Fitness-related costs of evolving insecticide resistance have been reported in a number of insect species, but the interplay between evolutionary adaptation to insecticide pressure and variable environmental conditions has received little attention. We provisioned nymphs from three German cockroach (Blattella germanica L.) populations, which differed in insecticide resistance, with either nutri...

German cockroaches (GCRs), Blattella germanica (L.) (Dictyoptera: Blattellidae), are attracted to those beer semiochemicals (e.g., ethanol) that formerly living and active yeasts have produced or otherwise formed in the brewing process. We predicted that an earlier step in the production of beer, where yeasts actively metabolize the sugar in malted barley powder (dry malt extract [DME]), is ver...

The Asian cockroach (Blattella asahinai Mizukubo) was introduced to Florida in 1986 and has since spread throughout the Southeastern United States. Blattella asahinai is a peridomestic pest and high population densities in residential areas can become a nuisance, especially when adults fly into homes. Few studies to date have been conducted on Asian cockroach control, and we evaluated the effic...

Twelve strains of German cockroach, Blattella germanica (Linnaeus) were collected from various locations in Peninsular Malaysia and tested for their susceptibility to three groups of insecticides applied topically. The levels of resistance were low to high (2.8 to 92×) for carbamates (propoxur and bendiocarb), low (2.0 to 7.6×) for organophosphate (chlorpyrifos) and low to moderate (1.0 to 23×)...

J. Econ. Enlomol. 79: 1613-1616 (1986) ABSTRACT Blattella germanica (L.) males succumbed to two consecutive sublethal doses of hydramethylnon (an amidinohydrazone) spaced up to 6 days apart. The same effect was not observed with a carbamate (propoxur) or organophosphate (chlorpyrifos) insecticide. Radiotracer analysis revealed presence of HCresidues inside cockroaches for at least 21 days follo...

Adaptations to hazardous environmental factors are essential for survival, although they may be maladaptive in conditions where the hazard is absent. In German cockroach (Blattella germanica L.) populations, glucose aversion has evolved rapidly in response to glucose-containing insecticidal baits, but little is known about the consequences of this behaviour in the absence of bait. In the presen...

BACKGROUND Cockroaches are among the medically important pests found within the human habitations that cause serious public health problems. They may harbor a number of pathogenic bacteria on the external surface with antibiotic resistance. Hence, they are regarded as major microbial vectors. This study investigates the prevalence and antibiotic resistance of Gram-negative pathogenic bacteria s...

Cockroach surveys using sticky traps were conducted in urban areas of 14 Thailand provinces. At least 30 houses in each province were randomly sampled for cockroaches. Each house was trapped in three areas: kitchen, bedroom and outside. A total of 2,648 cockroaches was caught by 550 out of 1,542 traps (35.7%), from 337 of the 514 houses (65.6%). Overall, relative density ranged from 2.6 to 9.1 ...

INTRODUCTION American cockroaches, Periplaneta americana, are the most important pests in hospitals and dwelling environments. They are mechanical vectors of some bacterial pathogens. GOAL The present investigation was carried out in Ghods hospital and 5 dwelling localities of Paveh city to evaluate bacterial infestations of American cockroaches in this region of Iran. METHODS The samples w...