Twenty-nine natural products and their derivatives were tested for both contact and vapor toxicity against the Formosan subterranean termite, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae). Five natural products at 0.5% (wt:wt) in petri dish contact assay caused 100% mortality within 3 d.
View Article and Find Full Text PDFAn endogenous cellulase gene (CfEG3a) of Coptotermes formosanus, an economically important pest termite, was cloned and overexpressed in both native form (nCfEG) and C-terminal His-tagged form (tCfEG) in Escherichia coli. Both forms of recombinant cellulases showed hydrolytic activity on cellulosic substrates. The nCfEG was more active and stable than tCfEG even though the latter could be purified to near homogeneity with a simple procedure.
View Article and Find Full Text PDFThe pyrokinin/pheromone-biosynthesis-activating neuropeptide (PBAN) family of peptides found in insects is characterized by a 5-amino-acid C-terminal sequence, FXPRLamide. The pentapeptide is the active core required for diverse physiological functions, including the stimulation of pheromone biosynthesis in female moths, muscle contraction, induction of embryonic diapause, melanization, acceleration of puparium formation, and termination of pupal diapause. We have used immunocytochemical techniques to demonstrate the presence of pyrokinin/PBAN-like peptides in the central nervous system of the fire ant, Solenopsis invicta.
View Article and Find Full Text PDFArthropod Struct Dev
November 2008
We report the discovery of a single-celled putative new gland associated with the retrocerebral complex in the adults of Helicoverpa zea. The gland was not observed in Manduca sexta and few other species of moths. The pair of glands, each 50.
View Article and Find Full Text PDFJ Insect Physiol
January 2008
The Formosan subterranean termite, Coptotermes formosanus, with its huge colonies, is a major urban pest in several southern states and Hawaii as well as in South Asia. Because of their cryptic nature (underground habitat) and very long life cycle, not much is known about molting in termite workers. In C.
View Article and Find Full Text PDFA gram-negative facultative anaerobic enteric bacterium, Klebsiella pneumoniae was isolated from the hindgut of the Formosan subterranean termite (FST). It was characterized using, fatty acid methyl ester (FAME) analysis, BIOLOG assay, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and biochemical studies. The role of this isolate seems to be nitrogen fixation because the termite's diet is nitrogen deficient and the isolate produced significant amounts of ammonia when it was grown on nitrogen deficient medium under anaerobic condition with nitrogen gas in the headspace.
View Article and Find Full Text PDFThe Formosan subterranean termite, Coptotermesformosanus Shiraki (Isoptera: Rhinotermitidae), accidentally brought into the United States, has become a major urban pest, causing damage to structures and live trees. Because of increasing restrictions on the use of conventional termiticides, attention is focused on finding safer alternative methods for termite management. Oil from citrus peel, referred to here as orange oil extract (OOE), contains -92% d-limonene, and it is generally known to be toxic to insects.
View Article and Find Full Text PDFJ Invertebr Pathol
October 2006
Hz-2V, formerly called gonad-specific virus, is known to infect the reproductive organs of both males and females of the corn earworm Helicoverpa zea, rendering them agonadal or sterile. The primary mode of transmission is through mating by asymptomatic carrier moths. In this report we show that Hz-2V can be acquired by first instar larvae, through feeding on virus laced diet, although the incidence of agonadal condition was significantly lower.
View Article and Find Full Text PDFAlates of the Formosan subterranean termite, Coptotermes formosanus Shiraki, collected after swarming in 2002 died within 48 h, and the cadavers were visibly infected with a fungus. Fungi were picked from the cadavers, transferred to media, and ultimately isolated to purity. The individual fungal cultures were then used to infect Formosan subterranean termite workers.
View Article and Find Full Text PDFIt has been suggested that hydroquinone found in the labial glands of a number of termite species acts as a primary phagostimulating factor. We tested hydroquinone as a phagostimulant using workers from three colonies of the Formosan subterranean termite, Coptotermes formosanus, under both laboratory and field conditions. Hydroquinone at concentrations ranging from ca.
View Article and Find Full Text PDFIn field collections of the Formosan subterranean termite Coptotermes formosanus, soldiers averaged less than 10%. The proportion of soldiers increased to about 25% or higher when termites were kept in the laboratory, as did the juvenile hormone III (JH III) titers for both workers and soldiers. In laboratory experiments with a proportion of soldiers 25% or higher, very few new pre-soldiers were formed and the JH titer in existing soldiers remained constant.
View Article and Find Full Text PDFIn most social insects, intercolonial and interspecific aggression are expressions of territoriality. In termites, cuticular hydrocarbons (CHCs) have been extensively studied for their role in nestmate recognition and aggressive discrimination of nonnest-mates. More recently, molecular genetic techniques have made it possible to determine relatedness between colonies and to investigate the influence of genetics on aggression.
View Article and Find Full Text PDFHexane extracts of the tergal glands from female alates of the Formosan subterranean termite Coptotermes formosanus were analyzed by high performance liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry with collision-induced dissociation. Double bond configuration was determined by chemical modifications with gas chromatography-mass spectrometry. A single component, identified as the triacylglycerol, trilinolein, was unique to the female tergal glands.
View Article and Find Full Text PDFJuvenile hormone (JH) is an important growth hormone in insects that has also been implicated in caste determination in termites. Gas chromatography-mass spectrometry was used to establish that the JH in the Formosan subterranean termite, Coptotermes formosanus Shiraki, is JH III. JH III titers were measured in workers, pre-soldiers, and soldiers from samples collected from the field.
View Article and Find Full Text PDFAfter swarming, reproductive dealates of the Formosan subterranean termite, Coptotermes formosanus, run together in tandem. The tandem running is an age-related behavioral activity in C. formosanus.
View Article and Find Full Text PDFFecundity, mortality, and food consumption of the Formosan subterranean termite, Coptotermes formosanus Shiraki, were evaluated in response to five plant flavonoids (genistein, biochanin A, apigenin, quercetin, and glyceollin). Apigenin fed at 50 microg/primary reproductive pair proved to be the most toxic flavonoid. Biochanin A was most effective in reducing fecundity.
View Article and Find Full Text PDFThe sequence of an 18-amino acid residue peptide was deduced from the gene encoding PBAN and other peptides with common C-termini in Helicoverpa zea. The peptide caused melanization in larvae and pheromone production in females of H. zea, and was designated pheromonotropic melanizing peptide (Hez-PMP).
View Article and Find Full Text PDFFollowing a short swarming flight, winged adults of the Formosan subterranean termite, Coptotermes formosanus lose their wings and form tandem pairs. These dealates or primary reproductives then form incipient colonies. Topical application of 5 microg of the non-steroidal ecdysone agonist RH-0345 (halofenozide) in 0.
View Article and Find Full Text PDFIn adult moths, the cephalic aorta terminates in an apical sack from which extends a pair of optic and antennal vessels that lie on either side of the esophagus, at the dorsoanterior surface of the brain. The base of each antennal vessel is dilated to form an ampulla that contains an oval mass of tissue, the antennal ampullary gland (AAG). An ultrastructural study revealed that the AAG of the corn earworm moth, Helicoverpa zea (Lepidoptera, Noctuidae), is composed of a single type of 40-50 parenchymal cells that produce secretory granules.
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