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S. O. Appiah - One of the best experts on this subject based on the ideXlab platform.
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Uscana lariophaga, West-African egg parasitoid of the cowpea bruchid beetle Callosobruchus maculatus photoperiod, parasitization and eclosion interactions.
Entomologia Experimentalis Et Applicata, 1995Co-Authors: A. Huis, S. O. AppiahAbstract:The diurnal pattern of parasitization and eclosion of the trichogrammatid Uscana lariophaga Steffan, egg parasitoid of the cowpea bruchid Callosobruchus maculatus (Fabricius) was studied for L12:D12 photoperiods. The wasp parasitized eggs throughout each 24-h period with about 70% of the parasitization taking place during the first 12 h regardless whether it was the photophase or the Scotophase. More female progeny was produced when the first 12-h period was photophase instead of Scotophase. Eclosion of wasps took place over a period of 4 days and occurred during the second half of the Scotophase and the first half of the photophase. The number of wasps eclosed during the photophase was similar to that eclosed during the Scotophase. Average development time was 8.9 days at 30° C. Male development was completed 6 to 8 h before the females, hence a higher percentage of females emerged in the later eclosion peaks. During Scotophases more females eclosed than during photophases. Although the results indicate that the wasp is able to perform under dark storage conditions the effect of permanent low light intensity remains to be studied.
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Uscana lariophaga, West-African egg parasitoid of the cowpea bruchid beetleCallosobruchus maculatus: photoperiod, parasitization and eclosion interactions
Entomologia Experimentalis et Applicata, 1995Co-Authors: A. Huis, S. O. AppiahAbstract:The diurnal pattern of parasitization and eclosion of the trichogrammatid Uscana lariophaga Steffan, egg parasitoid of the cowpea bruchid Callosobruchus maculatus (Fabricius) was studied for L12:D12 photoperiods. The wasp parasitized eggs throughout each 24-h period with about 70% of the parasitization taking place during the first 12 h regardless whether it was the photophase or the Scotophase. More female progeny was produced when the first 12-h period was photophase instead of Scotophase. Eclosion of wasps took place over a period of 4 days and occurred during the second half of the Scotophase and the first half of the photophase. The number of wasps eclosed during the photophase was similar to that eclosed during the Scotophase. Average development time was 8.9 days at 30°C. Male development was completed 6 to 8 h before the females, hence a higher percentage of females emerged in the later eclosion peaks. During Scotophases more females eclosed than during photophases. Although the results indicate that the wasp is able to perform under dark storage conditions the effect of permanent low light intensity remains to be studied.
B. E. Mazomenos - One of the best experts on this subject based on the ideXlab platform.
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Mating behaviour of the corn stalk borerSesamia nnonagrioides
Entomologia Experimentalis et Applicata, 1992Co-Authors: N. A. Babilis, B. E. MazomenosAbstract:The mating behaviour of the corn stalk borer Sesamia nonagrioides (Lef.) [Lepidoptera:Noctuidae] was studied under laboratory conditions at 25 ± 1 °C, 65 ± 5% r.h. and 16:8 (L:D) regime. The females began calling during the first Scotophase following emergence, the peak of calling occurred during the second Scotophase and thereafter decreased. Maximum calling was observed between the fourth and sixth hour of the Scotophase. The calling pattern varied with age. During the first and second Scotophase most of the females were calling continuously, while during the third and fourth Scotophase periodic calling was observed. The mean onset of calling was advanced and the mean length of calling per day was increased slightly as the female became older. Females held for 72 h in continuous darkness exhibited an endogenous circadian rhythm of calling. Matings began during the first Scotophase following emergence and the peak of mating was observed during the second Scotophase. Mated females did not remate. Few males mated more than once during the following Scotophases.
