-
PloS One Aug 2008Synthetic mosquito oviposition attractants are sorely needed for surveillance and control programs for Culex species, which are major vectors of pathogens causing...
Synthetic mosquito oviposition attractants are sorely needed for surveillance and control programs for Culex species, which are major vectors of pathogens causing various human diseases, including filariasis, encephalitis, and West Nile encephalomyelitis. We employed novel and conventional chemical ecology approaches to identify potential attractants, which were demonstrated in field tests to be effective for monitoring populations of Cx. p. quinquefasciatus in human dwellings. Immunohistochemistry studies showed that an odorant-binding protein from this species, CquiOBP1, is expressed in trichoid sensilla on the antennae, including short, sharp-tipped trichoid sensilla type, which house an olfactory receptor neuron sensitive to a previously identified mosquito oviposition pheromone (MOP), 6-acetoxy-5-hexadecanolide. CquiOBP1 exists in monomeric and dimeric forms. Monomeric CquiOBP1 bound MOP in a pH-dependent manner, with a change in secondary structure apparently related to the loss of binding at low pH. The pheromone antipode showed higher affinity than the natural stereoisomer. By using both CquiOBP1 as a molecular target in binding assays and gas chromatography-electroantennographic detection (GC-EAD), we identified nonanal, trimethylamine (TMA), and skatole as test compounds. Extensive field evaluations in Recife, Brazil, a region with high populations of Cx. p. quinquefasciatus, showed that a combination of TMA (0.9 microg/l) and nonanal (0.15 ng/microl) is equivalent in attraction to the currently used infusion-based lure, and superior in that the offensive smell of infusions was eliminated in the newly developed synthetic mixture.
Topics: Animals; Chemotactic Factors; Culex; Ecology; Female; Housing; Humans; Kinetics; Oviposition; Population Dynamics; Receptors, Odorant
PubMed: 18725946
DOI: 10.1371/journal.pone.0003045 -
Scientific Reports Aug 2021The absolute dominant species that infests wild population of Przewalski's horse (Equus przewalskii) is Gasterophilus pecorum, and feces of released Przewalski's horse,...
The absolute dominant species that infests wild population of Przewalski's horse (Equus przewalskii) is Gasterophilus pecorum, and feces of released Przewalski's horse, a habitat odor, plays an important role in mating and ovipositing locations of G. pecorum. To screen out unique volatiles for attracting G. pecorum, volatiles from fresh feces of released horses at stages of pre-oviposition (PREO), oviposition (OVIP), and post-oviposition (POSO) of G. pecorum, and feces with three different freshness states (i.e., Fresh, Semi-fresh, and Dry) at OVIP were collected by dynamic headspace adsorption and determined by automatic thermal desorption GC-MS. Results show that there were significant differences in fecal volatiles within both test conditions. Of the five most abundant volatiles from the five individual samples, the most important volatile was ammonium acetate at OVIP/Fresh, followed by acetophenone (Semi-fresh), toluene (PREO, OVIP and POSO), butanoic acid (OVIP and Semi-fresh), acetic acid (PREO, POSO and Semi-fresh), 1,6-octadiene,3,7-dimethyl-,(S)- (PREO, OVIP and POSO), 1,5,9-undecatriene,2,6,10-trimethyl-,(Z)- (PREO and Semi-fresh) and caprolactam (all conditions), which seem to be critical substances in oviposition process of G. pecorum. The findings may be beneficial to development of G. pecorum attractants, facilitating prevention and control of infection by G. pecorum to released Przewalski's horse.
Topics: Animals; Diptera; Ecosystem; Feces; Horses; Larva; Oviposition
PubMed: 34341455
DOI: 10.1038/s41598-021-95162-9 -
PloS One 2018Bactrocera cucurbitae (Coquillett) is an important pest of cucurbit crops and certain vegetables in Asia, the Middle East, Africa and Hawaii. Most studies on B....
BACKGROUND
Bactrocera cucurbitae (Coquillett) is an important pest of cucurbit crops and certain vegetables in Asia, the Middle East, Africa and Hawaii. Most studies on B. cucurbitae have focussed on the effects of prolonged high temperature and very few have examined the effects of short-term exposures to high-temperature on behaviour.
