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Scientific Reports Feb 2021The information that female insects perceive and use during oviposition site selection is complex and varies by species and ecological niche. Even in relatively...
The information that female insects perceive and use during oviposition site selection is complex and varies by species and ecological niche. Even in relatively unexploited niches, females interact directly and indirectly with conspecifics at oviposition sites. These interactions can take the form of host marking and re-assessment of prior oviposition sites during the decision-making process. Considerable research has focused on the niche breadth and host preference of the polyphagous invasive pest Drosophila suzukii Matsumura (Diptera: Drosophilidae), but little information exists on how conspecific signals modulate oviposition behavior. We investigated three layers of social information that female D. suzukii may use in oviposition site selection-(1) pre-existing egg density, (2) pre-existing larval occupation, and (3) host marking by adults. We found that the presence of larvae and host marking, but not egg density, influenced oviposition behavior and that the two factors interacted over time. Adult marking appeared to deter oviposition only in the presence of an unmarked substrate. These results are the first behavioral evidence for a host marking pheromone in a species of Drosophila. These findings may also help elucidate D. suzukii infestation and preference patterns within crop fields and natural areas.
Topics: Animals; Drosophila; Female; Fruit; Larva; Oviposition; Social Behavior
PubMed: 33589670
DOI: 10.1038/s41598-021-83354-2 -
Journal of Chemical Ecology Dec 2021Many pollinating insects exhibit flower constancy, i.e. they target flower species they have already experienced and fed from. While the insects might profit from...
Many pollinating insects exhibit flower constancy, i.e. they target flower species they have already experienced and fed from. While the insects might profit from reduced handling costs when revisiting similar flowers, flower constancy, in addition, is of benefit for the plants as it guarantees pollen transfer to conspecifics. Here we investigate whether the previous experience of an insect can also result in oviposition constancy, i.e. whether ovipositing on a given plant species will drive future oviposition preference in a female insect. We show that female hawkmoths (Manduca sexta), after having oviposited on a given plant species only once, indeed will prefer this plant in future oviposition choices. As oviposition preference is even affected 24 h after the moth has oviposited on a given plant, long term memory seems to be involved in this oviposition constancy. Our data furthermore suggest that, as shown for flower constancy, ovipositing moths increase their handling efficiency by targeting those host plants they have already experienced.
Topics: Animals; Female; Food Chain; Manduca; Memory, Long-Term; Oviposition; Plant Leaves; Species Specificity
PubMed: 34546516
DOI: 10.1007/s10886-021-01309-3 -
Reproductive Biology and Endocrinology... Jul 2013Egg laying in Magang geese is characterized by extended interruption between clutches and lowing laying rate. Both the ovarian follicular development and ovulation...
BACKGROUND
Egg laying in Magang geese is characterized by extended interruption between clutches and lowing laying rate. Both the ovarian follicular development and ovulation characteristics, and the associated endocrine and molecular regulatory mechanisms involved are poorly understood, but could be important for guiding development of molecule aided selection of egg laying performances in geese. This study, therefore, recorded egg-laying characteristics of Magang geese, and the endocrine and molecular regulatory mechanisms of ovarian follicular development, maturation, and ovulation in Magang geese.
METHODS
Oviposition, ovarian follicle development, and reproductive hormone and gene expression profiles were observed in a small flock of Magang geese.
RESULTS
Greater than 73% of eggs were laid during the day. The average oviposition interval was 46.8 h (36-55 h). It took approximately 18 days for large white follicles to develop into mature F1 follicles; follicular growth was exponential. LHR expression levels increased from the small to the large mature follicles, but FSHR expression decreased in the granulosa and thecal layers. As the follicles matured, inhibin alpha and inhibin betaA expression increased in the granulosa layer. Activin IR, activin IIRA, activin IIRB, and beta-glycan expressions also increased as the follicles increased in size, but were more abundantly expressed in the thecal than in the granulosa layers. During the oviposition cycle, plasma concentrations of gonadal hormones decreased rapidly, whereas the level of PGFM peaked around ovulation. The profiles of activin, inhibin, follistatin, estradiol, and progesterone leading to ovulation were characterized.
CONCLUSIONS
The molecular and endocrine mechanisms that regulate follicular development in Magang geese are similar to those in chickens. Moreover, gonadotropin regulation and interaction between activin, inhibin, and follistatin secretion may govern 3-stage maturation in the final preovulatory follicles in Magang geese. The rapid rebound of post-ovulatory secretions of inhibin and follistatin may inhibit recruitment of new SYF recruitment once a sequence of eggs is started, and may limit the egg clutch size to no more than the number of LYFs present before the first sequence egg.
