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Mated Females (mated + female)
Selected AbstractsCalling behaviour of adult female Helicoverpa armigera (Hübner) (Lep., Noctuidae) of overwintering generation and effects of matingJOURNAL OF APPLIED ENTOMOLOGY, Issue 2 2000M. L. Hou The calling behaviour of overwintering generation females of Helicoverpa armigera and the effects of mating were studied in the laboratory at 24 ± 1°C and under reversed light-dark cycle (16 h light : 8 h dark). Age had a significant influence on calling patterns. Based on calling age, mean number of calling bouts and total calling length of virgin females increased significantly, and mean onset time of calling advanced significantly from calling day 1 to subsequent calling days. Females of the overwintering generation exhibited more short bouts in calling, and some females that initiated calling on a previous day did not call on subsequent days. Mating had no effect on the overall patterns, but did affect calling behaviour. Mated females did not resume calling after mating during the same scotophase and, on the day following mating, mated females called less frequently and for a shorter duration, but thereafter increased to the same level of virgin females of the same calling age. Furthermore, as the moth aged, the percentage of mated females calling was lower than that of virgin females. [source] Foraging and mate-finding in the silver Y moth, Autographa gamma (Lepidoptera: Noctuidae) under the risk of predationOIKOS, Issue 2 2003Niels Skals Animal foraging and reproductive behaviour is influenced by other simultaneous demands such as predator avoidance. The trade-offs between these demands may depend on sex or mating experience. This study demonstrates that the olfactory-mediated foraging and mate-seeking behaviours in the silver Y moths, Autographa gamma, are affected by auditory cues mimicking their bat predators. Both males and females changed their foraging behaviour under simulated predation risk. Fewer moths reached the odour source following sound stimulation and the time to find the odour source increased by up to 250%. However, there were no significant differences between male and female ability to reach the plant odour source or the duration of the flight towards the source when stimulated with ultrasound. Hence females are not more cautious than males when observed in the same behavioural context. Risk-taking in males was independent of whether they were flying toward a flower odour or sex pheromones having equal attractive value. This indicates that the trade-off between olfactory and acoustic cues is independent the type of odour. Mated females were not as strongly affected by sound as non-mated, indicating that flower odours have a higher adaptive value for mated females, suggesting that some processes following mating experience influence the trade-off between flower odours and simulated bat sounds. [source] Behavioral evidence for a female-produced sex attractant in Diaphorina citriENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 3 2008Erik J. Wenninger Abstract Diaphorina citri Kuwayama (Hemiptera: Psyllidae) is an important worldwide pest of citrus. It vectors three phloem-restricted bacteria in the genus Candidatus Liberibacter that cause huanglongbing (citrus greening disease). Studies were conducted to examine the behavioral responses of male and female D. citri to conspecifics of the same and opposite sex, with and without associated citrus host plants, in both open-air arena choice assays and Y-tube olfactometer assays. Virgin and mated male D. citri colonized citrus plants that were currently or had been previously colonized by virgin or mated female D. citri in greater numbers than control plants without females. However, males or females did not accumulate more on plants colonized by conspecifics of the same sex compared to uninfested plants, and females showed no preference for plants pre-infested with males compared with uninfested controls. In complementary Y-tube olfactometer assays, virgin and mated males chose arms with odor sources from mated females compared with blank controls in the absence of associated citrus host plant volatiles. In both behavioral assays, mated female D. citri appeared more attractive than virgin females. The vibrational calling behavior of male D. citri was reduced when males were challenged by the odors of conspecific mated females relative to when males were challenged by the odor of other males. Collectively, our results provide behavioral evidence for a female-produced volatile sex attractant pheromone in D. citri. Future identification and synthesis of a sex attractant pheromone will be an important contribution to current monitoring and management practices for D. citri. [source] Biology of Bactrocera (Zeugodacus) tau (Walker) (Diptera: Tephritidae)ENTOMOLOGICAL RESEARCH, Issue 5 2010Shakti Kumar SINGH Abstract The biology of the fruit fly Bactrocera tau, an important horticultural pest, was studied under laboratory conditions at 25°C and 60,70% relative humidity on Cucurbita maxima. The duration of mating averaged 408.03 ± 235.93 min. After mating, the female fly had a preoviposition period of 11.7 ± 4.49 days. The oviposition rate was 9.9 ± 8.50 eggs and fecundity was 464.6 ± 67.98 eggs/female. Eggs were elliptical, smooth and shiny white, turning darker as hatching approached, and measured 1.30 ± 0.07 mm × 0.24 ± 0.04 mm. The chorion has polygonal microsculpturing and is species-specific with polygonal walls. The