Location of Host and Host Habitat by Fruit Fly Parasitoids

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Pascal Rousse

2012-11-01

Full Text Available Augmentative releases of parasitoids may be a useful tool for the area-wide management of tephritid pests. The latter are parasitized by many wasp species, though only a few of them are relevant for augmentative biocontrol purposes. To date, nearly all the actual or potential biocontrol agents for such programs are egg or larval Opiinae parasitoids (Hymenoptera: Braconidae. Here, we review the literature published on their habitat and host location behavior, as well as the factors that modulate this behavior, which is assumed to be sequential; parasitoids forage first for the host habitat and then for the host itself. Parasitoids rely on chemical, visual, and mechanical stimuli, often strongly related to their ecology. Behavioral modulation factors include biotic and abiotic factors including learning, climatic conditions and physiological state of the insect. Finally, conclusions and perspectives for future research are briefly highlighted. A detailed knowledge of this behavior may be very useful for selecting the release sites for both inundative/augmentative releases of mass-reared parasitoids and inoculative releases for classical biocontrol.

New parasitoid-predator associations: female parasitoids do not avoid competition with generalist predators when sharing invasive prey

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Chailleux, Anaïs; Wajnberg, Eric; Zhou, Yuxiang; Amiens-Desneux, Edwige; Desneux, Nicolas

2014-12-01

Optimal habitat selection is essential for species survival in ecosystems, and interspecific competition is a key ecological mechanism for many observed species association patterns. Specialized animal species are commonly affected by resource and interference competition with generalist and/or omnivorous competitors, so avoidance behavior could be expected. We hypothesize that specialist species may exploit broad range cues from such potential resource competitors (i.e., cues possibly common to various generalist and/or omnivorous predators) to avoid costly competition regarding food or reproduction, even in new species associations. We tested this hypothesis by studying short-term interactions between a native larval parasitoid and a native generalist omnivorous predator recently sharing the same invasive host/prey, the leaf miner Tuta absoluta. We observed a strong negative effect of kleptoparasitism (food resource stealing) instead of classical intraguild predation on immature parasitoids. There was no evidence that parasitoid females avoided the omnivorous predator when searching for oviposition sites, although we studied both long- and short-range known detection mechanisms. Therefore, we conclude that broad range cue avoidance may not exist in our biological system, probably because it would lead to too much oviposition site avoidance which would not be an efficient and, thus, beneficial strategy. If confirmed in other parasitoids or specialist predators, our findings may have implications for population dynamics, especially in the current context of increasing invasive species and the resulting creation of many new species associations.

Partial aphid resistance in lettuce negatively affects parasitoids.

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Lanteigne, Marie-Eve; Brodeur, Jacques; Jenni, Sylvie; Boivin, Guy

2014-10-01

This study investigated the effects of partial plant resistance on the lettuce aphid Nasonovia ribisnigri (Mosley) (Hemiptera: Aphididae), a major pest of cultivated lettuce (Lactuca sativa L.), and one of its parasitoids, Aphidius ervi Haliday (Hymenoptera: Braconidae). Aphids were reared on susceptible (L. sativa variety Estival; S) or partially resistant (Lactuca serriola L. PI 491093; PR) lettuce, and next parasitized by A. ervi females. Fitness proxies were measured for both aphids and parasitoids. Developmental time to adult stage took longer for alate and apterous aphids (an average of 3.5 and 1.5 additional days, respectively) on PR than on S lettuce, and fecundity of alate aphids reared on PR lettuce was reduced by 37.8% relative to those reared on S lettuce. Size (tibia length) and weight of aphids reared on PR lettuce were lower than for aphids reared on S lettuce from the third and second instar onward, respectively. Parasitism of aphids reared on PR plants resulted in lower parasitoid offspring emergence (-49.9%), lower adult female (-30.3%) and male (-27.5%) weight, smaller adult female (-17.5%) and male (-11.9%) size, and lower female fecundity (37.8% fewer eggs) than when parasitoids developed from aphids reared on S plants. Our results demonstrate that partial aphid resistance in lettuce negatively affects both the second and third trophic levels. Host plant resistance in cultivated lettuce may therefore create an ecological sink for aphid parasitoids.

Local and Landscape Drivers of Parasitoid Abundance, Richness, and Composition in Urban Gardens.

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Burks, Julia M; Philpott, Stacy M

2017-04-01

Urbanization negatively affects biodiversity, yet some urban habitat features can support diversity. Parasitoid wasps, an abundant and highly diverse group of arthropods, can inhabit urban areas and do well in areas with higher host abundance, floral resources, or local or landscape complexity. Parasitoids provide biological control services in many agricultural habitats, yet few studies have examined diversity and abundance of parasitoids in urban agroecosystems to understand how to promote conservation and function. We examined the local habitat and landscape drivers of parasitoid abundance, superfamily and family richness, and parasitoid composition in urban gardens in the California central coast. Local factors included garden size, ground cover type, herbaceous plant species, and number of trees and shrubs. Landscape characteristics included land cover and landscape diversity around gardens. We found that garden size, mulch cover, and urban cover within 500 m of gardens predicted increases in parasitoid abundance within gardens. The height of herbaceous vegetation and tree and shrub richness predicted increases in superfamily and family richness whereas increases in urban cover resulted in declines in parasitoid richness. Abundance of individual superfamilies and families responded to a wide array of local and landscape factors, sometimes in opposite ways. Composition of parasitoid communities responded to changes in garden size, herbaceous plant cover, and number of flowers. Thus, both local scale management and landscape planning may impact the abundance, diversity, and community composition of parasitoids in urban gardens, and may result in differences in the effectiveness of parasitoids in biological control. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

A survey of hymenopteran parasitoids of forest macrolepidoptera in the central Appalachians.

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Petrice, T R; Strazanac, J S; Butler, L

2004-04-01

In 1995 and 1996, we conducted a study of the hymenopteran parasitoids of macrolepidopteran larvae in the George Washington National Forest (GWNF), Augusta County, Virginia, and the Monongahela National Forest (MNF), Pocahontas County, West Virginia. Macrolepidopteran larvae were collected from canopy foliage and from under canvas bands placed around tree boles. A total of 115 macrolepidopteran species and 5,235 individual larvae were reared. Forty-two percent (2,221) of the larvae were gypsy moth, Lymantria dispar (L.) (Lymantriidae). A total of 43 primary and secondary (hyperparasitoid) hymenopteran parasitoid species were reared from 46 macrolepidopteran species. Hymenopteran families represented included Ichneumonidae (23 species), Braconidae (19), Eulophidae (6), Perilampidae (1), and Trigonalidae (1). We reared 41 and 28 parasitoid species from the GWNF and the MNF, respectively, with 19 species reared from both forests. Many parasitoid species were collected infrequently, suggesting that they are relatively rare on the sampled hosts. The introduced species Cotesia melanoscela (Ratzeburg) (Braconidae), and Euplectrus bicolor (Swederus) (Eulophidae) were among the most commonly reared parasitoids, the latter reared from native hosts. The four most commonly reared native parasitoids were Meteorus hyphantriae, Riley (Braconidae), Microplitis near hyphantriae (Ashmead) (Braconidae), Aleiodes preclarus Marsh & Shaw, and Euplectrus maculiventris (Westwood) (Eulophidae). A total of 53 new hymenopteran parasitoid-macrolepidopteran host records were documented. Results from this study will be used to evaluate long-term treatment effects of regional applications of Bacillus thuringiensis kurstaki, and the gypsy moth fungus Entomophaga maimaiga Humber, Shimazu & Soper on hymenopteran parasitoids of macrolepidopteran larvae.

HPLC sugar analysis reveals the nutritional state and the feeding history of parasitoids

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Steppuhn, A.; Wäckers, F.L.

2004-01-01

1. Adult parasitoids depend on sugar-rich foods such as nectar and honeydew to meet their energy requirements. Many laboratory studies have established fitness benefits of sugar feeding for parasitoids. 2. Nevertheless, we know little about the nutritional ecology of parasitoids in the field,

Systemic Imidacloprid Affects Intraguild Parasitoids Differently

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Roe, R. Michael; Bacheler, Jack S.

2015-01-01

Toxoneuron nigriceps (Viereck) (Hymenoptera, Braconidae) and Campoletis sonorensis (Cameron) (Hymenoptera, Ichneumonidae) are solitary endoparasitoids of the tobacco budworm, Heliothis virescens (Fabricius) (Lepidoptera, Noctuidae). They provide biological control of H. virescens populations in Southeastern US agricultural production systems. Field and greenhouse experiments conducted from 2011–2014 compared parasitism rates of parasitoids that developed inside H. virescens larvae fed on tobacco plants treated with and without imidacloprid. The parasitoids in our study did not have a similar response. Toxoneuron nigriceps had reduced parasitism rates, but parasitism rates of C. sonorensis were unaffected. Preliminary data indicate that adult female lifespans of T. nigriceps are also reduced. ELISA was used to measure concentrations of neonicotinoids, imidacloprid and imidacloprid metabolites in H. virescens larvae that fed on imidacloprid-treated plants and in the parasitoids that fed on these larvae. Concentrations were detectable in the whole bodies of parasitized H. virescens larvae, T. nigriceps larvae and T. nigriceps adults, but not in C. sonorensis larvae and adults. These findings suggest that there are effects of imidacloprid on multiple trophic levels, and that insecticide use may differentially affect natural enemies with similar feeding niches. PMID:26658677

Systemic Imidacloprid Affects Intraguild Parasitoids Differently.

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Sally V Taylor

Full Text Available Toxoneuron nigriceps (Viereck (Hymenoptera, Braconidae and Campoletis sonorensis (Cameron (Hymenoptera, Ichneumonidae are solitary endoparasitoids of the tobacco budworm, Heliothis virescens (Fabricius (Lepidoptera, Noctuidae. They provide biological control of H. virescens populations in Southeastern US agricultural production systems. Field and greenhouse experiments conducted from 2011-2014 compared parasitism rates of parasitoids that developed inside H. virescens larvae fed on tobacco plants treated with and without imidacloprid. The parasitoids in our study did not have a similar response. Toxoneuron nigriceps had reduced parasitism rates, but parasitism rates of C. sonorensis were unaffected. Preliminary data indicate that adult female lifespans of T. nigriceps are also reduced. ELISA was used to measure concentrations of neonicotinoids, imidacloprid and imidacloprid metabolites in H. virescens larvae that fed on imidacloprid-treated plants and in the parasitoids that fed on these larvae. Concentrations were detectable in the whole bodies of parasitized H. virescens larvae, T. nigriceps larvae and T. nigriceps adults, but not in C. sonorensis larvae and adults. These findings suggest that there are effects of imidacloprid on multiple trophic levels, and that insecticide use may differentially affect natural enemies with similar feeding niches.

Physiological correlates of sound localization in a parasitoid fly, Ormia ochracea

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Oshinsky, Michael Lee

A major focus of research in the nervous system is the investigation of neural circuits. The question of how neurons connect to form functional units has driven modern neuroscience research from its inception. From the beginning, the neural circuits of the auditory system and specifically sound localization were used as a model system for investigating neural connectivity and computation. Sound localization lends itself to this task because there is no mapping of spatial information on a receptor sheet as in vision. With only one eye, an animal would still have positional information for objects. Since the receptor sheet in the ear is frequency oriented and not spatially oriented, positional information for a sound source does not exist with only one ear. The nervous system computes the location of a sound source based on differences in the physiology of the two ears. In this study, I investigated the neural circuits for sound localization in a fly, Ormia ochracea (Diptera, Tachinidae, Ormiini), which is a parasitoid of crickets. This fly possess a unique mechanically coupled hearing organ. The two ears are contained in one air sac and a cuticular bridge, that has a flexible spring-like structure at its center, connects them. This mechanical coupling preprocesses the sound before it is detected by the nervous system and provides the fly with directional information. The subject of this study is the neural coding of the location of sound stimuli by a mechanically coupled auditory system. In chapter 1, I present the natural history of an acoustic parasitoid and I review the peripheral processing of sound by the Ormian ear. In chapter 2, I describe the anatomy and physiology of the auditory afferents. I present this physiology in the context of sound localization. In chapter 3, I describe the directional dependent physiology for the thoracic local and ascending acoustic interneurons. In chapter 4, I quantify the threshold and I detail the kinematics of the phonotactic

Dynamical System and Nonlinear Regression for Estimate Host-Parasitoid Relationship

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Ileana Miranda Cabrera

2010-01-01

Full Text Available The complex relationships of a crop with the pest, its natural enemies, and the climate factors exist in all the ecosystems, but the mathematic models has studied only some components to know the relation cause-effect. The most studied system has been concerned with the relationship pest-natural enemies such as prey-predator or host-parasitoid. The present paper shows a dynamical system for studying the relationship host-parasitoid (Diaphorina citri, Tamarixia radiata and shows that a nonlinear model permits the estimation of the parasite nymphs using nymphs healthy as the known variable. The model showed the functional answer of the parasitoid, in which a point arrives that its density is not augmented although the number host increases, and it becomes necessary to intervene in the ecosystem. A simple algorithm is used to estimate the parasitoids level using the priori relationship between the host and the climate factors and then the nonlinear model.

Predation on rose galls: parasitoids and predators determine gall size through directional selection.

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Zoltán László

Full Text Available Both predators and parasitoids can have significant effects on species' life history traits, such as longevity or clutch size. In the case of gall inducers, sporadically there is evidence to suggest that both vertebrate predation and insect parasitoid attack may shape the optimal gall size. While the effects of parasitoids have been studied in detail, the influence of vertebrate predation is less well-investigated. To better understand this aspect of gall size evolution, we studied vertebrate predation on galls of Diplolepis rosae on rose (Rosa canina shrubs. We measured predation frequency, predation incidence, and predation rate in a large-scale observational field study, as well as an experimental field study. Our combined results suggest that, similarly to parasitoids, vertebrate predation makes a considerable contribution to mortality of gall inducer larvae. On the other hand, its influence on gall size is in direct contrast to the effect of parasitoids, as frequency of vertebrate predation increases with gall size. This suggests that the balance between predation and parasitoid attack shapes the optimal size of D. rosae galls.

Niche separation of pollen beetle parasitoids

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Josef eBerger

2015-05-01

Full Text Available Species with similar resource requirements are commonly assumed to competitively exclude each other, unless they differentiate their ecological niches. Hence, parasitoid wasps that use the same host species need to find some way to avoid competition. The aim of this study was to identify the role of volatile cues from oilseed rape plants and the larval host in niche separation between three coexisting parasitoid species. We examined how Phradis interstitialis, Phradis morionellus and Tersilochus heterocerus, sympatric parasitoids of Brassicogethes aeneus, differ in their abundances, distribution on buds and flowers, and oviposition behavior in the field. Furthermore, we tested their preferences for odours from uninfested and infested oilseed rape plants in the bud and flowering stage, and their preferences for odours from three developmental stages of pollen beetle larvae in a two-choice olfactometer bioassay.P. interstitialis was active in the field early in the season, preferred odours of infested buds versus uninfested, and oviposited into buds which contained only pollen beetle eggs, while P. morionellus was active late in the season, preferred odours of infested buds as well as odours of infested flowers over uninfested, and oviposited into buds which contained only larvae. T. heterocerus was active throughout the season, and preferred odours of infested flowers over uninfested. Neither Phradis species were attracted to larval odours, whereas T. heterocerus was attracted to odours from first-instar pollen beetle larvae both in the absence of plant odours, and when presented simultaneously with uninfested plant odour.This suggests that the two Phradis species are separated on a temporal scale and that they parasitize different host stages, while the larval parasitoids P. morionellus and T. heterocerus are separated by choice of microhabitat. The former oviposits into larvae in buds, and the latter in flowers.

Ecosystem-based incorporation of nectar-producing plants for stink bug parasitoids

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Adult parasitoids of pest insects rely on floral resources for survival and reproduction but can be food-deprived in intensively managed agricultural systems lacking these resources. Stink bugs are serious pests of crops in southwest Georgia. Provisioning nectar-producing plants for parasitoids of s...

Habitats as complex odour environments: how does plant diversity affect herbivore and parasitoid orientation?

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Nicole Wäschke

Full Text Available Plant diversity is known to affect success of host location by pest insects, but its effect on olfactory orientation of non-pest insect species has hardly been addressed. First, we tested in laboratory experiments the hypothesis that non-host plants, which increase odour complexity in habitats, affect the host location ability of herbivores and parasitoids. Furthermore, we recorded field data of plant diversity in addition to herbivore and parasitoid abundance at 77 grassland sites in three different regions in Germany in order to elucidate whether our laboratory results reflect the field situation. As a model system we used the herb Plantago lanceolata, the herbivorous weevil Mecinus pascuorum, and its larval parasitoid Mesopolobus incultus. The laboratory bioassays revealed that both the herbivorous weevil and its larval parasitoid can locate their host plant and host via olfactory cues even in the presence of non-host odour. In a newly established two-circle olfactometer, the weeviĺs capability to detect host plant odour was not affected by odours from non-host plants. However, addition of non-host plant odours to host plant odour enhanced the weeviĺs foraging activity. The parasitoid was attracted by a combination of host plant and host volatiles in both the absence and presence of non-host plant volatiles in a Y-tube olfactometer. In dual choice tests the parasitoid preferred the blend of host plant and host volatiles over its combination with non-host plant volatiles. In the field, no indication was found that high plant diversity disturbs host (plant location by the weevil and its parasitoid. In contrast, plant diversity was positively correlated with weevil abundance, whereas parasitoid abundance was independent of plant diversity. Therefore, we conclude that weevils and parasitoids showed the sensory capacity to successfully cope with complex vegetation odours when searching for hosts.

Trichogramma chilotraeae PARASITOID TELUR Helicoverpa armigera (Hubner PADA POPULASI INANG RENDAH

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- Sujak

2011-03-01

Full Text Available Helicoverpa armigera Hubner is an insect pest of corn and cotton crops. Eggs are laid by  H. armigera imago on corn silk and cotton crops often have high mortality, mainly caused by egg parasitoid. H. armigera egg on various agroecosystem reported can  be parasited by at least 12 species of  Trichogrammatidae. The purpose of this study was to determine the diversity of  Trichogrammatidae family as  parasitoid eggs of  H. armigera on  low population. H. armigera egg sample taken from Asembagus, Lamongan and Blora at 1 m2 field  both monoculture and intercropping. Observation of parasitoids and predators  done at the Laboratory of Biological Control Balittas Malang. Parasitoid that appears preserved in the Hoyer medium for identification purposes. low population of  H. armigera Egg in Asembagus is  4 eggs/m2 in both monoculture maize and intercropping with 86-100 days after transplanting (DAT cotton and  4.5 egg/m2 on cotton monoculture and intercropping with 75  DAT soybean, while 2 eggs/m2 in the Lamongan and Blora corn agroecosystem. The dominant egg parasitoid in Asembagus is T. chilotraea, as well as in Lamongan and Blora.

Five new associations of parasitoids in potter wasps (Vespidae, Eumeninae

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Tiago H. Auko

2014-12-01

Full Text Available Five new associations of parasitoids in potter wasps (Vespidae, Eumeninae. New associations of host and parasitoids involving potter wasps: Toxophora leucon and Pleurochrysis sp. were found parasitizing Cyphomenes anisitsii, Chrysis sp. (gr. intricans was found parasitizing Minixi suffusum, Plega beardi was found parasitizing Montezumia pelagica sepulchralis and Macrosiagon sp. was found parasitizing Pachodynerus nasidens.

Fitness costs of intrinsic competition in two egg parasitoids of a true bug.

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Cusumano, Antonino; Peri, Ezio; Boivin, Guy; Colazza, Stefano

2015-10-01

Intrinsic competition in insect parasitoids occurs when supernumerary larvae develop in the same host as consequence of multiple ovipositions by females of the same species (intra-specific competition) or by females of different species (inter-specific competition). Studies on intrinsic competition have mainly focused on understanding the factors that play a role in the outcome of competition, while fitness-related effects for the parasitoid surviving the competition have been poorly investigated, especially in egg parasitoids. Interestingly, even the winning parasitoid can experience fitness costs due to larval development in a host in which multiple factors have been injected by the ovipositing females or released by their larvae. In this paper we studied fitness-related traits associated with intra- and inter-specific competition between Trissolcus basalis (Wollaston) and Ooencyrtus telenomicida (Vassiliev), the main egg parasitoids associated with the southern green stink bug Nezara viridula (L.) in Italy. We investigated the impact of intrinsic competition for the surviving parasitoid in terms of body size, developmental time, number and size of oocytes. Our results indicated that T. basalis adults did not experience fitness-related costs when surviving intra-specific competition; however, adults were smaller, took longer to develop and females produced fewer oocytes after surviving inter-specific competition. A different outcome was found for O. telenomicida where the emerging females were smaller, produced fewer and smaller oocytes when suffering intra-specific competition whereas no fitness costs were found when adults survived inter-specific competition. These results support the hypothesis that the impact of intrinsic competition in egg parasitoids depends on the severity of the competitive interaction, as fitness costs were more pronounced when the surviving parasitoid interacted with the most detrimental competitor. Copyright © 2015 Elsevier Ltd. All

Parasitoid-host endocrine relations: self-reliance or co-optation?

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Cole, T J; Beckage, N E; Tan, F F; Srinivasan, A; Ramaswamy, S B

2002-12-01

High titers of juvenile hormone (JH) maintain developmental arrest in Manduca sexta larvae parasitized by Cotesia congregata. Parasitized hosts exhibit up to 9.5 times greater amounts of total hemolymph JH (from 0.6+/-0.09 to 2.51+/-0.43ng/ml) compared to non-parasitized controls. Elevated titers are observed throughout the fifth instar, even beyond egression of the parasitoids on day 5. GC-MS analysis revealed that in hemolymph of unparasitized control larvae, JH I is the major homolog and levels of JH III are negligible; in parasitized individuals the amounts of JH I, II, and III rise, and JH III predominates. Neck ligation ensured separation of M. sexta's corpora allata from the posterior section, which contained most of the parasitoids in the infected insects. When the posterior region was sampled, JHs were not detected in the non-parasitzed larvae, but in those parasitized, JH III was found (1.98+/-0.29ng/ml, 24 h post-ligation). JH III was the only homolog produced and secreted by the parasitoid in in vitro culture. This is the first report stating that a parasitoid secretes JH III and may contribute, at least in part, to the circulating titer in the host hemocoel, concurrently promoting host production of JH I and II.

Influence of temperature on patch residence time in parasitoids: physiological and behavioural mechanisms

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Moiroux, Joffrey; Abram, Paul K.; Louâpre, Philippe; Barrette, Maryse; Brodeur, Jacques; Boivin, Guy

2016-04-01

Patch time allocation has received much attention in the context of optimal foraging theory, including the effect of environmental variables. We investigated the direct role of temperature on patch time allocation by parasitoids through physiological and behavioural mechanisms and its indirect role via changes in sex allocation and behavioural defences of the hosts. We compared the influence of foraging temperature on patch residence time between an egg parasitoid, Trichogramma euproctidis, and an aphid parasitoid, Aphidius ervi. The latter attacks hosts that are able to actively defend themselves, and may thus indirectly influence patch time allocation of the parasitoid. Patch residence time decreased with an increase in temperature in both species. The increased activity levels with warming, as evidenced by the increase in walking speed, partially explained these variations, but other mechanisms were involved. In T. euproctidis, the ability to externally discriminate parasitised hosts decreased at low temperature, resulting in a longer patch residence time. Changes in sex allocation with temperature did not explain changes in patch time allocation in this species. For A. ervi, we observed that aphids frequently escaped at intermediate temperature and defended themselves aggressively at high temperature, but displayed few defence mechanisms at low temperature. These defensive behaviours resulted in a decreased patch residence time for the parasitoid and partly explained the fact that A. ervi remained for a shorter time at the intermediate and high temperatures than at the lowest temperature. Our results suggest that global warming may affect host-parasitoid interactions through complex mechanisms including both direct and indirect effects on parasitoid patch time allocation.

