Oviposition Stimulants Research Articles

A review of the chemical ecology of the Cerambycidae (Coleoptera)

This review summarizes the literature related to the chemical ecology of the Cerambycidae and provides a brief overview of cerambycid biology, ecology, economic significance, and management. Beetles in the family Cerambycidae have assumed increasing prominence as pests of forest and shade trees, shrubs, and raw wood products, and as vectors of tree diseases. Exotic species associated with solid wood packing materials have been notable tree killers in North American urban and peri-urban forests. In forested ecosystems native species respond to disturbances such as fires and windstorms, and initiate the biodeterioration of woody tissue. Eggs are laid by females, on or through the bark surface of stem and branch tissue of moribund, recently killed or decomposing woody plants; larval cerambycids (roundheaded woodborers) typically feed in the phloem and later in the xylem. Females will also, in some cases, select living hosts, e.g. adult conifer and angiosperm trees, for oviposition. Research on the chemical ecology of over 70 species has revealed many examples of attractive kairomones (such as floral volatiles, smoke volatiles, trunk and leaf volatiles, and bark beetle pheromones), repellents and deterrents, oviposition stimulants, short- and long-range sex pheromones, and defensive substances. Emerging generalities are that attractants tend to be monoterpenoids and phenolic esters; oviposition stimulants are monoterpenoids and flavanoids; short-range sex pheromones are female-produced, methyl-branched cuticular hydrocarbons; and long-range sex pheromones are male-produced α-hydroxy ketones and (α,β)-diols ranging in length from 6 to 10 carbons. The latter compounds appear to originate from glands in the male thorax; putative defensive substances originate from metasternal secretory pores or mandibular glands. In one unusual case, a flightless, subterranean female that attacks sugar cane produces a sex pheromone that is derived from the amino acid isoleucine. With significantly more than 35,000 species of Cerambycidae worldwide, these generalities will be subject to change as more species are examined.

Responses of Teretrius nigrescens Toward the Dust and Frass of Its Prey, Prostephanus truncatus

Teretrius nigrescens is considered to be a specialized predator of Prostephanus truncatus, a serious pest of stored maize and dried cassava roots. Using a bait-bag behavioral bioassay, this investigation found T nigrescens to be strongly arrested by dust and frass produced by P. truncatus on maize, whereas responses to maize flour were weak. Attempts to increase the arrestiveness of flour by altering its physical properties (coarseness or particle size range) were unsuccessful. The arrestive property of dust/frass did not degrade with long-term storage nor did it volatilize or degrade with oven baking up to 150 degrees C. However, extraction with methanol and reapplication was successful in transferring the arrestive property from the dust/frass onto maize flour. The prey dust/frass also induced more oviposition than did maize flour, as judged by production of F1 offspring. The results provide strong evidence for the existence of a high boiling point compound(s) in P. truncatus dust/frass that acts as a contact kairomone for T nigrescens. This, or another compound(s) also seems to act as an oviposition stimulant for female T. nigrescens.

Secondary metabolites of the leaf surface affected by sulphur fertilisation and perceived by the diamondback moth

Summary. Oilseed rape, Brassica napus L. (cv Express), plants were grown under three different sulphur regimes: sulphur-free (S0), normal sulphur (Sn, normal field concentration) and a sulphur-rich (S+, 2 × concentration of Sn). We performed dual choice oviposition assays with the diamondback moth, Plutella xylostella, using real plants and, for the first time with this insect, artificial leaves sprayed with methanolic leaf-surface extracts. The results mirrored those of a separate study of preferences for whole plants. Females laid more eggs on surrogate leaves that were treated with Sn extracts than on S0 plants, while only a slight, not significant, difference was observed between extracts of normal and sulphur-rich plants. This shows that chemical compounds on the leaf surface mediate the oviposition preference and that the female insect can perceive the quality of the host-plants in terms of their fertilisation status. Since leaf volatiles are known to be oviposition stimulants, we investigated the effects of leaf-surface extracts on insect olfactory responses using electroantennograms (EAGs). In agreement with the behavioural data, we found that extracts of sulphur-treated plants yielded higher EAG amplitudes than the S0 extracts. Since the leaf content of the volatiles isothiocyanates is influenced by sulphur nutrition, we analysed the extracts for these compounds. Above the detection threshold of our GC-MS system, no isothiocyanates were found. Thus, other compounds present in the surface extracts must be perceived by the antenna. However, the HPLC analysis revealed 11 different glucosinolates. Progoitrin (2-Hydroxy-3-butenyl) and gluconapoleiferin (2-Hydroxy-4-pentenyl), which belong to the hydroxy-alkene class of glucosinolates, were the most abundant compounds. The total glucosinolate content sharply increased from S0 to Sn plants, whereas it was slightly lower in n versus S+ plants. Since it is known that glucosinolates can stimulate oviposition, it seems likely that the increased content we observed was influencing the insect preference in this study too.

