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Oviposition Behavior in Lepidoptera
... The process of finding a suitable host by the adult insect involves the perception of multiple signals produced by the host plant (Renwick and Chew 1994, Carlsson et al. 1999, Tholl et al. 2006, Teles Pontes et al. 2010. In general, it is known that plants belonging to the same family emit a number of common and speciesspecific volatiles by which insects can differentiate between closely related species (Proffit et al. 2011, Megido et al. 2014. ...
The evolution of oviposition preference in insects is considered a key evolutionary strategy in the context of host–plant interaction. It is hypothesized that insects maximize the survival and fitness of the subsequent generations by preferring specific host plant(s), known as the “preference-performance hypothesis.” In this study, we tested whether adult host preference reflects the immature performance in an oligophagous insect, Phthorimaea absoluta Meyrick, a rapidly emerging invasive pest in Asia, Africa, and Europe. Based on a preliminary survey of the potential host plants of P. absoluta, we selected 6 Solanaceae species, namely, tomato, potato, eggplant, black nightshade, sweet pepper, and tobacco, for the oviposition preference studies. The results indicated that the tomato was the most preferred host in no-, dual- and multiple-choice assays, followed by potato, eggplant, and black nightshade. Subsequently, the insect life-table parameters were found to be superior on tomato compared to other hosts. The order of oviposition preference on the host plants was strongly correlated with the life-table parameters of P. absoluta. Thus, we provide clear evidence for the preference–performance hypothesis in the host selection behavior of P. absoluta. We also emphasize the necessity of conducting oviposition behavior research at various geographic locations to develop tailor-made integrated pest management programs.
... This finding aligns with the well-documented role of plant volatiles in guiding female insects to suitable oviposition sites and host plants for their offspring's development (Ansebo et al., 2004). The heightened sensitivity of females to these cues likely evolved to maximize reproductive success and ensure optimal host plant selection for egg-laying (Renwick and Chew, 1994;Burghardt et al., 2000). ...
The diamondback moth, Plutella xylostella L. (Lepidoptera: Plutellidae), is a major pest of Brassica crops worldwide. This study explores the application of Brassica spp. allelochemicals in trapping diamondback moth adults. The effectiveness of eight commercially obtained Brassica spp. volatiles has been investigated, including-(Z)-3-hexenyl acetate, cis-3-hexene-1-ol, β-pinene, sabinene, n-heptanal, allyl isothiocyanate, and Brassica non-volatiles-sinigrin and 4-methylsulfinylbutyl glucosinolate. These allelochemicals were tested at varying concentrations (10 to 90 μg/μL) in laboratory and open-screen cage environment trapping experiments. Cis-3-hexene-1-ol, (Z)-3-hexenyl acetate, sabinene, and β-pinene significantly attracted and trapped more female moths than controls; attraction decreased at higher concentrations. A 1:1 blend of cis-3-hexene-1-ol and (Z)-3-hexenyl acetate displayed optimal attraction in lab and open environment trials for the tested blends. Among the colors tested, green-colored containers proved to be the most effective for trapping. While the plant allelochemicals attracted diamondback moths, signs of non-target cabbage loopers were observed on treated plants. Y-tube olfactometer assays revealed that (Z)-3-hexenyl acetate and cis-3-hexene-1-ol were attractive to both male and female moths. These findings demonstrate the potential of Brassica spp. allelochemicals, particularly cis-3-hexene-1-ol and (Z)-3-hexenyl acetate, for trapping diamondback moths.
... This finding aligns with the well-documented role of plant volatiles in guiding female insects to suitable oviposition sites and host plants for their offspring's development (Ansebo et al., 2004). The heightened sensitivity of females to these cues likely evolved to maximize reproductive success and ensure optimal host plant selection for egg-laying (Renwick and Chew, 1994;Burghardt et al., 2000). ...
... They are attracted by the VOCs emitted by the plant, indicating its suitability as a host for their offspring. 3 Similarly, mosquitoes use olfactory cues to find suitable water bodies for oviposition. 4 They are attracted by the odour of stagnant water, indicating the availability of food sources for their larvae. ...
