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A study was conducted to investigate the population genetic structure and breeding pattern of 140 tropical bed bugs, Cimex hemipterus (F.) (Hemiptera: Cimicidae), collected from 14 infested sites in major cities in Iraq. The samples were genotyped using a set of 7 polymorphic microsatellite markers. High genetic variety was seen among populations, with an average of 2–9 alleles per locus. The number of alleles across 7 microsatellite loci was between 6 and 18. There was a notable disparity in the alleles per loci when comparing the overall population to those within it. The overall population exhibited an average observed heterozygosity of 0.175 and an average expected heterozygosity of 0.730. Among the population, the average observed heterozygosity was 0.173, while the average expected heterozygosity was 0.673. Analysis of molecular variance (AMOVA) revealed that 93% of the genetic variability was within the populations, and 7% was among them. The genetic differentiation coefficient (F ST = 0.045), indicates a low degree of genetic differentiation and a high degree of inbreeding (F IS = 0.761), as indicated by notably significant positive inbreeding coefficients. Admixed individuals were revealed using STRUCTURE and neighbor-joining phylogenetic trees, demonstrating moderate gene flow between populations and a lack of genetic structure in the regional groups. Thus, both active dispersion and human-mediated dispersion possess the potential to influence the low population genetic structure of tropical bed bug C. hemipterus populations in Iraq, which can have implications toward tropical bed bug and management strategies. [ABSTRACT FROM AUTHOR]

Background: Bed bugs are blood-feeding insects and are an important urban pest. Bed bugs are nocturnal insects and hide in cracks in walls and beds during the day. The study aims to: (1) determine the bed bugs species that infest Iraq, their infestation source, and their distribution; (2) determine the level of awareness and concern regarding bed bugs among the Iraqi community. Methods: Between 2020 and 2021, a survey of bed bug infestation dynamics was conducted in 18 infested sites located in major cities across eight governorates. The 23-item online survey was distributed over social media to Iraqi citizens between June and July 2022 to survey on their familiarity with bed bug habitat, medical significance, transmission, prevention, control measures, and concerns. Results: There were a total of 1104 bed bugs collected. Based on the morphological characteristics, bed bugs collected from eight Iraqi governorates are identified as Cimex hemipterus. Besides, a high rate of bed bug infestation was observed in workers' dormitories. The online questionnaire was answered by 1843 respondents and based on the feedback, most respondents (55.3%) have no awareness of bed bug infestations, while around 43.8% are somewhat concerned about bed bug infestations in Iraq. Conclusion: Only tropical bed bugs, C. hemipterus were found in all sampled sites. Bed bug infestations are mainly caused by migrant workers and the reuse of second-hand furniture and clothing. The results suggest that the Iraqi government should organize more proper demonstrations on bed bug awareness for the public. [ABSTRACT FROM AUTHOR]

The uptake of silicon ( Si) by plants is known to reinforce plant tissues against invertebrate herbivores, but whether there is also direct antibiosis from ingesting Si remains in question. To investigate for antibiotic effects, Si-bearing minerals, wollastonite ( CaSiO3) or olivine ( Mg/FeSiO3), were added to artificial diets as finely ground powders (40-50 μm) before or after acidulation to determine whether Si-reduced larval growth. Newly hatched H elicoverpa armigera ( Hübner, 1808) and H . punctigera ( Wallengren, 1860) ( Lepidoptera: Noctuidae) were placed onto the diets and weighed once the larvae on the control diet had completed feeding (day12 for H . armigera; day 14 for H . punctigera: 25.5° C). Acidulated olivine at rates of 0.4-1.7% Si w/dw (weight Si/dry weight of diet) reduced larval weight of H . armigera by 95-99% compared with control diets. Non-acidulated olivine also appeared to cause a decline in larval weight. Wollastonite at rates of up to 3.3% Si had no significant effect on larval weight whether acidulated or not. A similar effect was observed for H . punctigera. Very few insects survived to emergence on diets containing the higher rates of acidulated olivine. Olivine contains quantities of heavy metals, particularly nickel, cobalt and chromium, which can be toxic to insects. Given the lack of toxicity when Si was included as wollastonite compared with similar quantities as olivine, the heavy metals are implicated as the antibiotic agents. Acidulation increased the toxicity of olivine probably by rendering the metals more biologically active. The results of this bioassay do not support the hypothesis that Si is directly antibiotic to H elicoverpa spp. via ingestion. [ABSTRACT FROM AUTHOR]