egg period lasts for 1.3 ± 0.41 days. The duration of the larval period is 1.2 ± 0.42, 1.7 ± 0.48 and 4.0 ± 0.94 days for first, second and third instars, respectively. Pupation occurs in the sand or soil and pupal periods are 7.0 ± 0.47 days. The life cycle from egg to adult was completed in 14.2 ± 1.69 days; the longevity of mated females and males was 130.33 ± 14.18 and 104.66 ± 31.21 days, respectively. At least two to three generations were observed from June 2008 to June 2009. [source] Calling behaviour of adult female Helicoverpa armigera (Hübner) (Lep., Noctuidae) of overwintering generation and effects of matingJOURNAL OF APPLIED ENTOMOLOGY, Issue 2 2000M. L. Hou The calling behaviour of overwintering generation females of Helicoverpa armigera and the effects of mating were studied in the laboratory at 24 ± 1°C and under reversed light-dark cycle (16 h light : 8 h dark). Age had a significant influence on calling patterns. Based on calling age, mean number of calling bouts and total calling length of virgin females increased significantly, and mean onset time of calling advanced significantly from calling day 1 to subsequent calling days. Females of the overwintering generation exhibited more short bouts in calling, and some females that initiated calling on a previous day did not call on subsequent days. Mating had no effect on the overall patterns, but did affect calling behaviour. Mated females did not resume calling after mating during the same scotophase and, on the day following mating, mated females called less frequently and for a shorter duration, but thereafter increased to the same level of virgin females of the same calling age. Furthermore, as the moth aged, the percentage of mated females calling was lower than that of virgin females. [source] Mating of Xenos vesparum (Rossi) (Strepsiptera, Insecta) revisitedJOURNAL OF MORPHOLOGY, Issue 3 2005L. Beani Abstract The controversial mating of the strepsipteran Xenos vesparum was studied to investigate the possible sperm routes for fertilization. The female, which is a neotenic permanent endoparasite of Polistes wasps, extrudes only its anterior region, the "cephalothorax," from the host abdomen. This region has an opening where both mating and larval escape occur. Observations with scanning and transmission electron microscopy revealed spermatozoa not only in the hemocoel, but also in the "ventral canal" (an extragenital duct peculiar to strepsipteran females) and in the "genital ducts" (ectodermal invaginations connecting the ventral canal to the hemocoel) of recently mated females. Xenos vesparum spermatozoa can reach the oocytes either through the hemocoel as a result of a hypodermic insemination, or by moving along the extragenital ducts, which are later used by first instar larvae to escape. The hypothesis of hypodermic insemination is reconsidered in the light of behavioral and ultrastructural evidence. J. Morphol. © 2005 Wiley-Liss, Inc. [source] Foraging and mate-finding in the silver Y moth, Autographa gamma (Lepidoptera: Noctuidae) under the risk of predationOIKOS, Issue 2 2003Niels Skals Animal foraging and reproductive behaviour is influenced by other simultaneous demands such as predator avoidance. The trade-offs between these demands may depend on sex or mating experience. This study demonstrates that the olfactory-mediated foraging and mate-seeking behaviours in the silver Y moths, Autographa gamma, are affected by auditory cues mimicking their bat predators. Both males and females changed their foraging behaviour under simulated predation risk. Fewer moths reached the odour source following sound stimulation and the time to find the odour source increased by up to 250%. However, there were no significant differences between male and female ability to reach the plant odour source or the duration of the flight towards the source when stimulated with ultrasound. Hence females are not more cautious than males when observed in the same behavioural context. Risk-taking in males was independent of whether they were flying toward a flower odour or sex pheromones having equal attractive value. This indicates that the trade-off between olfactory and acoustic cues is independent the type of odour. Mated females were not as strongly affected by sound as non-mated, indicating that flower odours have a higher adaptive value for mated females, suggesting that some processes following mating experience influence the trade-off between flower odours and simulated bat sounds. [source] Female mating success and risk of pre-reproductive death in a protandrous grasshopperOIKOS, Issue 2 2002Raúl Cueva Del Castillo Numerous studies have assessed the adaptive value of protandry for males in several insect species, considering that male emergence is determined by female availability. However, the possible advantage of the time of emergence for females on their mating success in protandrous insect species has only been explored theoretically. By studying the grasshopper Sphenarium purpurascens we evaluated the hypothesis that late emergence could be adaptive for females. If female maturation occurs when the population density is higher and the sex ratio (males/females) is biased to males, their probability of mating increases. Thus, in this study we estimated (1) the opportunity for mating in females as a function of their sexual maturation time, population density, and sex ratio at the moment they reached sexual maturity. In addition, (2) an analysis incorporating female body size and the total number of female