BACKGROUND
The litchi fruit borer Conopomorpha sinensis Bradley is a major destructive pest of litchi and longan plants in China, India and South East Asia. Given its strong olfactory‐based oviposition behaviour, interfering with the chemical communication between this insect pest and its host plant may serve as a potential control strategy. However, the chemical compounds associated with its egg‐laying behaviour remain poorly understood.
RESULTS
In this study, we investigated the olfactory preference of female C. sinensis for oviposition on intact mature fruits of the Feizixiao (FZX) and Guiwei (GW) varieties. Results showed that female C. sinensis preferred to lay eggs on FZX compared with GW fruits, and this preference was olfactory‐induced. In addition, we identified differences in the chemical composition of the volatile blend and proportions between FZX and GW fruits, with terpenes being the main volatile components contributing to this divergence. Compounds that induced electrophysiological activity in female borers were subsequently screened from FZX. d‐Limonene exhibited the strongest oviposition attraction among four candidates. Furthermore, this compound served as a volatile olfactory cue for recognition and orientation in female C. sinensis.
CONCLUSION
The results of this study provide a deeper understanding of the olfactory preferences of female C. sinensis for oviposition on specific litchi varieties. © 2024 Society of Chemical Industry.
... According to the preference-performance hypothesis, insect females should prefer to lay eggs on host plants that increase the performance and survival of their offspring (Jaenick 1978;Gripenberg et al. 2010). According toRenwick and Chew (1994), polyphagous insects have a greater opportunity to choose among potential plant hosts that offer highquality food; on the other hand, monophagous insects, such as CLM, have limited options for host-plant choice. In some cases, female's choice is not always bene cial for the offspring. ...
Coffee leaf miner (CLM) Leucoptera coffeella stands out as a primary insect pest of arabica coffee plants. Coffee breeding for CLM-resistance has used the species Coffea racemosa as gene donor for C. arabica , resulting in the development of the resistant commercial hybrid ‘Siriema AS1’. However, no previous study has characterized the resistance, and whether there is variation in the levels expressed in progenies of ‘Siriema’ to CLM. This study aimed to characterize the type, by antixenosis or antibiosis, and the levels of resistance in segregating progenies of ‘Siriema’ plants to CLM. Experiments were conducted under laboratory conditions with artificial infestation of CLM adults in oviposition cages, where dual-choice preference assays compared each tested ‘Siriema’ progeny with the susceptible cv. Arara. A follow-up no-choice assay evaluated five selected ‘Siriema’ progenies on the development of CLM compared to ‘Arara’. As main results, ‘Siriema’ progenies were equally susceptible to CLM oviposition, and were overall stimulant relative to cv. Arara. However, there was low CLM larval survival and injury intensity on the selected ‘Siriema’ genotypes, indicating the expression of moderate levels of antibiosis-resistance, while ‘Arara’ and one ‘Siriema’ progeny were moderately susceptible. These findings further our understanding on the type and levels of resistance in ‘Siriema’ genotypes, aiding the development of resistant coffee hybrids and deployment of management strategies to CLM.
Nine genotypes of kale (Brassica oleracea var. acephala) were evaluated for their oviposition preference and performance against Plutella xylostella based on their nutritional indices and oviposition decisions. Nutritional parameters in the fifth larval instar were measured using leaves of nine genotypes in petri dishes. Oviposition preferences on kale genotypes were studied using P. xylostela adults in an oviposition cage, adult moths were fed a 10% honey-water solution, with fresh kale leaves offered every two days until oviposition. Regarding the nutritional indices, our study found that fifth instar larvae showed the highest values for consumption index (CI ) on KALE-3 (1.23 ± 0.23 g/g/day) and lowest on KL-1 (0.34 ± 0.11 g/g/day). The highest approximate digestibility (AD) (88.25 ± 0.07%) was found on KALE-21 and lowest on KL-1 (39.62 ± 0.09%). The highest efficiency of conversion of digested food (ECD) and efficiency of conversion of ingested food (ECI) was found on the KL-1 genotype (94.93 ± 0.25%; 85.48 ± 0.17%), respectively while the lowest values were found on KL-8 (22.53 ± 0.14%) and KALE-3 (21.57 ± 0.08%), respectively. The highest Growth rate (GR) was recorded on KL- 1 (0.92 ± 0.06 g/g/day) and the lowest on KALE-3 (0.24 ± 0.13 g/g/day). Similarly, under choice tests P. xylostella showed the highest oviposition on KL-1 (77.80 ± 4.4), while as lowest on KALE-3 (11.8 ± 2.6), and in no-choice tests highest number of eggs was observed on KL-1 (295.80 ± 3.3) and KL-2 (257.80 ± 7.1) and the lowest number of eggs on KALE-21 (13.20 ± 3.0). Together, KALE-3 and KL-8 were found to be most resistant and KL-1 was found to be the most susceptible genotype against P. xylostella. This information will act as baseline work for all researchers across the globe as such a study was lacking for P. xylostella on kale.