KEMELIMPAHAN DAN KERAGAMAN JENIS PARASITOID HAMA PENGGULUNG DAUN PISANG ERIONOTA THRAX L. DI KABUPATEN LAMPUNG SELATAN

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Lestari Wibowo

2015-03-01

Full Text Available The abundance and diversity of the parasitoid of banana leaf skipper pest (Erionota thrax L. in South Lampung Regency. This research was conducted to determine the abundance, diversity, and parasitation ability of several parasitoids of the banana skipper or banana leafroller (Erionota thrax in South Lampung Regency. This research was carried out with a survey method by taking out samples of larvae and pupae of E. thrax in the District of Natar, Jati Agung, and Tanjung Bintang, South Lampung. Results of the survey showed that there were 8 types of parasitoids recovered from larvae or pupae of E. thrax, i.e. Brachymeria lasus (Chalcididae: Hymenoptera, B. thracis (Chalcididae: Hymenoptera, Charops sp. (Ichneumonidae: Hymenoptera, Casinaria sp. (Ichneumonidae: Hymenoptera, Xanthopimpla sp. (Ichneumonidae: Hymenoptera, Cotesia erionotae (Braconidae: Hymenoptera, and two parasitoids Diptera (Tachinidae and Sarcophagidae. The highest abundance of parasitoid was found in Tanjung Bintang with 171 parasitoids (index of diversity (H’ = 1.0256 and index of evenness (E = 0.5724. In Natar District, the abundance of parasitoid was 63 parasitoids, but it had a greater H’ value (1.4396 and E-value (0.7398. Meanwhile, in Jati Agung District, the abundance of parasitoid was 56 individuals but the value of H’ was also high, which was 1.012 with the value of E of 0.6064. The percentages of parasitation to the larvae and pupae E. thrax were 55.01% (Tanjung Bintang District, 31.68% (Natar District and 33.34% (Jati Agung District.

Mortality of Plutella xylostella (Lepidoptera, Plutellidae by parasitoids in the Province of Santa Fe, Argentina

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Isabel Bertolaccini

2011-09-01

Full Text Available Mortality of Plutella xylostella (Lepidoptera, Plutellidae by parasitoids in the Province of Santa Fe, Argentina. Plutella xylostella (Linnaeus, 1758 (Lepidoptera, Plutellidae larvae cause severe economic damage on cabbage, Brassica oleracea L. variety capitata (Brassicaceae, in the horticultural fields in the Province of Santa Fe, Argentina. Overuse of broad spectrum insecticides affects the action of natural enemies of this insect on cabbage. The objectives of this work were to identify the parasitoids of P. xylostella and to determine their influence on larva and pupa mortality. Weekly collections of larvae and pupae were randomly conducted in cabbage crops during spring 2006 and 2007. The immature forms collected were classified according to their developmental stage: L1 and L2 (Ls = small larvae, L3 (Lm = medium larvae, L4 (Ll = large larvae, pre-pupae and pupae (P. Each individual was observed daily in the laboratory until the adult pest or parasitoid emergence. We identified parasitoids, the number of instar and the percentage of mortality of P. xylostella for each species of parasitoid. Parasitoids recorded were: Diadegma insulare (Cresson, 1875 (Hymenoptera, Ichneumonidae, Oomyzus sokolowskii (Kurdjumov, 1912 (Hymenoptera, Eulophidae, Cotesia plutellae (Kurdjumov, 1912 (Hymenoptera, Braconidae and an unidentified species of Chalcididae (Hymenoptera. Besides parasitoids, an unidentified entomopathogenic fungus was also recorded in 2006 and 2007. In 2006, the most successful parasitoids were D. insulare and O. sokolowskii, while in 2007 only D. insulare exerted a satisfactory control and it attacked the early instars of the pest.

r and K strategies in some larval and pupal parasitoids of the gypsy moth.

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Barbosa, Pedro

1977-12-01

The investigations of the bionomics and parasitoid-host interactions of some gypsy moth parasitoids provide an opportunity to consider the role of r and K strategies in the life history of some tachinid and hymenopterous parasitoid species. Available historic data as well as results of recent studies are utilized in an attempt to evaluate the degree to which the data conform to this paradigm. Few studies have provided the information required to evaluate this concept particularly in a parasitoid complex. The concept of r and K also is discussed in relation to biological control strategies, and the implications of this analysis for those arguments are discussed.

The effects of host-feeding on stability of discrete-time host-parasitoid population dynamic models.

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Emerick, Brooks; Singh, Abhyudai

2016-02-01

Discrete-time models are the traditional approach for capturing population dynamics of a host-parasitoid system. Recent work has introduced a semi-discrete framework for obtaining model update functions that connect host-parasitoid population levels from year-to-year. In particular, this framework uses differential equations to describe the host-parasitoid interaction during the time of year when they come in contact, allowing specific behaviors to be mechanistically incorporated. We use the semi-discrete approach to study the effects of host-feeding, which occurs when a parasitoid consumes a potential host larva without ovipositing. We find that host-feeding by itself cannot stabilize the system, and both populations exhibit behavior similar to the Nicholson-Bailey model. However, when combined with stabilizing mechanisms such as density-dependent host mortality, host-feeding contracts the region of parameter space that allows for a stable host-parasitoid equilibrium. In contrast, when combined with a density-dependent parasitoid attack rate, host-feeding expands the non-zero equilibrium stability region. Our results show that host-feeding causes inefficiency in the parasitoid population, which yields a higher population of hosts per generation. This suggests that host-feeding may have limited long-term impact in terms of suppressing host levels for biological control applications. Copyright © 2015 Elsevier Inc. All rights reserved.

Parasitoid Wasps in Flower Heads of Asteraceae in the Brazilian Cerrado: Taxonomical Composition and Determinants of Diversity.

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Nascimento, A R; Almeida-Neto, M; Almeida, A M; Fonseca, C R; Lewinsohn, T M; Penteado-Dias, A M

2014-08-01

This study provides the first survey of the parasitoid fauna reared in flower heads of Asteraceae in the Brazilian cerrado. We investigated the relative importance of herbivore richness and plant species commonness to differences in parasitoid species richness among the plant species. A total of 15,372 specimens from 192 morphospecies belonging to 103 genera of Hymenoptera were reared from the flower heads of 74 Asteraceae species. Chalcidoidea and Ichneumonoidea were the most common superfamilies, with Eulophidae and Braconidae as the main families of parasitoid wasps. Singletons and doubletons accounted for 45% of total parasitoid species richness. The number of parasitoid species per plant species ranged from 1 to 67, and the variation in parasitoid species richness among plants was mainly explained by the number of sites in which the plants were recorded. This study shows that there is a highly diversified fauna of Hymenoptera parasitoids associated with flower heads of Asteraceae in the Brazilian cerrado. Our findings suggest that the accumulation of parasitoid species on plants is mainly determined by the regional commonness of plant species rather than the number of herbivore species associated with the plants.

Multisensory foraging by hymenopterous parasitoids

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Waeckers, F.L.

1994-01-01

The use of parasitoids as biological control agents is gaining interest as an environmentally sound alternative to the use of chemical insecticides. In order to extend and optimize biological control systems, it is essential to gain insight in the stimuli and mechanisms by which natural enemies

Light brown apple moth in California: a diversity of host plants and indigenous parasitoids.

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Wang, Xin-Geng; Levy, Karmit; Mills, Nicholas J; Daane, Kent M

2012-02-01

The light brown apple moth, Epiphyas postvittana (Walker), an Australia native tortricid, was found in California in 2006. A field survey of host plants used by E. postvittana was conducted in an urban region of the San Francisco Bay Area. An inspection of 152 plant species (66 families), within a 23-ha residential community, found E. postvittana on 75 species (36 families). Most (69 species) host plants were not Australian natives, but had a wide geographic origin; 34 species were new host records for E. postvittana. Heavily infested species were the ornamental shrubs Myrtus communis L., Pittosporum tobira (Thunb.) W.T. Aiton, Euonymus japonicus Thunb., and Sollya heterophylla Lindl. To survey for parasitoids, four urban locations were sampled, with E. postvittana collected from five commonly infested plants [M. communis, P. tobira, E. japonicus, Rosmarinus officinalis L., and Genista monspessulana (L.) L.A.S. Johnson]. Twelve primary parasitoid species and two hyperparasitoids were reared; the most common were the egg parasitoid Trichogramma fasciatum (Perkins), the larval parasitoids Meteorus ictericus Nees, and Enytus eureka (Ashmead), and the pupal parasitoid Pediobius ni Peck. Meteorus ictericus accounted for >80% of the larval parasitoids, and was recovered from larvae collected on 39 plant species. Across all samples, mean parasitism was 84.4% for eggs, 43.6% for larvae, and 57.5% for pupae. The results are discussed with respect to the potential for resident parasitoid species to suppress E. postvittana populations.

Encapsulation and Hemocyte Numbers in Crocidolomia pavonana and Spodoptera litura Fabricius (Lepidoptera Attacked by Parasitoid Eriborus argenteopilosus Cameron (Hymenoptera

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DAMAYANTI BUCHORI

2009-12-01

Full Text Available Eriborus argenteopilosus is the most important parasitoid attacking cabbage pest Crocidolomia pavonana in Indonesia. Previous studies proved that parasitoid encapsulation was found to be an important factor limiting the effectiveness of the parasitoid in controlling pest population in the field. Since 1998, we have conducted series studies to investigate encapsulation mechanism developed by hosts against parasitoid, responses of parasitoid toward encapsulation ability and to determine factors that may help parasitoid avoid encapsulation. Parasitoid responses were examined on two different hosts C. pavonana and Spodoptera litura. Our findings showed that parasitization level was found to be high both on C. pavonana and S. litura. Encapsulation occurred to be high in all larva stages of C. pavonana, in contrast encapsulation was recorded very low in all larvae stages of S. litura. We recorded that encapsulation in the larval body of C. pavonana was completed in 72 hours and mostly occurred in higher larval stage. Melanization was only recorded in encapsulated parasitoid inside larva body of C. pavonana, not in S. litura. We recorded that encapsulation increased blood cell number of both larvae C. pavonana and S. litura. Encapsulation may affect development of immature parasitoid. Weight of S. litura's pupae containing encapsulated parasitoid was found to be lower in S. litura, but not in C. pavonana. Our investigation also proved that superparasitism may help parasitoid avoid encapsulation.

Natural Distribution of Parasitoids of Larvae of the Fall Armyworm, Spodoptera frugiperda, in Argentina

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Gabriela Murúa, M.; Molina-Ochoa, Jaime; Fidalgo, Patricio

2009-01-01

To develop a better understanding of the natural distribution of the fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae), and to update the knowledge of the incidence of its complex of parasitoids. S. frugiperda, samplings in whorl-stage corn were carried out in provinces of Argentina from 1999 to 2003. S. frugiperda larvae were collected from corn in localities of the provinces of Tucumán, Salta, Jujuy, Santiago del Estero, La Rioja, Córdoba, San Luis, Chaco and Misiones. In each locality 30 corn plants were sampled and only larvae located in those plants were collected. The parasitoids that emerged from S. frugiperda larvae were identified and counted. The abundance of the parasitoids and the parasitism rate were estimated. The S. frugiperda parasitoids collected were Campoletis grioti (Blanchard) (Hymenoptera: Ichneumonidae), Chelonus insularis (Cresson) (Hymenoptera: Braconidae), Archytas marmoratus (Townsend) (Diptera Tachinidae) and/or A. incertus (Macquart), Ophion sp. (Hymenoptera: Ichneumonidae), Euplectrus platyhypenae Howard (Hymenoptera: Eulophidae), and Incamyia chilensis (Aldrich) (Diptera Tachinidae). C. grioti was the most abundant and frequent during the five-year survey. Similar diversity of parasitoids was obtained in all the provinces, with the exception of I. chilensis and E. platyhypenae that were recovered only in the province of Salta. In the Northwestern region, in Tucumán, C. grioti and species of Archytas were the most abundant and frequent parasitoids. On the contrary, in Salta and Jujuy Ch. insularis was the parasitoid most abundant and frequently recovered. The parasitism rate obtained in Tucumán, Salta and Jujuy provinces were 21.96%, 17.87% and 6.63% respectively with an average of 18.93%. These results demonstrate that hymenopteran and dipteran parasitoids of S. frugiperda occurred differentially throughout the Argentinian provinces and played an important role on the natural control of the S. frugiperda larval

Toxicity of chemicals commonly used in Indonesian vegetable crops to Liriomyza huidobrensis populations and the Indonesian parasitoids Hemiptarsenus varicornis, Opius sp., and Gronotoma micromorpha, as well as the Australian parasitoids Hemiptarsenus varicornis and Diglyphus isaea.

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Prijono, Djoko; Robinson, Michelle; Rauf, Aunu; Bjorksten, Tracey; Hoffmann, Ary A

2004-08-01

Liriomyza huidobrensis (Blanchard) and Liriomyza sativae (Blanchard) are important pests of vegetable crops in Indonesia and are likely to spread to neighboring countries. Three pesticides (dimehypo, abamectin, and cyromazine) are currently used to control these pests, but there is little information on their effectiveness against field populations and on their impact on parasitoids controlling Liriomyza species. The toxicity of these chemicals to L. huidobrensis and three common parasitoids (Hemiptarsenus varicornis Gerault, Opius sp., and Gronotoma micromorpha Perkins) was therefore evaluated in Indonesia with mortality laboratory assays. All three chemicals were effective against larvae of three populations of L. huidobrensis with different histories of chemical exposure. Dimehypo caused mortality in adult Opius sp., G. micromorpha, and H. varicornis, whereas abamectin was toxic only at concentrations substantially higher than the field rate. Cyromazine did not influence survival of the parasitoids. A commonly used fungicide, mancozeb, had no impact on parasitoid mortality. Trials were repeated with a strain of H. varicornis from Australia and a different parasitoid (Diglyphus isaea) recently found in Australia. Neither parasitoid was influenced by mancozeb or cyromazine. Abamectin applied at field rates caused some mortality among the adults of both species, but was less toxic than chlorpyrifos. Abamectin produced lower LC50s against Australian H. varicornis than against Indonesian H. varicornis. These results suggest that cyromazine can be incorporated into Liriomyza control programs in Indonesia that conserve parasitoids, whereas dimehypo and abamectin need to be used cautiously. Local Australian parasitoids should help control L. huidobrensis as long as only cyromazine and nontoxic fungicides are applied.

Body odors of parasitized caterpillars give away the presence of parasitoid larvae to their primary hyperparasitoid enemies.

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Zhu, Feng; Weldegergis, Berhane T; Lhie, Boris; Harvey, Jeffrey A; Dicke, Marcel; Poelman, Erik H

2014-09-01

Foraging success of parasitoids depends on the utilization of reliable information on the presence of their often, inconspicuous hosts. These parasitic wasps use herbivore-induced plant volatiles (HIPVs) that provide reliable cues on host presence. However, host searching of hyperparasitoids, a group of parasitoids that parasitize the larvae and pupae of other parasitoids, is more constrained. Their hosts do not feed on plants, and often are even concealed inside the body of the herbivore host. Hyperparasitoids recently have been found to use HIPVs of plants damaged by herbivore hosts in which the parasitoid larvae develop. However, hyperparasitoids that search for these parasitoid larvae may be confronted with healthy and parasitized caterpillars on the same plant, further complicating their host location. In this study, we addressed whether the primary hyperparasitoid Baryscapus galactopus uses caterpillar body odors to discriminate between unparasitized herbivores and herbivores carrying larvae of parasitoid hosts. We show that the hyperparasitoids made faster first contact and spent a longer mounting time with parasitized caterpillars. Moreover, although the three parasitoid hosts conferred different fitness values for the development of B. galactopus, the hyperparasitoids showed similar behavioral responses to caterpillar hosts carrying different primary parasitoid hosts. In addition, a two-chamber olfactometer assay revealed that volatiles emitted by parasitized caterpillars were more attractive to the hyperparasitoids than those emitted by unparasitized caterpillars. Analysis of volatiles revealed that body odors of parasitized caterpillars differ from unparasitized caterpillars, allowing the hyperparasitoids to detect their parasitoid host.

Defensive behaviors of the Oriental armyworm Mythimna separata in response to different parasitoid species (Hymenoptera: Braconidae).

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Zhou, Jincheng; Meng, Ling; Li, Baoping

2017-01-01

This study examined defensive behaviors of Mythimna separata (Lepidoptera: Noctuidae) larvae varying in body size in response to two parasitoids varying in oviposition behavior; Microplitis mediator females sting the host with the ovipositor after climbing onto it while Meteorus pulchricornis females make the sting by standing at a close distance from the host. Mythimna separata larvae exhibited evasive (escaping and dropping) and aggressive (thrashing) behaviors to defend themselves against parasitoids M. mediator and M. pulchricornis . Escaping and dropping did not change in probability with host body size or parasitoid species. Thrashing did not vary in frequency with host body size, yet performed more frequently in response to M. mediator than to M. pulchricornis . Parasitoid handling time and stinging likelihood varied depending not only on host body size but also on parasitoid species. Parasitoid handling time increased with host thrashing frequency, similar in slope for both parasitoids yet on a higher intercept for M. mediator than for M. pulchricornis . Handling time decreased with host size for M. pulchricornis but not for M. mediator . The likelihood of realizing an ovipositor sting decreased with thrashing frequency of both small and large hosts for M. pulchricornis , while this was true only for large hosts for M. mediator . Our results suggest that the thrashing behavior of M. separata larvae has a defensive effect on parasitism, depending on host body size and parasitoid species with different oviposition behaviors.

Defensive behaviors of the Oriental armyworm Mythimna separata in response to different parasitoid species (Hymenoptera: Braconidae

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Jincheng Zhou

2017-08-01

Full Text Available This study examined defensive behaviors of Mythimna separata (Lepidoptera: Noctuidae larvae varying in body size in response to two parasitoids varying in oviposition behavior; Microplitis mediator females sting the host with the ovipositor after climbing onto it while Meteorus pulchricornis females make the sting by standing at a close distance from the host. Mythimna separata larvae exhibited evasive (escaping and dropping and aggressive (thrashing behaviors to defend themselves against parasitoids M. mediator and M. pulchricornis. Escaping and dropping did not change in probability with host body size or parasitoid species. Thrashing did not vary in frequency with host body size, yet performed more frequently in response to M. mediator than to M. pulchricornis. Parasitoid handling time and stinging likelihood varied depending not only on host body size but also on parasitoid species. Parasitoid handling time increased with host thrashing frequency, similar in slope for both parasitoids yet on a higher intercept for M. mediator than for M. pulchricornis. Handling time decreased with host size for M. pulchricornis but not for M. mediator. The likelihood of realizing an ovipositor sting decreased with thrashing frequency of both small and large hosts for M. pulchricornis, while this was true only for large hosts for M. mediator. Our results suggest that the thrashing behavior of M. separata larvae has a defensive effect on parasitism, depending on host body size and parasitoid species with different oviposition behaviors.

Trade-Off Between Fitness Gain and Cost Determines Profitability of a Peach Aphid Parasitoid.

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Khatri, Diwas; He, Xiong Z; Wang, Qiao

2016-08-01

Aphidius colemani (Viereck) (Hymenoptera: Aphidiidae) is commercially produced and utilized for biological control of peach aphid Myzus persicae (Sulzer) (Hemiptera: Aphididae) on greenhouse crops in many countries. To provide knowledge for the evaluation of parasitoid-host interactions and development of effective mass rearing programs, we investigated how and why host age or size affected fitness gain in A. colemani We show that the parasitoid was significantly more likely to encounter larger hosts and that an encounter almost always triggered an attack attempt. However, the attack attempt did not proportionally translate into oviposition because larger aphids had greater ability to defend themselves and the parasitoid spent more time in handling larger aphids. The host age at parasitization had no effect on emergence rates and sex ratio of parasitoid progeny, suggesting that pupae and larvae have similar survival rate in hosts of different ages and/or the parasitoid females do not adjust sex allocation based on host size. When parasitizing mid-aged hosts, the parasitoid gained maximum fitness for their progeny in developmental period, body size, and parasitism. Taking all findings together, we suggest that parasitizing mid-aged green peach aphid nymphs is most profitable for A. colemani. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Trophic assimilation efficiency markedly increases at higher trophic levels in four-level host-parasitoid food chain.

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Sanders, Dirk; Moser, Andrea; Newton, Jason; van Veen, F J Frank

2016-03-16

Trophic assimilation efficiency (conversion of resource biomass into consumer biomass) is thought to be a limiting factor for food chain length in natural communities. In host-parasitoid systems, which account for the majority of terrestrial consumer interactions, a high trophic assimilation efficiency may be expected at higher trophic levels because of the close match of resource composition of host tissue and the consumer's resource requirements, which would allow for longer food chains. We measured efficiency of biomass transfer along an aphid-primary-secondary-tertiary parasitoid food chain and used stable isotope analysis to confirm trophic levels. We show high efficiency in biomass transfer along the food chain. From the third to the fourth trophic level, the proportion of host biomass transferred was 45%, 65% and 73%, respectively, for three secondary parasitoid species. For two parasitoid species that can act at the fourth and fifth trophic levels, we show markedly increased trophic assimilation efficiencies at the higher trophic level, which increased from 45 to 63% and 73 to 93%, respectively. In common with other food chains, δ(15)N increased with trophic level, with trophic discrimination factors (Δ(15)N) 1.34 and 1.49‰ from primary parasitoids to endoparasitic and ectoparasitic secondary parasitoids, respectively, and 0.78‰ from secondary to tertiary parasitoids. Owing to the extraordinarily high efficiency of hyperparasitoids, cryptic higher trophic levels may exist in host-parasitoid communities, which could alter our understanding of the dynamics and drivers of community structure of these important systems. © 2016 The Authors.

Pengaruh lama ketiadaan inang terhadap kapasitas reproduksi parasitoid Snellenius manilae Ashmead (Hymenoptera: Braconidae

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Mohamad Eldiary Akbar

2015-09-01

Full Text Available The objective of this research was to study the  influence  of host deprivation on the oviposition and physiological condition of Snellenius manilae Ashmead. The research was conducted at Laboratory of Bioecology of Parasitoid and Predator, Department of Plant Protection, Faculty of Agriculture, IPB. Ten parasitoids of the same age and cohort were used in this experiment. Deprivation of hosts were done for 1, 2, 3, 4, 5, 6 and 7 days at the beginning and toward the end of their life. All hosts were replaced every 24 hours. Result indicated that host deprivation affects the reproductive capacity of Snellenius manilae. Even though parasitoids were able to lay eggs even when they were deprived of hosts for seven consecutive days, the overall results of host deprivation experiment showed that the length and timing of deprivation period can affect reproductive capacity. Deprivation of hosts tends to increase the parasitism rate and the numbers of eggs laid upon their first encounter of hosts after the treatment. The difference is more pronounced on treatements that allowed parasitism to occur before the deprivation treatment. However, the overall results suggests that deprivation overall decrease the reproductive capacity of the parasitoid. The longevity of deprived individuals was also lengthened. Parasitoids that were given host before deprivation treatments tend to produced more eggs than those were not. These results showed that deprivation of hosts in the field may affect the effectiveness of parasitoids and the success of biological control.

Host switching in a generalist parasitoid: contrasting transient and transgenerational costs associated with novel and original host species.