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Pheromone production in Sesamia nonagrioides: Diel periodicity and effect of age and mating
Journal of Insect Physiology, 1992Co-Authors: N. A. Babilis, B. E. MazomenosAbstract:Abstract Diel periodicity of pheromone production and the effect of age and mating on the pheromone titre of the female Sesamia nonagrioides (Lef.) was studied. The pheromone titre was measured by quantitative capillary gas chromatographic analysis. Females began producing pheromone 20–24 h following emergence. The higher quantity of pheromone was measured during the second Scotophase. The pheromone gland contained detectable quantities 2 h after the onset of the Scotophase and reached maximal levels during the sixth hour in the second Scotophase. The pheromone titre was very low 2 h after the onset of the photoperiod. Females began calling 4 h after the onset of the Scotophase and peak calling activity was observed at the sixth hour. Mating suppressed pheromone biosynthesis. The quantity of pheromone measured in mated females 24, 48 and 72 h after mating was significantly lower than that of virgin females of similar age.
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Mating behaviour of the corn stalk borer Sesamia nonagrioides.
Entomologia Experimentalis Et Applicata, 1992Co-Authors: N. A. Babilis, B. E. MazomenosAbstract:The mating behaviour of the corn stalk borer Sesamia nonagrioides (Lef.) [Lepidoptera: Noctuidae] was studied under laboratory conditions at 25 ± 1 ° C, 65 ± 5 % r.h. and 16:8 (L:D) regime. The females began calling during the first Scotophase following emergence, the peak of calling occurred during the second Scotophase and thereafter decreased. Maximum calling was observed between the fourth and sixth hour of the Scotophase. The calling pattern varied with age. During the first and second Scotophase most of the females were calling continuously, while during the third and fourth Scotophase periodic calling was observed. The mean onset of calling was advanced and the mean length of calling per day was increased slightly as the female became older. Females held for 72 h in continuous darkness exhibited an endogenous circadian rhythm of calling. Matings began during the first Scotophase following emergence and the peak of mating was observed during the second Scotophase. Mated females did not remate. Few males mated more than once during the following Scotophases.
Wendell L. Roelofs - One of the best experts on this subject based on the ideXlab platform.
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Evidence for the presence of a pheromonotropic factor in hemolymph and regulation of sex pheromone production in Helicoverpa zea
Journal of Insect Physiology, 1995Co-Authors: Sonny B. Ramaswamy, Russell A. Jurenka, Charles E. Linn, Wendell L. RoelofsAbstract:Abstract In intact animal assays, 2-day-old females of Helicoverpa zea injected with 2 pmol synthetic H. zea-pheromone biosynthesis activating neuropeptide (Hez-PBAN) exhibited significant stimulation of pheromone production. In contrast, octopamine did not stimulate pheromone production when injected 30 min before lights off. Additionally, females injected with PBAN and mianserin (an octopamine antagonist) or reserpine, produced significant amounts of pheromone. These results suggest that octopamine may not be involved in regulation of pheromone production in H. zea. In abdomen incubation assays, synthetic Hez-PBAN stimulated pheromone production at doses as low as 10 fmol. Additionally, one female equivalent of hemolymph or serum from Scotophase females exhibited pheromonotropic activity that was comparable to activity elicited by 10 fmol synthetic Hez-PBAN. High pressure liquid Chromatographic (HPLC) fractionation of Scotophase H. zea hemolymph serum filtrates, obtained after filtration through molecular weight filters, suggested the presence of a pheromonotropic fraction with molecular weight that appears to be less than 3000.