Acraea terpsicore (Linnaeus, 1758) can utilize multiple host plants, particularly those in genus Passiflora, and poses a potential pest risk for introduced Passiflora plants and economically significant crops. In this study, the ovipositional preferences of an A. terpsicore population were investigated on four Passiflora species, including the wild host plant P. foetida, the fruit crop plant P. edulis, and two ornamental flower plants, P. × alata-caerulea and P. × coccinea-caerulea, as well as two non-Passiflora plants, Cucumis sativus and Vigna unguiculata. From a total of 4,059 eggs and 3,135 caterpillars, the majority of eggs were oviposited on P. foetida (50.63 %), followed by P. × coccinea-caerulea (23.40 %), P. × alata-caerulea (20.65 %), and P. edulis (5.32 %). Similarly, caterpillars were predominantly observed on P. foetida (38.66 %) and P. × coccinea-caerulea (38.50 %), followed by P. × alata-caerulea (17.86 %) and P. edulis (4.98 %). Meanwhile, neither eggs nor caterpillars were found on the non-Passiflora plants. Interestingly, the abundance of predatory arthropods mirrored the distribution of caterpillars. In addition, temperature and humidity strongly influenced the number of observed eggs and caterpillars. Although A. terpsicore preferred to oviposit on P. foetida, its caterpillars were equally abundant on P. × coccinea-caerulea. These differential ovipositional preferences and caterpillar proportions may be attributed to ovipositional preferences rather than caterpillars’ preferences. Although A. terpsicore is regarded as a non-pest species at present, this status may be altered if it encounters congeneric plants resembling its wild host plant within landscapes.
Cotton ( Gossypium sp.) is the one of the major commercial fibre crops cultivated across the country. The yield is severely affected by insect pests and diseases. Pink bollworm, Pectinophora gossypiella (Saunders, 1844) is one of the major insect pests threatening the cultivation of cotton. The major constraint limiting cotton production is resistance, which prevails to date due to the indiscriminate use of the insecticides and noncompliance of the refugia. Hence the status of the pest needs to be ascertained periodically to initiate timely and dynamic management tactics. For conducting laboratory screening, a higher number of individuals is the prime requirement, which is facilitated through mass-rearing techniques. We have evaluated different oviposition substrates like paper and muslin cloth for enhancing the recovery of eggs. Our results are quite promising and the use of black muslin cloth has shown a recovery of eggs on par with natural substrate (cotton twig). Adoption of the artificial substrate has huge potential in rearing techniques and avoids drawbacks like tissue drying, carry-over of diseases and reusability.
Understanding the evolutionary processes that influence fitness is critical to predicting species' responses to selection. Interactions among evolutionary processes including gene flow, drift and the strength of selection can lead to either local adaptation or maladaptation, especially in heterogenous landscapes. Populations experiencing novel environments or resources are ideal for understanding the mechanisms underlying adaptation or maladaptation, specifically in locally co‐evolved interactions. We used the interaction between a native herbivore that oviposits on a patchily distributed introduced plant that in turn causes significant mortality to the larvae to test for signatures of local adaptation in areas where the two co‐occurred. We used whole‐genome sequencing to explore population structure, patterns of gene flow and signatures of local adaptation. We found signatures of local adaptation in response to the introduced plant in the absence of strong population structure with no genetic differentiation and low genetic variation. Additionally, we found localized allele frequency differences within a single population between habitats with and without the lethal plant, highlighting the effects of strong selection. Finally, we identified that selection was acting on larval ability to feed on the plant rather than on females' ability to avoid oviposition, thus uncovering the specific ontogenetic target of selection. Our work highlights the potential for adaptation to occur in a fine‐grained landscape in the presence of gene flow and low genetic variation.