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Jones, Thomas S; Bilton, Adam R; Mak, Lorraine; Sait, Steven M

2015-01-01

Parasitoids face challenges by switching between host species that influence survival and fitness, determine their role in structuring communities, influence species invasions, and affect their importance as biocontrol agents. In the generalist parasitoid, Venturia canescens (Gravenhorst) (Hymenoptera: Ichneumonidae), we investigated the costs in encapsulation, survival, and body size on juveniles when adult parasitoids switched from their original host, Plodia interpunctella (Hübner) (Lepidotera, Pyralidae) to a novel host, Ephestia kuehniella (Zeller) (Lepidoptera, Pyralidae), over multiple generations. Switching had an initial survival cost for juvenile parasitoids in the novel host, but increased survival occurred within two generations. Conversely, mortality in the original host increased. Body size, a proxy for fecundity, also increased with the number of generations in the novel host species, reflecting adaptation or maternal effects due to the larger size of the novel host, and therefore greater resources available to the developing parasitoid. Switching to a novel host appears to have initial costs for a parasitoid, even when the novel host may be better quality, but the costs rapidly diminish. We predict that the net cost of switching to a novel host for parasitoids will be complex and will depend on the initial reduction in fitness from parasitizing a novel host versus local adaptations against parasitoids in the original host.

Infection of army ant pupae by two new parasitoid mites (Mesostigmata: Uropodina

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Adrian Brückner

2017-10-01

Full Text Available A great variety of parasites and parasitoids exploit ant societies. Among them are the Mesostigmata mites, a particularly common and diverse group of ant-associated arthropods. While parasitism is ubiquitous in Mesostigmata, parasitoidism has only been described in the genus Macrodinychus. Yet information about the basic biology of most Macrodinychus species is lacking. Out of 24 formally described species, information about basic life-history traits is only available for three species. Here we formally describe two new Macrodinychus species, i.e. Macrodinychus hilpertae and Macrodinychus derbyensis. In both species, immature stages developed as ecto-parasitoids on ant pupae of the South-East Asian army ant Leptogenys distinguenda. By piercing the developing ant with their chelicera, the mites apparently suck ant hemolymph, ultimately killing host individuals. We compare infection rates among all studied Macrodinychus species and discuss possible host countermeasures against parasitoidism. The cryptic lifestyle of living inside ant nests has certainly hampered the scientific discovery of Macrodinychus mites and we expect that many more macrodinychid species await scientific discovery and description.

Infection of army ant pupae by two new parasitoid mites (Mesostigmata: Uropodina).

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Brückner, Adrian; Klompen, Hans; Bruce, Andrew Iain; Hashim, Rosli; von Beeren, Christoph

2017-01-01

A great variety of parasites and parasitoids exploit ant societies. Among them are the Mesostigmata mites, a particularly common and diverse group of ant-associated arthropods. While parasitism is ubiquitous in Mesostigmata, parasitoidism has only been described in the genus Macrodinychus . Yet information about the basic biology of most Macrodinychus species is lacking. Out of 24 formally described species, information about basic life-history traits is only available for three species. Here we formally describe two new Macrodinychus species, i.e. Macrodinychus hilpertae and Macrodinychus derbyensis . In both species, immature stages developed as ecto-parasitoids on ant pupae of the South-East Asian army ant Leptogenys distinguenda . By piercing the developing ant with their chelicera, the mites apparently suck ant hemolymph, ultimately killing host individuals. We compare infection rates among all studied Macrodinychus species and discuss possible host countermeasures against parasitoidism. The cryptic lifestyle of living inside ant nests has certainly hampered the scientific discovery of Macrodinychus mites and we expect that many more macrodinychid species await scientific discovery and description.

Hymenopteran parasitoids associated with frugivorous larvae in a Brazilian caatinga-cerrado ecotone.

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De Souza, A R; Lopes-Mielezrski, G N; Lopes, E N; Querino, R B; Corsato, C D A; Giustolin, T A; Zucchi, R A

2012-04-01

The purpose of this study was to investigate native species of parasitoids of frugivorous larvae and their associations with host plants in commercial guava orchards and in typical native dry forests of a caatinga-cerrado ecotone in the State of Minas Gerais, Brazil. Nine species of parasitoids were associated with larvae of Anastrepha (Tephritidae) and Neosilba (Lonchaeidae) in fruit of Psidium guajava L. (Myrtaceae), Ziziphus joazeiro Mart. (Rhamnaceae), Spondias tuberosa Arruda (Anacardiaceae), Spondias dulcis Forst. (Anacardiaceae), Syzygium cumini (L.) Skeels (Myrtaceae), and Randia armata (Sw.) DC. (Rubiaceae). Doryctobracon areolatus was the most abundant species, obtained from puparia of Anastrepha zenildae, An. sororcula, An. fraterculus, An. obliqua, and An. turpiniae. This is the first report of Asobara obliqua in Brazil and of As. anastrephae and Tropideucoila weldi in dry forests of Minas Gerais State. The number of species of parasitoids was higher in areas with greater diversity of cultivated species and lower pesticide use. The forest fragments adjacent to the orchards served as shelter for parasitoids of frugivorous larvae.

First records of parasitoids attacking the Asian citrus psyllid in Ecuador

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Diego E. Portalanza

Full Text Available ABSTRACT First records of parasitoids attacking the Asian citrus psyllid in Ecuador. The objective of the current study was to investigate the presence of natural enemies of Diaphorina citri (Hemiptera: Liviidae (the Asian citrus psyllid in Ecuador. Incidence of parasitoid Diaphorencyrtus aligarhensis (Hymenoptera: Encyrtidae was assessed between November 2015 and March 2016, in Letamendi, Febres-Cordero and Tarqui, urban districts of Guayaquil. Highest incidence of parasitism occurred in those regions and seasons of the year with the highest temperatures commensurate with increase of citrus plant shoots. Similar to their host, these parasitoids appear to have established in Ecuador by accident, and were not the result of purposeful introduction. This fortuitous introduction is a potentially helpful tool in controlling the Asian citrus psyllid, and potentially Huanglongbing.

Interactions to the fifth trophic level: secondary and tertiary parasitoid wasps show extraordinary efficiency in utilizing host resources

NARCIS (Netherlands)

Harvey, J.A.; Wagenaar, R.; Bezemer, T.M.

2009-01-01

1. Parasitoid wasps are highly efficient organisms at utilizing and assimilating limited resources from their hosts. This study explores interactions over three trophic levels, from the third (primary parasitoid) to the fourth (secondary parasitoid) and terminating in the fifth (tertiary

Predators and parasitoids of Cacopsylla pyri (L.) (Hemiptera: Psyllidae) in Serbia

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Jerinić-Prodanović Dušanka; Protić Ljiljana; Mihajlović Ljubodrag

2010-01-01

The presence of C. pyri and its natural enemies was studied in both treated and untreated pear orchards in Serbia from 2005 to 2009. Five parasitoid and 21 predator species were identified as present on a considerable number of sites. The following parasitoid species were found: Prionomitus mitratus (Dalman), Psyllaephagus procerus Marcet, Syrphophagus ariantes (Walker), Syrphophagus taeniatus (Forster) and Tamarixia sp. In the study, the species Psyllaephagus procerus, Syrphophagus ariantes ...

The parasitoids of the asparagus miner (Diptera: Agromyzidae): field parasitism and the influence of food resources on life history.

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Morrison, William R; Gibson, Gary A P; Szendrei, Zsofia

2014-12-01

The goals of this study were to identify pupal parasitoids of the asparagus miner, Ophiomyia simplex Loew (Diptera: Agromyzidae), and examine the effect of different diets and floral resources on the lifespan of adult asparagus miners and their parasitoids. We also measured the effect of parasitism on stem damage caused by the asparagus miner. The identity and abundance of the parasitoids of the asparagus miner were determined in asparagus fields in Michigan from weekly asparagus miner pupal collections during the 2010-2013 seasons. Twelve species of hymenopterous parasitoids were reared from asparagus miner pupae, including Chorebus rondanii (Giard) (Ichneumonoidea: Braconidae), 10 species in three families of Chalcidoidea, and one species of Bethylidae (Chrysidoidea), that represent new host records for the asparagus miner. C. rondanii and Thinodytes cephalon (Walker) (Pteromalidae) were the most common parasitoids. The effects of different diets and flowers on the lifespan of the pest and parasitoid adults were also evaluated. Buckwheat resulted in the shortest life span for the asparagus miner, whereas Riddell's goldenrod significantly increased its lifespan relative to the control. Parasitoid lifespan was doubled when individuals were fed sugar-rich diets. In the field, parasitoids preferred stems that contained more pupae and damage. The two most commonly reared parasitoids should be considered as targets for future conservation biological control efforts of the asparagus miner.

Impact of water-deficit stress on tritrophic interactions in a wheat-aphid-parasitoid system.

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Syed Suhail Ahmed

Full Text Available Increasing temperature and CO2 concentrations can alter tritrophic interactions in ecosystems, but the impact of increasingly severe drought on such interactions is not well understood. We examined the response of a wheat-aphid-parasitoid system to variation in water-deficit stress levels. Our results showed that arid area clones of the aphid, Sitobion avenae (Fabricius, tended to have longer developmental times compared to semiarid and moist area clones, and the development of S. avenae clones tended to be slower with increasing levels of water-deficit. Body sizes of S. avenae clones from all areas decreased with increasing water-deficit levels, indicating their declining adaptation potential under drought. Compared to arid area clones, moist area clones of S. avenae had a higher frequency of backing under severe water stress only, but a higher frequency of kicking under well-watered conditions only, suggesting a water-deficit level dependent pattern of resistance against the parasitoid, Aphidius gifuensis (Ashmead. The number of S. avenae individuals attacked by the parasitoid in 10 min showed a tendency to decrease with increasing water-deficit levels. Clones of S. avenae tended to have lower parasitism rates under treatments with higher water-deficit levels. The development of the parasitoid tended to be slower under higher levels of water-deficit stress. Thus, the bottom-up effects of water-deficit stressed plants were negative on S. avenae. However, the top-down effects via parasitoids were compromised by water-deficit, which could favor the growth of aphid populations. Overall, the first trophic level under water-deficit stress was shown to have an indirect and negative impact on the third trophic level parasitoid, suggesting that parasitoids could be increasingly vulnerable in future warming scenarios.

Population Dynamics of Native Parasitoids Associated with the Asian Chestnut Gall Wasp (Dryocosmus kuriphilus in Italy

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Tiziana Panzavolta

2018-01-01

Full Text Available Native parasitoids may play an important role in biological control. They may either support or hinder the effectiveness of introduced nonnative parasitoids released for pest control purposes. Results of a three-year survey (2011–2013 of the Asian chestnut gall wasp (ACGW Dryocosmus kuriphilus Yasumatsu (Hymenoptera: Cynipidae populations and on parasitism rates by native indigenous parasitoids (a complex of chalcidoid hymenopterans in Italian chestnut forests are given. Changes in D. kuriphilus gall size and phenology were observed through the three years of study. A total of 13 species of native parasitoids were recorded, accounting for fluctuating parasitism rates. This variability in parasitism rates over the three years was mainly due to the effect of Torymus flavipes (Walker (Hymenoptera: Torymidae, which in 2011 accounted for 75% of all parasitoid specimens yet decreased drastically in the following years. This strong fluctuation may be related to climatic conditions. Besides, our data verified that parasitoids do not choose host galls based on their size, though when they do parasitize smaller ones, they exploit them better. Consequently, ACGWs have higher chances of surviving parasitism if they are inside larger galls.

Conservation of Agroecosystem through Utilization of Parasitoid Diversity: Lesson for Promoting Sustainable Agriculture and Ecosystem Health

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DAMAYANTI BUCHORI

2008-12-01

Full Text Available For many years, agricultural intensification and exploitation has resulted in biodiversity loss and threaten ecosystem functioning. Developing strategies to bridge human needs and ecosystem health for harmonization of ecosystem is a major concern for ecologist and agriculturist. The lack of information on species diversity of natural enemies and how to utilize them with integration of habitat management that can renovate ecological process was the main obstacle. Parasitoids, a group of natural enemies, play a very important role in regulating insect pest population. During the last ten years, we have been working on exploration of parasitoid species richness, how to use it to restore ecosystem functions, and identifying key factors influencing host-parasitoid interaction. Here, we propose a model of habitat management that is capable of maintaining agricultural biodiversity and ecosystem functions. We present data on parasitoid species richness and distribution in Java and Sumatera, their population structure and its impact toward biological control, relationship between habitat complexes and parasitoid community, spatial and temporal dynamic of parasitoid diversity, and food web in agricultural landscape. Implications of our findings toward conservation of agroecosystem are discussed.

Best Host Age of Anastrepha obliqua (Diptera: Tephritidae) for Multiplication of Four Native Parasitoids from the Americas

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Poncio, S; Montoya, P; Cancino, J; Nava, D E

2018-01-01

Abstract The success of the mass rearing of parasitoids is directly related to host quality, and it requires selecting the best biological host age to ensure the optimal performance of the parasitoids released into the field. The larval development of the parasitoids Utetes anastrephae (Viereck) (Hymenoptera: Braconidae) and Odontosema anastrephae Borgmeier (Hymenoptera: Eucoilidae) and the pupal development of the parasitoids Coptera haywardi (Ogloblin) (Hymenoptera: Diapriidae) and Dirhinus sp. (Hymenoptera: Chalcididae) on the native host Anastrepha obliqua (Macquart) (Diptera: Tephritidae) in different larvae and pupae ages were investigated under laboratory conditions. Not all parasitoid species developed with the same efficiency in immature individuals of A. obliqua; U. anastrephae and C. haywardi showed the higher parasitism rates. The emergence and parasitism of U. anastrephae were equal using larvae from 5 to 8 d, while C. haywardi reared in 1- to 8-d-old pupae showed higher averages of parasitism. These results suggest that native parasitoids can be used to strengthen the implementation of biological control projects against A. obliqua, a pest of economic importance in South America.

Effects of environmental parameters on the chestnut gall wasp and its complex of indigenous parasitoids

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Bonsignore, Carmelo Peter; Bernardo, Umberto

2018-04-01

The chestnut gall wasp (CGW), Dryocosmus kuriphilus, an invasive pest native to China, has caused severe yield and economic losses to chestnut production in Europe since its arrival in 2002. In Southern Italy, the complex of indigenous parasitoids colonizing CGW was monitored between 2013 and 2015, with the aim of estimating the composition of the indigenous parasitoid complex, its ability to control CGW populations, and the interactions of both factors with several measured environmental parameters. We compared results among three differently managed field types. Results showed an increase in the rate of parasitism both when the host population density was lower and in unmanaged chestnut stands with more natural conditions. The percentage of parasitism in galls was related to morphological traits of the galls and to higher seasonal temperatures, which reduced the parasitism intensity because CGW develops earlier under such conditions. The host-parasitoid mortality inside galls varied among sites and was associated mostly with rot fungi during wet spring and summer months. Parasitoid species richness was similar among the study sites, but the proportion of parasitoid species differed between orchards and unmanaged coppice stands. The timing of attack by parasitoids followed a species-specific successional sequence throughout the larva-to-adult life cycle of the CGW. These interactions should be considered in future research on trophic relationships and when modeling invasive scenarios for new pest species.

Lepidopterans and their parasitoids on okra plants in Riberão Preto (SP, Brazil Lepidópteros e seus parasitoides em cultura de quiabo em Ribeirão Preto, SP, Brasil

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Rogéria Inês Rosa Lara

2012-04-01

Full Text Available The aim of this study was to identify the defoliating lepidopterans and their parasitoids occurring on okra plants in the district of Riberão Preto city (SP. Brazil. Caterpillars were collected by hand from an experimental field of okra, in March and April, 2009. They were placed individually on Petri dishes lined with wet filter paper, containing shredded okra leaves, and kept in a climactic chamber (25±1°C, 12:12h light/dark photoperiod, RH 70±10% until the emergence of lepidopterans and/or parasitoids. In all, 63 lepidopterans were obtained: three species of Noctuidae, Anomis flava (Fabricius, Spodoptera frugiperda (Smith and Pseudoplusia includens (Walker; one of Pieridae, Ascia monuste orseis (Godart, and an unidentified species of Tortricidae. One unidentified tachinid fly (Diptera and the Hymenoptera parasitoids Copidosoma floridanum (Ashmead (Encyrtidae and Euplectrus sp. (Eulophidae emerged from A. flava, while C. floridanum and an unidentified tachinid, from P. includens. This is the first report of an association between the herbivores S. frugiperda, P. includens and A. monuste orceis, the parasitoids C. floridanum and Euplectrus sp. on okra plants.Este estudo objetivou identificar lepidópteros desfolhadores e seus parasitoides em cultura de quiabo em Ribeirão Preto, SP, Brasil. As lagartas foram coletadas através de catação manual entre março e abril de 2009, individualizadas em placas de Petri forradas com papel filtro umedecido contendo pedaços de folhas de quiabo e mantidas sob condições controladas (25±1°C, 12 horas de fotofase, 70±10% de UR até a obtenção dos adultos de lepidópteros e/ou de seus parasitoides. Foram obtidos 63 adultos de lepidópteros: três espécies de Noctuidae, Anomis flava (Fabricius, Spodoptera frugiperda (Smith, Pseudoplusia includens (Walker, uma de Pieridae, Ascia monuste orseis (Godart e uma de Tortricidae não identificada. Uma espécie não identificada de taquinídeo (Diptera e os

Host habitat assessment by a parasitoid using fungal volatiles

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Steidle Johannes LM

2007-02-01

Full Text Available Abstract Background The preference – performance hypothesis predicts that oviposition preference of insects should correlate with host suitability for offspring development. Therefore, insect females have to be able to assess not only the quality of a given host but also the environmental conditions of the respective host habitat. Chemical cues are a major source of information used by insects for this purpose. Primary infestation of stored grain by stored product pests often favors the intense growth of mold. This can lead to distinct sites of extreme environmental conditions (hot-spots with increased insect mortality. We studied the influence of mold on chemical orientation, host recognition, and fitness of Lariophagus distinguendus, a parasitoid of beetle larvae developing in stored grain. Results Volatiles of wheat infested by Aspergillus sydowii and A. versicolor repelled female parasitoids in an olfactometer. Foraging L. distinguendus females are known to be strongly attracted to the odor of larval host feces from the granary weevil Sitophilus granarius, which may adhere in remarkable amounts to the surface of the grains. Feces from moldy weevil cultures elicited neutral responses but parasitoids clearly avoided moldy feces when non-moldy feces were offered simultaneously. The common fungal volatile 1-octen-3-ol was the major component of the odor of larval feces from moldy weevil cultures and repelled female parasitoids at naturally occurring doses. In bioassays investigating host recognition behavior of L. distinguendus, females spent less time on grains containing hosts from moldy weevil cultures and showed less drumming and drilling behavior than on non-moldy controls. L. distinguendus had a clearly reduced fitness on hosts from moldy weevil cultures. Conclusion We conclude that L. distinguendus females use 1-octen-3-ol for host habitat assessment to avoid negative fitness consequences due to secondary mold infestation of host

Changes in host-parasitoid food web structure with elevation.

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Maunsell, Sarah C; Kitching, Roger L; Burwell, Chris J; Morris, Rebecca J

2015-03-01

Gradients in elevation are increasingly used to investigate how species respond to changes in local climatic conditions. Whilst many studies have shown elevational patterns in species richness and turnover, little is known about how food web structure is affected by elevation. Contrasting responses of predator and prey species to elevation may lead to changes in food web structure. We investigated how the quantitative structure of a herbivore-parasitoid food web changes with elevation in an Australian subtropical rain forest. On four occasions, spread over 1 year, we hand-collected leaf miners at twelve sites, along three elevational gradients (between 493 m and 1159 m a.s.l). A total of 5030 insects, including 603 parasitoids, were reared, and summary food webs were created for each site. We also carried out a replicated manipulative experiment by translocating an abundant leaf-mining weevil Platynotocis sp., which largely escaped parasitism at high elevations (≥ 900 m a.s.l.), to lower, warmer elevations, to test if it would experience higher parasitism pressure. We found strong evidence that the environmental change that occurs with increasing elevation affects food web structure. Quantitative measures of generality, vulnerability and interaction evenness decreased significantly with increasing elevation (and decreasing temperature), whilst elevation did not have a significant effect on connectance. Mined plant composition also had a significant effect on generality and vulnerability, but not on interaction evenness. Several relatively abundant species of leaf miner appeared to escape parasitism at higher elevations, but contrary to our prediction, Platynotocis sp. did not experience greater levels of parasitism when translocated to lower elevations. Our study indicates that leaf-mining herbivores and their parasitoids respond differently to environmental conditions imposed by elevation, thus producing structural changes in their food webs. Increasing

Side-Effects of Glyphosate to the Parasitoid Telenomus remus Nixon (Hymenoptera: Platygastridae).

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Stecca, C S; Bueno, A F; Pasini, A; Silva, D M; Andrade, K; Filho, D M Z

2016-04-01

The aim of this study was to compare the side-effects of glyphosate to the parasitoid Telenomus remus Nixon (Hymenoptera: Platygastridae) when parasitoids were exposed to this chemical at the pupal (inside host eggs) and adult stages. Bioassays were conducted under laboratory conditions according to the International Organization for Biological Control (IOBC) standard methods for testing side-effects of pesticides to egg parasitoids. Different glyphosate-based pesticides (Roundup Original®, Roundup Ready®, Roundup Transorb®, Roundup WG®, and Zapp Qi®) were tested at the same acid equivalent concentration. Treatments were classified following the IOBC toxicity categories as (1) harmless, (2) slightly harmful, (3) moderately harmful, and (4) harmful. When tested against T. remus adults, Roundup Original®, Roundup Ready®, Roundup Transorb®, and Roundup WG® reduced parasitism 2 days after parasitoid emergence, being classified as slightly harmful. Differently, when tested against T. remus pupae, all tested glyphosate-based products did not differ in their lethal effect and therefore did not reduce T. remus adult emergence or parasitism capacity, being classified as harmless. However, differences on sublethal toxicity were found. Parasitism of individuals emerging from parasitized eggs sprayed at the pupal stage of T. remus with Zapp Qi® was lower compared to control, but parasitism was still higher than 66%, and therefore, Zapp Qi® was still classified as harmless. In conclusion, all tested glyphosate-based products can be used in agriculture without negative impact to T. remus as none was classified as harmful or moderately harmful to this parasitoid when exposure occurred at the pupal or adult stages.

Different approaches to labelling parasitoids using strontium

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Gu, H.; Wäckers, F.L.; Steindl, P.; Günther, D.; Dorn, S.

2001-01-01

Labelling parasitoids with trace elements is a potentially powerful technique for studying dispersal and trophic interactions in these usually small insects. Laboratory experiments were conducted to investigate the feasibility and efficiency of different methods for trace element labelling of the

Utilisation of the egg-larval parasitoid, Fopius (Biosteres) arisanus, for augmentative biological control of tephritid fruit flies

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Harris, Ernest J.; Bautista, Renato C.; Spencer, John P.