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Studies on biogenic amines and their metabolites in nervous tissue and hemolymph of male cabbage looper moths - II. Photoperiod changes relative to random locomotor activity and pheromone-response thresholds
Comparative Biochemistry and Physiology Part C: Pharmacology Toxicology and Endocrinology, 1994Co-Authors: Charles E. Linn, M. G. Campbell, Kathy Poole, Wendell L. RoelofsAbstract:Levels of octopamine, 5-hydroxytryptamine, dopamine and their metabolites were measured in brain, corpora cardiaca/corpora allata complex, thoracic ganglia and optic lobes from individual male cabbage looper moths, Trichoplusia ni, using HPLC with electrochemical detection. Measurements were made from individuals in late photophase and compared with levels from individuals at mid-Scotophase. Individuals at mid-Scotophase had been observed for locomotor activity throughout the dark period and then assayed in the sustained-flight tunnel with a low, threshold, dose of sex pheromone prior to dissection. Individuals were selected for dissection if they exhibited a complete upwind flight to the pheromone source, or if they did not respond at all. Mid-Scotophase levels of octopamine in the brain and thoracic ganglia, dopamine in the thoracic ganglia, and 5-hydroxytryptamine in the brain and thoracic ganglia were all significantly lower than photophase levels. Scotophase levels of octopamine in individuals that responded to a low dose of pheromone were significantly lower than levels from males that did not respond. Levels of random locomotor activity over the Scotophase were not correlated with the probability of a male responding to the threshold dose of pheromone. There also was no correlation between brain mid-Scotophase levels of amines and the degree of locomotor activity exhibited, but there was a strong correlation between decreased levels of octopamine and dopamine in the thoracic ganglia and high levels of locomotor activity. Decreased levels of octopamine in the brain and thoracic ganglia over the dark period were correlated with increased levels of N-acetyloctopamine, suggesting that utilization of the amines occurs within the tissues over this time period. Mid-Scotophase levels of N-acetyldopamine were significantly greater than photophase levels, suggesting increased metabolism of this amine as well. Our results indicate that changes in amine levels within specific tissues can be correlated with behaviors exhibited by individual insects. The results support the hypothesis that octopamine, dopamine and 5-hydroxytryptamine exert modulatory or transmitter roles in the central nervous system of the cabbage looper moth.
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Control of pheromone biosynthesis in mated redbanded leafroller moths
Archives of Insect Biochemistry and Physiology, 1993Co-Authors: Russell A. Jurenka, Gemma Fabriás, Sonny B. Ramaswamy, Wendell L. RoelofsAbstract:Mating in the redbanded leafroller moth, Argyrotaenia velutinana, causes a permanent decline in pheromone titers. Three hours following the termination of mating, phermone titers were significantly decreased from premating levels, and titers remained low for at least four days after mating. Pheromone titers were similar in females that had been decapitated or mated for twenty-four hours. In the redbanded leafroller moth, two peptides control pheromone production. The pheromone biosynthesis activating neuropeptide is produced in the brain and the pheromonotropic bursa peptide is produced in the corpus bursae. Both peptides stimulated pheromone biosynthesis in mated females and extracts prepared from brains and bursae of mated females contained pheromonotropic activity. However, severing the ventral nerve cord before mating prevented the decline in pheromone titer that occurred in mated females. Hemolymph collected during Scotophase from mated females did not have pheromonotropic activity, whereas hemolymph collected during Scotophase from virgin females contained activity. These results indicate that mating produces a signal sent by the ventral nerve cord to the brain to stop the release of pheromone biosynthesis activating neuropeptide. © 1993 Wiley-Liss, Inc.
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Photoperiod cues and the modulatory action of octopamine and 5‐hydroxytryptamine on locomotor and pheromone response in male gypsy moths, Lymantria dispar
Archives of Insect Biochemistry and Physiology, 1992Co-Authors: Charles E. Linn, M. G. Campbell, Wendell L. RoelofsAbstract:Experiments were conducted to determine whether the biogenic amines octopamine (OA) and 5-hydroxytryptamine (5-HT) exert modulatory effects on pheromone responsiveness and random locomotor activity in male gypsy moths. When injected into males, OA significantly enhanced sensitivity to pheromone, while 5-HT enhanced general locomotor activity, results that were very similar to those previously shown for the cabbage looper. Maximal effect of the amines, however, was observed when injection occurred just prior to the onset of Scotophase, rather than photophase, as we had originally hypothesized for this diurnally active insect. Male gypsy moths also displayed a prominent Scotophase response, with sensitivity to pheromone greater in the scotphase compared with photophase, but with the level of random locomotor activity lower in Scotophase than in photophase. The upwind flight behavior of males to a pheromone source in a wind tunnel, as well as the time spent at the source, were also significantly different in the two light regimes. Furthermore, when exposed to a 1 h Scotophase (instead of the normal 8), or to continuous dark conditions, while males exhibited response to pheromone and locomotor activity during the same Scotophase and photophase periods as observed in a 16:8 light : dark cycle, the levels of response, as well as qualitative aspects of the upwind flight behaviors in both periods were a function of the light intensity. Our combined results suggest that male gypsy moths display a bimodal rhythm of locomotor and pheromone response over the diel cycle, with light intensity and Scotophase onset providing critical cues for the expression of behaviors, as well as the modulatory action of the amines. © 1992 Wiley-Liss, Inc.