Topics: Animals; Eggs; Female; Geese; Gene Expression Regulation; Hormones; Ovarian Follicle; Oviposition; Ovulation
PubMed: 23855623
DOI: 10.1186/1477-7827-11-65 -
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 -
Cell Reports Feb 2018Female hawkmoths, Manduca sexta, use olfactory cues to locate nectar sources and oviposition sites. We investigated if the behavioral significance of odorants is...
Female hawkmoths, Manduca sexta, use olfactory cues to locate nectar sources and oviposition sites. We investigated if the behavioral significance of odorants is represented already in the antennal lobe, the first olfactory neuropil of the insect's brain. Using in vivo calcium imaging, we first established a functional map of the dorsal surface of the antennal lobe by stimulating the moths with 80 ecologically relevant and chemically diverse monomolecular odorants. We were able to address 23 olfactory glomeruli, functional subunits of the antennal lobe, in each individual female. Next, we studied the relevance of the same odorants with two-choice experiments (odorant versus solvent) in a wind tunnel. Depending on odorant identity, naive moths made attempts to feed or to oviposit at the scented targets. A correlation of wind tunnel results with glomerular activation patterns revealed that feeding and oviposition behaviors are encoded in the moth's antennal lobe by the activation of distinct groups of glomeruli.
Topics: Animals; Arthropod Antennae; Behavior, Animal; Brain; Choice Behavior; Feeding Behavior; Female; Manduca; Neurons; Odorants; Oviposition
PubMed: 29490282
DOI: 10.1016/j.celrep.2018.01.082 -
Journal of Vector Ecology : Journal of... Jun 2014We investigated the oviposition behavior of Ae. aegypti and Ae. albopictus. In particular we examined whether small-scale site characteristics and the presence of...
We investigated the oviposition behavior of Ae. aegypti and Ae. albopictus. In particular we examined whether small-scale site characteristics and the presence of conspecifics or congeners altered oviposition by these mosquitoes. Various combinations of females of the two species were allowed to oviposit inside cages among either vegetation (potted plants) or structural components (wood and concrete blocks). Numbers of eggs deposited per female were compared between species, sides, and treatments. Most significant differences between treatments and species involved differences between single species and mixed species treatments. Ae. aegypti deposited more eggs/female in the vegetation side than in the structure side whereas the opposite pattern was evident for Ae. albopictus. Ae. aegypti females had higher frequency of skip oviposition than Ae. albopictus. An average of 63% of the containers in the two-species treatments contained eggs of both species, with more frequent joint occurrences observed in the treatment with three females of each species than in the treatments with one of each. Our results point to the existence of various interactions between gravid Ae. aegypti and Ae. albopictus females at or near the oviposition sites but further experimental work is necessary to fully characterize the interactions and their specific mechanisms.
Topics: Aedes; Animals; Female; Florida; Oviposition
PubMed: 24820572
DOI: 10.1111/j.1948-7134.2014.12086.x -
Tropical Biomedicine Dec 2013Insecticide applications are not particularly effective on Aedes aegypti mosquitoes which has been attributed to their 'closet' behaviour, or ability to rest in places...
Insecticide applications are not particularly effective on Aedes aegypti mosquitoes which has been attributed to their 'closet' behaviour, or ability to rest in places that remain unexposed to insecticides. Some researchers have suggested that insecticides repel mosquitoes, which would result in less exposure and increased dispersal. If repellence due to insecticides is a fact, acquiring a vector-borne disease, such as dengue, could legitimately be attributed to local vector control efforts and this would lead to restitution claims. This study thus investigated the effect of insecticide presence on mosquito behaviour indirectly via oviposition and directly via olfactory response. In all experiments, oviposition in each insecticide compared to its water and ethanol controls was not significantly different. This indicates that Ae. aegypti mosquitoes are not affected by insecticide presence and that increased dispersal is unlikely to be caused by vector control spraying.
Topics: Aedes; Animals; Female; Insecticides; Oviposition; Smell
PubMed: 24522139
DOI: No ID Found -
BMC Plant Biology Jan 2021Black gram [Vigna mungo (L)] seeds are a rich source of digestible protein and dietary fibre, both for human and animal consumption. However, the quality and quantity of...
BACKGROUND
Black gram [Vigna mungo (L)] seeds are a rich source of digestible protein and dietary fibre, both for human and animal consumption. However, the quality and quantity of the Vigna seeds are severely affected by bruchid beetles during storage. Therefore, analyses of the expression of the bruchid induced transcript dynamics in black gram pods would be helpful to understand the underlying defense mechanism against bruchid oviposition.