2000-01-01

In Hawaii, entomologists concerned about tephritid fruit fly control recognise and accept the fact that the introduction of tephritid fruit flies consisting of the melon fly Bactrocera cucurbitae (Coquillet), Mediterranean fruit fly, C. capitata (Wiedemann), Oriental fruit fly, B. dorsalis (Hendel) and the Solanaceous fruit fly, B. latifrons (Hendel) required the introduction of many species of parasitoids into Hawaii (Clausen 1956) to reduce crop damage caused by tephritid fruit flies. The parasitoids established in the order of their succession were Diachasimorpha longicaudata (Ashmead), Biosteres vandenboschi (Fullaway), and Fopius (Biosteres) arisanus (Sonan). F. arisanus was first discovered in Hawaii in 1949 in a guava fruit collection (van den Bosch and Haramoto 1951). In 1950, the rate of parasitism caused F. arisanus to increase and this insect spread and became the dominant and most widely distributed parasitoid in Hawaii (Haramoto and Bess 1970). Entomologists investigating fruit fly ecology in Hawaii recognised that the four species of tephritid fruit flies differ in their distribution, abundance and host utilisation patterns in different habitats. The rapid spread and distribution of F. arisanus in Hawaii indicated the reality that among the parasitoids, F. arisanus has the highest adaptation capabilities in the Hawaiian ecosystem comparable to that of B. dorsalis and C. capitata, the most persistent fruit fly species in Hawaii. A strategy receiving high priority to improve biological control of tephritid fruit flies is foreign exploration to find new parasitoids for introduction into tephritid fruit fly invested areas including Guatemala and Hawaii. It is possible another species comparable to F. arisanus might be found. New introductions could increase the diversity of parasitoid species and result in the introduction of species more efficient for suppressing B. latifrons in Hawaii. The cost of parasitoid exploration is very expensive, US$100,000 or

Inter and intra-guild interactions in egg parasitoid species of the soybean stink bug complex

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Sujii Edison Ryoiti

2002-01-01

Full Text Available The objective of this research was to evaluate the parasitism behavior of Telenomus podisi Ashmead, Trissolcus basalis (Wollaston e Trissolcus urichi Crawford (Hymenoptera: Scelionidae on eggs of Nezara viridula L., Euschistus heros F., Piezodorus guildinii Westwood and Acrosternum aseadum Rolston (Heteroptera: Pentatomidae, in no choice and multiple choice experiments. For all parasitoid species, the results demonstrated the existence of a main host species that maximizes the reproductive success. The competitive interactions among the parasitoid species were investigated in experiments of sequential and simultaneous release of different combinations of parasitoid pairs on the hosts N. viridula, E. heros and A. aseadum. Exploitative competition was observed for egg batches at the genus level (Telenomus vs. Trissolcus and interference competition at the species level (T. basalis vs. T. urichi. Trissolcus urichi was the most aggressive species, interfering with the parasitism of T. basalis. Generally, T. basalis showed an opportunistic behavior trying to parasitise eggs after T. urichi had abandoned the egg batch. The selection of parasitoid species for use in augmentative biological control programs should take into account the diversity of pentatomids present in soybean in addition to the interactions among the different species of parasitoids.

Effect of the parasitoid Diaeretiella rapae on the feeding rate of its host Brevicoryne brassicae

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Couchman, J.R.; King, P.E.

1979-01-01

The food uptake by Brevicoryne brassicae, as measured by accumulation of radiophosphorus, is influenced by the presence of developing larvae of the parasitoid Diaeretiella rapae. Though the egg and embryonic stages of the parasitoid have no effect on host feeding the presence of a first-instar larva lowers the food uptake. Feeding returns to a level similar to that of non-parasitised aphids when a second-instar parasitoid is present within a host, but drops again when the third instar is reached. Host death occurs during the fourth-larval instar. (Auth.)

Effect of Different Diets of Flour Moth on its Parasitoid Wasp Fitness, Trichogramma brassicae (Hym.:Trichogrammatidae

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Paria Soltaninejad

2017-03-01

Full Text Available Introduction: Parasitoid wasp, Trichogramma brassicae (Bezdenko (Hym.: Trichogrammatidae has excellent position in mass production technology, scope of application, wide geographical distribution and unmatched talent to adapt to different climatic conditions that can be easily reared on Mediterranean flour moth (MFM, Ephestia kuehniella Zeller (Lep.: Pyralidae. The parasitoid use is in order to control Chilo suppressalis (Walker (Lep.: Pyralidae, Helicoverpa armigera (Lep.: Noctuidae, Ostrinia nubilalis (Hübner (Lep.: Pyralidae, Ectomyelois ceratoniae (Zeller (Lep.: Phycitidae and Cydia pomonella (Lep.: Tortricidae (38. The studies have been shown that the quantity and quality of the host diet affect growth period, size of adults, adult longevity, fecundity and sex ratio of the parasitoid. The objective of current research was to evaluate the effect of four different MFM diets on the fitness of second and forth generations of the parasitoid wasp, T. brassicae. Materials and Methods: The four diets ((I wheat flour, wheat bran, corn flour, bread yeast and glycerin; (II wheat flour, wheat bran, barley flour, bread yeast and glycerin; (III barley flour, bread yeast and glycerin and (IV wheat flour, barley flour and corn flour were sterilized at 51 °C for 24 hours. After cooling at ambient temperature, the diets were contaminated with the eggs of MFM and then were maintained at 25±1° C, 60±5 % RH and a photoperiod of 14 L: 10 D. The MFM adults emerged after 35 to 40 days and their eggs were collected daily to use for investigation of the parasitoid biology. For rearing the parasitoid wasps on the MFM eggs obtained from each diet, some cards containing the parasitoid pre-pupae were put inside cages (25 × 25 × 25 cm and reared for one generation. The adults were fed honey (20% for one day and then were provided with one-day-old sterile MFM eggs. To prevent egg hatching and sterile them, they were kept at 15°C for four h. The tests were

Host feeding in insect parasitoids: why destructively feed upon a host that excretes an alternative?

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Burger, J.S.M.; Reijnen, T.M.; Van Lenteren, J.C.; Vet, L.E.M.

2004-01-01

Host feeding is the consumption of host tissue by the adult female parasitoid. We studied the function of destructive host feeding and its advantage over non-destructive feeding on host-derived honeydew in the whitefly parasitoid Encarsia formosa Gahan (Hymenoptera: Aphelinidae). We allowed

Pengaruh insektisida deltametrin terhadap perilaku orientasi parasitoid Anagrus nilaparvatae (Pang et Wang (Hymenoptera: Mymaridae

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Araz Meilin

2016-09-01

Full Text Available Host searching behaviour by a parasitoid includes orientation to the volatile compounds (odor relesead by host or host plant. The aim of this study was to determine the changes in the orientation behaviour of Anagrus nilaparvatae (Pang et Wang, the egg parasitoid of rice brown planthoppers (Nilaparvata lugens (Stål, after being exposed to sublethal concentrations of deltamethrin. The impact of residue on plants to the behaviour of parasitoid was also studied. The sublethal concentrations (LC10 and LC40 used were 0.023 ppm and 2.235 ppm, respectively. Deltamethrin applied to the rice plants were 12.5 ppm and 6.25 ppm, and its effect was observed at 3 hours, 1, 3 and 7 days after application. Orientation behavior was studied using Y-tube olfactometer. Application of deltamethrin at subletal concentration reduced the ability of surviving A. nilaparvatae to detect odors (volatile ompounds released by the host, N. lugens. The higher the concentration of deltamethrin applied to the parasitoid or to the rice plants, the more prominent effect observed in the changing in the parasitoid behavious, in particular disruption to the parasitoid’s orientation to find their host. As consequences, effects of deltamethrin may lead to reduce the effectiveness of A. nilaparvatae as biological control agents in the field as a result of declining their searching capacity. 

Immunity of an alternative host can be overcome by higher densities of its parasitoids Palmistichus elaeisis and Trichospilus diatraeae.

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Gilberto Santos Andrade

Full Text Available Interactions of the parasitoids Palmistichus elaeisis Delvare & LaSalle and Trichospilus diatraeae Cherian & Margabandhu (Hymenoptera: Eulophidae with its alternative host Anticarsia gemmatalis (Hübner (Lepidoptera: Noctuidae affect the success or failure of the mass production of these parasitoids for use in integrated pest management programs. The aim of this study was to evaluate changes in the cellular defense and encapsulation ability of A. gemmatalis pupae against P. elaeisis or T. diatraeae in adult parasitoid densities of 1, 3, 5, 7, 9, 11 or 13 parasitoids/pupae. We evaluated the total quantity of circulating hemocytes and the encapsulation rate versus density. Increasing parasitoid density reduced the total number of hemocytes in the hemolymph and the encapsulation rate by parasitized pupae. Furthermore, densities of P. elaeisis above 5 parasitoids/pupae caused higher reduction in total hemocyte numbers. The encapsulation rate fell with increasing parasitoid density. However, parasitic invasion by both species induced generally similar responses. The reduction in defensive capacity of A. gemmatalis is related to the adjustment of the density of these parasitoids to their development in this host. Thus, the role of the density of P. elaeisis or T. diatraeae by pupa is induced suppression of cellular defense and encapsulation of the host, even without them possesses a co-evolutionary history. Furthermore, these findings can predict the success of P. elaeisis and T. diatraeae in the control of insect pests through the use of immunology as a tool for evaluation of natural enemies.

Age-specific interaction between the parasitoid, Encarsia formosa and its host, the silverleaf whitefly, Bemisia tabaci (Strain B

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Jing S. Hu

2003-08-01

Full Text Available The effect of hostage, the instar of Bemisia tabaci (Gennadius parasitized, on the growth and development of Encarsia formosa (Gahan was studied. E. formosa was able to parasitize and complete its life cycle no matter which instar of B. tabaci (Strain B, [also identified as B. argentifolii (Bellows and Perring], was provided for oviposition, but parasitoid development was significantly slower when 1st or 2nd instar B. tabaci rather than 3rd or 4th instars were parasitized. Host age influenced the day on which E. formosa nymphs hatching from eggs was first observed. Mean embryonic development was significantly longer when 1st (5.4 days rather than 2nd, 3rd or 4th instars (4.1, 3.4 and 3.5 days, respectively were parasitized. The duration of the 1st instar parasitoid and the pupa, but not the 2nd or 3rd instar parasitoid, were also significantly greater when 1st instars were parasitized than when older host instars were parasitized. Interestingly, no matter which instar was parasitized, the parasitoid did not molt to the 3rd instar until the 4th instar host had reached a depth of about 0.23 mm (Stage 4-5 and had initiated the nymphal-adult molt and adult development. Histological studies revealed that whitefly eye and wing structures had either disintegrated or were adult in nature whenever a 3rd instar parasitoid was present. It appears, then, that the molt of the parasitoid to its last instar is associated with the host whitefly's nymphal-adult molt. However, the initiation of the host's final molt, while a prerequisite for the parasitoid's 2nd-3rd instar molt, did not necessarily trigger this molt. In contrast to its significant effect on various aspects of parasitoid development, host instar did not significantly influence the mean size of the parasitoid larva, pupa, or adult. Larval and pupal length and adult head width were similar for all parasitoids, regardless of which host instar was parasitized as was adult longevity. Adult parasitoid

(Brief report Evaluation of Suitable Host Plant, as Banker Plant for Eretmocerus mundus, Whiteflies Parasitoid

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M. J. Ardeh

2016-03-01

Full Text Available Introduction: Whiteflies (Homoptera; Aleyrodidae are the key pests of agricultural crops worldwide. Two species, which seriously damage crops, are the Silver leaf whitefly “Bemisia tabaci (Gennadius” and the Greenhouse whitefly “Trialeorodes vaporariorum (Westwood”. These pests are active on the underside of the leaves where they are relatively protected from insecticide. Moreover, emergence of resistant biotypes of whitelies impose much more costs on its chemical control. Therefore, during falling the past population, several researches have been carried out to find and use efficient biocontrol methods. One of the biocontrol agents to control B. tabaci is “Eretmocerus mundus” (Hy., Aphelinidae. The parasitoid should be introduced to control pest in the greenhouses. One of the methods, which is used in introducing of biological control agents, is ‘Banker Plant System’. In this system, the host plant has a population of reproducing natural enemy used as a reservoir. Therefore, as soon as the pest infection occurs, the parasitoids can find them and control the damage. İn a banker plant system, several aspects should be considered. Some of the behavioral and biological aspects are important. For example characteristics of leaf surface influence on the host finding time of the parasitoid. The biochemical characteristics of the host plants affect the parasitoid fitness. Therefore, we tried to compare these aspects of E. mundus in two host plants (eggplant and cotton from banker plant point of view, to control B. tabaci in the greenhouses. Materials and Methods: The two host plants (eggplant and cotton, were planted in the greenhouse and a culture of B. tabaci was reared on the plants. After two weeks, some of the infested plants were put in separate cages, and the parasitoid, E. mundus, that was collected from the egg plant and cotton fields of the Varamin region were released on the plants. Then, the biological characteristics of

Predators and Parasitoids of Cacopsylla pyri (L. (Hemiptera: Psyllidae in Serbia

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Dušanka Jerinić Prodanović

2010-01-01

Full Text Available The presence of C. pyri and its natural enemies was studied in both treated and untreated pear orchards in Serbia from 2005 to 2009. Five parasitoid and 21 predator species were identified as present on a considerable number of sites. The following parasitoid species were found: Prionomitus mitratus (Dalman,Psyllaephagus procerus Marcet,Syrphophagus ariantes (Walker,Syrphophagus taeniatus Förster and Tamarixia sp. In the study, the species Psyllaephagus procerus,Syrphophagus ariantes and Tamarixia sp. were forthe first time identified as parasitoids of C. pyri and as new species in the Serbian fauna.Among the parasitoids determined, Prionomitus mitratus predominated. Of the predators, the following species in four orders were registered: Dermaptera [Forficula auricularia Linnaeus (Forficulidae], Heteroptera [Anthocoris nemoralis(Fabricius, Anthocoris nemorum (Linnaeus, Orius (Heterorius minutus (Linnaeus, Orius (Heterorius nigerWolff (Anthocoridae, Campylomma verbasci (Mayer-Dür, Deraeocoris (Deraeocorisruber(Linnaeusand Deraeocoris(Knightocarsuslutescens (Schilling(Miridae],Neuroptera[Chrysopa pallens Rambur,Chrysoperla carnea(Stephens,Chrysopa sp.(Chrysopidae], and Coleoptera [Coccinella septempunctata Linnaeus, Adalia bipunctata Linnaeus, Adalia decempunctata(Linnaeus, Hippodamia tredecimpunctata (Linnaeus,Hippodamia variegata(Goeze,Propylea quatuordecimpunctata (Linnaeus, Calvia (Anisocalvia quatuordecimguttata(Linnaeus(Coccinellidae, Cantharis rustica Fallén, Rhagonycha fulva (Scopoli and Rh. testacea(Linnaeus (Cantharidae]. Of the predators determined, 12 species were registered for the first time as predators of C. pyri in Serbia, while C. rustica, Rhagonycha fulva and Rh.testacea have so far been known neither in Serbia nor in the world as predators of pear suckers.

Decision-making dynamics in parasitoids of Drosophila.

Science.gov (United States)

Thiel, Andra; Hoffmeister, Thomas S

2009-01-01

Drosophilids and their associated parasitoids live in environments that vary in resource availability and quality within and between generations. The use of information to adapt behavior to the current environment is a key feature under such circumstances and Drosophila parasitic wasps are excellent model systems to study learning and information use. They are among the few parasitoid model species that have been tested in a wide array of situations. Moreover, several related species have been tested under similar conditions, allowing the analysis of within and between species variability, the effect of natural selection in a typical environment, the current physiological status, and previous experience of the individual. This holds for host habitat and host location as well as for host choice and search time allocation. Here, we review patterns of learning and memory, of information use and updating mechanisms, and we point out that information use itself is under strong selective pressure and thus, optimized by parasitic wasps.

Modeling Environmental Influences in the Psyllaephagus bliteus (Hymenoptera: Encyrtidae)-Glycaspis brimblecombei (Hemiptera: Aphalaridae) Parasitoid-Host System.

Science.gov (United States)

Margiotta, M; Bella, S; Buffa, F; Caleca, V; Floris, I; Giorno, V; Lo Verde, G; Rapisarda, C; Sasso, R; Suma, P; Tortorici, F; Laudonia, S

2017-04-01

Glycaspis brimblecombei Moore (Hemiptera: Aphalaridae) is an invasive psyllid introduced into the Mediterranean area, where it affects several species of Eucalyptus. Psyllaephagus bliteus Riek (Hymenoptera: Encyrtidae) is a specialized parasitoid of this psyllid that was accidentally introduced into Italy in 2011. We developed a model of this host-parasitoid system that accounts for the influence of environmental conditions on the G. brimblecombei population dynamics and P. bliteus parasitism rates in the natural ecosystem. The Lotka-Volterra-based model predicts non-constant host growth and parasitoid mortality rates in association with variation in environmental conditions. The model was tested by analyzing sampling data collected in Naples in 2011 (before the parasitoid was present) and defining several environmental patterns, termed Temperature-Rain or T-R patterns, which correspond to the host growth rate. A mean value of the host growth rate was assigned to each T-R pattern, as well as a variation of the parasitoid mortality rate based on temperature thresholds. The proposed model was applied in simulation tests related to T-R patterns carried out with a data series sampled between June 2014 and July 2015 in five Italian sites located in Campania, Lazio, Sicily, and Sardinia regions. The simulation results showed that the proposed model provides an accurate approximation of population trends, although oscillation details may not be apparent. Results predict a 64% reduction in G. brimblecombei population density owing to P. bliteus parasitoid activity. Our results are discussed with respect to features of the host-parasitoid interaction that could be exploited in future biological control programs. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Habitat selection of a parasitoid mediated by volatiles informing on host and intraguild predator densities

DEFF Research Database (Denmark)

Cotes, Belén; Rännbäck, Linda Marie; Björkman, Maria

2015-01-01

both a parasitoid and its host, parasitoids may reduce the risk of intraguild predation (IGP) by avoiding such patches. In this study, we examined whether the presence of the entomopathogenic fungi Metarhizium brunneum and Beauveria bassiana in soil habitats of a root herbivore, Delia radicum, affects...

PERBANDINGAN KEANEKARAGAMAN HYMENOPTERA PARASITOID PADA AGROEKOSISTEM KEDELAI DENGAN APLIKASI DAN TANPA APLIKASI INSEKTISIDA

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Hendrival Hendrival

2017-04-01

Full Text Available Abstrak Sistem pengelolaan tanaman kedelai dengan penggunaan insektisida sintetik yang intensif akan menurunkan keanekaragaman jenis Hymenoptera parasitoid. Penelitian bertujuan untuk memban-dingkan keanekaragaman Hymenoptera parasitoid pada agroekosistem kedelai dengan dan tanpa aplikasi insektisida sintetik. Pengumpulan data serangga menggunakan perangkap dari jaring serangga dan nampan kuning. Hasil penelitian menunjukkan bahwa indeks keanekaragaman jenis pada fase pertumbuhan vegetatif dan generatif kedelai dengan aplikasi insektisida lebih rendah dibandingkan dengan yang tanpa aplikasi insektisida, yang keduanya tergolong sedang. Indeks kemerataan jenis pada fase pertumbuhan vegetatif dan generatif dari kedua agroekosistem kedelai tergolong tinggi. Indeks kekayaan jenis pada fase vegetatif dari agroekosistem kedelai dengan aplikasi insektisida tergolong rendah (0<2,3955≤2,5, sedangkan pada fase generatif tergolong sedang (0<3,6118≤4. Indeks kekayaan jenis pada fase vegetatif (0<2,6229≤4 dan generatif (0<3,8287≤4 dari agroekosistem kedelai tanpa aplikasi insektisida tergolong sedang. Komunitas Hymenoptera parasitoid pada agroekosistem kedelai tanpa aplikasi insektisida memiliki kemiripan lebih rendah daripada yang dengan aplikasi insektisida. Aplikasi insektisida mempengaruhi indeks kekayaan jenis pada fase generatif dan kemiripan komunitasnya, yaitu nilainya lebih rendah daripada yang tanpa insektisida. Abstract The management system of soybean agroecosystem with an intensive use of synthetic insecticides will reduce the diversity of parasitoid Hymenoptera species. The study aimed to compare the diversity of the parasitoids in soybean agroecosystem with and without insecticide application. The collection of the parasitoid used insect net and yellow tray. The results showed that the diversity index of the parasitoids during vegetative and generative growth of the soybean with the insecticide application was lower than the one without

Hymenopteran parasitoids associated with the banana-skipper Erionota thrax L. (Insecta: Lepidoptera, Hesperiidae in Java, Indonesia

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ERNIWATI

2011-04-01

Full Text Available Erniwati, Ubaidillah R (2011 Hymenopteran parasitoids associated with the banana-skipper Erionota thrax L. (Insecta: Lepidoptera, Hesperiidae in Java, Indonesia. Biodiversitas 12: 76-85. Hymenopteran parasitoids of banana-skipper Erionota thrax L. (Insecta: Lepidoptera, Hesperiidae from Java, Indonesia are reviewed and an illustrated key to 12 species is presented to include Theronia zebra zebra, Xanthopimpla gamsura, Casinaria sp., Charops sp., Cotesia (Apanteles erionotae, Brachymeria lasus, B. thracis, Ooencyrtus pallidipes, Anastatus sp., Pediobius erionotae, Agiommatus sumatraensis and Sympiesis sp. The surveys of the natural enemies of the banana-skipper were conducted in 1990-2006 in several localities in Java. The aim of this study was to assess the native natural enemies of E. thrax, especially the parasitic Hymenoptera. Infested eggs, larvae and pupae of E. thrax were collected and reared in the laboratory. Emerging parasitoids were preserved in both dry mounting and in 80% alcohol for the species identification. Members of families Braconidae, Ichneumonidae, Encyrtidae, Pteromalidae, Chalcididae, Eupelmidae and Eulophidae were recorded as parasitoids of the banana skipper E. thrax from Java, Indonesia. Species distribution and alternative hosts of the parasitoids are presented.

Host location by ichneumonid parasitoids is associated with nest dimensions of the host bee species.

Science.gov (United States)

Flores-Prado, L; Niemeyer, H M

2012-08-01

Parasitoid fitness depends on the ability of females to locate a host. In some species of Ichneumonoidea, female parasitoids detect potential hosts through vibratory cues emanating from them or through vibrational sounding produced by antennal tapping on the substrate. In this study, we (1) describe host location behaviors in Grotea gayi Spinola (Hymenoptera: Ichneumonidae) and Labena sp. on nests of Manuelia postica Spinola (Hymenoptera: Apidae), (2) compare nest dimensions between parasitized and unparasitized nests, (3) correlate the length of M. postica nests with the number of immature individuals developing, and (4) establish the relative proportion of parasitized nests along the breeding period of M. postica. Based on our results, we propose that these parasitoids use vibrational sounding as a host location mechanism and that they are able to assess host nest dimensions and choose those which may provide them with a higher fitness. Finally, we discuss an ancestral host-parasitoid relationship between Manuelia and ichneumonid species.

Genomic and karyotypic variation in Drosophila parasitoids (Hymenoptera, Cynipoidea, Figitidae

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Vladimir Gokhman

2011-08-01

Full Text Available Drosophila melanogaster Meigen, 1830 has served as a model insect for over a century. Sequencing of the 11 additional Drosophila Fallen, 1823 species marks substantial progress in comparative genomics of this genus. By comparison, practically nothing is known about the genome size or genome sequences of parasitic wasps of Drosophila. Here, we present the first comparative analysis of genome size and karyotype structures of Drosophila parasitoids of the Leptopilina Förster, 1869 and Ganaspis Förster, 1869 species. The gametic genome size of Ganaspis xanthopoda (Ashmead, 1896 is larger than those of the three Leptopilina species studied. The genome sizes of all parasitic wasps studied here are also larger than those known for all Drosophila species. Surprisingly, genome sizes of these Drosophila parasitoids exceed the average value known for all previously studied Hymenoptera. The haploid chromosome number of both Leptopilina heterotoma (Thomson, 1862 and L. victoriae Nordlander, 1980 is ten. A chromosomal fusion appears to have produced a distinct karyotype for L. boulardi (Barbotin, Carton et Keiner-Pillault, 1979 (n = 9, whose genome size is smaller than that of wasps of the L. heterotoma clade. Like L. boulardi, the haploid chromosome number for G. xanthopoda is also nine. Our studies reveal a positive, but non linear, correlation between the genome size and total chromosome length in Drosophila parasitoids. These Drosophila parasitoids differ widely in their host range, and utilize different infection strategies to overcome host defense. Their comparative genomics, in relation to their exceptionally well-characterized hosts, will prove to be valuable for understanding the molecular basis of the host-parasite arms race and how such mechanisms shape the genetic structures of insect communities.