Seasonal variation in Daucus carota leaf-surface and leaf-tissue chemical profiles

The purpose of this work was to document seasonal changes in leaf-surface and whole-leaf chemistry of Daucus carota cohorts that differed in life-cycle phenology (winter annual, annual, or biennial), with particular focus on compounds that serve as contact oviposition stimulants for Papilio polyxenes, the black swallowtail butterfly. Cohorts of carrot plants exhibiting different life-cycle phenologies were established, and plants from each cohort were sampled periodically over two growing seasons. Extracts of leaf surfaces and leaf tissues were analyzed using HPLC and were compared quantitatively for the content of chlorogenic acid (CA), luteolin-7-O-(6″-O-malonyl)-β-D-glucopyranoside (L7MG), and luteolin-7-glucoside (L7G). The pattern of seasonal variation in L7G and L7MG concentrations in leaf tissues of each cohort followed the predictions of the tissue value hypothesis: flavonoid concentrations are highest in the tissues of new alternate leaves of the reproductive shoot or in new spring foliage. Chlorogenic acid concentrations in leaf tissues increased throughout the growing season. Patterns of leaf-surface seasonal variation did not correlate with patterns in leaf-tissue chemistry for any carrot cohort. Rather, leaf-surface amounts of CA, L7G, and L7MG were highest at the point in the lifecycle when plants were differentiating or bolting.

A bioassay to evaluate the activity of chemical stimuli from grape berries on the oviposition of Lobesia botrana (Lepidoptera: Tortricidae).

A two-choice bioassay was developed to evaluate the role of host-plant berry compounds on the oviposition site acceptance of the generalist moth Lobesia botrana (Denis & Shiffermüller). A key feature was the lining of the bioassay arena with felt which focused oviposition on the test substrates. Initial experiments comparing substrates with different physical features indicated that smooth textures and spherical shapes with interstices favour oviposition. Artificial oviposition substrates were thus constructed with glass spheres in order to test the behavioural activity of grapevine berry extracts. Only polar extracts obtained by soaking berries in methanol or water stimulated oviposition (more eggs were laid on the extract-treated substrate than on the control substrate), whereas more apolar ones obtained with chloroform or hexane had no significant effect. The prior removal of epicuticular waxes from grape berries before extraction did not enhance the stimulatory activity of the methanol extract. The oviposition response to this extract was dose-dependent. It is concluded that polar compounds present on grape berries act as oviposition stimulants for L. botrana.

Role of Bacteria in Mediating the Oviposition Responses of <I>Aedes albopictus</I> (Diptera: Culicidae)

The responses of Aedes albopictus to sources of oviposition attractants and stimulants were evaluated with a behavioral bioassay in which females attracted to odorants emanating from water were trapped on screens coated with an adhesive. Gravid mosquitoes were attracted to volatiles from larval-rearing water and soil-contaminated cotton towels. Bacteria were isolated from these substrates and from an organic infusion made with oak leaves. Through fatty acid-methyl ester analyses, six bacterial isolates from larval-rearing water, two isolates from soil-contaminated cotton towels, and three isolates from oak leaf infusion were identified to species. The response of gravid mosquitoes to these isolates was also evaluated in behavioral bioassays. Water containing Psychrobacter immobilis (from larval-rearing water), Sphingobacterium multivorum (from soil-contaminated cotton towels), and an undetermined Bacillus species (from oak leaf infusion) elicited significantly higher oviposition than control water without bacteria. Only volatiles collected from larval rearing water elicited significant electroantennogram responses in females.

