Amplification of the genes coding for ribosomal RNA oocurs in the oocytes of a wide variety of organisms. In oocytes of various species of crickets (Orthoptera: Gryllidae) the amplified DNA is contained in a large extrachromosomal DNA body. Multiple nucleoli form about the periphery of the DNA body during the diplotene stage of meiosis I. In contrast to the general pattern of orthopteran oocyte...

The insecticidal activity of a cockroach gel bait containing a chitin synthesis inhibitor, noviflumuron, was evaluated using laboratory and field strains of the German cockroach, Blattella germanica (L.). Noviflumuron gel bait (0.01-5 mg g(-1)) caused > or = 90% nymphal mortality to laboratory and field strains of B. germanica in choice tests after 11 and 19 days of continuous exposure respecti...

AIM To evaluate German cockroach (Blattella germanica) allergen levels in house dust and skin reactivity to German cockroach in adult atopic and non-atopic subjects in inland areas of Croatia. METHODS Blattella germanica group 2 (Bla g 2) allergen was measured using the enzyme-linked immunosorbent assay (ELISA) on test strips (Dustscreen(TM) test, Heska AG, Switzerland) in 94 house dust sampl...

Cockroaches have been regarded as possible vectors of human enteropathogens. Their presence and crawl particularly in food handling establishments could be risky for human health. Therefore, this study was done to determine the vector potential of cockroach for medically important bacterial pathogens in restaurants and cafeterias. A cross-sectional study was conducted on cockroaches from restau...

Juvenile hormone III biosynthesis in vitro by the corpora allata of adult female Bluttellu germanica is precisely correlated with the gonotrophic cycle. Farnesoic acid-stimulated rates of juvenile hormone synthesis are always higher than the corresponding basal rates, and follow the same pattern of cyclic changes during oijcyte maturation. Both basal and farnesoic acid-stimulated rates decline ...

Glucose-averse (Glu/Glu) male German cockroaches, Blattella germanica, rejected brief exposures to glucose solutions despite food deprivation so extreme as to cause high mortality. In the 24-h period following 5 days of food deprivation, both Glu/Glu and wild-type (+/+) were given a continuous source of 1 M glucose solution. Although Glu/Glu visited the solution as frequently as +/ + , feeding ...

YXFGL-NH(2) family allatostatins (ASTs) were isolated from cockroach brain extracts based on their capacity to inhibit juvenile hormone (JH) biosynthesis in corpora allata (CA) incubated in vitro. Subsequently, the inhibitory activity of synthetic ASTs was demonstrated experimentally, although these peptides were shown to be active as JH inhibitors only in cockroaches, crickets, and termites. H...

Studies on the population and infestation rates of domestic cockroaches were conducted from September 1999 to October 2000 in 154 residences in 21 districts (dong) in Busan and 170 residences in 12 districts in Seoul, Republic of Korea, using sticky traps. Blattella germanica, Periplaneta americana and Periplaneta fuliginosa were collected from three different types of houses, apartments, singl...

The interspecific competition between a new cockroach pest species in Southeast Asia, the Smooth cockroach, Symploce pallens (Stephens) and the ubiquitous German cockroach, Blattella germanica (L.) was studied under different food and water regimes (unlimited food and water [control], limited water, limited food and limited food and water). Both species were found to have equal chances to coexi...