Displacement of Aphytis chrysomphali by Aphytis melinus, parasitoids of the California red scale, in the Iberian Peninsula

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Juan Ramon Boyero

2014-02-01

Full Text Available Parasitoids are the main natural enemies of the California red scale, Aonidiella aurantii (Maskell and on occasion can regulate their populations. To increase their effectiveness, inoculative or augmentative releases of parasitoids are promoted. Previous to the implementation of any release strategy an important and necessary step is to acquire knowledge on the parasitoid fauna associated with this key phytophagous pest. Parasitoids were surveyed and quantified in Spanish citrus orchards between 2005 and 2009. Aphytis melinus DeBach (87.1% resulted as the dominant species, followed by Aphytis chrysomphali (Mercet (15.9%, Encarsia perniciosi (Tower (2.4% and Aphycus hederaceus (Westwood (0.004%. Overall, higher levels of parasitism were recorded in fruit than in twigs. Scales in fruit were parasitized at similar levels by the different parasitoid species whereas E. perniciosi was more active in twigs. Data eventually reveal the recent displacement of A. chrysomphali by A. melinus. The implications of these results on the biological control of A. aurantii are discussed and this information will be useful in the decision of IPM strategies for this pest.

Can the Understory Affect the Hymenoptera Parasitoids in a Eucalyptus Plantation?

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Onice Teresinha Dall'Oglio

Full Text Available The understory in forest plantations can increase richness and diversity of natural enemies due to greater plant species richness. The objective of this study was to test the hypothesis that the presence of the understory and climatic season in the region (wet or dry can increase the richness and abundance of Hymenoptera parasitoids in Eucalyptus plantations, in the municipality of Belo Oriente, Minas Gerais State, Brazil. In each eucalyptus cultivation (five areas of cultivation ten Malaise traps were installed, five with the understory and five without it. A total of 9,639 individuals from 30 families of the Hymenoptera parasitoids were collected, with Mymaridae, Scelionidae, Encyrtidae and Braconidae being the most collected ones with 4,934, 1,212, 619 and 612 individuals, respectively. The eucalyptus stands with and without the understory showed percentage of individuals 45.65% and 54.35% collected, respectively. The understory did not represent a positive effect on the overall abundance of the individuals Hymenoptera in the E. grandis stands, but rather exerted a positive effect on the specific families of the parasitoids of this order.

Can the Understory Affect the Hymenoptera Parasitoids in a Eucalyptus Plantation?

Science.gov (United States)

Dall’Oglio, Onice Teresinha; Ribeiro, Rafael Coelho; Ramalho, Francisco de Souza; Fernandes, Flávio Lemes; Wilcken, Carlos Frederico; de Assis Júnior, Sebastião Lourenço; Rueda, Rosa Angélica Plata; Serrão, José Eduardo; Zanuncio, José Cola

2016-01-01

The understory in forest plantations can increase richness and diversity of natural enemies due to greater plant species richness. The objective of this study was to test the hypothesis that the presence of the understory and climatic season in the region (wet or dry) can increase the richness and abundance of Hymenoptera parasitoids in Eucalyptus plantations, in the municipality of Belo Oriente, Minas Gerais State, Brazil. In each eucalyptus cultivation (five areas of cultivation) ten Malaise traps were installed, five with the understory and five without it. A total of 9,639 individuals from 30 families of the Hymenoptera parasitoids were collected, with Mymaridae, Scelionidae, Encyrtidae and Braconidae being the most collected ones with 4,934, 1,212, 619 and 612 individuals, respectively. The eucalyptus stands with and without the understory showed percentage of individuals 45.65% and 54.35% collected, respectively. The understory did not represent a positive effect on the overall abundance of the individuals Hymenoptera in the E. grandis stands, but rather exerted a positive effect on the specific families of the parasitoids of this order. PMID:26954578

Functional and evolutionary insights from the genomes of three parasitoid Nasonia species

DEFF Research Database (Denmark)

Werren, John H; Richards, Stephen; Desjardins, Christopher A

2010-01-01

We report here genome sequences and comparative analyses of three closely related parasitoid wasps: Nasonia vitripennis, N. giraulti, and N. longicornis. Parasitoids are important regulators of arthropod populations, including major agricultural pests and disease vectors, and Nasonia is an emerging...... of genes involved in nuclear-mitochondrial interactions that are implicated in speciation. Newly developed genome resources advance Nasonia for genetic research, accelerate mapping and cloning of quantitative trait loci, and will ultimately provide tools and knowledge for further increasing the utility...

Feeding status of the parasitoid Diadegma semiclausum affects biological control of Plutella xylostella: a simulation study

NARCIS (Netherlands)

Hemerik, L.

2007-01-01

Life history characteristics of the diamondback moth (DBM), Plutella xylostella, a worldwide pest on cruciferous crops, and its important natural enemy, the parasitoid Diadegma semiclausum have intensely been studied. In addition, the searching behaviour of the parasitoid and the role of foraging

Quality of different aphids as hosts of the parasitoid Lysiphlebus testaceipes (Cresson) (Hymenoptera: Braconidae, Aphidiinae); Qualidade de diferentes especies de pulgoes como hospedeiros do parasitoide Lysiphlebus testaceipes (Cresson) (Hymenoptera: Braconidae, Aphidiinae)

Energy Technology Data Exchange (ETDEWEB)

Silva, Robson J.; Bueno, Vanda H.P. [Universidade Federal de Lavras, MG (Brazil). Dept. de Entomologia]. E-mail: vhpbueno@ufla.br; Sampaio, Marcus V.[Universidade Federal de Uberlandia (UFU), MG (Brazil). Inst. de Ciencias Agrarias]. E-mail: mvsampaio@iciag.ufu.br

2008-03-15

Lysiphlebus testaceipes (Cresson) has a broad aphid host range; however the quality of these preys may interfere in its biological feature. This study aimed to evaluate the quality of three Macrosiphini, Brevicoryne brassicae (L.), Lipaphis erysimi (Kaltenbach) and Myzus persicae (Sulzer), and three Aphidini Schizaphis graminum (Rondani) Rhopalosiphum maidis (Fitch) and Aphis gossypii Glover as hosts to L. testaceipes and to determine the relation possible of host preference, of size and quality of the host. The tests were carried out in climatic chamber at 25 {+-} 1 deg C, RH 70 {+-} 10% and 12h photophase. The parasitoid did not oviposite in B. brassicae and L. erysimi, while the other species were nutritionally suitable to the parasitoid. L. testaceipes showed preference for aphids from tribe Aphidini and these hosts presented better quality to the parasitoid when compared to Macrosiphini. Interactions among size, preference and quality between the Aphidini were found. L. testaceipes showed preference (parasitism rate 76.7%) for R. maidis, the bigger host (hind tibia with 0.281 mm). This host provided bigger size (hind tibia with 0.49 mm) and higher emergence rate (95.6%) to the parasitoid when compared to A. gossypii (parasitism rate of 55.7%). Also the smaller host A. gossypii (0.266 mm) provided smaller size hind tibia (0.45 mm) and higher mortality of the parasitoid (emergence rate 72.1%). However, the development time was shorter and the longevity was higher in A. gossypii (6.3 and 5.4 days, respectively) when compared to the host R. maidis (6.7 and 3.8 days, respectively), and not been related to host size. (author)

Disease-parasitoid relationships in natural populations of Lymantria dispar [Lep.: Lymantriidae] in the northeastern United States

Science.gov (United States)

R.C. Reardon; J.D. Podgwaite

1976-01-01

Immature Lymantria dispar L. were collected from 6 geographically distinct populations over 2 years to determine correlations between parasitoid and disease incidences. Incidence of the nuclear polyhedrosis virus disease (NPV) was found to be positively correlated with incidences of the parasitoids Apanteles melanoscelus (Ratzeburg...

Aphid parasitoids (Hymenoptera, Braconidae, Aphidiinae) from Thailand

Czech Academy of Sciences Publication Activity Database

Starý, Petr; Rakhshani, E.; Tomanović, Ž.; Kavallieratos, N. G.; Sharkey, M.

-, č. 2498 (2010), s. 47-52 ISSN 1175-5326 Grant - others:Ministry of Science of the Republic of Serbia(CS) 143006B; U. S. National Science Foundation(US) DEB 0542864 Institutional research plan: CEZ:AV0Z50070508 Keywords : aphids * parasitoids * biodiversity Subject RIV: EG - Zoology Impact factor: 0.853, year: 2010

A review of hymenopterous parasitoid guilds attacking Anastrepha spp. and Ceratitis capitata (Diptera: Tephritidae) in Argentina

Energy Technology Data Exchange (ETDEWEB)

Ovruski, Sergio M.; Orono, Luis E.; Nunez-Campero, Segundo; Schliserman, Pablo; Albornoz-Medina, Patricia; Bezdjian, Laura P.; Nieuwenhove, Guido A. Van; Martin, Cristina B. [Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET), Tucuman (Argentina). Planta Piloto de Procesos Industriales Microbiologicos y Biotecnologia. Div. Control Biologico de Plagas

2006-07-01

This study provides detailed information on the diversity, abundance, guilds, host plant and host fly ranges, distribution, and taxonomic status of hymenopterous parasitoid species associated with Ceratitis capitata (Wiedemann) and Anastrepha spp. (A. fraterculus (Wiedemann) and A. schultzi Blanchard) in Argentina. Moreover, the article also argues future needs regarding the use of some parasitoid species as an alternative tool in fruit fly management programs of the National Fruit Fly Control and Eradication Program (PROCEM-Argentina). Data used for this work were obtained from numerous old and recent published articles on fruit fly parasitoids in Argentina. (author)

A review of hymenopterous parasitoid guilds attacking Anastrepha spp. and Ceratitis capitata (Diptera: Tephritidae) in Argentina

International Nuclear Information System (INIS)

Ovruski, Sergio M.; Orono, Luis E.; Nunez-Campero, Segundo; Schliserman, Pablo; Albornoz-Medina, Patricia; Bezdjian, Laura P.; Nieuwenhove, Guido A. Van; Martin, Cristina B.

2006-01-01

This study provides detailed information on the diversity, abundance, guilds, host plant and host fly ranges, distribution, and taxonomic status of hymenopterous parasitoid species associated with Ceratitis capitata (Wiedemann) and Anastrepha spp. (A. fraterculus (Wiedemann) and A. schultzi Blanchard) in Argentina. Moreover, the article also argues future needs regarding the use of some parasitoid species as an alternative tool in fruit fly management programs of the National Fruit Fly Control and Eradication Program (PROCEM-Argentina). Data used for this work were obtained from numerous old and recent published articles on fruit fly parasitoids in Argentina. (author)

Chemical Control for Host-Parasitoid Model within the Parasitism Season and Its Complex Dynamics

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Tao Wang

2016-01-01

Full Text Available In the present paper, we develop a host-parasitoid model with Holling type II functional response function and chemical control, which can be applied at any time of each parasitism season or pest generation, and focus on addressing the importance of the timing of application pesticide during the parasitism season or pest generation in successful pest control. Firstly, the existence and stability of both the host and parasitoid populations extinction equilibrium and parasitoid-free equilibrium have been investigated. Secondly, the effects of key parameters on the threshold conditions have been discussed in more detail, which shows the importance of pesticide application times on the pest control. Thirdly, the complex dynamics including multiple attractors coexistence, chaotic behavior, and initial sensitivity have been studied by using numerical bifurcation analyses. Finally, the uncertainty and sensitivity of all the parameters on the solutions of both the host and parasitoid populations are investigated, which can help us to determine the key parameters in designing the pest control strategy. The present research can help us to further understand the importance of timings of pesticide application in the pest control and to improve the classical chemical control and to make management decisions.

Hymenopterous parasitoids attacking Acanthiophilus helianthi Rossi (Diptera: Tephritidae pupae in Kohgiluyeh Safflower farms of Iran

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K. Saeidi

2016-12-01

Full Text Available The Safflower capsule fly (SCF, Acanthiophilus helianthi Rossi (Diptera: Tephritidae is the most destructive insect pest attacking the Safflower Carthamus tinctorius L. plant which are cultivated as an oil crop. It is mainly controlled through application of broad-spectrum insecticides, which can adversely affect safflower farms ecosystem and consequently human health. Since a first step in setting up an integrated pest management program is to assess the biological control agents within the ecosystem. Therefore, in this research work the pupal parasitoids of Safflower capsule fly a main insect pest attacking Safflower plants were identified. The impact of these parasitoids against this pest was evaluated on the varying pest generations and within different locations in Kohgiluyeh province during 2008-2009 seasons. Pupal parasitoid adults of SCF were recorded from fieldreared pupae, which had been collected from heavily infested small flower heads of the first generation as well from large flower heads of the second and third generations. Rate of parasitism on A. helianthi pupae was estimated as the number of parasitoids over the total count of parasitoids and flies. Ten hymenopterous species belonging to different families parasitizing insect pupae were screened as follows: Bracon hebetor (Spinola, 1808 and Bracon luteator (Spinola, 1808 (Braconidae; Isocolus tinctorious (Melika and Gharaei, 2006 (Cynipidae; Pronotalia carlinarum (Szelenyi and Erdos, 1951 (Eulophidae; Eurytoma acroptilae (Zerova, 1986 (Eurytomidae; Ormyrus orientalis (Walker, 1871 (Ormyridae; Colotrechnus viridis (Masi, 1921 and Pteromalus sp. (Walker, 1976 (Pteromalidae; and Antistrophoplex conthurnatus (Zerova, 2000 and Microdontomenus annulatus (Masi, 1899 (Torymidae. The average parasitization rate was 23±1 as revealed through the present study. The highest parasitization rate occurred during the first generation in all localities tested, as well as in years. Statistical

A two-component model of host–parasitoid interactions: determination of the size of inundative releases of parasitoids in biological pest contro

NARCIS (Netherlands)

Grasman, J.; Herwaarden, van O.A.; Hemerik, L.; Lenteren, van J.C.

2001-01-01

A two-component differential equation model is formulated for a host–parasitoid interaction. Transient dynamics and population crashes of this system are analysed using differential inequalities. Two different cases can be distinguished: either the intrinsic growth rate of the host population is

Clave dicotómica para especies parasitoides e hiperparasitoides (Hymenoptera de áfidos (Hemiptera: Aphididae de Costa Rica

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Daniel Zamora Mejías

2017-09-01

Full Text Available Los áfidos representan una problemática para muchas especies de plantas, debido a que son vectores de múltiples patógenos; el control biológico mediante el uso de parasitoides es una opción permanente de control de sus poblaciones. El objetivo de esta investigación fue elaborar una clave dicotómica para identificar parasitoides e hiperparasitoides de áfidos recolectados en Costa Rica. Se obtuvo desde el año 2008 hasta 2015 un total de 3009 parasitoides himenópteros de 25 especies de áfidos, de los cuales 2832 (94% se clasificaron como parasitoides primarios y 175 (6% como hiperparasitoides. Se elaboró una clave de identificación para nueve especies de parasitoides primarios Braconidae-Aphidiinae, Aphelinidae, Eulophidae y cinco familias de hiperparasitoides comprendidos en seis especies. Además, se incluye en la clave el género Quadrictonus (Aphidiinae, el cual se registró por primera vez para Costa Rica en este estudio.

Potential use of F1 sterility and the parasitoid, Cotesia plutellae, to control diamondback moth, Plutella xylostella, in Myanmar

International Nuclear Information System (INIS)

Maung, N.

2002-01-01

Diamondback moth (DBM), Plutella xylostella males irradiated with 100 Gy and larval parasitoids (Cotesia plutellae) were studied for their potential to control DBM in cabbage fields of Nyaung-Le-Bin Township, Bago Division. The following treatments were evaluated as control tactics: release of irradiated male DBM, augmentative release of parasitoids, and combined release of irradiated male DBM and parasitoids. These treatments reduced the larval population of feral DBM. (author)

Toxicity of organic supplies for the egg parasitoid Telenomus podisi

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Débora Mello da Silva

2014-01-01

Full Text Available Toxicity (dosage per hectare of: 1 Baculovirus anticarsia 140x109 cpi; 2 Bacillus thuringiensis 16.8g; 3 Azadirachtin-A, azadirachtin-B, nimbina and salamina 9.6 ppm; 4 Rotenoids 4 liters; 5 Nitrogen 1.3%, phosphorus 3.0% and total organic carbon 8.0% 3 liters; 6 Sodium silicate 2% 4 liters; 7 Copper 7% + calcium 3.3% 1.8 liters; 8 Sulfur 20% + quicklime 10% 1.8 liters; 9 Chlorpyrifos 384g; 10 Distilled H2O (control were evaluated for pupae and adults of Telenomus podisi. Treatments from 1 to 8 were in general harmless (class 1 to both pupae and adults of T. podisi. Among them, only treatment 5 and 7 presented slightly toxic to the parasitoid with a reduction in parasitism 5 days after F1 parasitoid emergence. Differently, the chlorpyrifos was classified as slightly harmful (class 2 or moderately harmful (class 3. Therefore, the use of the tested organic agricultural supplies in the production of organic soybean is viable, without impairing the natural biological control allowed by this egg parasitoid. Chlorpyrifos use, on the other hand, is not allowed in organic soybean, but even on convention crop production, could whenever possible, be replaced by other products more compatible with T. podisi preservation.

An assessment of interspecific competition between two introduced parasitoids of Diaphorina citri (Hemiptera: Liviidae) on caged citrus plants.

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Vankosky, Meghan A; Hoddle, Mark S

2017-06-07

Two parasitoids attacking nymphs of Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), Tamarixia radiata (Waterston) (Hymenoptera: Eulophidae) and Diaphorencyrtus aligarhensis (Shafee, Alam & Agarwal) (Hymenoptera: Encyrtidae) are being released in California, USA in a classical biological control program. To evaluate the effect of multiple parasitoid species on D. citri mortality, we conducted mesocosm experiments under controlled conditions using a complete block design with 6 treatments (D. citri nymphs exposed to: no parasitoids; D. aligarhensis or T. radiata alone; D. aligarhensis or T. radiata released first (by 48 h); and both species released simultaneously). Parasitism of D. citri nymphs by T. radiata exceeded 60% and was unchanged when D. aligarhensis were present. Parasitism by D. aligarhensis was greatest when T. radiata was absent (∼28%) and was reduced in all treatments with T. radiata present (citri mortality and parasitoid-related mortality of D. citri was consistent across parasitoid treatments. Laboratory results suggest that competition between D. aligarhensis and T. radiata is asymmetric and favors T. radiata. It may be difficult for D. aligarhensis to contribute significantly to D. citri biological control where T. radiata is present. However, results reported here suggest that competition between T. radiata and D. aligarhensis is not likely to reduce parasitism by T. radiata or reduce parasitoid-induced mortality of D. citri. © 2017 Institute of Zoology, Chinese Academy of Sciences.

At Lunch with a Killer: The Effect of Weaver Ants on Host-Parasitoid Interactions on Mango.

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Valentina Migani

Full Text Available Predator-prey interactions can affect the behaviour of the species involved, with consequences for population distribution and competitive interactions. Under predation pressure, potential prey may adopt evasive strategies. These responses can be costly and could impact population growth. As some prey species may be more affected than others, predation pressure could also alter the dynamics among species within communities. In field cages and small observation cages, we studied the interactions between a generalist predator, the African weaver ant, Oecophylla longinoda, two species of fruit flies that are primary pests of mango fruits, Ceratitis cosyra and Bactrocera dorsalis, and their two exotic parasitoids, Fopius arisanus and Diachasmimorpha longicaudata. In all experiments, either a single individual (observation cage experiments or groups of individuals (field cage experiments of a single species were exposed to foraging in the presence or absence of weaver ants. Weaver ant presence reduced the number of eggs laid by 75 and 50 percent in B. dorsalis and C. cosyra respectively. Similarly, parasitoid reproductive success was negatively affected by ant presence, with success of parasitism reduced by around 50 percent for both F. arisanus and D. longicaudata. The negative effect of weaver ants on both flies and parasitoids was mainly due to indirect predation effects. Encounters with weaver ant workers increased the leaving tendency in flies and parasitoids, thus reduced the time spent foraging on mango fruits. Parasitoids were impacted more strongly than fruit flies. We discuss how weaver ant predation pressure may affect the population dynamics of the fruit flies, and, in turn, how the alteration of host dynamics could impact parasitoid foraging behaviour and success.

Keanekaragaman spesies parasitoid telur Helicoverpa armigera (Hübner pada sistem tanam monokultur dan polikultur kapas

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nurindah nurindah

2017-02-01

Full Text Available Polyculture system is one of techniques in pest management. In Indonesia, cotton is always intercropped with second food crops such as maize, soybean, mungbean or peanut. This research was aimed to evaluate the effect of culture system, i.e. cotton monoculture vs. cotton intercropped with soybean on the increase of species diversity of H. armigera egg parasitoids and the parasitoid contribution to mortality of H. armigera. The research was arranged in a split plot design with two main factors: three cotton varieties with three levels of trichome density (Tamcot SP 37, Kanesia 8 and LRA 5166 and the subplots were two cultivation systems (cotton monoculture and polyculture, with three replicates. Observations were made by collecting H. armigera eggs on population of first generation (45 days after planting and second generation (75 DAP. The results showed that on cotton polyculture the egg parasitoid complex which consisted of Trichogramma spp. and Trichogrammatoidea spp. was higher than that in cotton monoculture and so was the egg parasitism level. The increase of egg parasitism was 24% in the first generation and 15% in the second generation. Parasitoid species found belonged to the genera Trichogramma and Trichogrammatoidea. In the parasitoid complex, Trichogrammatoidea armigera was dominant on the first generation and Trichogramma chilotraeae on the second. The domination succession could be as a result of the higher host-searching capacity of T. chilotraeae than that of T. armigera.

The Roles of Parasitoid Foraging for Hosts, Food and Mates in the Augmentative Control of Tephritidae.

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Sivinski, John; Aluja, Martin

2012-07-20

Ultimately, the success of augmentative fruit fly biological control depends upon the survival, dispersal, attack rate and multi-generational persistence of mass-reared parasitoids in the field. Foraging for hosts, food and mates is fundamental to the above and, at an operational level, the choice of the parasitoid best suited to control a particular tephritid in a certain environment, release rate estimates and subsequent monitoring of effectiveness. In the following we review landscape-level and microhabitat foraging preferences, host/fruit ranges, orientation through environmental cues, host vulnerabilities/ovipositor structures, and inter and intraspecific competition. We also consider tephritid parasitoid mating systems and sexual signals, and suggest the directions of future research.