matings was performed. Both analyses support the occurrence of protandry in the studied population. Under the first approach, females with intermediate maturation time had a higher probability of being mated than earlier and late matured females. Thus, it suggests that stabilising selection is acting on female maturation time and this may affect selection on male maturation time. Furthermore, the proportion of mated females increased when the sex ratio was biased to males, and stabilising selection on maturation time was detected also. However, the number of matings of a female depended on her body size. Females with larger body size had more matings than smaller ones at the beginning of the reproductive season. Because selection acts differently on maturation time in males and females of S. purpurascens this result is consistent with a condition for the maintenance of protandry in the population. The present results are discussed in the light of the models for the evolution of protandry. [source] Juvenile hormone III produced in male accessory glands of the longhorned beetle, Apriona germari, is transferred to female ovaries during copulationARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY (ELECTRONIC), Issue 1 2010Ling Tian Abstract We report on juvenile hormone (JH) biosynthesis in vitro by male accessory glands (MAGs) in the longhorned beetle, Aprionona germari, accompanied by the transfer of JH from males to females during copulation. JH was extracted from the MAGs and separated by reversed-phase high-performance liquid chromatography. JH III was identified as the major JH by gas chromatography,mass spectrometry. A radiochemical assay and a non-radioactive method were used to measure the in vitro rate of JH biosynthesis by the MAGs. After 4,h of incubation with 3H-methionine in the medium, the radioactivity in the MAGs substantially increased. In a separate assay, incubation of the MAGs with non-radioactive methionine for 4,h resulted in a 39% increase in JH III. Seven-day-old males were injected with medium 199 containing 3H,methionine and 24,h later they were mated with virgin females. Hemolymph and the MAGs were collected from the mated males and hemolymph, ovaries and eggs were collected from the mated females for assaying radioactive JH. The radioactivity incorporated into JH in the MAGs was transferred to the females during copulation and later transferred into their eggs. Assayed 1,h after copulation, JH III level in the MAGs decreased 42% and the content of JH III in the male hemolymph did not change, whereas the content of JH III in the female hemolymph and ovaries both increased. © 2010 Wiley Periodicals, Inc. [source] Gonadoinhibitory effects of Neb-colloostatin and Neb-TMOF on ovarian development in the mealworm, Tenebrio molitor L.ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY (ELECTRONIC), Issue 3 2007O. Wasielewski Abstract The gonadostatic action of the peptides Neb-colloostatin (SIVPLGLPVPIGPIVVGPR) and Neb-TMOF (NPTNLH) from Neobellieria bullata was studied in female mealworm Tenebrio molitor. Both peptides potently inhibit ovarian development and terminal oocyte maturation of mated females during their first reproductive cycle. Injection of 4 ,g of Neb-colloostatin or Neb-TMOFNeb-TMOF reduced, at day 4 of the cycle, the size of the terminal oocytes to about half or one third of the normal size in saline-injected controls. In addition, follicular patency was arrested. The injections of Neb-colloostatin and Neb-TMOF also caused a delay to the first ovulation and oviposition as well as a reduction of the number of eggs by about 50% in the first 3 days of the oviposition period. At 4 days after adult emergence, none of the peptides had caused significant changes in protein concentration or composition of the haemolymph. However, both peptides reduced total protein content in ovaries and induced qualitative changes in ovarian protein patterns. Electrophoretic analyses indicated that Neb-colloostatin and Neb-TMOF caused a loss of two proteins (150, 180 kDa) and a drastic reduction of 4 others (39, 43, 47, 130 kDa), which are the most abundant ones in ovaries of control females. On the other hand, they increased the concentration of 2 other polypeptides (65, 70 kDa), which normally occur in insignificant quantities in ovaries. Our results indicate that both peptides have a very similar mode of action despite the differences in their amino acid sequence. They seem to interfere with vitellogenin production by the fat body as well as with vitellogen uptake by the oocytes through modification of patency. Arch. Insect Biochem. Physiol. 64:131,141, 2007. © 2007 Wiley-Liss, Inc. [source] The piercing-sucking herbivores Lygus hesperus and Nezara viridula induce volatile emissions in plants ,,ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY (ELECTRONIC), Issue 2 2005Livy Williams III Abstract Plant volatiles induced by herbivory are often used as olfactory cues by foraging herbivores and their natural enemies, and thus have potential for control of agricultural pests. Compared to chewing insects and mites, little is known about plant volatile production following herbivory by insects with piercing-sucking mouthparts. Here, we studied factors (insect life stage, gender, the role of salivary glands, and type of bioassay used for volatile induction) that influence the induction of plant volatiles by two agriculturally important hemipterans, Lygus hesperus and Nezara viridula. Feeding on intact cotton by virgin females of L. hesperus induced 2.6-fold