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Role of photoperiod cues in regulating the modulatory action of octopamine on pheromone-response thresholds in the cabbage looper moth
Archives of Insect Biochemistry and Physiology, 1992Co-Authors: Charles E. Linn, Wendell L. RoelofsAbstract:Experiments were conducted to determine the relationship between photoperiod cues and the modulatory action of octopamine (OA) on male sensitivity to sex pheromone in the cabbage looper moth. Results showed that levels of random locomotor activity and response to pheromone, as well as the effectiveness of OA in enhancing male sensitivity, were dependent on the light intensity during the Scotophase period. The importance of Scotophase onset was further demonstrated by the fact that a 1 h period of dark (instead of the normal 8) was sufficient to elicit male response to pheromone, and the modulatory action of the amine, several hours later in photophase conditions during the “expected” mid-Scotophase period when peak response normally occurs. Furthermore, expression of the response rhythms and the effect of octopamine were maximal when injection of the amine and Scotophase onset occurred during a narrow temporal window around the expected time of Scotophase onset. Delays or advances in Scotophase onset or injection of octopamine resulted in decreased levels of behavior and loss of effectiveness of the amine. Studies involving a reversal in the photoperiod also support the idea that Scotophase onset is a critical time in the regulation of the general locomotor and pheromone-response rhythms exhibited by males. The combined results support a hypothesis that the modulatory action of octopamine is associated with physiological changes occurring at the onset of Scotophase, and that the periodicity of this action is influenced by an endogenous oscillator. © 1992 Wiley-Liss, Inc.
A. Huis - One of the best experts on this subject based on the ideXlab platform.
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Uscana lariophaga, West-African egg parasitoid of the cowpea bruchid beetle Callosobruchus maculatus photoperiod, parasitization and eclosion interactions.
Entomologia Experimentalis Et Applicata, 1995Co-Authors: A. Huis, S. O. AppiahAbstract:The diurnal pattern of parasitization and eclosion of the trichogrammatid Uscana lariophaga Steffan, egg parasitoid of the cowpea bruchid Callosobruchus maculatus (Fabricius) was studied for L12:D12 photoperiods. The wasp parasitized eggs throughout each 24-h period with about 70% of the parasitization taking place during the first 12 h regardless whether it was the photophase or the Scotophase. More female progeny was produced when the first 12-h period was photophase instead of Scotophase. Eclosion of wasps took place over a period of 4 days and occurred during the second half of the Scotophase and the first half of the photophase. The number of wasps eclosed during the photophase was similar to that eclosed during the Scotophase. Average development time was 8.9 days at 30° C. Male development was completed 6 to 8 h before the females, hence a higher percentage of females emerged in the later eclosion peaks. During Scotophases more females eclosed than during photophases. Although the results indicate that the wasp is able to perform under dark storage conditions the effect of permanent low light intensity remains to be studied.