Pengujian kekhususan inang parasitoid Anagyrus lopezi (De Santis (Hymenoptera: Encyrtidae pada empat spesies kutu putih yang berasosiasi dengan tanaman singkong

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Rani Dessy Karyani

2016-12-01

Full Text Available A parasitoid, Anagyrus lopezi (De Santis (Hymenoptera: Encyrtidae was introduced from Thailand into Indonesia  in early 2014 to control the cassava mealybug Phenacoccus manihoti Matile-Ferrero (Hemiptera: Pseudococcidae. To determine its potential uses and effect on non-target species, behavioural observation of the parasitoids were made on four species of mealybugs, i.e. P. manihoti, Paracoccus marginatus Williams-Granara de Willink, Pseudococcus jackbeardsleyi Gimpel-Miller, and Ferrisia virgata Cockerell (Hemiptera: Pseudococcidae. For that purposes, a set of tests were conducted wich includes host susceptability, preference, and suitability. Tests were conducted by exposing a female parasitoid to 3rd instar nymphs of each mealybug species in a petri dish. For susceptability test, parasitoid A. lopezi encounterend P. manihoti more often (13.70 ± 7.18 visits per 30 minutes as compared to P. marginatus (985 ± 10.24, P. jackbeardsleyi (6.60 ± 3.62, and F. virgata (5.75 ± 4.09. So did ovipositor probing occurred more on P. manihoti (8.20 ± 5.68 probes per 30 minutes than on P. marginatus (0.70 ± 1.84, P. jackbeardsleyi (0.35 ± 0.68, and F. virgata (0.10 ± 0.45. For preference test, host encounter and ovipositor probing by the parasitoid were more common on P. manihoti as opposed to other mealybug species. Out of four mealybug species tested, P. manihoti was the only suitable host for parasitoid development, with the number of progenies emerged 7.40 ± 2.17 individuals per 3 female parasitoids exposed in 24 hour. Host specifity exhibited by parasitoid A. lopezi may prevent adverse effect to other mealybug species inhabiting cassava fields.

Complex dynamics and bifurcation analysis of host–parasitoid models with impulsive control strategy

International Nuclear Information System (INIS)

Yang, Jin; Tang, Sanyi; Tan, Yuanshun

2016-01-01

Highlights: • We develop novel host-parasitoid models with impulsive control strategy. • The effects of key parameters on the successful control have been addressed. • The complex dynamics and related biological significance are investigated. • The results between two types of host-parasitoid models have been discussed. - Abstract: In this paper, we propose and analyse two type host–parasitoid models with integrated pest management (IPM) interventions as impulsive control strategies. For fixed pulsed model, the threshold condition for the global stability of the host-eradication periodic solution is provided, and the effects of key parameters including the impulsive period, proportionate killing rate, instantaneous search rate, releasing constant, survival rate and the proportionate release rate on the threshold condition are discussed. Then latin hypercube sampling /partial rank correlation coefficients are used to carry out sensitivity analyses to determine the significance of each parameters. Further, bifurcation analyses are presented and the results show that coexistence of attractors existed for a wide range of parameters, and the switch-like transitions among these attractors indicate that varying dosages and frequencies of insecticide applications and numbers of parasitoid released are crucial for IPM strategy. For unfixed pulsed model, the results show that this model exists very complex dynamics and the host population can be controlled below ET, and it implies that the modelling methods are helpful for improving optimal strategies to design appropriate IPM.

Parasitoid dan Parasitisasi Plutella xylostella (L. (Lepidoptera: Yponomeutidae di Sumatera Selatan

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SITI HERLINDA

2005-12-01

Full Text Available Surveys from May 2003 to January 2004 in South Sumatera were conducted to determine parasitoid attacking Plutella xylostella (L. and to estimate P. xylostella parasitization by the parasitoids. The eggs and the larvae of P. xylostella were collected from brassicaceous crops, i.e. mustard, Indian mustard, and cabbage. Six parasitoids found were Trichogrammatoidea cojuangcoi Nagaraja (Hymenoptera: Trichogrammatidae, Cotesia plutellae (Kurdj. (Hymenoptera: Braconidae, Diadegma semiclausum Hellen (Hymenoptera: Ichneumonidae, Oomyzus sokolowskii (Kurdj. (Hymenoptera: Eulophidae, Tetrastichus (Hymenoptera: Eulophidae, and a ceraphronid wasp (unidentified species. Trichogrammatoidea cojuangcoi parasitized P. xylostella eggs, however, the others parasitized the larvae except the ceraphronid wasp. In South Sumatera, the ceraphronid wasp was reported for the first time parasitizing D. semiclausum pupae, and its parasitization reached 6.2%. Oomyzus sokolowskii and Tetrastichus were found in this area for the first time, as well. In the highland, D. semiclausum was the most abundant compared to the others where its parasitization reached 79.2%. In the lowland P. xylostella larvae was mainly attacked by C. plutellae with the parasitization reaching 64.9% In the dry and rainy seasons, the parasitization was mainly exerted by T. cojuangcoi (77.0% and D. semiclausum (79.2%.

The role of herbivore- and plant-related experiences in intraspecific host preference of a relatively specialized parasitoid.

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Morawo, Tolulope; Fadamiro, Henry

2017-09-06

Parasitoids use odor cues from infested plants and herbivore hosts to locate their hosts. Specialist parasitoids of generalist herbivores are predicted to rely more on herbivore-derived cues than plant-derived cues. Microplitis croceipes (Cresson) (Hymenoptera: Braconidae) is a relatively specialized larval endoparasitoid of Heliothis virescens (F.) (Lepidoptera: Noctuidae), which is a generalist herbivore on several crops including cotton and soybean. Using M. croceipes/H. virescens as a model system, we tested the following predictions about specialist parasitoids of generalist herbivores: (i) naive parasitoids will show innate responses to herbivore-emitted kairomones, regardless of host plant identity and (ii) herbivore-related experience will have a greater influence on intraspecific oviposition preference than plant-related experience. Inexperienced (naive) female M. croceipes did not discriminate between cotton-fed and soybean-fed H. virescens in oviposition choice tests, supporting our first prediction. Oviposition experience alone with either host group influenced subsequent oviposition preference while experience with infested plants alone did not elicit preference in M. croceipes, supporting our second prediction. Furthermore, associative learning of oviposition with host-damaged plants facilitated host location. Interestingly, naive parasitoids attacked more soybean-fed than cotton-fed host larvae in two-choice tests when a background of host-infested cotton odor was supplied, and vice versa. This suggests that plant volatiles may have created an olfactory contrast effect. We discussed ecological significance of the results and concluded that both plant- and herbivore-related experiences play important role in parasitoid host foraging. © 2017 Institute of Zoology, Chinese Academy of Sciences.

Effects of various insecticides on the development of the egg parasitoid Trichogramma dendrolimi (Hymenoptera: Trichogrammatidae).

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Takada, Y; Kawamura, S; Tanaka, T

2001-12-01

The toxicity of six insecticides, acephate, methomyl, ethofenprox, cartap, chlorfluazuron, and Bacillus thuringiensis (Bt) was tested on different developmental stages of the egg parasitoid, Trichogramma dendrolimi (Matsumura). Each of the insecticides tested showed different degrees of toxicity to the parasitoid, Ethofenprox showed the highest toxicity and cartap showed relatively higher toxicity compared with the other insecticides. The development of the parasitoids treated with these two insecticides was normal, similar to that of the control group. Only the emergence of adult wasps from host eggs was disturbed. Emergence of the host, Mamestra brassicae larva was reduced following treatment with ethofenprox, cartap and methomyl. However, adult female wasps, which emerged from host eggs treated with the insecticides had the ability to oviposit normally.

Parasitoids of the endangered leafcutter ant Atta robusta Borgmeier in urban and natural areas

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Diego S. Gomes

2013-09-01

Full Text Available Parasitoids of the endangered leafcutter ant Atta robusta Borgmeier in urban and natural areas. Hosts of parasitoids in urban areas may suffer from a double threat of habitat destruction by urbanization and parasitism pressure. Moreover, the parasitoids themselves might be at risk if they are specialists. Here, we studied whether Atta robusta (Hymenoptera, Formicidae, which is on the red list of Brazilian threatened species, suffers from higher parasitism pressure in an urban area compared to a natural one. In addition, we determined whether their specialist parasitoids, Eibesfeldtphora breviloba and Myrmosicarius exrobusta (Diptera, Phoridae, are in risk and evaluated whether they are influenced by habitat structure, temperature, humidity, ant traffic, and time of the day. The study was carried out in an urban park and in a natural protected area in the city of Rio de Janeiro. In each site we chose an open area and a closed area (forest and sampled nine nests in each area. We found that parasitism pressure was similar in urban and natural areas, with the same two parasitoid species present in both areas. The main difference was related to habitat structure, since M. exrobusta was mainly present in open areas while E. breviloba was almost exclusively found in closed areas. Myrmosicarius exrobusta was not present during the hottest midday times, and its abundance was negatively correlated to vapor pressure deficit. These results suggest that green areas can be an important component in efforts to conserve diversity in urban areas. However, the complexity of the habitats in those areas is a fundamental issue in designing urban parks.

The influence of flower morphology and nectar quality on the longevity of a parasitoid biological control agent

NARCIS (Netherlands)

Vattala, H.D.; Wratten, S.D.; Phillips, C.B.; Wäckers, F.L.

2006-01-01

Conservation biological control aims to enhance the efficacy of arthropod biological control agents, such as parasitoids, partly by providing them with access to floral nectar. However, the suitability of a flower species for providing nectar to a parasitoid is dependent on the morphologies of the

Attack and Success of Native and Exotic Parasitoids on Eggs of Halyomorpha halys in Three Maryland Habitats.

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Megan V Herlihy

Full Text Available Egg parasitoids of the exotic invasive brown marmorated stink bug, Halyomorpha halys (Stål, were investigated using lab-reared fresh (live and frozen (killed lab-reared sentinel egg masses deployed for 72h on foliage in three habitats-woods, orchard, and soybean field-in Maryland, USA, in summer 2014. Four native hymenopteran species, Telenomus podisi Ashmead (Scelionidae, Trissolcus euschisti (Ashmead and Tr. brochymenae Ashmead (Scelionidae, and Anastatus reduvii (Howard (Eupelmidae, developed and emerged from H. halys eggs. One exotic parasitoid, Trissolcus japonicus (Ashmead, emerged, providing the first known occurrence of this species in North America. Native parasitoids emerged from frozen eggs significantly more often than from fresh eggs (89.3% of egg masses and 98.1% of individual eggs, whereas the exotic Tr. japonicus did not show a similar difference, strongly suggesting adaptation to H. halys as a host by Tr. japonicus but not by the native species. Parasitoids were habitat-specific: all three Trissolcus species were significantly more likely to occur in the woods habitat, whereas Te. podisi was found exclusively in the soybean field. Further investigations are required to elucidate evolving host-parasitoid relationships, habitat specificity, and non-target effects of Tr. japonicus over the expanded range of H. halys in North America.

Parasitoids of boll weevil Anthonomus grandis and resident predators in kaolin-treated cotton

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Roberta Leme Santos

2013-12-01

Full Text Available Simultaneous use of control methods is essential to reach success in managing arthropod pests. The current study investigated the effect of kaolin application on resident predators in the cotton plant canopy and parasitism of boll weevil on abscised squares in the field, and parasitism of boll weevil in the laboratory. Predators Araneae, Formicidae, Chrysopidae, and Coccinellidae showed similar seasonal densities for kaolin-treated and untreated cotton fields as well as the emergence rate of the parasitoids Bracon vulgaris Ashmead (Hymenoptera: Braconidae and Catolaccus grandis Burks (Hymenoptera: Pteromalidae from abscised field-collected structures. Under laboratory conditions, the parasitism of boll weevil larvae infesting squares was similar when treated and untreated squares with kaolin were offered to the parasitoid under free choice test. Therefore, the results show that spraying cotton fields with kaolin does not affect the natural biological control by parasitoids of boll weevil and pink bollworm and resident predators naturally occurring in cotton fields.

Study of two conditioning methods of parasitoids used in biological control prior to inundative releases in apple orchards

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Valérie-Anne Dumont

2011-12-01

Full Text Available The rosy apple aphid, Dysaphis plantaginea Pass., is a major pest in apple orchards in Belgium. Two micro-hymenopteran parasitoids Aphidius matricariae Haliday and Ephedrus cerasicola Stary are potentially capable of controlling this pest. However, when released in orchards the adult parasitoids tend to disperse. Based on the results of previous work it is proposed that the reason is that the artificial diet in which they are raised does not contain the odors that enable the parasitoids to identify the habitat where there are suitable aphid hosts. To optimize the control and make it economically effective it is important to reduce dispersal. This might be done by conditioning parasitoids during rearing by exposing them to the odors associated with orchards. The odor used in this study was a hydrodistillate of apple leaves, the main host-plant of the targeted aphid. Two methods of conditioning were used: 1 soaking mummies of the parasitoid in p ure hydrodistillate, 2 including a defined concentration of hydrodistillate in the artificial diet used for rearing the parasitoid. They were exposed to either a dilution of 100×, 200× and 1000× in two consecutive generations. The response of adult parasitoids to odors was determined using a dual choice olfactometer. Of the E. cerasicola conditioned by soaking the mummies 70–75% of individuals were attracted to the odor of plants infested with D. plantaginea compared to the 55–60% in the controls. The A.matricariae that were conditioned by feeding them artificial diets containing different concentrations of apple odor for one or two generations, showed no preference for the odor of apple leaves. Second generation adults of E. cerasicola exposed to a 200 times dilution of pure hydrodistillate showed a more marked response to apple odor.

Host Plants Affect the Foraging Success of Two Parasitoids that Attack Light Brown Apple Moth Epiphyas postvittana (Walker (Lepidoptera: Tortricidae.

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Yi Feng

Full Text Available The light brown apple moth, Epiphyas postvittana is a key pest of wine grapes in Australia. Two parasitoids, Dolichogenidea tasmanica and Therophilus unimaculatus, attack the larval stage of this pest. D. tasmanica is dominant in vineyards, whereas T. unimaculatus is mainly active in native vegetation. We sought to understand why they differ in their use of habitats. Plants are a major component of habitats of parasitoids, and herbivore-infested plants influence parasitoid foraging efficiency by their architecture and emission of volatile chemicals. We investigated how different plant species infested by E. postvittana could affect the foraging success of the two parasitoid species in both laboratory and field experiments. Four common host-plant species were selected for this study. In paired-choice experiments to determine the innate foraging preferences for plants, both parasitoid species showed differences in innate search preferences among plant species. The plant preference of D. tasmanica was altered by oviposition experience with hosts that were feeding on other plant species. In a behavioral assay, the two parasitoid species allocated their times engaged in various types of behavior differently when foraging on different plant species. For both parasitoids, parasitism on Hardenbergia violacea was the highest of the four plant species. Significantly more larvae dropped from Myoporum insulare when attacked than from the other three host-plant species, which indicates that parasitism is also affected by interactions between plants and host insects. In vineyards, parasitism by D. tasmanica was significantly lower on M. insulare than on the other three host-plant species, but the parasitism rates were similar among the other three plant species. Our results indicate that plants play a role in the habitat preferences of these two parasitoid species by influencing their foraging behavior, and are likely to contribute to their distributions

Innate Host Habitat Preference in the Parasitoid Diachasmimorpha longicaudata: Functional Significance and Modifications through Learning.

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Diego F Segura

Full Text Available Parasitoids searching for polyphagous herbivores can find their hosts in a variety of habitats. Under this scenario, chemical cues from the host habitat (not related to the host represent poor indicators of host location. Hence, it is unlikely that naïve females show a strong response to host habitat cues, which would become important only if the parasitoids learn to associate such cues to the host presence. This concept does not consider that habitats can vary in profitability or host nutritional quality, which according to the optimal foraging theory and the preference-performance hypothesis (respectively could shape the way in which parasitoids make use of chemical cues from the host habitat. We assessed innate preference in the fruit fly parasitoid Diachasmimorpha longicaudata among chemical cues from four host habitats (apple, fig, orange and peach using a Y-tube olfactometer. Contrary to what was predicted, we found a hierarchic pattern of preference. The parasitism rate realized on these fruit species and the weight of the host correlates positively, to some extent, with the preference pattern, whereas preference did not correlate with survival and fecundity of the progeny. As expected for a parasitoid foraging for generalist hosts, habitat preference changed markedly depending on their previous experience and the abundance of hosts. These findings suggest that the pattern of preference for host habitats is attributable to differences in encounter rate and host quality. Host habitat preference seems to be, however, quite plastic and easily modified according to the information obtained during foraging.

The Roles of Parasitoid Foraging for Hosts, Food and Mates in the Augmentative Control of Tephritidae

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Martin Aluja

2012-07-01

Full Text Available Ultimately, the success of augmentative fruit fly biological control depends upon the survival, dispersal, attack rate and multi-generational persistence of mass-reared parasitoids in the field. Foraging for hosts, food and mates is fundamental to the above and, at an operational level, the choice of the parasitoid best suited to control a particular tephritid in a certain environment, release rate estimates and subsequent monitoring of effectiveness. In the following we review landscape-level and microhabitat foraging preferences, host/fruit ranges, orientation through environmental cues, host vulnerabilities/ovipositor structures, and inter and intraspecific competition. We also consider tephritid parasitoid mating systems and sexual signals, and suggest the directions of future research.

Honey and honey-based sugars partially affect reproductive trade-offs in parasitoids exhibiting different life-history and reproductive strategies.

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Harvey, Jeffrey A; Essens, Tijl A; Las, Rutger A; van Veen, Cindy; Visser, Bertanne; Ellers, Jacintha; Heinen, Robin; Gols, Rieta

2017-04-01

Adult dietary regimes in insects may affect egg production, fecundity and ultimately fitness. This is especially relevant in parasitoid wasps where many species serve as important biological control agents of agricultural pests. Here, we tested the effect of honey and sugar diets on daily fecundity schedules, lifetime reproductive success and longevity in four species of parasitoid wasps when reared on their respective hosts. The parasitoid species were selected based on dichotomies in host usage strategies and reproductive traits. Gelis agilis and G. areator are idiobiont ecto-parasitoids that develop in non-growing hosts, feed on protein-rich host fluids to maximize reproduction as adults and produce small numbers of large eggs. Meteorus pulchricornis and Microplitis mediator are koinobiont endoparasitoids that develop inside the bodies of growing hosts, do not host-feed, and produce greater numbers of small eggs. Parasitoids were reared on diets of either pure honey (containing trace amounts of proteins), heated honey (with denatured proteins) and a honey-mimic containing sugars only. We hypothesized that the benefits of proteins in honey would enhance reproduction in the ectoparasitoids due to their high metabolic investment per egg, but not in the koinobionts. Pure honey diet resulted in higher lifetime fecundity in G. agilis compared with the honey-mimic, whereas in both koinobionts, reproductive success did not vary significantly with diet. Longevity was less affected by diet in all of the parasitoids, although there were variable trade-offs between host access and longevity in the four species. We argue that there are both trait-based and association-specific effects of supplementary nutrients in honey on reproductive investment and success in parasitoid wasps. Copyright © 2016 Elsevier Ltd. All rights reserved.

Biological control of Indianmeal moth (Lepidoptera: Pyralidae) on finished stored products using egg and larval parasitoids.

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Grieshop, Matthew J; Flinn, Paul W; Nechols, James R

2006-08-01

Biological control using hymenopteran parasitoids presents an attractive alternative to insecticides for reducing infestations and damage from the Indianmeal moth, Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae), in retail and warehouse environments. We examined the potential for using combinations of the egg parasitoid Trichogramma deion Riley (Hymenoptera: Trichogrammatidae), and the larval parasitoid Habrobracon hebetor (Say) (Hymenoptera: Braconidae) for preventing infestations of P. interpunctella in coarse-ground cornmeal as well as the influence of packaging on parasitoid effectiveness. Treatments included one or both parasitoids and either cornmeal infested with P. interpunctella eggs or eggs deposited on the surface of plastic bags containing cornmeal. H. hebetor had a significant impact on the number of live P. interpunctella, suppressing populations by approximately 71% in both unbagged and bagged cornmeal. In contrast, T. deion did not suppress P. interpunctella in unbagged cornmeal. However, when released on bagged cornmeal, T. deion significantly increased the level of pest suppression (87%) over bagging alone (15%). When H. hebetor was added to bagged cornmeal, there was a significant reduction of live P. interpunctella compared with the control (70.6%), with a further reduction observed when T. deion was added (96.7%). These findings suggest that, in most situations, a combined release of both T. deion and H. hebetor would have the greatest impact; because even though packaging may protect most of the stored products, there are usually areas in the storage landscape where poor sanitation is present.

Asociaciones áfido-parasitoide (Hemiptera: Aphididae; Hymenoptera: Braconidae, Aphidiinae en cultivos hortícolas orgánicos en Los Cardales, Buenos Aires, Argentina Aphid-parasitoid associations (Hemiptera: Aphididae; Hymenoptera: Braconidae, Aphidiinae on organic vegetable crops in Los Cardales, Buenos Aires, Argentina

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Andrea V. Andorno

2007-07-01

Full Text Available Diez especies de áfidos (Hemiptera: Aphididae se hallaron parasitados por siete especies de parasitoides (Hymenoptera: Braconidae, Aphidiinae en cultivos hortícolas orgánicos. Myzus persicae (Sulzer fue el áfido más frecuentemente encontrado sobre una amplia variedad de cultivos, y con mayor diversidad de parasitoides asociados. Aphidius colemani Viereck fue el afidiino más usual, que ataca varias especies de áfidos. Ocho asociaciones tritróficas, involucrando Aphidius matricariae Haliday, han sido registradas por primera vez para la Argentina.Ten aphid species (Hemiptera: Aphididae were found parasitized by seven aphid parasitoid species (Hymenoptera: Braconidae, Aphidiinae on organic vegetable crops. Myzus persicae (Sulzer was the most frequent aphid found on a wide variety of crops, with the largest parasitoid diversity associated. Aphidius colemani Viereck was the most frequent aphidiine attacking several species of aphids. Eight tritrophic associations involving Aphidius matricariae Haliday are reported for the first time for Argentina.

Species diversity and activity of parasitoids of the sweetpotato ...

African Journals Online (AJOL)

The species range, activity and relative abundance of parasitoids attacking the sweetpotato butterfly, Acraea acerata Hew. (Lepidoptera: Nymphalidae) in Uganda was investigated. Samples of eggs and larvae of the sweetpotato butterfly were collected from some of the major sweetpotato growing districts of Uganda to ...

Aphid parasitoid (Hymenoptera:Braconidae: Aphidiinae) in wetland habitats in western Palearctic: key and associated aphid parasitoid guilds

Czech Academy of Sciences Publication Activity Database

Tomanović, Ž.; Starý, Petr; Kavallieratos, N. G.; Gagić, V.; Plećaš, M.; Janković, M.; Rakhshani, E.; Ćetković, A.; Petrović, A.