Identification of chemical compounds responsible for the oviposition behavior in a Rutaceae feeder,Papilio protenor demetrius, was undertaken with the epicarp of sour orange (Citrus natsudaidai) which exhibited potent stimulatory activity as did its leaves for egg-laying by the females. The stimulants were present in the hydrosoluble fraction, and the kairomonal activity displayed by the peel was regarded as originating from the synergistic effect of the total chemical complex. One of the active compounds was identified as a flavanone glycoside, naringin (naringenin-7β-neohesperidoside), which, although showing no appreciable effectiveness when bioassayed alone, elicited positive response at the concentration of 0.2% either when admixed with other unidentified components or provided the females had been conditioned with them in advance. Another flavanone glycoside, hesperidin (hesperetin-7β-rutinoside) that was contained in a trace amount in the peel also had a positive effect comparable to that of naringin under similar conditions, while their corresponding aglycones were less active or inactive. In contrast, a flavone glycoside, rhoifolin, coexisting in the peel, and some other flavones and flavonols tested as possible candidates for oviposition stimulants were all found entirely ineffective.
Soybean plant volatiles, extracted as steam distillates, significantly affected the behavior and biology of the cabbage looper,Trichoplusia ni (Hübner) (Lepidoptera: Noctuidae). Distillates from the susceptible Davis variety attractedT. ni larvae and female adults, whereas those from resistant PI 227687 plants repelled them. When mixed in an artificial diet, steam distillates from PI 227687 plants caused mortality of first-instar larvae. Adults emerging from pupae topically treated with 5 μg of such PI 227687 extractable showed developmental abnormalities. Larval feeding was significantly less on Davis leaves treated with PI 227687 volatiles as compared to solvent (acetone) or such Davis extractables. However, Davis volatiles on PI 227687 leaves did not increase larval feeding. HPLC analyses of steam distillates from susceptible Davis versus resistant PI 227687 indicated differences.
Methanol extracts of homogenized groundcherry,Physalis angulata, leaves increased egg deposition byHeliothis subflexa (Gn.) (HS) on treated tobacco plants (a nonhost) 8.5-fold over untreated controls. In doseresponse tests using whole-leaf washes of groundcherry leaves, the threshold of positive response vs. no response to the chemical stimulant was within one log dose unit when compared to the controls. This response was consistent whether the chemical was evaluated on plants in greenhouse-cage tests or in an olfactometer using pieces of broadcloth as the oviposition substrate. The olfactometer used allows year-round study of the behavioral effects of plant allelochemics on insect oviposition behavior in a controlled environment.
GravidPieris rapae butterflies oviposit on many, but not all, crucifers. Rejection ofErysimum cheiranthoides andCapsella bursa-pastoris was initially explained by the presence of chemical deterrents in the plants. Analyses and bioassays of plant extracts indicated the absence of oviposition stimulants inC. bursa-pastoris, but similar chemical separation ofE. cheiranthoides extracts revealed the presence of stimulants as well as deterrents. Choice tests illustrate how acceptance or rejection of a plant by an insect may depend on the balance of positive and negative chemical stimuli within the plant.
Females ofJunonia coenia (Nymphalidae), a specialist on plants that contain iridoid glycosides, were found to use aucubin and catalpol, iridoid glycosides typical of a host plant,Plantago lanceolata (Plantaginaceae), as oviposition cues. Incorporating dried ground leaf material or pure iridoid glycosides into agar disks proved to be a very effective method of testing. In no-choice tests and choice tests, females laid more eggs on disks withP. lanceolata leaf material or iridoid glycosides, compared to agar controls. There was variation among individual females in preference for disks withP. lanceolata leaf material versus disks with iridoid glycosides. Females given a choice of three different concentrations of iridoid glycoside (0.2, 0.5, 1.0%) in the agar disks and a control laid more eggs on the disk with the highest concentration of iridoid glycoside.