RESULTS
In this study, short-term of high-temperature treatments of 33°C, 37°C, 41°C and 45°C were maintained for 1-3hr, and long-term, variable high-temperature treatments were established that consisted of experienced one, two and three times high temperatures stages to 31°C, 33°C, 34°C, 35°C, 36°C, 37°C, 41°C and 45°C for 7hr. We compared the effects of the different high temperatures regimes changes treatments on the mating, oviposition and thermotactic taxis of the flies. The results showed that exposure to a 45°C/1hr treatment, delayed both initiation of mating and oviposition for 8 hr relative to the control but mating and was observed 41 times and oviposition 47 times. By comparison, in the control, mating commenced immediately and was observed 38.3 times and oviposition was observed 41.3 times. Under the other treatments, all the indices for the flies declined with the increase in temperature and duration of exposure.
CONCLUSION
Results showed that 1hr of exposure to 45°C significantly stimulated mating, oviposition and thermotactic behaviour of the flies. These results could improve our understanding of the mechanisms responsible for the population dynamics of B. cucurbitae during the high-temperature season.
Topics: Animals; Female; Hot Temperature; Male; Oviposition; Sexual Behavior, Animal; Taxis Response; Tephritidae
PubMed: 30235275
DOI: 10.1371/journal.pone.0204065 -
Journal of Medical Entomology Feb 2018A growing body of literature on mosquito oviposition behavior supports the hypothesis that females place eggs in habitats that provide best available opportunity for...
A growing body of literature on mosquito oviposition behavior supports the hypothesis that females place eggs in habitats that provide best available opportunity for growth, development, and maturation of their offspring. We conducted a field experiment to evaluate Culex oviposition behavior in response to the interspecific competitor Aedes triseriatus (Say) (Diptera: Culicidae) larvae, and resources in the form of quantity of plant detritus, and dissolved nitrogen (TN) and phosphorus (TP) derived from that detritus. We tested a set of specific predictions: 1) As a poorer competitor, Culex will avoid ovipositing in containers with superior interspecific competitors; 2) Culex choose oviposition habitats that contain greater amount of resources for the microbial food of their offspring; 3) Sufficiently high resource abundance can override avoidance of oviposition in containers with interspecific competitors. Culex restuans Theobald (Diptera: Culicidae) was the only species ovipositing, and the oviposition responses changed over time. The effect of resources was more important in driving oviposition decisions at the beginning and end of the experiment. The amount of resources, as manifest by TN and TP concentrations, had differential effects on oviposition. At the beginning females laid more eggs in containers with low detritus, which had the highest TN. After that, females preferred those containers with high detritus, which had low TN and high TP. The effect of competitors was important only during the middle of the experiment. Paradoxically, even as a poorer competitor Cx. restuans preferentially oviposited in containers with late-instar Ae. triseriatus, suggesting that the presence of successful heterospecifics indicates a good quality larval habitat.
Topics: Aedes; Animals; Culex; Ecosystem; Female; Larva; Oviposition
PubMed: 29194537
DOI: 10.1093/jme/tjx218 -
Journal of Insect Science (Online) 2012The western tarnished plant bug, Lygus hesperus Knight (Hemiptera: Miridae) is a key pest of fruit, vegetable, and field crops in the western United States, but many...
The western tarnished plant bug, Lygus hesperus Knight (Hemiptera: Miridae) is a key pest of fruit, vegetable, and field crops in the western United States, but many aspects of L. hesperus ecology are poorly documented. A sound understanding of oviposition behavior and characterization of the phases of embryonic development would be useful in studies of interactions between L. hesperus and its hosts, and in efforts to better understand the developmental consequences of low temperatures. Because L. hesperus insert their eggs into the host, most of the egg is obscured from view, and some aspects of oviposition and subsequent egg development cannot be observed directly. A novel observational method which took advantage of the propensity for L. hesperus to oviposit in semi-transparent sheets of agarose was used to observe oviposition and subsequent embryonic development. Lygus hesperus females stylet-probed prospective oviposition sites and during oviposition the ovipositor followed the path of the final probe. Oviposition, from insertion to withdrawal of the ovipositor, required ∼30 seconds. Identifiable phases of embryo development included egg swelling, katatrepsis, appearance of body segments and appendages, development of red pigmentation in the eyes and terminal antennal segments, and formation of the 3(rd) embryonic cuticle. These phases were observed at about 0.3, 0.4, 0.5, 0.6, and 0.8 of the total duration between oviposition and hatch, respectively. Infertile eggs did not exhibit any of these phases. Our descriptions of embryonic development will facilitate the study of L. hesperus egg biology and ecology, and permit estimates of egg population age structure and prediction of egg hatch.
