The predatory bug Orius strigicollis shows a preference for egg-laying sites based on plant topography

Background Oviposition site selection is an important factor in determining the success of insect populations. Orius spp. are widely used in the biological control of a wide range of soft-bodied insect pests such as thrips, aphids, and mites. Orius strigicollis (Heteroptera: Anthocoridae) is the dominant Orius species in southern China; however, what factor drives its selection of an oviposition site after mating currently remains unknown. Methods Here, kidney bean pods (KBPs) were chosen as the oviposition substrate, and choice and nonchoice experiments were conducted to determine the preferences concerning oviposition sites on the KBPs of O. strigicollis. The mechanism of oviposition behavior was revealed through observation and measurement of oviposition action, the egg hatching rate, and the oviposition time. Results We found that O. strigicollis preferred the seams of the pods for oviposition, especially the seams at the tips of the KBPs. Choice and nonchoice experiments showed that females did not lay eggs when the KBP tail parts were unavailable. The rates of egg hatching on different KBP parts were not significantly different, but the time required for females to lay eggs on the tip seam was significantly lower. Decreased oviposition time is achieved on the tip seam because the insect can exploit support points found there and gain leverage for insertion of the ovipositor. Discussion The preferences for oviposition sites of O. strigicollis are significantly influenced by the topography of the KBP surface. Revealing such behavior and mechanisms will provide an important scientific basis for the mass rearing of predatory bugs.

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Social signals mediate oviposition site selection in Drosophila suzukii

Scientific Reports ◽

10.1038/s41598-021-83354-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Johanna E. Elsensohn ◽

Marwa F. K. Aly ◽

Coby Schal ◽

Hannah J. Burrack

Keyword(s):

Site Selection ◽

Oviposition Behavior ◽

Oviposition Site ◽

Invasive Pest ◽

Oviposition Site Selection ◽

Social Signals ◽

Drosophila Suzukii ◽

Egg Density ◽

Behavioral Evidence ◽

Oviposition Sites

AbstractThe 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.

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Drosophila suzukii avoidance of microbes in oviposition choice

10.1101/2020.09.05.284166 ◽

2020 ◽

Author(s):

Airi Sato ◽

Kentaro M. Tanaka ◽

Joanne Y. Yew ◽

Aya Takahashi

Keyword(s):

Microbial Growth ◽

Chemical Cues ◽

Egg Laying ◽

Oviposition Site ◽

Site Preference ◽

Drosophila Suzukii ◽

Oviposition Choice ◽

Oviposition Site Preference ◽

Oviposition Substrate ◽

Oviposition Sites

AbstractWhile the majority of Drosophila species lay eggs onto fermented fruits, females of D. suzukii pierce the skin and lay eggs into ripening fruits using their serrated ovipositors. The changes of oviposition site preference must have accompanied this niche exploitation. In this study, we established an oviposition assay to investigate the effects of commensal microbes deposited by conspecific and heterospecific individuals, and showed that presence of microbes on the oviposition substrate enhances egg-laying of D. melanogaster and D. biarmipes, but discourages that of D. suzukii. This result suggests that a drastic change has taken place in the lineage leading to D. suzukii in how females respond to chemical cues produced by microbes. We also found that hardness of the substrate affects the response to microbial growth, indicating that mechanosensory stimuli interact with chemosensory invoked decisions to select or avoid oviposition sites.

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Forced Egg Laying Method to Establish F1 Progeny from Field Populations and Laboratory Strains of Anopheles Mosquitoes (Diptera: Culicidae) in Thailand

Journal of Medical Entomology ◽

10.1093/jme/tjab105 ◽

2021 ◽

Author(s):

Amonrat Panthawong ◽

Chutipong Sukkanon ◽

Ratchadawan Ngoen-Klan ◽

Jeffrey Hii ◽

Theeraphap Chareonviriyaphap

Keyword(s):

