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...

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...

Development of nymphs and oocyte maturation in adults were examined in Blattella germanica (L.) reared on three commercial diets. Nymphs fed rat food developed significantly faster than nymphs fed two commercial dog foods. Similarly, oocytes matured more quickly in adult females that were raised on rat food than in females raised on dog food. Nymphal development and oocyte maturation were slowe...

Insect metamorphosis is regulated by ecdysteroids, which induce molts, and juvenile hormone (JH), which inhibits metamorphic changes. The molecular action of ecdysteroids has been thoroughly studied, but that of JH is poorly understood, with data currently only being available for holometabolous species, like Drosophila melanogaster and Tribolium castaneum. We studied the function of Krüppel ho...

In Blattella germanica, the German roach or "croton bug," bacteriocytes are found in all individuals of both sexes. These bacteriocytes are scattered throughout the fat tissue and their cytoplasm is filled with microorganisms. Evidence is presented to show that the intracellular parasites are diphtheroidal bacilli. These diphtheroids are transmitted from one generation to another through the ov...