Topics: Animals; Female; Heteroptera; Oviposition; Ovum; Sepharose
PubMed: 22943440
DOI: 10.1673/031.012.3601 -
Journal of the Royal Society, Interface Mar 2022The female locust has a unique mechanism for digging in order to deposit its eggs deep in the ground. It uses two pairs of sclerotized valves to displace the granular...
The female locust has a unique mechanism for digging in order to deposit its eggs deep in the ground. It uses two pairs of sclerotized valves to displace the granular matter, while extending its abdomen as it propagates underground. This ensures optimal conditions for the eggs to incubate and provides them with protection from predators. Here, the direction-dependent biomechanics of the locust's major, dorsal digging valves are quantified and analysed under forces in the physiological range and beyond, considering the hydration level as well as the females' sexual maturation state. Our findings reveal that the responses of the valves to compression forces in the digging and propagation directions change upon sexual maturation to follow their function and depend on environmental conditions. In addition, mature females, which lay eggs, have stiffer valves, up to approximately 19 times the stiffness of the pre-mature locusts. The valves are stiffer in the major working direction, corresponding to soil shuffling and compression, compared with the direction of propagation. Hydration of the valves reduces their stiffness but increases their resilience against failure. These findings provide mechanical and materials guidelines for the design of novel non-drilling burrowing tools, including three-dimensionally printed anisotropic materials based on composites.
Topics: Animals; Biomechanical Phenomena; Biophysics; Female; Grasshoppers; Oviposition
PubMed: 35291831
DOI: 10.1098/rsif.2021.0955 -
Scientific Reports Nov 2016Mosquito oviposition site selection is essential for vector population dynamics and malaria epidemiology. Irrigated rice cultivations provide ideal larval habitats for...
Mosquito oviposition site selection is essential for vector population dynamics and malaria epidemiology. Irrigated rice cultivations provide ideal larval habitats for malaria mosquitoes, which has resulted in increased prevalence of the malaria vector, Anopheles arabiensis, in sub-Saharan Africa. The nature and origin of the cues regulating this behaviour are only now being elucidated. We show that gravid Anopheles arabiensis are attracted and oviposit in response to the odour present in the air surrounding rice. Furthermore, we identify a synthetic rice odour blend, using electrophysiological and chemical analyses, which elicits attraction and oviposition in laboratory assays, as well as attraction of free-flying gravid mosquitoes under semi-field conditions. This research highlights the intimate link between malaria vectors and agriculture. The identified volatile cues provide important substrates for the development of novel and cost-effective control measures that target female malaria mosquitoes, irrespective of indoor or outdoor feeding and resting patterns.
Topics: Animals; Anopheles; Female; Malaria; Mosquito Vectors; Oryza; Oviposition; Volatile Organic Compounds
PubMed: 27901056
DOI: 10.1038/srep37930 -
Parasites & Vectors Jun 2023Shanghai has numerous high-rise apartment and office buildings, but the effects of these high-rise spaces on the vertical dispersal, oviposition and blood feeding...
BACKGROUND
Shanghai has numerous high-rise apartment and office buildings, but the effects of these high-rise spaces on the vertical dispersal, oviposition and blood feeding behavior of Aedes albopictus are unknown.
METHODS
In six multi-story building blocks in downtown Shanghai, 174 mosq-ovitraps (MOT) were placed both indoors and outdoors for Ae. albopictus collection at different vertical heights from the 1st to 6th floors and a terrace on the 8th floor. Collections were made for 4 months. The human landing catch (HLC) method for Ae. albopictus monitoring was also conducted on 6 consecutive days on six floors of two of the six buildings to study the feeding behavior of Ae. albopictus at different heights.
RESULTS
Both MOTs and HLCs collected Ae. albopictus at all monitored heights. The vertical distribution, oviposition pattern and biting behavior varied significantly among the seven heights (1st-6th floors and 8th floor) (mosq-ovitrap index (MOI): X = 140.616, df = 6, P < 0.001; HLC: F = 15.111, P < 0.001). The MOI at low heights (1st + 2nd floors) was significantly higher than that at medium (3rd + 4th floor, P < 0.001) and high heights (5th + 6th floors, P < 0.001), and there was no significant difference in the MOI for the 3rd-6th floors. The outdoor MOIs were significantly higher than indoor MOIs at all heights (outdoor 23.09% vs. indoor 9.58%, X = 74.121, df = 1, P < 0.001). Aedes albopictus HLC density on the ground floor was significantly higher than that on all other heights (5.04 vs. 0.13, 0.29, 0.58, 0.79 and 1.50 per half hour, P < 0.05), while no difference was detected among the heights above the ground floor (P > 0.05).
