Studies to determine the effects of gamma-radiation on sex pheromone production in female Tenebtio molitor showed that irradiation of females either as newly emerged or as pharate adults with 3.5 or 7 krad had no significant effect on their sex pheromone activity when compared to that of normals. However, treatment of irradiated insects with a juvenile hormone analogue increased their pheromone...

The flounder, Platichthys flesus, is the most abundant flatfish species in the northern Baltic Sea. Juvenile P. flesus are important epibenthic predators on shallow sandy bottoms in this area, and play an important role in structuring benthic infaunal communities by both lethal and sublethal predation. These areas are affected by periodic oxygen deficiency during summer and autumn when drifting...

Last instar larvae of S. mauritia treated topically on day 0, day 1, day 2 and day 3 with a daily (dose of 25 microg juvenile hormone analogue (JHA) moulted into supernumerary larvae. The imaginal discs of the supernumerary larvae especially those of mouthparts and thoracic appendages showed pupal characteristics. However the wing discs, which showed only partial differentiation, were uneverted...

BACKGROUND Juvenile hormone (JH) plays an important role in honeybee development and the regulation of age-related division of labor. However, honeybees can be exposed to insect growth regulators (IGRs), such as JH analogs developed for insect pest and vector control. Although their side effects as endocrine disruptors on honeybee larval or adult stages have been studied, little is known about ...

the beet armyworm (spodoptera exigua hübner) is an important pest of many agricultural crops all over the world. most of the sugar beet growing regions in iran are infested. in this study, the acute lethal effects of pyriproxyfen, spinosad, and indoxacarb as well as sublethal effects of pyriproxyfen on the 1st instar s. exigua were assessed by leaf dip bioassay method. mortality was recorded 48...

Exploring the possibility of enhancing the properties of baculoviruses as biological control agents of insect pests, we tested the effect of expressing an insect gene (jhe) encoding juvenile hormone esterase. Juvenile hormone esterase inactivates juvenile hormone, which regulates the outcome of an insect molt. A cDNA encoding the juvenile hormone esterase of Heliothis virescens was inserted int...

The Gram-positive bacterium, Bacillus stearothermophilus, was used as a model organism to identify the non-selective toxic effects of the currently used insecticide methoprene (isopropyl(2E,4E)-11-methoxy-3,7,11-trimethyl-2,4-dodecadienoate). A significant decrease of the yield of bacterial cultures and a premature appearance of ultrastructural abnormalities in cells cultured in the presence of...

We have used differential display to identify genes that are regulated by juvenile hormone in the epidermis of the beetle Tenebrio molitor. One of the genes encodes T. molitor chitinase 5 (TmChit5), a chitinase possessing an unusual structure. Sequence analysis of TmChit5 identified five 'chitinase units' of approx. 480 amino acids with similarity to chitinase family 18. These units are separat...