seminars What do you plan to do during the next reporting period to accomplish the goals?Nothing Reported
ImpactsWhat was accomplished under these goals? Pyrethroid resistance in bed bugs,Cimex lectularius, has prompted a change to combination products thatinclude a pyrethroid and a neonicotinoid. Ten populations of bed bugs were challenged with two combination products (Temprid SC®and Transport GHP®). Susceptibility of these populations varied, with the correlated response of the two products indicating cross resistance. We imposed selection on three populations using label rate Temprid, and then reared progeny from unselected and selected strains. All selected strains were significantly less susceptible to Temprid SC than unselected strains. Temprid selected strains were also less susceptible to Transport. The pyrethroid component of Temprid showed a significantly higher LD50in selected strains, but susceptibility to the neonicotinoid remained unchanged. Taken together these results indicate resistance to combination insecticides is present in field populations at levels that should be of concern, and that short-term selection affecting existing variance in susceptibility can quickly increase resistance.
Publications
Progress 01/01/12 to 12/31/12
OutputsOUTPUTS: Bed bugs have a severe impact on the quality of life that is exacerbated by the difficulty that is faced in eliminating their populations. Part of this difficulty is a result of their stealthy feeding habits, where they remain hidden from view except during brief excursions to get a blood meal. We have found that immature bed bugs are more efficient in finding food when their mothers are present. The communication mechanism for this maternal care is under investigation. This facilitation of host finding is likely to play an important role in enabling very small immature bed bugs to develop when to blood meal is located at a distance. It is difficult for pest control operators to deliver insecticides to hiding places. We have found widespread resistance to pyrethroid insecticides, which has prompted switches to insecticides with different modes of action. Pyrethroid and neonicitinoid combination products proved to have laboratory efficacy against pyrethroid resistant populations. However, selection for resistance to a dual action insecticide resulted in a change in susceptibility within one generation in two populations of bed bugs. This evolution involves multiple mechanisms of resistance, including up-regulation of cuticular proteins, P450 enzymes, carboxyl esterases, and transporter proteins. A growth regulating hormone analog (Gentrol) was found to be effective in curtailing bed bug reproduction only at very high application rates. Thus this environmentally benign insecticide is not a standalone product for bed bug control. PARTICIPANTS: Michael F. Potter, Scottt Bessin, Jennifer Gordon, Mark Goodman ,Kyle Loughlin, Shelby Stamper, Sydney Crawley TARGET AUDIENCES: Not relevant to this project. PROJECT MODIFICATIONS: Not relevant to this project.
ImpactsBecause insecticide resistance to combination products (neonicitinoid with pyrethroid) occurs in the laboratory, it should be a concern for the future of bed bug pest management. Gentrol is not a standalone product at label rates.
Publications
Progress 01/01/11 to 12/31/11
OutputsOUTPUTS: We continued our investigation of the role of bacterial endosymbionts in bed bug biology. Near elimination of Wolbachia did not have a major impact on bed bug reproduction. We began a laboratory investigation of the potential for evolution of resistance to combination insecticides (including a pyrethroid and a neonicotinoid) for bed bug control. We observed a response to selection in one generation, indicating that there is heritable variation in our laboratory colonies with respect to the impact of these insecticides. We began a study of the impact of insect repellents on bed bug behavior. Some of the commercially available products showed promise in preventing bed bugs from seeking refuge on treated surfaces. We investigated the impact of one insect growth regulator on bed bug development and reproduction. Gentrol showed marked effects on reproduction, but only at high application rates (above the label rate). PARTICIPANTS: Michael F. Potter, Scottt Bessin,Jennifer Gordon, Mark Goodman,Kyle Loughlin, Shelby Stamper TARGET AUDIENCES: Not relevant to this project. PROJECT MODIFICATIONS: Not relevant to this project.
ImpactsBecause pest management professionals have few insecticidal options, they must be cognizant of the potential for resistance to combination products that have thus far proven to be efficacious.