greater volatile response compared to that induced by mated females, possibly due to increased feeding activity by virgin females. This plant volatile response was associated with elicitors present in the insect's salivary glands as well as to the degree of mechanical injury. Feeding injury by N. viridula females also increased volatile emissions in intact maize by approximately 2-fold compared to control plants. Maize seedlings injured by N. viridula emitted higher amounts of the monoterpene linalool, the sesquiterpenes (E)-,-caryophyllene, ,- trans -bergamotene, and (E,E)-,-farnesene, and the homoterpene (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene, but not amounts of green leaf volatiles, compared to uninjured plants. Emissions from intact maize injured by adult males were lower than those emitted by adult females of the same age and did not differ from those emitted by uninjured plants. Similarly, feeding by virgin female N. viridula followed by excision led to 64% higher quantities of volatiles compared to untreated plants. Volatile emission in excised plants, however, was considerably greater than in intact plants, suggesting that careful consideration must be given to bioassay design in studies of herbivore-induced plant volatiles. Salivary gland extracts of N. viridula led to sesquiterpene emissions approximately 2.5-fold higher than for controls, although no significant differences were observed for green leaf volatiles, monoterpenes, and homoterpenes. These results indicate that L. hesperus and female N. viridula feeding induce volatile production in plants, and that volatile production is affected by gender and life stage of the bug. Although oviposition and mechanical injury by stylets may increase release of volatiles, elicitors from salivary glands of L. hesperus and N. viridula also seem to play a role in the emission of plant volatiles. Arch. Insect Biochem. Physiol. 58:84,96, 2005. Published 2005 Wiley-Liss, Inc. [source] Limited male dispersal in a social spider with extreme inbreedingBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 2 2009YAEL LUBIN Cooperatively breeding animals commonly avoid incestuous mating through pre-mating dispersal. However, a few group-living organisms, including the social spiders, have low pre-mating dispersal, intra-colony mating, and inbreeding. This results in limited gene flow among colonies and sub-structured populations. The social spiders also exhibit female-biased sex ratios because survival benefits to large colonies favour high group productivity, which selects against 1 : 1 sex ratios. Although propagule dispersal of mated females may occasionally bring about limited gene flow, little is known about the role of male dispersal. We assessed the extent of male movement between colonies in natural populations both experimentally and by studying colony sex ratios over the mating season. We show that males frequently move to neighbouring colonies, whereas only 4% of incipient nests were visited by dispersing males. Neighbouring colonies are genetically similar and movement within colony clusters does not contribute to gene flow. Post-mating sex ratio bias was high early in the mating season due to protandry, and also in colonies at the end of the season, suggesting that males remain in the colony when mated females have dispersed. Thus, male dispersal is unlikely to facilitate gene flow between different matrilineages. This is consistent with models of non-Fisherian group-level selection for the maintenance of female biased sex ratios, which predict the elimination of male dispersal. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society 2009, 97, 227,234. [source] Chastity belts in gartersnakes: the functional significance of mating plugsBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 3 2000R. SHINE Male red-sided gartersnakes (Tfiamnophis sirtalis parietalis) deposit a thick gelatinous plug that occludes the female cloaca after copulation. Previous workers have interpreted the plug as a sexually-selected adaptation to (1) physically prevent re-mating by the female, and/or (2) provide pheromonal cues to discourage courtship by rival males or to decrease receptivity by females. Our data support the former hypothesis, but not the latter. Plugs serve as effective physical barriers to additional copulation for <72 h, but this is long enough for most females to become unreceptive, and/or disperse from the mating aggregation. Experimental removal of plugs immediately after copulation results in some re-mating by females, but plug removal several hours later does not rekindle sexual receptivity. Contrary to previous work, our experiments show that fluids associated with copulation (rather than the plug per se) are responsible for the rapid decline of male interest in mated females. Thus, the plug's primary function is to physically prevent matings rather than as a source of pheromonal cues to manipulate the behaviour of females or rival males. Plug mass is determined not only by a male's body size, but by his prior mating history (plug mass decreases with repeated mating) and by the size of his partner (males allocate larger plugs to larger females). Gartersnakes are unusual not only in their production of mating plugs, but also in their brief duration of copulation compared to other snakes. Mating plugs may have evolved in gartersnakes to reduce mating times, because of the extremely high ,opportunity cost' of prolonged mating to a male gartersnake in a mating aggregation. [source] | ||||||||||