2012-01-01

Roč. 48, 1-2 (2012), s. 189-198 ISSN 0037-9271 Grant - others:The Ministry of Science and Technological Development of the Republic of Serbia(RS) 043001 Institutional research plan: CEZ:AV0Z50070508 Keywords : aphid parasitoids * tritrophic interactions * wetlands Subject RIV: EH - Ecology, Behaviour Impact factor: 0.529, year: 2012 http://zoologie.umh.ac.be/asef/pdf/2012_48_01_02/full/Tomanovic_et_al_2012_ASEF_48_1_2_189_198_full.pdf

Producción masiva y simultánea de machos de Ceratitis capitata (Diptera: Tephritidae y parasitoides Dichasmimorpha longicaudata (Hymenoptera: Braconidae Massive and simultaneous production of Ceratitis capitata (Diptera: Tephritidae males and Diachasmimorpha longicaudata (Hymenoptera: Braconidae parasitoids

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Silvia N. López

2006-12-01

Full Text Available En la línea de sexado genético «Cast191» las hembras de Ceratitis capitata son homocigotas para el gen slow , lo que reduce su velocidad de desarrollo; los machos son heterocigotas y muestran una velocidad de desarrollo normal. Esta característica permitió producir, con Cast191, machos estériles por un lado, y parasitoides criados sobre las larvas remanentes por el otro. Nuestro objetivo con este trabajo fue producir ambos insumos simultáneamente y a una escala mayor que hasta ahora. Además, bajo estas condiciones, y en un intento por aumentar la separación entre sexos, se aplicó a las larvas del primer estadío un pulso de 15º C, durante 1 ó 2 días, luego del cual se las mantuvo a 20º C ó 25º C, hasta que entraron al estado de pupa, luego se mantuvo todo el material a 25º C. La mejor separación de sexos, lograda con el tratamiento a 20º C sin pulso de frío, se usó para comparar la calidad del parasitoide Diachasmimorpha longicaudata, criado sobre las larvas obtenidas tras la separación de los machos, con aquellos criados sobre la línea salvaje. Para ello, este tratamiento de separación fue aplicado en la cría de la mosca, y el material remanente de dieta con larvas fue expuesto al parasitoide. La tasa de parasitismo obtenida fue semejante a la hallada sobre la línea salvaje, y la tasa sexual de la F 1 del parasitoide presentó un sesgo hacia las hembras aún mayor. Se discute la factibilidad de utilizar la línea Cast191 de C. Capitata, para la producción a mayor escala de machos de mosca y para la cría masiva del parasitoide D. longicaudata.In the genetic sexing strain «Cast191», the females of Ceratitis capitata are homozygous for the mutation slow , slowing down their rate of development, and the males are heterozygous, having a normal rate of development. This feature made Cast191 capable of producing sterile males, on one hand, and parasitoids that are reared on the remaining larvae, on the other. The

Parasitoid and Parasitization of Plutella xylostella (L. (Lepidoptera: Yponomeutidae in South Sumatera

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SITI HERLINDA

2005-12-01

Full Text Available Surveys from May 2003 to January 2004 in South Sumatera were conducted to determine parasitoid attacking Plutella xylostella (L. and to estimate P. xylostella parasitization by the parasitoids. The eggs and the larvae of P. xylostella were collected from brassicaceous crops, i.e. mustard, Indian mustard, and cabbage. Six parasitoids found were Trichogrammatoidea cojuangcoi Nagaraja (Hymenoptera: Trichogrammatidae, Cotesia plutellae (Kurdj. (Hymenoptera: Braconidae, Diadegma semiclausum Hellen (Hymenoptera: Ichneumonidae, Oomyzus sokolowskii (Kurdj. (Hymenoptera: Eulophidae, Tetrastichus (Hymenoptera: Eulophidae, and a ceraphronid wasp (unidentified species. Trichogrammatoidea cojuangcoi parasitized P. xylostella eggs, however, the others parasitized the larvae except the ceraphronid wasp. In South Sumatera, the ceraphronid wasp was reported for the first time parasitizing D. semiclausum pupae, and its parasitization reached 6.2%. Oomyzus sokolowskii and Tetrastichus were found in this area for the first time, as well. In the highland, D. semiclausum was the most abundant compared to the others where its parasitization reached 79.2%. In the lowland P. xylostella larvae was mainly attacked by C. plutellae with the parasitization reaching 64.9%. In the dry and rainy seasons, the parasitization was mainly exerted by T. cojuangcoi (77.0% and D. semiclausum (79.2%.

Efficiency of vibrational sounding in parasitoid host location depends on substrate density.

Science.gov (United States)

Fischer, S; Samietz, J; Dorn, S

2003-10-01

Parasitoids of concealed hosts have to drill through a substrate with their ovipositor for successful parasitization. Hymenopteran species in this drill-and-sting guild locate immobile pupal hosts by vibrational sounding, i.e., echolocation on solid substrate. Although this host location strategy is assumed to be common among the Orussidae and Ichneumonidae there is no information yet whether it is adapted to characteristics of the host microhabitat. This study examined the effect of substrate density on responsiveness and host location efficiency in two pupal parasitoids, Pimpla turionellae and Xanthopimpla stemmator (Hymenoptera: Ichneumonidae), with different host-niche specialization and corresponding ovipositor morphology. Location and frequency of ovipositor insertions were scored on cylindrical plant stem models of various densities. Substrate density had a significant negative effect on responsiveness, number of ovipositor insertions, and host location precision in both species. The more niche-specific species X. stemmator showed a higher host location precision and insertion activity. We could show that vibrational sounding is obviously adapted to the host microhabitat of the parasitoid species using this host location strategy. We suggest the attenuation of pulses during vibrational sounding as the energetically costly limiting factor for this adaptation.

Nuclear magnetic resonance microscopy of the development of the parasitoid wasp Venturia canescens within its host moth Plodia interpunctella.

Science.gov (United States)

Chudek, J A; Crook, A M; Hubbard, S F; Hunter, G

1996-01-01

Nuclear magnetic resonance microscopy was used to image the parasitoid wasp Venturia canescens (Hymenoptera: Ichneumonidae) within larval and pupal instars of its host, the Indian meal moth, Plodia interpunctella (Lepidoptera: Pyralidae). The images were obtained using gradient-echo and chemical shift selective pulse sequences and clearly showed the location and shapes of the parasitoid as it developed from the L1 larva to a pupal stage within the host. The digestive, nervous, and tracheal systems of the host were identified and changes were observed as the host underwent metamorphosis. Destruction of the host tissues by the parasitoid was visible. It was found that the parasitoid first ate the fat body and digestive system of the host, allowing the host to continue to grow, and only progressed to the vital organs when its own development had neared pupation.

Analysis of Genetic Variation across the Encapsidated Genome of Microplitis demolitor Bracovirus in Parasitoid Wasps.

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Gaelen R Burke

Full Text Available Insect parasitoids must complete part of their life cycle within or on another insect, ultimately resulting in the death of the host insect. One group of parasitoid wasps, the 'microgastroid complex' (Hymenoptera: Braconidae, engage in an association with beneficial symbiotic viruses that are essential for successful parasitism of hosts. These viruses, known as Bracoviruses, persist in an integrated form in the wasp genome, and activate to replicate in wasp ovaries during development to ultimately be delivered into host insects during parasitism. The lethal nature of host-parasitoid interactions, combined with the involvement of viruses in mediating these interactions, has led to the hypothesis that Bracoviruses are engaged in an arms race with hosts, resulting in recurrent adaptation in viral (and host genes. Deep sequencing was employed to characterize sequence variation across the encapsidated Bracovirus genome within laboratory and field populations of the parasitoid wasp species Microplitis demolitor. Contrary to expectations, there was a paucity of evidence for positive directional selection among virulence genes, which generally exhibited signatures of purifying selection. These data suggest that the dynamics of host-parasite interactions may not result in recurrent rounds of adaptation, and that adaptation may be more variable in time than previously expected.

The landscape context of cereal aphid–parasitoid interactions

Science.gov (United States)

Thies, Carsten; Roschewitz, Indra; Tscharntke, Teja

2005-01-01

Analyses at multiple spatial scales may show how important ecosystem services such as biological control are determined by processes acting on the landscape scale. We examined cereal aphid–parasitoid interactions in wheat fields in agricultural landscapes differing in structural complexity (32–100% arable land). Complex landscapes were associated with increased aphid mortality resulting from parasitism, but also with higher aphid colonization, thereby counterbalancing possible biological control by parasitoids and lastly resulting in similar aphid densities across landscapes. Thus, undisturbed perennial habitats appeared to enhance both pests and natural enemies. Analyses at multiple spatial scales (landscape sectors of 0.5–6 km diameter) showed that correlations between parasitism and percentage of arable land were significant at scales of 0.5–2 km, whereas aphid densities responded to percentage of arable land at scales of 1–6 km diameter. Hence, the higher trophic level populations appeared to be determined by smaller landscape sectors owing to dispersal limitation, showing the ‘functional spatial scale’ for species-specific landscape management. PMID:15695212

Long-distance assessment of patch profitability through volatile infochemicals by the parasitoids Cotesia glomerata and C. rubecula (Hymenoptera: Braconidae).

NARCIS (Netherlands)

Geervliet, J.B.F.; Ariens, S.; Dicke, M.; Vet, L.E.M.

1998-01-01

Using two closely related larval parasitoids (Cotesiaspp.) ofPieriscaterpillars we tested the hypothesis that parasitoids are capable of assessing patch profitability from a distance by showing differential responses to odors from plants infested with different host densities. We furthermore tested

Relationship between oviposition, virulence gene expression and parasitism success in Cotesia typhae nov. sp. parasitoid strains.

Science.gov (United States)

Benoist, R; Chantre, C; Capdevielle-Dulac, C; Bodet, M; Mougel, F; Calatayud, P A; Dupas, S; Huguet, E; Jeannette, R; Obonyo, J; Odorico, C; Silvain, J F; Le Ru, B; Kaiser, L

2017-12-01

Studying mechanisms that drive host adaptation in parasitoids is crucial for the efficient use of parasitoids in biocontrol programs. Cotesia typhae nov. sp. (Fernández-Triana) (Hymenoptera: Braconidae) is a newly described parasitoid of the Mediterranean corn borer Sesamia nonagrioides (Lefebvre) (Lepidoptera: Noctuidae). Braconidae are known for their domesticated bracovirus, which is injected with eggs in the host larva to overcome its resistance. In this context, we compared reproductive success traits of four Kenyan strains of C. typhae on a French and a Kenyan populations of its host. Differences were found between the four strains and the two most contrasted ones were studied more thoroughly on the French host population. Parasitoid offspring size was correlated with parasitism success and the expression of bracovirus virulence genes (CrV1 and Cystatin) in the host larva after parasitism. Hybrids between these two parasitoid strains showed phenotype and gene expression profiles similar to the most successful parental strain, suggesting the involvement of dominant alleles in the reproductive traits. Ovary dissections revealed that the most successful strain injected more eggs in a single host larva than the less successful one, despite an equal initial ovocyte number in ovaries. It can be expected that the amount of viral particles increase with the number of eggs injected. The ability to bypass the resistance of the allopatric host may in consequence be related to the oviposition behaviour (eggs allocation). The influence of the number of injected eggs on parasitism success and on virulence gene expression was evaluated by oviposition interruption experiments.

Primary and secondary parasitoids (Hymenoptera) of aphids (Hemiptera: Aphididae) on blueberry and other Vaccinium in the Pacific Northwest.

Science.gov (United States)

Raworth, D A; Pike, K S; Tanigoshi, L K; Mathur, S; Graf, G

2008-04-01

Blueberry scorch virus, a commercially important Carlavirus in highbush blueberry, Vaccinium corymbosum L., is vectored by aphids (Hemiptera: Aphididae). We surveyed the aphids, primary parasitoids (Hymenoptera: Aphelinidae, Braconidae), and associated secondary parasitoids (Hymenoptera: Charipidae, Megaspilidae, Pteromalidae) on highbush blueberry and other Vaccinium in the Pacific Northwest from 1995 to 2006, with samples concentrated in 2005 and 2006, to lay the groundwork for augmentative biological control. Ericaphis fimbriata (Richards) was the principal aphid. The dominant parasitoid species were Praon unicum Smith, Aphidius n. sp., A. sp., and Aphidius ervi Haliday. Their frequency in relation to the other primary parasitoids varied significantly with geographical area; P. unicum dominated the frequency distribution in southwestern British Columbia, A. n. sp., west of the Cascades, and A. sp. and A. ervi east of the Cascades. Among the secondary parasitoids, pteromalids dominated, and their frequency in relation to the other secondary parasitoids was lowest in southwestern British Columbia. The parasitization rate for P. unicum and A. n. sp. in southwestern British Columbia increased from May or June to a maximum of 0.080 +/- 0.024 and 0.090 +/- 0.084 (SD), respectively, in late July or early August. P. unicum emerged in the spring 4 wk before A. n. sp. The parasitization rate for P. unicum was lower in conventional than organic fields. Whereas aphid density increased monotonically, P. unicum had two spring peaks. A simulation model showed that these peaks could reflect discrete generations. Releases of insectary-reared P. unicum at 150 or 450 DD above 5.6 degrees C, summing from 1 January, may effectively augment the natural spring populations by creating overlapping generations.

First foreign exploration for asian parasitoids of Drosophila suzukii

Science.gov (United States)

The invasive spotted wing drosophila, Drosophila suzukii Matsumura (Dipt.: Drosophilidae), is a native of East Asia and is now widely established in North America and Europe, where it is a serious pest of small and stone fruit crops. The lack of effective indigenous parasitoids of D. suzukii in the ...

Host availability affects the interaction between pupal parasitoid Coptera haywardi (Hymenoptera: Diiapridae) and larval-pupal parasitoid Diachasmimorpha longicaudata (Hymenoptera: Braconidae).

Science.gov (United States)

Montoya, P; Gálvez, C; Díaz-Fleischer, F

2018-02-12

The use of multiple species in biological control programmes is controversial when interactions among them are not fully understood. We determined the response of the pupal parasitoid Coptera haywardi (Oglobin) to different availability of Anastrepha ludens (Loew) pupae previously parasitized or not by larval-pupal Diachasmimorpha longicaudata (Ashmead). The two types of pupae were exposed at different ages and proportions to different numbers of C. haywardi females for 48 h. The performance of C. haywardi adults emerging from parasitized and unparasitized pupae was measured. Coptera haywardi prefers to attack unparasitized A. ludens pupae rather than pupae parasitized by D. longicaudata. However, when the availability of unparasitized pupae was low or the number of foraging females was high, C. haywardi competed against early immature stages of the D. longicaudata, or hyperparasitized, feeding directly on the advanced-immature developmental stages of the early acting species. Adults of C. haywardi emerging as hyperparasitoids were no different in size, fecundity and longevity from those emerging as primary parasitoids. Our data suggest that simultaneous use of these species in augmentative biological control projects may be feasible but should be carefully planned in order to avoid any detrimental effect of its interaction.

The herbivore-induced plant volatile methyl salicylate negatively affects attraction of the parasitoid Diadegma semiclausum.

Science.gov (United States)

Snoeren, Tjeerd A L; Mumm, Roland; Poelman, Erik H; Yang, Yue; Pichersky, Eran; Dicke, Marcel

2010-05-01

The indirect defense mechanisms of plants comprise the production of herbivore-induced plant volatiles that can attract natural enemies of plant attackers. One of the often emitted compounds after herbivory is methyl salicylate (MeSA). Here, we studied the importance of this caterpillar-induced compound in the attraction of the parasitoid wasp Diadegma semiclausum by using a mutant Arabidopsis line. Pieris rapae infested AtBSMT1-KO mutant Arabidopsis plants, compromised in the biosynthesis of MeSA, were more attractive to parasitoids than infested wild-type plants. This suggests that the presence of MeSA has negative effects on parasitoid host-finding behavior when exposed to wild-type production of herbivore-induced Arabidopsis volatiles. Furthermore, in line with this, we recorded a positive correlation between MeSA dose and repellence of D. semiclausum when supplementing the headspace of caterpillar-infested AtBSMT1-KO plants with synthetic MeSA.

Interspecific competition between Diadegma semiclausum Hellen and Diadegma mollipla (Holmgren), parasitoids of the diamondback moth, Plutella xylostella (L), feeding on a new host plant.

Science.gov (United States)

Rossbach, A; Löhr, B; Vidal, S

2008-04-01

Interspecific competition between an introduced parasitoid species aimed at controlling a herbivorous pest species and a native parasitoid parasitising the same host may influence the success of classical biological control programmes. In Kenya, interspecific competition between an introduced and a local parasitoid on two diamondback moth populations (DBM, Plutella xylostella) was investigated on two different host plants. We tested simultaneous and delayed competition of the local parasitoid Diadegma mollipla Holmgren and its exotic congenus D. semiclausum Hellen on a newly aquired DBM host plant (snowpea) in the laboratory. Under simultaneous competition, D. mollipla produced more progeny than D. semiclausum on snowpea. A head start of D. Mollipla, of four and eight hours before its congenus was introduced, resulted in a similar number of progeny of both species. In delayed competition (time intervals of 24 h, 48 h and 72 h), progeny production was similar for both parasitoids when the time interval was 24 h, irrespective of which species parasitized first. More progeny was produced by the species which attacked first, when the time interval was greater than 24 h, although it was only significant at 72 h. Competitive abilites of both parasitoids on the new host plant differed largely between laboratory and semi-field conditions. The influence of two host plants (snowpea and cabbage) on competition was studied in the greenhouse with different host and parasitoid densities. Parasitism levels of D. semiclausum were significantly higher than those of D. mollipla, regardless of host plant, host and parasitoid densities, but progeny production of D. mollipla on snowpea was still slightly higher than on cabbage. As compared to the confinement of parasitoids and larvae to small containers, D. mollipla parasitized very few larvae in the cages. Competitive ability of the two parasitoid species tested was influenced both by the density of the searching females and by

Dietary sugars and proline influence biological parameters of adult Trissolcus grandis, an egg parasitoid of Sunn pest, Eurygaster integriceps

NARCIS (Netherlands)

Hajirajabi, Nafiseh; Fazel, Morteza Movahedi; Harvey, Jeffrey A.; Arbab, Abbass; Asgari, Shahriar

Parasitoids are important natural enemies that are used in the biological control of insect herbivore pests. The egg parasitoid Trissolcus grandis Thompson (Hym. Scelionidae) is a major enemy of the Sunn pest, Eurygaster integriceps Puton (Hem. Scutelleridae), which in turn is one of the most

Parasitoids associated with the black scale Saissetia oleae(Olivier (Hemiptera: Coccidae in olive trees in Minas Gerais State, Brazil

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Ernesto Prado

2015-10-01

Full Text Available Black scale, Saissetia oleae (Olivier (Hemiptera: Coccidae is an important pest of olive trees (Olea europaea L. that requires the use insecticides for its control. Parasitoids are important regulating agents of this pest, but currently, no information on its complex of natural enemies and their impact on black scale in Brazilian conditions exists. This study focused on identifying parasitoid wasps that were associated with the black scale on olive trees to establish their relative abundance and rate of parasitism. Samplings were maintained in an olive orchard located in Maria da Fe, south of the state of Minas Gerais, Brazil, and infested branches were stored in emergence containers to recover parasitoids. Another group was kept in Flanders batteries to evaluate the rate of parasitism in approximately 100 scales. Sixteen parasitoid species were collected during the sampling period, and the most common species were Coccophagus caridei (Brèthes (Hymenoptera: Aphelinidae, Diversinervus elegans Silvestri (Hymenoptera: Encyrtidae, and Mesopeltita truncatipennis (Waterston (Hymenoptera: Pteromalidae, the latter of which was most abundant and frequent. Parasitism ranged from 3 to 31% with peaks in summer and autumn. This level could be considered insufficient to hold the black scale under the economic injury level; however, these parasitoids should be preserved for contributions to population regulation.

Eco-toxicological risk and impact of pesticides on important parasitoids of cabbage butterflies in cruciferous ecosystem.

Science.gov (United States)

Firake, D M; Thubru, D P; Behere, G T

2017-02-01

Eco-toxicological risk and impact of pesticides was estimated on three important parasitoids of butterflies viz., Hyposoter ebeninus, Cotesia glomerata and Pteromalus puparum. Four commonly used pesticides were evaluated using standard protocol (of IOBC/WPRS-group). In laboratory tests, the survival of the female wasps decreased significantly on fresh contact and ingestion of deltamethrin, spinosad and azadirachtin; whereas Bacillus thuringiensis var kurstaki (Btk) was found harmless pesticide. Under semi-field conditions, parasitoid mortality decreased significantly on fresh contact with the pesticides. Although, at 72 h after treatment, spinosad and deltamethrin were found harmful (Class-IV) and azadirachtin was moderately harmful (Class-III), whereas Btk was harmless (Class-I). Furthermore, 15-day-old residues of pesticides (except deltamethrin) were harmless to all parasitoid species under semi-field conditions. Notably, adult emergence and pupal duration in pesticide-treated cocoons were not significantly affected; however, their survival decreased after emergence except in Btk. The contact and oral toxicity trends of the pesticides were almost similar for three species of parasitoid females and pupae; however little variability was observed in toxicity to the host caterpillars parasitized by H. ebeninus (HCPHE) and C. glomerata (HCPCG). In semi-field tests, fresh residues of all the pesticides were harmful to HCPHE and HCPCG. However, action of Btk was slightly delayed and toxicity was rather low for HCPCG. In 15-day-old residues, deltamethrin and azadirachtin were slightly harmful to the parasitized caterpillars, whereas those of Btk and spinosad were harmless. Since, Btk appeared to be safe for parasitoids; it could be used for managing cabbage butterflies in brassicaceous crops. Copyright © 2016 Elsevier Ltd. All rights reserved.

Insects Can Count: Sensory Basis of Host Discrimination in Parasitoid Wasps Revealed.

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Sara Ruschioni

Full Text Available The solitary parasitoid Leptopilina heterotoma is one of the best studied organisms concerning the ecology, behaviour and physiology of host discrimination. Behavioural evidence shows that L. heterotoma uses its ovipositor to discriminate not only between parasitized and unparasitized Drosophila melanogaster larvae, but also to discriminate between hosts with different numbers of parasitoid eggs. The existing knowledge about how and when the parasitoid marks the host motivated us to unravel the chemosensory basis of host discrimination by L. heterotoma that allows it to choose the "best" host available. In this paper we report on electrophysiological recordings of multi-neural responses from the single taste sensillum on the tip of the unpaired ovipositor valve. We stimulated this sensillum with haemolymph of unparasitized, one-time-parasitized and two-times-parasitized Drosophila larvae. We demonstrate for the first time that quantitative characteristics of the neural responses to these haemolymph samples differed significantly, implying that host discrimination is encoded by taste receptor neurons in the multi-neuron coeloconic ovipositor sensillum. The activity of three of the six neurons present in the sensillum suffices for host discrimination and support the hypothesis that L. heterotoma females employ an ensemble code of parasitization status of the host.

Linking spatial processes to life-history evolution of insect parasitoids

NARCIS (Netherlands)

Hoffmeister, T.S.; Roitberg, B.D.; Vet, L.E.M.

2005-01-01

Understanding the evolutionary transition from solitary to group living in animals is a profound challenge to evolutionary ecologists. A special case is found in insect parasitoids, where a tolerant gregarious larval lifestyle evolved from an intolerant solitary ancestor. The conditions for this

Habitat eradication and cropland intensification may reduce parasitoid diversity and natural pest control services in annual crop fields

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Deborah K. Letourneau

2015-10-01

Full Text Available Abstract California’s central coast differs from many agricultural areas in the U.S., which feature large tracts of monoculture production fields and relatively simple landscapes. Known as the nations salad bowl, and producing up to 90% of U.S. production of lettuces, broccoli and Brussels sprouts, this region is a mosaic of fresh vegetable fields, coastal meadow, chaparral shrubs, riparian and woodland habitat. We tested for relationships between the percent cover of crops, riparian and other natural landscape vegetation and the species richness of parasitic wasps and flies foraging in crops, such as broccoli, kale and cauliflower, and interpreted our results with respect to the decrease in natural habitat and increase in cropland cover prompted by a local microbial contamination event in 2006. Our key results are that: (1 as cropland cover in the landscape increased, fewer species of parasitoids were captured in the crop field, (2 parasitoid richness overall was positively associated with the amount of riparian and other natural vegetation in the surrounding 500m, (3 different groups of parasitoids were associated with unique types of natural vegetation, and (4 parasitism rates of sentinel cabbage aphid and cabbage looper pests were correlated with landscape vegetation features according to which parasitoids caused the mortality. Although individual species of parasitoids may thrive in landscapes that are predominantly short season crops, the robust associations found in this study across specialist and generalist parasitoids and different taxa (tachinid flies, ichneumon wasps, braconid wasps shows that recent food safety practices targeting removal of natural vegetation around vegetable fields in an attempt to eliminate wildlife may harm natural enemy communities and reduce ecosystem services. We argue that enhancing biological diversity is a key goal for transforming agroecosystems for future productivity, sustainability and public health.