Ovipositional Responses of the Indianmeal Moth, <I>Plodia interpunctella</I> (Hübner) (Lepidoptera: Pyralidae) to Oils

The Indianmeal moth, Plodia interpunctella, is a serious pest on dried fruit and oil-rich food products, such as pet food, cereals, flour products, and candy bars. We examined the P. interpunctella oviposition on unscreened food dishes with whole-wheat kernels treated with one of 18 different oils diluted in hexane (oil-treated) compared with a second unscreened food dish with whole-wheat kernels treated with hexane only (control). For eight of the 18 oils, the same two-choice experiment was conducted with screened food dishes. We concluded that (1) total oviposition was significantly lower when food dishes were screened compared with experiments with unscreened dishes; (2) using unscreened food dishes, P. interpunctella females laid significantly more eggs in 17 types of oil-treated wheat compared with dishes with control wheat kernels; and (3) using screened food dishes, P. interpunctella females only laid significantly more eggs in walnut oil-treated wheat compared with dishes with control wheat kernels. A nine-choice experiment was conducted in a large arena with unscreened food dishes, in which one dish contained control wheat kernels and eight other food dishes contained wheat treated with different oils. In the nine-choice experiment, P. interpunctella females showed the strongest response to wheat kernels treated with oil from walnut. This study provides the basis for chemical identification of oviposition stimulants for P. interpunctella from food oils.

Conspecific Eggs and Bertha Armyworm,Mamestra configurata(Lepidoptera: Noctuidae), Oviposition Site Selection

The oviposition biology of the bertha armyworm, Mamestra configurata Walker, was studied with emphasis on the effect of conspecific eggs on oviposition site selection. Bertha armyworm lay clusters of up to 700 eggs, and larvae have feeding and growth habits similar to those of other Lepidoptera that gain advantages from feeding aggregations. In a field-cage experiment, multiple egg masses per leaf were noted, although the vast majority (85%+) of leaves available for oviposition received no eggs. A series of dual-choice laboratory experiments was conducted using paired excised leaves with and without eggs or egg-wash extracts. Females strongly preferred to oviposit on leaves with eggs of a different female than on leaves without eggs. However, females did not prefer leaves with their own eggs over control leaves without eggs. Gravid females also preferred leaves treated with a methanol egg-wash over leaves treated only with methanol, indicating that the source of oviposition stimulation may be chemically based. The potential relevance of these observations is discussed in the context of host-plant distribution and their exploitation by bertha armyworm.

Enhanced oviposition in the moth, Plodia interpunctella, after treatment with aminergic analogues

In many species of moths, including Plodia interpunctella, post-mating events include the cessation of sex pheromone communication and the initiation of oviposition. In a previous study we have shown that octopamine and several analogues inhibit the production of sex pheromone in the moth. The present study demonstrates that octopamine and two analogues, clonidine and 2-(2,6-dimethylanilino) imidazolidine induce oviposition by virgin females of P. interpunctella, to a comparable level to that of mated females. Moreover, octopamine caused a significant reduction in the percentage of fertile eggs laid by mated females. It is suggested that octopamine therefore, mimics both the responses that occur post-mating: suppression of sex pheromone biosynthesis and stimulation of oviposition.

Oviposition site selection and oviposition stimulation by conspecifics in the golden egg bug (Phyllomorpha laciniata): implications for female fitness

Phyllomorpha laciniata Vill. (Heteroptera, Coreidae) females lay eggs on the host plant and on the backs of conspecifics. Since egg survival is greater when eggs develop on the backs of conspecifics than when laid on plants, we predict that females should prefer to lay eggs on conspecifics. In addition, because conspecifics are a high-quality site that represents a limiting resource, females should experience oviposition stimulation upon an encounter with a conspecific. Our results reveal that, when both the host plant and conspecifics are available simultaneously, females lay eggs preferentially on conspecifics. The results also support the second prediction, since females housed with conspecifics lay more than twice the number of eggs than isolated females. Isolated females do not seem to retain eggs, suggesting that oviposition stimulation is the result of an acceleration of egg-maturation rates.