Publications
Progress 01/01/10 to 12/31/10
OutputsOUTPUTS: Infestations of the bed bug are increasing around the world at an alarming rate and have become a major public health concern. Because resistance to pyrethroid insecticides is widespread in the U.S. there is a great demand for novel approaches for pest control, and a renewed effort to learn characteristics of bed bug behavior. Bed bugs must avoid detection when finding hosts and returning to hidden harborages. Their stealthy habits include foraging when hosts are asleep. Characteristics of locomotor activity rhythm of bed bugs with different feeding history were studied. In the absence of host stimuli, adults and nymphs were much more active in the dark than in the light. The onset of activity in the scotophase commenced soon after lights-off. The free-running period for all stages was longer in continuous darkness (DD) than in continuous light (LL). The lengthening of the free-running period in DD is an exception for the circadian rule that predicts the opposite in nocturnal animals. Activity in adults and nymphs was entrained to reverse L:D regimes within four cycles. Short-term starved adults moved more frequently than recently fed adults. While bed bugs can survive for a year or more without a blood meal, we observed a reduction in activity in insects held for five-weeks without food. We suggest that bed bugs make a transition to host-stimulus dependent searching when host presence is not predictable. Such a strategy would enable bed bugs to maximize reproduction when resources are abundant and save energy when resources are scarce. The presence of bed bug populations resistant to pyrethroids demands the development of new control tactics, including the use of insecticides with new modes of action. Insecticides that disrupt oxidative phosphorylation in insects' mitochondria can be an option. We measured with laboratory assays the toxicity of chlorfenapyr to susceptible strains and two strains highly resistant to pyrethroids. We also compared the effectiveness of two chlorfenapyr-based formulations and evaluated the behavioral responses of bed bugs to dry residues of aerosol sprays. Chlorfenapyr was effective against all bed bug strains, killing them at a similar rate, regardless of their susceptibility status to pyrethroids. Dry residues aged for four months were as toxic as fresh dry residues. The aerosol formulation had contact activity and caused a faster mortality than a water-based formulation. Bed bugs did not avoid resting on surfaces treated with aerosol. Chlorfenapyr is an option for controlling pyrethroid-resistant bed bugs. While it does not cause quick knockdown, long residual activity and no avoidance behavior of bed bugs to dry residues appears to make this insecticide suitable for bed bug control. A faster insecticidal effect is obtained with the aerosol formulation, suggesting greater bioavailablity of the toxicant. PARTICIPANTS: Nothing significant to report during this reporting period. TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
ImpactsChlorfenapyr has become an increasingly important option in bed bug control programs.
Publications
Progress 01/01/09 to 12/31/09
OutputsOUTPUTS: Infestations of the bed bug are increasing around the world at an alarming rate and have become a major public health concern. Because resistance to pyrethroid insecticides is widespread in the U.S. there is a great demand for novel approaches for pest control. An understanding of the mechanisms of insecticide resistance in the bed bug has the potential to lead to new approaches for the control of resistant populations. We used the P450 enzyme inhibitor piperonyl butoxide (PBO) to determine the role of detoxifying enzymes in deltamethrin resistance in three field-collected strains. We found that while PBO reduced the lethal dose required to kill 50% of each strain, residual resistance compared to a susceptible strain remained. The behavioral responses of bed bugs to deltamethrin (a pyrethroid), and chlorfenapyr (a pyrrole), two commonly used insecticides for bed bug control in the US were evaluated. In two-choice tests, grouped insects and individual insects avoided resting on filter paper treated with deltamethrin. Insects did not avoid surfaces treated with chlorfenapyr. Harborages, containing feces and eggs, and treated with a deltamethrin-based product, remained attractive to individuals from a strain resistant to pyrethroids. Insecticide barriers of chlorfenapyr or deltamethrin did not prevent bed bugs from reaching a warmed blood source and acquiring blood meals. We tested five different dusts representing two insecticide categories: two pyrethroid-based dusts, and three desiccant dusts. Both types were effective in killing bed bugs, even from a resistant strain. PARTICIPANTS: Michael Potter (Extension Faculty) and Alvaro Romero (graduate student) contributed to this research. TARGET AUDIENCES: Not relevant to this project. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
ImpactsSynergists such as piperonyl butoxide, insecticides with novel modes of action such as chlorfenapyr, and dusts have the potential to contribute to management of pyrethroid-resistant bed bugs.
Publications
Progress 01/01/08 to 12/31/08
OutputsOUTPUTS: The recent resurgence of bed bugs, Cimex lectularius L. (Heteroptera: Cimicidae), has increased the demand for information about effective control tactics. Several studies have focused on determining the susceptibility of bed bug populations to insecticides. However, behavioral responses of bed bugs to insecticide residues could influence their efficacy. The behavioral responses of bed bugs to deltamethrin, and chlorfenapyr, two commonly used insecticides for bed bug control in the US were evaluated. In two-choice tests, grouped insects and individual insects avoided resting on filter paper treated with deltamethrin. Insects did not avoid surfaces treated with chlorfenapyr. Harborages, containing feces and eggs, and treated with a deltamethrin-based product, remained attractive to individuals from a strain resistant to pyrethroids. Video recordings of bed bugs indicated that insects increased activity when they contacted sublethal doses of deltamethrin. Insecticide barriers of chlorfenapyr or deltamethrin did not prevent bed bugs from reaching a warmed blood source and acquiring blood meals. PARTICIPANTS: Michael Potter was a collaborator on this research. Alvaro Romero and Rebekah Hassell are conducting graduate studies that relate to this project. TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
ImpactsSurvival of bed bugs after their contact with pyrethoid residues, with the subsequent increase in locomotor activity, represents a potential problem for the spread of bed bugs to adjoining areas. This concern may be alleviated by bed bug produced aggregation factors that overcome this irritancy/repellency.
Publications
Read more:
Bed Bug Biology and Behavior - UNIVERSITY OF KENTUCKY