CONCLUSIONS
Aedes albopictus is more common near the ground level, but it can easily disperse to higher floors in the multi-story buildings of urban Shanghai. No significant differences in Ae. albopictus density were detected within the 3rd-6th floors using MOT or HLC. This suggests that Ae. albopictus might also disperse to areas above the 6th floor and seek hosts there. Aedes albopictus prefers to oviposit outdoors; however, Ae. albopictus was also able to inhabit, oviposit and engage in blood-feeding behavior indoors on different floors. The three-dimensional dispersal pattern of Ae. albopictus in urban areas could facilitate arbovirus transmission and increase the difficulty of dengue control.
Topics: Animals; Female; Humans; Aedes; China; Feeding Behavior; Oviposition; Dengue
PubMed: 37264465
DOI: 10.1186/s13071-023-05732-1 -
Journal of Insect Science (Online) 2015Tirumala limniace Cramer as an ornamental butterfly is utilized in butterfly garden, in this article we study their adult activities include flight, foraging, courtship,...
Tirumala limniace Cramer as an ornamental butterfly is utilized in butterfly garden, in this article we study their adult activities include flight, foraging, courtship, mating, and oviposition. We found that males spent 22.1% of its time flying, 14.1% foraging, 63.8% in courtship and mating. And females spent 30.8% of its time flying, 10.1% foraging, 57.1% in courtship and mating, and 2% ovipositing. Adults emerged from pupae when temperatures were above 23.5°C and eclosion took only ∼1 min, typically followed by a small amount of flight on the first day. Flight activity peaked from the ninth to the thirteenth day after eclosion, and there were two daily peak flight times: 10:00-13:00 and 15:00-18:00. The peak of flower-visiting activity was from the eighth to the thirteenth day after eclosion, and there were two daily peak foraging times: 11:00-12:00 and 16:00-17:00. Flight and foraging frequency and time were positively correlated and both were closely related to temperature, with very little flight or foraging below 18°C and an increase at temperatures above 22°C. Courtship and mating took place on the sixth day after eclosion, while oviposition occurred the following day. Oviposition occurred over 8 d, and the shortest time of a single oviposition was 2 s. The average life expectancy of males was 16.5 d, while that of females was 15 d.
Topics: Animals; Appetitive Behavior; Butterflies; Circadian Rhythm; Courtship; Female; Flight, Animal; Flowers; Male; Oviposition; Sexual Behavior, Animal; Temperature
PubMed: 26106088
DOI: 10.1093/jisesa/iev061 -
International Journal of Molecular... Dec 2018Plant resistance traits against insect herbivores are extremely plastic. Plants respond not only to the herbivory itself, but also to oviposition by herbivorous insects....
Plant resistance traits against insect herbivores are extremely plastic. Plants respond not only to the herbivory itself, but also to oviposition by herbivorous insects. How prior oviposition affects plant responses to larval herbivory is largely unknown. Combining bioassays and defense protein activity assays with microarray analyses and metabolite profiling, we investigated the impact of preceding oviposition on the interaction of with the generalist lepidopteran herbivore at the levels of the plant's resistance, transcriptome and metabolome. We found that oviposition increased plant resistance to the subsequent feeding larvae. While constitutive and feeding-induced levels of defensive protease inhibitor activity remained unaffected, pre-exposure to eggs altered 's transcriptional and metabolic response to larval feeding in leaves local and systemic to oviposition. In particular, genes involved in phenylpropanoid metabolism were more strongly expressed in previously oviposited plants, which was reflected by reciprocal changes of primary metabolites upstream and within these pathways. Our data highlight that plants integrate signals from non-threatening life stages of their natural enemies to optimize their response when they become actually attacked. The observed transcriptional and metabolic reshaping of 's response to herbivory suggests a role of phenylpropanoids in oviposition-primed plant resistance.
Topics: Animals; Gene Expression Profiling; Gene Expression Regulation, Plant; Gene Ontology; Herbivory; Larva; Oviposition; Plant Growth Regulators; Propanols; Protease Inhibitors; Solanum; Spodoptera; Transcription, Genetic
PubMed: 30545097
DOI: 10.3390/ijms19124008