Phytochemical-mediated differential acceptance of four rutaceous plants by a swallowtail butterfly, Papilio polytes (Lepidoptera: Papilionidae).

Papilio polytes, a Rutaceae feeder, exploits only a few plant species as larval food plants in nature. To clarify the physiochemical factors underlying its narrow host range, we examined the acceptability of four rutaceous plants, Citrus depressa (a host plant) and other potential hosts, Fagara ailanthoides, Evodia meliifolia, and Orixa japonica, to ovipositing females of the butterfly. Female responses to the foliage, methanol extracts and partitioned fractions prepared from these plants were assayed for the presence of oviposition stimulants and/or deterrents. The foliage and methanol extracts of C. depressa and F. ailanthoides readily induced egg-laying, while those of E. meliifolia evoked weak responses from females. In contrast, ovipositing females never accepted O. japonica. Further experiments with fractions derived from the respective plants revealed that C. depressa and F. ailanthoides contained potent oviposition stimulant(s) and E. meliifolia, both moderate stimulant(s) and weak deterrent(s). Negative oviposition response to O. japonica proved to be ascribed to the presence of weak deterrent(s) and the lack of any appreciable stimulant(s). Larval survivorship on these plants was also recorded as an estimate of fitness. In good coincidence with female oviposition responses, both 1st- and 5th-stadium larvae performed well on C. depressa and F. ailanthoides, while larval performance appeared a little worse on E. meliifolia. On the other hand, the survivorships of two larval stadia on O. japonica differed greatly from each other: whereas the mortality of neonates was very high, 5th stadium larvae grew into pupae as well or better on this plant as compared to E. meliifolia. These results suggest that the four rutaceous plants are arrayed as follows in decreasing order of acceptability: C. depressa5F. ailanthoides.E. meliifolia. .O. japonica.

Stimulation of colony initiation and colony development inBombus terrestrisby adding a male pupa: the influence of age and orientation

Hibernated queens of Bombus terrestris must be stimulated to start egg laying while kept in confinement. In this study, the stimulating effect of a male pupa and the impact of the age and the fixation angle of the pupa was examined. Queens started egg laying very soon if they were provided with a young male pupa. It took queens longer to oviposit with increasing age of the supplied pupae. Moreover, queens that were provided with older pupae produced fewer eggcups and fewer workers in the first brood. Queens with a horizontally fixed pupa did better than with a vertical or oblique oriented pupa. Of the queens that were provided with a young pupa, 80% produced colonies. In contrast, only 30% of the queens that were provided with an old pupa produced a colony. In addition, the latter colonies performed worse during the entire period of colony development. In conclusion, providing one horizontally fixed young male pupa to a hibernated, single queen resulted in the production of good colonies. Bombus terrestris / oviposition stimulation / male pupae / colony foundation

Flavonoid function and activity to plants and other organisms.

Flavonoid compounds distribute widely in vascular plants and Bryophytes, and ca. 5,000 kinds have been reported as naturally occurring substances. Many biological activities of the flavonoids were found until now. They include pollinator attractants, oviposition stimulants, feeding attractants and deterrents, allelopathy and phytoalexins. This paper reviews function and activity of flavonoids against plants and other organisms.

Oviposition stimulants for the tropical swallowtail butterfly, Papilio polytes, feeding on a rutaceous plant, Toddalia asiatica.

In nature, Papilio polytes utilizes a limited range of rutaceous plants as hosts. We isolated and identified oviposition stimulants for the butterfly from the foliage of its primary host plant Toddalia asiatica. Females readily deposited eggs in response to a methanolic extract of the plant. Partition of the extract with organic solvents revealed that chemicals responsible for eliciting egg-laying resided in a water-soluble fraction. Further bioassay-guided fractionation of the active fraction by column chromatography, preparative TLC, and HPLC led to the isolation of two oviposition stimulants. One was isolated from an amphoteric fraction and identified as trans-4-hydroxy-N-methyl-L-proline [(-)-(2S,4R)-4-hydroxy-1-methyl pyrrolidine-2-carboxylic acid; HMP]. The other, isolated from an acidic fraction, was identified as 2-C-methyl-D-erythronic acid [(-)-(2R,3R)-2-methyl-2,3,4-trihydroxybutanoic acid; MEA]. HMP alone evoked significant oviposition-stimulatory activity, although this was much lower than that of the original water-soluble fraction. MEA, on the other hand, alone did not elicit positive responses from females. However, HMP, when assayed in combination with MEA, markedly enhanced the female response, and the mixture was as active in stimulating oviposition as were the original water-soluble fraction and the plant foliage. We conclude that HMP is a substance crucial for host recognition by females, while MEA is a synergistic stimulant involved in host recognition and/or preference.