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Uscana lariophaga, West-African egg parasitoid of the cowpea bruchid beetleCallosobruchus maculatus: photoperiod, parasitization and eclosion interactions
Entomologia Experimentalis et Applicata, 1995Co-Authors: A. Huis, S. O. AppiahAbstract:The diurnal pattern of parasitization and eclosion of the trichogrammatid Uscana lariophaga Steffan, egg parasitoid of the cowpea bruchid Callosobruchus maculatus (Fabricius) was studied for L12:D12 photoperiods. The wasp parasitized eggs throughout each 24-h period with about 70% of the parasitization taking place during the first 12 h regardless whether it was the photophase or the Scotophase. More female progeny was produced when the first 12-h period was photophase instead of Scotophase. Eclosion of wasps took place over a period of 4 days and occurred during the second half of the Scotophase and the first half of the photophase. The number of wasps eclosed during the photophase was similar to that eclosed during the Scotophase. Average development time was 8.9 days at 30°C. Male development was completed 6 to 8 h before the females, hence a higher percentage of females emerged in the later eclosion peaks. During Scotophases more females eclosed than during photophases. Although the results indicate that the wasp is able to perform under dark storage conditions the effect of permanent low light intensity remains to be studied.
N. A. Babilis - One of the best experts on this subject based on the ideXlab platform.
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Mating behaviour of the corn stalk borerSesamia nnonagrioides
Entomologia Experimentalis et Applicata, 1992Co-Authors: N. A. Babilis, B. E. MazomenosAbstract:The mating behaviour of the corn stalk borer Sesamia nonagrioides (Lef.) [Lepidoptera:Noctuidae] was studied under laboratory conditions at 25 ± 1 °C, 65 ± 5% r.h. and 16:8 (L:D) regime. The females began calling during the first Scotophase following emergence, the peak of calling occurred during the second Scotophase and thereafter decreased. Maximum calling was observed between the fourth and sixth hour of the Scotophase. The calling pattern varied with age. During the first and second Scotophase most of the females were calling continuously, while during the third and fourth Scotophase periodic calling was observed. The mean onset of calling was advanced and the mean length of calling per day was increased slightly as the female became older. Females held for 72 h in continuous darkness exhibited an endogenous circadian rhythm of calling. Matings began during the first Scotophase following emergence and the peak of mating was observed during the second Scotophase. Mated females did not remate. Few males mated more than once during the following Scotophases.
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Pheromone production in Sesamia nonagrioides: Diel periodicity and effect of age and mating
Journal of Insect Physiology, 1992Co-Authors: N. A. Babilis, B. E. MazomenosAbstract:Abstract Diel periodicity of pheromone production and the effect of age and mating on the pheromone titre of the female Sesamia nonagrioides (Lef.) was studied. The pheromone titre was measured by quantitative capillary gas chromatographic analysis. Females began producing pheromone 20–24 h following emergence. The higher quantity of pheromone was measured during the second Scotophase. The pheromone gland contained detectable quantities 2 h after the onset of the Scotophase and reached maximal levels during the sixth hour in the second Scotophase. The pheromone titre was very low 2 h after the onset of the photoperiod. Females began calling 4 h after the onset of the Scotophase and peak calling activity was observed at the sixth hour. Mating suppressed pheromone biosynthesis. The quantity of pheromone measured in mated females 24, 48 and 72 h after mating was significantly lower than that of virgin females of similar age.
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Mating behaviour of the corn stalk borer Sesamia nonagrioides.
Entomologia Experimentalis Et Applicata, 1992Co-Authors: N. A. Babilis, B. E. MazomenosAbstract:The mating behaviour of the corn stalk borer Sesamia nonagrioides (Lef.) [Lepidoptera: Noctuidae] was studied under laboratory conditions at 25 ± 1 ° C, 65 ± 5 % r.h. and 16:8 (L:D) regime. The females began calling during the first Scotophase following emergence, the peak of calling occurred during the second Scotophase and thereafter decreased. Maximum calling was observed between the fourth and sixth hour of the Scotophase. The calling pattern varied with age. During the first and second Scotophase most of the females were calling continuously, while during the third and fourth Scotophase periodic calling was observed. The mean onset of calling was advanced and the mean length of calling per day was increased slightly as the female became older. Females held for 72 h in continuous darkness exhibited an endogenous circadian rhythm of calling. Matings began during the first Scotophase following emergence and the peak of mating was observed during the second Scotophase. Mated females did not remate. Few males mated more than once during the following Scotophases.