Adult Emergence ◽

Egg Laying ◽

Malaria Vectors ◽

Hatching Rate ◽

Sampling Effort ◽

Transparent Plastic ◽

Egg Hatching ◽

Test Species ◽

Anopheles Mosquitoes ◽

F1 Progeny

Abstract Successful monitoring of physiological resistance of malaria vectors requires about 150 female mosquitoes for a single set of tests. In some situations, the sampling effort is insufficient due to the low number of field-caught mosquitoes. To address this challenge, we demonstrate the feasibility of using the forced oviposition method for producing F1 from field-caught Anopheles mosquitoes. A total of 430 and 598 gravid Anopheles females from four laboratory strains and five field populations, respectively, were tested. After blood feeding, gravid mosquitoes were individually introduced into transparent plastic vials, containing moistened cotton balls topped with a 4 cm2 piece of filter paper. The number of eggs, hatching larvae, pupation, and adult emergence were recorded daily. The mean number of eggs per female mosquito ranged from 39.3 for Anopheles cracens to 93.6 for Anopheles dirus in the laboratory strains, and from 36.3 for Anopheles harrisoni to 147.6 for Anopheles barbirostris s.l. in the field populations. A relatively high egg hatching rate was found in An. dirus (95.85%), Anopheles minimus (78.22%), and An. cracens (75.59%). Similarly, a relatively high pupation rate was found for almost all test species ranging from 66% for An. minimus to 98.7% for Anopheles maculatus, and lowest for An. harrisoni (43.9%). Highly successful adult emergence rate was observed among 85–100% of pupae that emerged in all tested mosquito populations. The in-tube forced oviposition method is a promising method for the production of sufficient F1 progeny for molecular identification, vector competence, insecticide resistance, and bioassay studies.

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Reproduction in an Introduced Population of Elaphe schrenckii (Strauch, 1873) in Eelde, the Netherlands

Russian Journal of Herpetology ◽

10.30906/1026-2296-2020-27-6-325-333 ◽

2020 ◽

Vol 27 (6) ◽

pp. 325-333

Author(s):

Richard R. J. H. Struijk ◽

Rémon Ter Harmsel ◽

Daesik Park

Keyword(s):

The Netherlands ◽

Release Site ◽

Mean Value ◽

Limiting Factor ◽

Hatching Rate ◽

Egg Hatching ◽

Field Surveys ◽

Initial Release ◽

Continuous Presence ◽

Oviposition Sites

In 1994 an unknown number of captive bred Russian rat snakes, Elaphe schrenckii (Strauch, 1873) were introduced near Groningen Airport Eelde (Drenthe Province), the Netherlands. Research in 2016/2017 confirmed that the species has become established and is expanding slowly, as recent sightings are known at distances up to 5.3 km from the initial release site. Although the continuous presence over two decades and sightings of different life stages of E. schrenckii specimens indicate successful reproduction, no reproductive data existed. To gain more insight, we conducted field surveys between 2014 and 2016 to collect data on oviposition sites and reproduction. Eggs of E. schrenckii were encountered in three compost heaps. Twenty-two clutches were found in these heaps in total, comprising a total of 332 eggs. Additionally, 42 loose eggs were found, totaling the number of retrieved eggs to 374. Minimum clutch sizes range from 10 – 21 eggs and average 15.1 ± 3.2 eggs (N = 22). Total individual egg hatching rate is 87.8% (N = 271). Clutch hatching rate varied between 46.2% and 100% with a mean value of 86.7 ± 18.8% (N = 16). Our findings indicate the importance of compost heaps for this species regarding reproduction as suitable sites for oviposition within this non-native range. Also, fecundity does not seem to be negatively affected by conditions in its invasive range; clutch size is on the high side. Because hatching rates can be high, its reproduction does not seem to be a limiting factor for further expansion within Eelde and surroundings.

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Toxicity and Sublethal Effect of Farnesyl Acetate on Diamondback Moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae)

Insects ◽

10.3390/insects12020109 ◽

2021 ◽

Vol 12 (2) ◽

pp. 109

Author(s):

Norazila Yusoff ◽

Idris Abd Ghani ◽

Nurul Wahida Othman ◽

Wan Mohd Aizat ◽

Maizom Hassan

Keyword(s):

Plutella Xylostella ◽

Sublethal Effects ◽

Diamondback Moth ◽

Sublethal Effect ◽

Sublethal Concentration ◽

Pupal Weight ◽

Control Group ◽

Hatching Rate ◽

Egg Hatching ◽

Female Ratio

The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is the most important pest of cruciferous vegetables worldwide. In this study, we evaluated the properties of selected farnesyl derivative compounds against P. xylostella. The toxicity and sublethal concentration (LC50) of farnesyl acetate, farnesyl acetone, farnesyl bromide, farnesyl chloride, and hexahydrofarnesyl acetone were investigated for 96 h. The leaf-dip bioassays showed that farnesyl acetate had a high level of toxicity against P. xylostella compared to other tested farnesyl derivatives. The LC50 value was 56.41 mg/L on the second-instar larvae of P. xylostella. Then, the sublethal effects of farnesyl acetate on biological parameters of P. xylostella were assessed. Compared to the control group, the sublethal concentration of farnesyl acetate decreased pupation and emergence rates, pupal weight, fecundity, egg hatching rate, female ratio, and oviposition period. Furthermore, the developmental time of P. xylostella was extended after being exposed to farnesyl acetate. Moreover, the application of farnesyl acetate on P. xylostella induced morphogenetic abnormalities in larval–pupal intermediates, adults that emerged with twisted wings, or complete adults that could not emerge from the cocoon. These results suggested that farnesyl acetate was highly effective against P. xylostella. The sublethal concentration of farnesyl acetate could reduce the population of P. xylostella by increasing abnormal pupal and adults, and by delaying its development period.