Avoidance ofErysimum cheiranthoides for oviposition byPieris rapae has been attributed to the presence of water-soluble deterrents. The active material was extracted inton-butanol and isolated by a series of HPLC separations. TLC of the active fraction and visualization of individual constituents with Kedde's reagent indicated that cardenolides are responsible for deterring oviposition. UV spectra were also characteristic of cardenolides. Bioassays of selected known cardenolides revealed a general lack of activity, except for cymarin, which was as strongly deterrent as the most prominent cardenolide isolated in pure form fromE. cheiranthoides. The results suggest that cardenolides in this plant can explain its escape from cabbage butterflies, but specific structural features of the glycosides are necessary for oviposition-deterring activity.
Previous experiments demonstrated an oviposition-deterring effect of larval frass in the Egyptian cotton leaf worm,Spodoptera littoralis (Boisd.). In this study, females were shown to perceive the oviposition-deterring substance(s) with their antennae. During dark, airtight, and cold (-10 °C) storage, the deterrent was persistent for at least 395 days. On the other hand, larval frass retained its activity for only two days when applied to cotton leaves. The deterrent activity of frass was independent of larval density. Frass of larvae reared at high densities deterred oviposition as well as frass of larvae feeding separately or in small groups. For significant oviposition deterrence, the minimum amount of frass was in the range of 5-10 mg frass per cotton leaf. An acetone extract of larval frass was highly deterrent, in contrast to extracts prepared with water, ethanol, chloroform, or pentane.
Pedicularis semibarbata is apparently an obligate hemiparasite of coniferous trees. It is also a facultative parasite ofLupinus fulcratus from which we find that it obtains quinolizidine alkaloids, principally α-isolupanine. As a result, a single population ofP. semibarbata contains both alkaloidrich and alkaloid-free plants. The butterflyEuphydryas editha naturally oviposits on both plant types. This butterfly population, which is the principal herbivore attackingP. semibarbata at this site, is known to contain two morphs. Individuals of a specialist morph discriminate when ovipositing among individualP. semibarbata plants and produce offspring that survive better on accepted than on rejected plants. Those of a generalist morph accept allP. semibarbata plants and produce offspring that survive equally well on plants accepted or rejected by the discriminating morph. Because of the existence of this complex variation among the butterflies, the presence of naturally laid eggs on alkaloid-containing plants still leaves the possibility that the alkaloids may defend the plants against the specialist morph. In experiments on both oviposition preference and larval performance in early instars, we failed to detect any correlation between alkaloid content of a plant and either its acceptability to or suitability for the discriminating morph of the insect. Alkaloid presence in the host-plant population, achieved through root parasitism, is currently neither subject to strong insect-mediated selection nor a major cause of selection on the insects.
Eggs ofPieris rapae (L.) contain a water- and methanol-soluble oviposition-deterring pheromone (ODP) that is avoided by ovipositing females offered treated and untreated cabbage leaves in a choice situation. Water extracts of female accessory glands also deter oviposition. Egg washes and gland extracts stimulate a contact chemoreceptor in sensilla on the fore tarsi. Electroantennogram (EAG) recordings show that antennal receptors respond to volatiles from conspecific eggs, but not to volatiles from eggs ofMamestra brassicae. No differences were detected between North American and European insects with regard to production and perception of ODP. These results differ from conclusions in the literature based upon field observations. It is concluded that this discrepancy in due to methodological differences.
Avoidance of some crucifer species by the crucifer specialist,Pieris rapae, has been attributed to the presence of oviposition deterrents in these plants. Studies on one such unacceptable plant,Erysimum cheiranthoides, have resulted in the isolation ofn-butanol-soluble deterrents from the alcoholic extract of foliage. The active fraction contained three cardiac glycosides, which were isolated by reversed-phase HPLC and by open column chromatography on silica gel. Chemical and spectral evidence (UV, [(1)H]NMR, and FAB-MS) led to the characterization of these compounds as erysimoside (1), erychroside (2), and erycordin (3). Erysimoside and erychroside were strongly deterrent toPieris rapae, but erycordin was inactive. Both active compounds have the same aglycone, strophanthidin (5) and the inner sugar in both cases is a 2,6-dideoxy hexose to which the outer sugar is attached at position C-4. These structural features, which are absent in the inactive compound (3), may represent specific requirements for oviposition deterrent activity.