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The oviposition behavior of mosquitoes is mediated by chemical cues. In the malaria mosquito Anopheles gambiae, conspecific larvae produce infochemicals that affect this behavior. Emanations from first instar larvae proved strongly attractive to gravid females, while those from fourth instars caused oviposition deterrence, suggesting that larval developmental stage affected the oviposition choice of the female mosquito. We examined the nature of these chemicals by headspace collection of emanations of water in which larvae of different stages were developing. Four chemicals with putative effects on oviposition behavior were identified: dimethyldisulfide (DMDS) and dimethyltrisulfide (DMTS) were identified in emanations from water containing fourth instars; nonane and 2,4-pentanedione (2,4-PD) were identified in emanations from water containing both first and fourth instars. Dual-choice oviposition studies with these compounds were done in the laboratory and in semi-field experiments in Tanzania. In the laboratory, DMDS and DMTS were associated with oviposition-deterrent effects, while results with nonane and 2,4-PD were inconclusive. In further studies DMDS and DMTS evoked egg retention, while with nonane and 2,4-PD 88% and 100% of female mosquitoes, respectively, laid eggs. In dual-choice semi-field trials DMDS and DMTS caused oviposition deterrence, while nonane and 2,4-PD evoked attraction, inducing females to lay more eggs in bowls containing these compounds compared to the controls. We conclude that oviposition of An. gambiae is mediated by these four infochemicals associated with conspecific larvae, eliciting either attraction or deterrence. High levels of egg retention occurred when females were exposed to chemicals associated with fourth instar larvae. Electronic supplementary material The online version of this article (10.1007/s10886-020-01175-5) contains supplementary material, which is available to authorized users.

Background The public's negative attitudes towards household insects drive tolerance for these insects and their control. Tolerance levels are important in integrated pest management (IPM), as are pest knowledge and information. The risk information seeking and processing (RISP) model describes the relationships between personal factors and information-seeking behaviour. We combined IPM and RISP to determine important relationships between factors driving insect tolerance levels and information-seeking behaviour through an online survey and tested whether this model is valid and generally applicable. Results Relationships between variables from both IPM and RISP models were tested for seven insect species. Tolerance levels were measured with two factors: willingness to pay for pest control and whether insects are tolerated. Willingness to pay for control was positively affected by age, experience, risk perception, insect characteristics, and negative emotions and affected behavioural intention, by influencing information sufficiency and information-seeking behaviour. Tolerability was influenced by perception of insect characteristics and determines whether control measures are taken. Conclusion It was possible to combine the RISP and IPM models. Relevant driving factors were a person's age, experience, risk perception, negative affective responses, tolerance levels, relevant channel beliefs about online forums, information sufficiency and information-seeking behaviour. There was, however, variation in important factors between different insects. © 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Households are mini-ecosystems that provide a variety of conditions in which a variety of insect species can develop. Whether these insects are considered pests, largely depends on the perception, attitudes, and knowledge of the human inhabitants of the house. If considered unacceptable, residents can attempt to manage the insects themselves, or hire a professional. A pest management professional can provide a quick-fix solution, often relying on the sole use of insecticides, or a sustainable solution through integrated pest management (IPM). In this review, it is discussed how the public's perception, attitudes, and knowledge affect the implementation of IPM in the household through the following steps: inspection, identification, establishment of a threshold level, pest control, and evaluation of effectiveness. Furthermore, recent and novel developments within the fields of inspection, identification, and pest control that allow to address pest infestations more effectively are described and their implementation in the household environment is discussed. In general, pest management in the household environment is reactive instead of pro-active. The general public lacks the knowledge of the pest insects’ biology to identify the species, perform a proper inspection and identify causes of pest presence, as well as the knowledge of the available tools for monitoring and pest control. The percentage of individuals that seek professional aid in identification and pest control is relatively low. Moreover, the perception of and attitudes towards household insects generally result in low threshold levels. Current developments of methods for monitoring, identification, and control of insect pests in the household environment are promising, such as DNA barcoding, matrix-assisted laser desorption/ionization time-of-flight and RNA interference. Efforts should be strengthened to alter the perception and attitude, and increase the knowledge of the non-professional stakeholders, so that correct pest management decisions can be taken.

BACKGROUND Rodenticide resistance to anticoagulants in Rattus norvegicus will lead to increased difficulties in combating these pest animals. Here, the authors present the results of a survey in the Netherlands where tissue samples and droppings were tested using a newly developed TaqMan PCR test for genotypic variation at codon 139 in the Vkorc1 gene associated with anticoagulant rodenticide resistance. Test results are linked to results of a questionnaire that was conducted among pest controllers. RESULTS Genetic mutations at codon 139 of the Vkorc1 gene in R. norvegicus can be encountered in many parts of the Netherlands. In 34/61 rat tails, a genotype was found that is linked to anticoagulant rodenticide resistance (56%). In droppings, 42/169 samples (25%) showed a resistance-mediating genotype. In addition, indications of a clear genetic substructure in the Netherlands were found. In some regions, only resistance-mediating genotypes were found, corroborating results from the questionnaire in which pest controllers indicated they suspected resistance to anticoagulant rodenticides. CONCLUSION This is the first study to demonstrate the presence of multiple genetic mutations at codon 139 of the Vkorc1 gene in R. norvegicus in the Netherlands. As rodenticides should keep their efficacy because they are a last resort in rodent management, more studies are urgently needed that link specific genetic mutations to the efficacy of active substances. © 2014 Society of Chemical Industry