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Structural comparison of the rostra of two species of weevils coexisting on Ailanthus altissima: the response to ecological demands of egg deposition

BMC Ecology and Evolution ◽

10.1186/s12862-021-01824-7 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Ganyu Zhang ◽

Wenjuan Guo ◽

Xiaoyi Wang ◽

Qian Wang ◽

Jin Cui ◽

...

Keyword(s):

Adaptive Radiation ◽

Egg Laying ◽

Ailanthus Altissima ◽

Structural Comparison ◽

Structural Differentiation ◽

Functional Potential ◽

Egg Deposition ◽

Adductor Muscles ◽

Structural Differences ◽

Oviposition Sites

Abstract Background Elongated rostra play an important role in the egg-laying of weevils, and its emergence plays a key role in the adaptive radiation of weevils. Eucryptorrhynchus scrobiculatus Motschulsky and E. brandti Harold co-occur on the same only host Ailanthus altissima, while their oviposition sites are different. In order to understand the adaptation between the rostra of the two weevils and their oviposition sites, the structural differentiation of the rostra in E. scrobiculatus and E. brandti was compared. Results The present study reveals that: (1) The rostra length of E. scrobiculatus and E. brandti was found to be correlated with body size, larger weevils have a correspondingly longer rostrum. The increase of rostra length may be a byproduct of larger weevils. (2) There were significant differences in the external shape of the two rostra, especially the shape of the mandibles of the mouthparts at the apex of the rostra used to excavate an oviposition cavity. (3) There was no difference in the size of the abductor muscles that control the extension of the mandibles, but there were significant differences in the size of the adductor muscles that control the contraction of the mandibles. Conclusions These structural differences reflect the functional potential ovipositional tactics of rostra, which is considered to be a response to the ecological demands of egg deposition, and also provide new insights into the coexistence of two weevil species in the same host A. altissima.

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logjam Encodes a Predicted EMP24/GP25 Protein That Is Required for Drosophila Oviposition Behavior

Genetics ◽

10.1093/genetics/164.1.173 ◽

2003 ◽

Vol 164 (1) ◽

pp. 173-186

Author(s):

Ginger E Carney ◽

Barbara J Taylor

Keyword(s):

Intracellular Trafficking ◽

Oviposition Behavior ◽

Egg Laying ◽

P Element ◽

Female Reproduction ◽

Multiple Functions ◽

Cytoplasmic Vesicles ◽

Egg Chambers ◽

Low Levels ◽

Overlapping Transcripts

Abstract A newly characterized Drosophila melanogaster gene, logjam (loj), functions in female reproduction by modulating oviposition behavior. The locus encodes at least six overlapping transcripts with unique 5′ ends. P-element mutants that express very low levels of loj transcripts are unable to oviposit mature eggs. This phenotype can be rescued by the introduction of a transgene expressing the most abundant loj transcript. As for many genes that specify behavioral outputs, loj is present in the adult central nervous system (CNS). Interestingly, it is also observed in vitellogenic egg chambers, suggesting that there may be multiple functions for this gene in egg-laying behavior. loj encodes a predicted protein with homology to the EMP24/GP25 transmembrane components of cytoplasmic vesicles and likely functions in intracellular trafficking.

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Responses of insect pests, pathogens, and invasive plant species to climate change in the forests of northeastern North America: What can we predict?This article is one of a selection of papers from NE Forests 2100: A Synthesis of Climate Change Impacts on Forests of the Northeastern US and Eastern Canada.

Canadian Journal of Forest Research ◽

10.1139/x08-171 ◽

2009 ◽

Vol 39 (2) ◽

pp. 231-248 ◽

Cited By ~ 268

Author(s):

Jeffrey S. Dukes ◽

Jennifer Pontius ◽

David Orwig ◽

Jeffrey R. Garnas ◽

Vikki L. Rodgers ◽

...