FEMALE LIFE SPAN AND FERTILITY ARE INCREASED BY THE EJACULATES OF PREFERRED MALES

In animals with internal fertilization, sperm competition among males can favor the evolution of male ejaculate traits that are detrimental to females. Female mating preferences, in contrast, often favor traits in males that are beneficial to females, yet little is known about the effect of these preferences on the evolution of male ejaculates. A necessary condition for female preferences to affect the evolution of male ejaculate characteristics is that females select mates based on a trait correlated with ejaculate quality. Previous work has shown that females of the variable field cricket, Gryllus lineaticeps, prefer males that produce calling songs containing faster and longer chirps. In this study, we tested the hypothesis that females receive more beneficial ejaculates from preferred males. Females were placed on either a high- or a reduced-nutrition diet then mated twice to a male of known song phenotype. Females received only sperm and seminal fluid from males during these matings. There was no effect of male song phenotype on any fitness component for females on the high-nutrition diet. Reduced-nutrition females mated to males that produced preferred song types, however, lived longer, produced more eggs, produced more fertile eggs, and had a higher proportion of their eggs fertilized than those mated to other males. The life-span benefit was positively associated with male chirp duration, and the reproductive benefits were positively associated with male chirp rate. We explored two possible mechanisms for the life span and reproductive benefits. First, a path analysis suggested that part of the effect of male chirp duration on female life span may have been indirect; females mated to males that produced longer chirps showed delayed oviposition, and females that delayed oviposition lived longer. Males that produce longer chirps may thus transfer fewer or less potent oviposition stimulants to females in their seminal fluid. Second, there was a positive correlation between male chirp rate and the number of sperm transferred to females. The fertility benefit may thus have resulted from females receiving more sperm from males that produce faster chirps. Finally, there was a negative phenotypic correlation between male chirp rate and chirp duration, suggesting that females may have to trade off the life span and reproduction benefits when selecting a mate.

Chemical mediation of differential oviposition and larval survival on rutaceous plants in a swallowtail butterfly, Papilio polytes

Abstract Papilio polytes utilizes only a few plant species of Rutaceae as hosts in the field. We examined in detail the acceptability of Toddalia asiatica (a major host plant) and three other potential rutaceous hosts, Murraya paniculata, Melicope triphylla, and Phellodendron amurense, for ovipositing females of the butterfly. Female responses to the foliage, methanol extracts, and partitioned fractions from these plants were assayed for the presence of oviposition stimulants and/or deterrents. Larval survivorship on these plant species was also compared as an estimate of fitness. The foliage and a methanol extract of T. asiatica readily induced egg‐laying, while females responded moderately to the foliage and a methanol extract of P. amurense. By contrast, ovipositing females only marginally accepted Me. triphylla and completely rejected Mu. paniculata. Further experiments to test the biological activity of fractions derived from the respective plant species revealed that T. asiatica contains potent oviposition stimulant(s) and that weak stimulant(s) are present in P. amurense. Poor or negative oviposition responses to both Me. triphylla and Mu. paniculata proved to be attributable to strong deterrent(s) present in these plants. Larvae performed very well on T. asiatica and P. amurense, whereas larval mortality was much higher on Mu. paniculata and Me. triphylla, suggesting the involvement of antifeedant(s) or toxic substance(s) in these plants.