RESULTS
We used the RNAseq approach to survey the changes in transcript profile in the developing seeds of a moderately resistant cultivar IC-8219 against bruchid oviposition using a susceptible cultivar T-9 as a control. A total of 96,084,600 and 99,532,488 clean reads were generated from eight (4 each) samples of IC-8219 and T-9 cultivar, respectively. Based on the BLASTX search against the NR database, 32,584 CDSs were generated of which 31,817 CDSs were significantly similar to Vigna radiata, a close relative of Vigna mungo. The IC-8219 cultivar had 630 significantly differentially expressed genes (DEGs) of which 304 and 326 genes up and down-regulated, respectively. However, in the T-9 cultivar, only 168 DEGs were identified of which 142 and 26 genes up and down-regulated, respectively. The expression analyses of 10 DEGs by qPCR confirmed the accuracy of the RNA-Seq data. Gene Ontology and KEGG pathway analyses helped us to better understand the role of these DEGs in oviposition mediated defense response of black gram. In both the cultivars, the most significant transcriptomic changes in response to the oviposition were related to the induction of defense response genes, transcription factors, secondary metabolites, enzyme inhibitors, and signal transduction pathways. It appears that the bruchid ovipositioning mediated defense response in black gram is induced by SA signaling pathways and defense genes such as defensin, genes for secondary metabolites, and enzyme inhibitors could be potential candidates for resistance to bruchids.
CONCLUSION
We generated a transcript profile of immature black gram pods upon bruchid ovipositioning by de novo assembly and studied the underlying defense mechanism of a moderately resistant cultivar.
Topics: Animals; Coleoptera; Disease Resistance; Gene Expression Profiling; Gene Expression Regulation, Plant; Host-Parasite Interactions; Oviposition; Plant Diseases; Quantitative Trait Loci; Vigna
PubMed: 33430784
DOI: 10.1186/s12870-020-02796-4 -
Journal of the American Mosquito... Sep 2022Glyphosate is one of the most common herbicides used to control weeds in the USA. This herbicide can impact the mosquito life cycle through being carried to mosquito...
Glyphosate is one of the most common herbicides used to control weeds in the USA. This herbicide can impact the mosquito life cycle through being carried to mosquito habitats by runoff. This study investigates the effects of glyphosate on the larval development and oviposition of a laboratory colony of Culex quinquefasciatus. Our experiments indicated that a concentration of 1 g/liter glyphosate was lethal to larval instars or the larvae impacted were either unable to molt to pupae or never emerged as adults. Larval instars exposed to 0.5 g/liter glyphosate experienced a similar impact; however, the larval stage was extended and pupation was considerably delayed. Mosquitoes oviposited in 0.5 g/liter glyphosate laid the same number of egg rafts as in water, but a considerably lower number of eggs exposed to glyphosate hatched as first instars. If gravid females laid their eggs in 1 g/liter glyphosate versus water, the difference between the 2 groups would be statistically significant and a very low number of eggs exposed to glyphosate could ever hatch into larvae. In an oviposition assay carried out in a cage with 3 choices of water, 0.5 g/liter, and 1 g/liter glyphosate, a higher number of egg rafts were laid in water, followed by 0.5 g/liter and 1 g/liter glyphosate concentrations, respectively. Our study indicated such a severe effect of glyphosate on all immature stages of Cx. quinquefasciatus that no adult could ever emerge.
Topics: Animals; Culex; Culicidae; Female; Glycine; Larva; Oviposition; Water; Glyphosate
PubMed: 35901290
DOI: 10.2987/22-7059 -
Nature Communications Aug 2022Making the appropriate responses to predation risk is essential for the survival of an organism; however, the underlying mechanisms are still largely unknown. Here, we...
Making the appropriate responses to predation risk is essential for the survival of an organism; however, the underlying mechanisms are still largely unknown. Here, we find that Drosophila has evolved an adaptive strategy to manage the threat from its parasitoid wasp by manipulating the oviposition behavior. Through perception of the differences in host search performance of wasps, Drosophila is able to recognize younger wasps as a higher level of threat and consequently depress the oviposition. We further show that this antiparasitoid behavior is mediated by the regulation of the expression of Tdc2 and Tβh in the ventral nerve cord via LC4 visual projection neurons, which in turn leads to the dramatic reduction in octopamine and the resulting dysfunction of mature follicle trimming and rupture. Our study uncovers a detailed mechanism underlying the defensive behavior in insects that may advance our understanding of predator avoidance in animals.
Topics: Animals; Drosophila; Female; Host-Parasite Interactions; Neurons; Octopamine; Oviposition; Wasps
PubMed: 35918358
DOI: 10.1038/s41467-022-32203-5