Keyword(s):

Climate Change ◽

Plant Species ◽

Invasive Plant ◽

Insect Pests ◽

Adelges Tsugae ◽

Pest Species ◽

Invasive Plant Species ◽

Eastern Canada ◽

Wide Range ◽

Nuisance Species

Climate models project that by 2100, the northeastern US and eastern Canada will warm by approximately 3–5 °C, with increased winter precipitation. These changes will affect trees directly and also indirectly through effects on “nuisance” species, such as insect pests, pathogens, and invasive plants. We review how basic ecological principles can be used to predict nuisance species’ responses to climate change and how this is likely to impact northeastern forests. We then examine in detail the potential responses of two pest species (hemlock woolly adelgid ( Adelges tsugae Annand) and forest tent caterpillar ( Malacosoma disstria Hubner)), two pathogens (armillaria root rot ( Armillaria spp.) and beech bark disease ( Cryptococcus fagisuga Lind. + Neonectria spp.)), and two invasive plant species (glossy buckthorn ( Frangula alnus Mill.) and oriental bittersweet ( Celastrus orbiculatus Thunb.)). Several of these species are likely to have stronger or more widespread effects on forest composition and structure under the projected climate. However, uncertainty pervades our predictions because we lack adequate data on the species and because some species depend on complex, incompletely understood, unstable relationships. While targeted research will increase our confidence in making predictions, some uncertainty will always persist. Therefore, we encourage policies that allow for this uncertainty by considering a wide range of possible scenarios.

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Sublethal effects of organophosphorus insecticide phoxim on patch time allocation and oviposition behavior in a parasitoid wasp Meteorus pulchricornis

Bulletin of Entomological Research ◽

10.1017/s0007485321000614 ◽

2021 ◽

pp. 1-10

Author(s):

Sheng Sheng ◽

Yan Song ◽

Sheraz Ahmad ◽

Jiao Wang ◽

Ying Shao ◽

...

Keyword(s):

Time Allocation ◽

Sublethal Effects ◽

Insect Pests ◽

Oviposition Behavior ◽

Host Density ◽

Parasitoid Wasp ◽

Patch Time Allocation ◽

Meteorus Pulchricornis ◽

Allocation Decisions ◽

Patch Residence Time

Abstract Parasitoid wasps are key agents for controlling insect pests in integrated pest management programs. Although many studies have revealed that the behavior of parasitic wasps can be influenced by insecticides, the strategies of patch time allocation and oviposition have received less attention. In the present study, we forced the endoparasitoid Meteorus pulchricornis to phoxim exposure at the LC30 and tested the foraging behavior within patches with different densities of the host, the larvae of the tobacco cutworm Spodoptera litura. The results showed that phoxim treatment can significantly increase the patch-leaving tendency of female wasps, while host density had no impact. The number of oviposition and the number of previous patch visits also significantly influenced the patch time allocation decisions. The occurrence of oviposition behavior was negatively affected by phoxim exposure; however, progeny production was similar among patches with different host densities. Phoxim exposure shaped the offspring fitness correlates, including longer durations from cocoon to adult wasps, smaller body size, and shorter longevity. The findings of the present study highlight the sublethal effects that reduce the patch residence time and the fitness of parasitoid offspring, suggesting that the application of phoxim in association with M. pulchricornis should be carefully schemed in agroecosystems.

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Identifying the Biological Characteristics Associated with Oviposition Behavior of Tea Leafhopper Empoasca onukii Matsuda Using the Blue Light Detection Method

Insects ◽

10.3390/insects11100707 ◽

2020 ◽

Vol 11 (10) ◽

pp. 707

Author(s):

Qi Yao ◽

Huining Zhang ◽

Long Jiao ◽

Xiaoming Cai ◽

Manqun Wang ◽

...

Keyword(s):

Blue Light ◽

Detection Method ◽

Oviposition Behavior ◽

Egg Laying ◽

Biological Characteristics ◽

Light Detection ◽

Tea Plantations ◽

Egg Density ◽

Theoretical Evidence ◽

Proven Method

Tea leafhopper (Empoasca onukii Matsuda) is amongst the key pests in tea plantations around the East Asian region. Stereomicroscopy is a conventional method used for detecting tea leafhopper eggs by dissecting the tender tissues. However, there is a need for a faster and more efficient method to directly observe and investigate intact eggs within tea shoots. The absence of a proven method limits research efforts for determining the oviposition behavior of E. onukii. Herein, we applied the blue light detection method (BLDM), a technique recently developed for other species, in order to detect E. onukii eggs directly and non-destructively within the tender shoot. In addition, we compared BLDM against the traditional stereomicroscope detection method (SMDM) for four tea cultivars. Notably, our results revealed that BLDM was precise and effective in measuring the egg laying quantity of E. onukii on intact tea shoots. Neither tea cultivars nor egg density in the tender shoot significantly affected the accuracy of BLDM. Furthermore, biological characteristics that have rarely been reported previously for E. onukii were investigated using the BLDM, including zygote duration, ovipositional rhythm, egg distribution within the tender shoot, and in different leaf positions, numbers of eggs laid by a single female daily, and laid by the entire generation. Therefore, these findings provide insights into the basic and theoretical evidence for the strategy and mechanism associated with the oviposition behavior of E. onukii.

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