Resistência de genótipos de tomateiro ao ácaro rajado

Avaliou-se a resistência de genótipos de tomateiro selvagens [Lycopersicon pennellii (LA 716), L. hirsutum var. glabratum (PI 126449, PI 134417), L. hirsutum (PI 127826, PI 127827), L. peruvianum (CGO 6707), L. peruvianum var. dentatum (WYR 2020, LA 111), L. peruvianum var. glandulosum (LA 1113-1, LA 1113-2)] e comerciais [(L. esculentum) Gem Pride, Santa Clara, e híbridos Bruna VFN, Carmem, Fortaleza, Débora Plus VFN] ao ácaro rajado (Tetranychus urticae). O número médio de ovos, fases imaturas (larvas, protoninfas e deutoninfas) e adultos por folíolo foi contado; o índice de preferência para oviposição (IPO) foi calculado. O delineamento experimental foi blocos ao acaso, com 6 repetições. Os genótipos LA 716, PI 126449, PI 134417, PI 127827, PI 127826 e Gem Pride apresentaram não-preferência para oviposição do ácaro rajado, sendo deterrentes quanto à classificação do IPO, enquanto os genótipos LA 111, WYR 2020, LA 1113-2 e LA1113-1 foram os mais preferidos para a oviposição e foram considerados como estimulantes pelo IPO.

The chemical world of crucivores: lures, treats and traps

AbstractThe host ranges of several insects that are specialists on crucifers (Brassicaceae) are closely linked to the presence of glucosinolates in these plants. These glycosides often serve as stimulants for oviposition and/or feeding, while their volatile hydrolysis products may be attractants for several species. However, many crucifers produce additional secondary compounds that act as repellents, deterrents or toxins, which protect them from these insects. The widely different responses of the various crucifer specialists to these compounds reflect different degrees of adaptation to the plant defenses. Thus native insects are often unable to survive on introduced plants, although the ubiquitous glucosinolates may trigger oviposition ‘mistakes’. The success of highly invasive cruciferous weeds may be due in part to a lack of local herbivore adaptation to unique chemical constituents of these plants. However, the concentrations of secondary chemicals vary with season, environmental conditions, and geographical location. This could mean that windows of opportunity exist for utilization of introduced plants. Recent studies with garlic mustard, Alliaria petiolata, and wintercress, Barbarea vulgaris, in the USA have shown that these introduced plants are resistant to the native butterfly, Pieris napi oleracea. The combined effects of a flavone glycoside and a unique butenenitrile glycoside in the garlic mustard appear to be responsible for blocking feeding by this insect. Barbarea vulgaris is also resistant to the diamondback moth, Plutella xylostella, in North America and to the flea beetle, Phyllotreta nemorum, in Europe. Comparative studies indicate that common resistance mechanisms are involved and bioassays have been developed to elucidate the chemical nature of this resistance.

Fitness advantage from nuptial gifts in female fireflies

Abstract 1. In many insects, males provide nuptial gifts to females in the form of spermatophores, sperm‐containing structures produced by male accessory glands.2. The work reported here examined the influence of both spermatophore number and spermatophore size on female reproductive output in two related firefly beetles, Photinus ignitus and Ellychnia corrusca (Coleoptera: Lampyridae). Based on differences in adult diet, male spermatophores were predicted to increase female reproductive output to a greater extent in P. ignitus than in E. corrusca.3. Female fecundity was significantly higher in triply mated females than in singly mated females in both species, with no difference between mating treatments in female lifespan or egg hatching success. No effects of second male spermatophore size on fecundity, lifespan, or egg hatching success were detected in either species.4. These results suggest a direct fitness advantage from multiple mating for females in both species, although enhanced fecundity may be due either to allocation of spermatophore nutrients to eggs or to other substances transferred within the spermatophore acting as oviposition stimulants.

Did certain chemoreceptors for host plant stimuli in the cabbage root fly evolve as pheromone receptors?

The cabbage root fly possesses highly specialised and extremely sensitive receptors for “CIF”, a group of compounds present on cabbage leaves in very small amounts, and the strongest oviposition stimulants known. Here we present evidence that the same receptors are sensitive to a methanol extract of cabbage root fly eggs, which may contain the fly's host marking pheromone. Based on these results, the possible role of CIF in cabbage root fly behaviour and in cabbage plants is discussed.