The spatial distribution of Hymenoptera parasitoids in a forest reserve in Central Amazonia, Manaus, AM, Brazil

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RB. Querino

Full Text Available Parasitoids are of great importance to forest ecosystems due to their ecological role in the regulation of the population of other insects. The species richness and abundance of parasitoids in the forest canopy and understory, both on the borders and in the interior of a tropical forest reserve in Central Amazonia were investigated. For a 12-month period, specimen collections were made every 15 days from suspended traps placed in the forest canopy and in the understory strata, both on the border and in the interior of forest areas. A total of 12,835 Hymenoptera parasitoids from 23 families were acquired. Braconidae, Diapriidae, Mymaridae, Eulophidae, and Scelionidae were the most represented in the area and strata samples. The results indicate that there were no significant differences in the species richness or abundance of Hymenoptera between the forest borders and the inner forest. The data does show that the presence of Hymenoptera is significantly greater in the understory in both the border and interior areas than in the canopy (vertical stratification. Aphelinidae and Ceraphronidae were significantly associated with the inner forest, while the other seven families with the border of the reserve. The abundance of Hymenoptera parasitoids presented seasonal variations during the year related to the rainy and dry seasons.

Investigation of the lethal and behavioral effects of commercial insecticides on the parasitoid wasp Copidosoma truncatellum.

Science.gov (United States)

Ramos, Rodrigo S; de Araújo, Vitor C R; Pereira, Renata R; Martins, Júlio C; Queiroz, Obiratanea S; Silva, Ricardo S; Picanço, Marcelo C

2018-01-01

Copidosoma truncatellum (Hymenoptera: Encyrtidae) is an important parasitoid wasp of the soybean looper, Chrysodeixis includens, but its effectiveness can be severely curtailed by the application of certain insecticides. Therefore, to identify insecticides that are potentially compatible with C. truncatellum, the lethal and behavioral effects of nine chemicals used to control the soybean looper were evaluated for their toxicity to the wasp. Chlorantraniliprole, chlorfenapyr, flubendiamide, and indoxacarb were the least toxic insecticides to the parasitoid, resulting in mortalities of less than 25%. In contrast, cartap, deltamethrin, and methomyl caused 100% mortality, and acephate and spinosad caused 76% and 78% mortality, respectively. At least one of the detoxifying enzymes (monooxygenase, glutathione S-transferase, and/or esterases) may be involved in the mechanisms underlying the selectivity of chlorantraniliprole, chlorfenapyr, flubendiamide, and indoxacarb for the parasitoid based on the results for the insecticide plus synergist treatment. Changes in the behavioral patterns (walking time and resting time) of the parasitoid were found with exposure to acephate, flubendiamide, indoxacarb and methomyl, but behavioral avoidance was not observed. Our results indicate that the insecticides chlorantraniliprole and chlorfenapyr are the most suitable for inclusion in integrated pest management strategies for the control of C. includens. Copyright © 2017 Elsevier Ltd. All rights reserved.

Evolutionary ecology of the interactions between aphids and their parasitoids.

Science.gov (United States)

Le Ralec, Anne; Anselme, Caroline; Outreman, Yannick; Poirié, Marylène; van Baaren, Joan; Le Lann, Cécile; van Alphen, Jacques J-M

2010-01-01

Many organisms, including entomopathogenous fungi, predators or parasites, use aphids as ressources. Parasites of aphids are mostly endoparasitoid insects, i.e. insects which lay eggs inside the body of an other insect which will die as a result of their development. In this article, we review the consequences of the numerous pecularities of aphid biology and ecology for their endoparasitoids, notably the Aphidiinae (Hymenoptera: Braconidae). We first examine the various mechanisms used by aphids for defence against these enemies. We then explore the strategies used by aphidiine parasitoids to exploit their aphid hosts. Finally, we consider the responses of both aphids and parasitoids to ecological constraints induced by seasonal cycles and to environmental variations linked to host plants and climate. The fundamental and applied interest of studying these organisms is discussed. Copyright 2010 Académie des sciences. Published by Elsevier SAS. All rights reserved.

Numerical relationships of the Solidago altissima stem gall insect-parasitoid guild food chain.

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Abrahamson, Warren G; Armbruster, Paulette O; Maddox, G David

1983-06-01

The field site conditions (soil pH, soil moisture, soil nutrient availability, etc.) and abundances of Solidago altissima (often included in S. canadensis sensu lato), three S. altissima specific stem gall formers, and the parasitepredator guilds for two of the three gall insects were investigated. It was found that S. altissima is tolerant of a wide range of site conditions. Herbivore (stem gall insects) occurrences were positively correlated with plant occurrence, in a linear fashion. However, there was no disproportionate increase in stem gall insect densities with plant density as might be predicted by the resource concentration hypothesis. Parasitoid guilds were exploiting stem gall insect populations over a wide range of occurrence, but were under-utilizing fields of higher herbivore occurrences. Path analysis showed a high degree of predictability in the causal models, with all but 14% of the ball gall parasitoid guild and all but 43% of the elliptical gall parasitoid guild occurrences explained by the direct influences of stem gall insect occurrence and the indirect influences of goldenrod occurrence and site conditions. The numerical relations of this three trophic level system suggest a well-integrated and well-controlled food chain.

Plant strengtheners enhance parasitoid attraction to herbivore-damaged cotton via qualitative and quantitative changes in induced volatiles.

Science.gov (United States)

Sobhy, Islam S; Erb, Matthias; Turlings, Ted C J

2015-05-01

Herbivore-damaged plants release a blend of volatile organic compounds (VOCs) that differs from undamaged plants. These induced changes are known to attract the natural enemies of the herbivores and therefore are expected to be important determinants of the effectiveness of biological control in agriculture. One way of boosting this phenomenon is the application of plant strengtheners, which has been shown to enhance parasitoid attraction in maize. It is unclear whether this is also the case for other important crops. The plant strengtheners BTH [benzo (1,2,3) thiadiazole-7-carbothioic acid S-methyl ester] and laminarin were applied to cotton plants, and the effects on volatile releases and the attraction of three hymenopteran parasitoids, Cotesia marginiventris, Campoletis sonorensis and Microplitis rufiventris, were studied. After treated and untreated plants were induced by real or simulated caterpillar feeding, it was found that BTH treatment increased the attraction of the parasitoids, whereas laminarin had no significant effect. BTH treatment selectively increased the release of two homoterpenes and reduced the emission of indole, the latter of which had been shown to interfere with parasitoid attraction in earlier studies. Canonical variate analyses of the data show that the parasitoid responses were dependent on the quality rather than the quantity of volatile emission in this tritrophic interaction. Overall, these results strengthen the emerging paradigm that induction of plant defences with chemical elicitors such as BTH could provide a sustainable and environmentally friendly strategy for biological control of pests by enhancing the attractiveness of cultivated plants to natural enemies of insect herbivores. © 2014 Society of Chemical Industry.

Lethal and sublethal effects of four essential oils on the egg parasitoids Trissolcus basalis.

Science.gov (United States)

Werdin González, Jorge Omar; Laumann, Raúl Alberto; da Silveira, Samantha; Moraes, Maria Carolina Blassioli; Borges, Miguel; Ferrero, Adriana Alicia

2013-07-01

The essential oils from leaves of Schinus molle var. areira, Aloysia citriodora, Origanum vulgare and Thymus vulgaris have showed potential as phytoinsecticides against the green stink bug, Nezara viridula. In this work were evaluated their toxicological and behavioral effects on the parasitoid Trissolcus basalis, a biological control agent of this pest insect. Essential oils were obtained via hydrodestillation from fresh leaves. Insecticide activity in T. basalis females was evaluated in direct contact and fumigation bioassays. Behavioral effects were evaluated in olfactometer bioassays. To evaluate the residual toxicity, females of the parasitoids were exposed to oil residues; in these insects, the sublethal effects were evaluated (potential parasitism and survivorship of immature stages). The essential oils from O. vulgare and T. vulgaris proved to be highly selective when used as fumigant and did not change parasitoid behavior. After one week, the residues of these oils were harmless and did not show sublethal effects against T. basalis. According with these results, essential oils have potential applications for the integrated management of N. viridula. Published by Elsevier Ltd.

[Dipteran parasitoidism on larvae of Caligo atreus (Lepidoptera: Nymphalidae) in Cartago, Costa Rica].

Science.gov (United States)

Calvo, Renin

2004-12-01

Parasitoids on larvae of Caligo atreus were studied at the Estación de Biologia Tropical in Rio Macho, Cartago, Costa Rica. (1 600 masl), from March through July 2000. Fifth instar larvae of C. atreus were placed on Heliconia tortuosa Griggs var. Red Twist (Heliconiaceae) host plants at a mean temperature of 16.7 degrees C. The parasitoids obtained belong to an unidentified species of the genus Winthemia (Diptera: Tachinidae). Most flies emerge some 40 days after the eggs were laid (maximum 68 days). They make an orifice on the upper ventral part of the lepidopteran pupa. Winthemia is used commercially as biological control of cotton and banana.

Aphid parasitoids that occur on wheat crops of Northeast of the Parana State with recovery of Aphidius rhopalosiphi in BrazilParasitoides de pulgões-do-trigo que ocorrem no Norte do estado do Paraná e recaptura de Aphidius rhopalosiphi no Brasil

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Adriano Thibes Hoshino

2012-02-01

Full Text Available Aphids (Hemiptera: Aphididae are the main pest of wheat (Hemiptera: Aphididae in several countries. In Brazil, the Biological Control of Wheat Aphids released millions of aphid parasitoids (Hymenoptera: Braconidae and Aphelinidae on wheat fields and in the present moment the chemical control is rarely necessary. However, since the 80’s few studies was carried out to evaluate the species established in Brazil. For this reason, the aim of this study was to record the species of aphid parasitoids that occur in wheat in the northern region of Parana state, Brazil. Four commercial wheat fields were investigated in the agricultural years of 2008 and 2009. The aphid parasitoids were captured with traps (Moericke and Malaise and aphid mummified were collected. In total, six species of parasitoids were found, Aphidius colemani, A. uzbekistanicus, A. ervi, Aphidius rhopalosiphi, Diaeretiella rapae e Lysiphlebus testaceipes. These results contribute with the register of three exotic species in Parana, and confirm the establishment of A. rhopalosiphi in the country. We emphasize the need for further studies in other regions of the country, as other species introduced also need to have their establishment confirmed.Os pulgões (Hemiptera: Aphididae são pragas de extrema importância em cereais de inverno no mundo todo. No Brasil, o programa Controle Biológico de Pulgões do Trigo liberou milhões de parasitoides (Hymenoptera: Braconidae e Aphelinidae nas áreas tritícolas, reduzindo expressivamente a população da praga, e atualmente raramente o controle químico se faz necessário. Entretanto, desde a década de 80 poucos trabalhos de campo tem sido realizados para verificar as espécies efetivamente estabelecidas no País. Por esta razão, este estudo objetivou registrar as espécies de parasitoides de pulgões ocorrentes em lavouras de trigo na região Norte no Paraná. O trabalho foi realizado em quatro áreas comerciais de trigo, durante as safras

Terpenoid biosynthesis in Arabidopsis attacked by caterpillars and aphids: effects of aphid density on the attraction of a caterpillar parasitoid.

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Kroes, Anneke; Weldegergis, Berhane T; Cappai, Francesco; Dicke, Marcel; van Loon, Joop J A

2017-12-01

One of the responses of plants to insect attack is the production of volatile organic compounds that mediate indirect defence of plants by attracting natural enemies of the attacking herbivores. Herbivore-induced plant volatiles (HIPVs) include terpenoids that play key roles in the attraction of natural enemies. Crosstalk between phytohormonal signalling pathways is well known to affect the regulation of plant defences, including the emission of HIPVs. Thus, simultaneous feeding on the same plant by caterpillars and aphids, can affect the attraction of parasitoids by the plant compared to single insect attack. The role of aphid density in the regulation of HIPV emission by plants under dual attack has not been studied previously. Here, we investigated the attraction of Diadegma semiclausum, a parasitoid of the Diamondback moth Plutella xylostella, to volatiles emitted by Arabidopsis thaliana plants, simultaneously attacked by host caterpillars, and by the non-host aphid Brevicoryne brassicae. Our study shows that the effect of aphid infestation on parasitoid attraction is influenced by the density of the aphids. Biosynthesis and emission of (E,E)-α-farnesene could be linked to the observed preference of D. semiclausum parasitoids for the HIPV blend emitted by plants dually infested by caterpillars and aphids at a high density compared to dually infested plants with a low aphid density. Parasitoids such as D. semiclausum are important enemies of herbivorous insects and a better understanding of how plants express indirect defence mechanisms in response to multiple insect attack will provide important knowledge on plant-herbivore-parasitoid interactions under multiple stress conditions.

Effects of dietary nicotine on the development of an insect herbivore, its parasitoid and secondary hyperparasitoid over four trophic levels

NARCIS (Netherlands)

Harvey, J.A.; Dam, van N.M.; Witjes, L.M.A.; Soler, R.; Gols, R.

2007-01-01

1. Allelochemicals in herbivore diet are known to affect the development of higher trophic levels, such as parasitoids and predators. 2. This study examines how differing levels of nicotine affects the development of a herbivore, its parasitoid and secondary hyperparasitoid over four trophic levels.

Effects of soybean resistance on variability in life history traits of the higher trophic level parasitoid Meteorus pulchricornis (Hymenoptera: Braconidae).

Science.gov (United States)

Li, X; Li, B; Xing, G; Meng, L

2017-02-01

To extrapolate the influence of plant cultivars varying in resistance levels to hosts on parasitoid life history traits, we estimated variation in parasitoid developmental and reproductive performances as a function of resistance in soybean cultivars, which were randomly chosen from a line of resistant genotypes. Our study showed that the parasitoid Meteorus pulchricornis varied widely in offspring survival and lifetime fecundity, but varied slightly in development time and adult body size, in response to the soybean cultivars that varied in resistance to the host Spodoptera litura. Furthermore, the variability in survival and lifetime fecundity was different between attacking the 2nd and the 4th instar host larvae, varying more in survival but less in lifetime fecundity when attacking the 4th than 2nd instar larvae. Our study provides further evidence supporting that plant resistance to herbivorous hosts have variable effects on different life history traits of higher trophic level parasitoids.

Duration of plant damage by host larvae affects attraction of two parasitoid species (Microplitis croceipes and Cotesia marginiventris) to cotton: implications for interspecific competition.

Science.gov (United States)

Morawo, Tolulope; Fadamiro, Henry

2014-12-01

Volatile organic compounds (VOCs) released by herbivore-damaged plants can guide parasitoids to their hosts. The quantity and quality of VOC blends emitted by plants may be affected by the duration of plant damage by herbivores, which could have potential ramifications on the recruitment of competing parasitoids. We used two parasitoid species, Microplitis croceipes and Cotesia marginiventris (Hymenoptera: Braconidae), to address the question of whether duration of plant damage affects parasitoid use of plant VOCs for host location. Both wasp species are larval endoparasitoids of Heliothis virescens (Lepidoptera: Noctuidae), an important pest of cotton. Attraction of the two parasitoid species to odors emitted by undamaged (UD), fresh (6 h infestation) damage (FD), and old (24 h infestation) damage (OD) cotton plants infested by H. virescens larvae was investigated using a headspace volatile collection system coupled with four-choice olfactometer bioassay. Both sexes of M. croceipes showed a preference for FD- and OD-plant odors over UD-plants. On the other hand, more C. marginiventris females were attracted to UD- and FD-plants than to OD-plants. GC/MS analyses showed qualitative and quantitative differences in the VOC profiles of UD, FD, and OD-plants, which may explain the observed preferences of the parasitoids. These results suggest a temporal partitioning in the recruitment of M. croceipes and C. marginiventris to H. virescens-damaged cotton, and may have potential implications for interspecific competition between the two parasitoid species.

Advances and perspectives in the mass rearing of fruit fly parasitoids in Mexico

Energy Technology Data Exchange (ETDEWEB)

Cancino, Jorge; Montoya, Pablo [Secretaria de Agricultura, Ganaderia, Desarrollo Rural, Pesca y Alimentacion (DGSV/SENASICA/SAGARPA), Chiapas (Mexico). Servicio Nacional de Sanidad, Inocuidad y Calidad Agroalimentaria. Programa Moscamed-Moscafrut

2006-07-01

Biological control by augmentation is applied in Mexico as part of an integrated pest management program against native fruit flies of the genus Anastrepha Schiner. The exotic parasitoid Diachasmimorpha longicaudata has been the most important species used within this context. A program for the mass rearing of 50 million parasitized pupa per week has been established in southeast Mexico, and these are released into the field according to a yearly national plan based on industry requirements. In order to reduce costs and optimize procedures, important advances have been made in the technology for mass production, including an increase in the weight of host larvae (24 mg), changes in the management of host exposition, improvements in the management of environmental conditions, suitability in time and motions are the main areas addressed. Furthermore, a quality control program is routinely applied, and the key parameters under constant evaluation are: 1) weight and volume of host larvae, 2) host mortality after exposure, 3) weight and volume of pupae, and 4) percent parasitoid viability and percent emergence. Good performance in these parameters produces adults with adequate longevity and fecundity, high flight ability and good searching behavior. The introduced egg parasitoid Fopius arisanus and the native pupal parasitoid Coptera hawardi are being evaluated for use in the future as a complement to releases into the field of D. longicaudata. Manipulating host size and exposition time, the use of starting diet and suppressing host development by irradiation, have permitted the effective use of Anastrepha eggs as hosts for the rearing of F. arisanus. Further achievements in the mass rearing of C. haywardi (e.g., the suppression of unparasitized hosts after irradiation), could give us the opportunity to employ new options to reinforce the augmentative biological control of Anastrepha fruit flies in Mexico. (author)

Variation in the diversity and richness of parasitoid wasps based on sampling effort.

Science.gov (United States)

Saunders, Thomas E; Ward, Darren F

2018-01-01

Parasitoid wasps are a mega-diverse, ecologically dominant, but poorly studied component of global biodiversity. In order to maximise the efficiency and reduce the cost of their collection, the application of optimal sampling techniques is necessary. Two sites in Auckland, New Zealand were sampled intensively to determine the relationship between sampling effort and observed species richness of parasitoid wasps from the family Ichneumonidae. Twenty traps were deployed at each site at three different times over the austral summer period, resulting in a total sampling effort of 840 Malaise-trap-days. Rarefaction techniques and non-parametric estimators were used to predict species richness and to evaluate the variation and completeness of sampling. Despite an intensive Malaise-trapping regime over the summer period, no asymptote of species richness was reached. At best, sampling captured two-thirds of parasitoid wasp species present. The estimated total number of species present depended on the month of sampling and the statistical estimator used. Consequently, the use of fewer traps would have caught only a small proportion of all species (one trap 7-21%; two traps 13-32%), and many traps contributed little to the overall number of individuals caught. However, variation in the catch of individual Malaise traps was not explained by seasonal turnover of species, vegetation or environmental conditions surrounding the trap, or distance of traps to one another. Overall the results demonstrate that even with an intense sampling effort the community is incompletely sampled. The use of only a few traps and/or for very short periods severely limits the estimates of richness because (i) fewer individuals are caught leading to a greater number of singletons; and (ii) the considerable variation of individual traps means some traps will contribute few or no individuals. Understanding how sampling effort affects the richness and diversity of parasitoid wasps is a useful

Advances and perspectives in the mass rearing of fruit fly parasitoids in Mexico

International Nuclear Information System (INIS)

Cancino, Jorge; Montoya, Pablo

2006-01-01

Biological control by augmentation is applied in Mexico as part of an integrated pest management program against native fruit flies of the genus Anastrepha Schiner. The exotic parasitoid Diachasmimorpha longicaudata has been the most important species used within this context. A program for the mass rearing of 50 million parasitized pupa per week has been established in southeast Mexico, and these are released into the field according to a yearly national plan based on industry requirements. In order to reduce costs and optimize procedures, important advances have been made in the technology for mass production, including an increase in the weight of host larvae (24 mg), changes in the management of host exposition, improvements in the management of environmental conditions, suitability in time and motions are the main areas addressed. Furthermore, a quality control program is routinely applied, and the key parameters under constant evaluation are: 1) weight and volume of host larvae, 2) host mortality after exposure, 3) weight and volume of pupae, and 4) percent parasitoid viability and percent emergence. Good performance in these parameters produces adults with adequate longevity and fecundity, high flight ability and good searching behavior. The introduced egg parasitoid Fopius arisanus and the native pupal parasitoid Coptera hawardi are being evaluated for use in the future as a complement to releases into the field of D. longicaudata. Manipulating host size and exposition time, the use of starting diet and suppressing host development by irradiation, have permitted the effective use of Anastrepha eggs as hosts for the rearing of F. arisanus. Further achievements in the mass rearing of C. haywardi (e.g., the suppression of unparasitized hosts after irradiation), could give us the opportunity to employ new options to reinforce the augmentative biological control of Anastrepha fruit flies in Mexico. (author)

Botanical insecticides on Liriomyza huidobrensis Blanchard (Diptera: Agromyzidae and its parasitoids in string beans cultivated in a plastic greenhouse

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Sônia Thereza Bastos Dequech

2010-06-01

Full Text Available The string bean (Phaseolus vulgaris L. is Sul. Liriomyza huidobrensis (Dip.: Agromyzidae is one of the most important insect pests occurring in this culture. This research was conducted to evaluate the effect of aqueous extracts of plants and the commercial product DalNeem on L. huidobrensis and its parasitoids, as well as to analyse the population fluctuation of L. huidobrensis and parasitoids of this insect pest. The experiment was carried out on string beans cultivated in a greenhouse, where in each of the four central lines of culture, five plots were established with five plants per plot. The experimental design was random blocks with four replications. DalNeem was the treatment that best controlled L. huidobrensis. On the other hand, the treatments did not affect the parasitoids Chrysocharis bedius (Hym.: Eulophidae or Opius sp. (Hym.: Braconidae. In plants without the use of these treatments, the population of L. huidobrensis exhibited a sharp decline with the increase of the parasitoids C. bedius, Opius sp., Eucoilinae (Hym.: Figitidae and Diptera.

Manure Preferences and Postemergence Learning of Two Filth Fly Parasitoids, Spalangia cameroni and Muscidifurax raptor (Hymenoptera: Pteromalidae.

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Caitlin E Taylor

Full Text Available The efficiency of host-seeking behavior is crucial to the reproductive performance of female parasitoids. Initially, parasitoids may use chemical information garnered from the microhabitat in which they emerge to locate hosts. Spalangia cameroni and Muscidifurax raptor are commercially available parasitoids of filth flies. Postemergence exposure to a specific manure may provide a way to increase parasitism in specific microhabitats found at livestock facilities upon release. In this study, female parasitoids of both species were exposed to equine manure, bovine manure, or clean pupae. Females from each emergence exposure were tested in a two-choice arena (house fly hosts in bovine manure versus clean pupae, equine manure versus clean pupae, and equine manure versus bovine manure for progeny production. There was a detectable but small effect of postemergence exposure on S. cameroni, but it was not sufficient to reverse innate preferences. Females consistently produced more progeny in hosts found in any manure over clean pupae, and in equine manure over bovine manure. The effect of postemergence exposure on M. raptor was also detectable but small. Females produced equal numbers of progeny in bovine manure versus clean pupae, as opposed to preferring to oviposit in clean pupae as with all other treatments. Preferences by M. raptor were overall less marked than for S. cameroni; indeed most of the variability observed for this species did not result from the treatment design. Residual host mortality was also detectably altered by exposure in both species, but the effect was small. Thus, postemergence exposure did not consistently and effectively manipulate these parasitoids to producing progeny in different exposure manures, suggesting that microhabitat preferences are largely determined by other factors.

POTENTIAL IMPACT OF METARHIZIUM ANISOPLIAE ON THE DIAMONDBACK MOTH (LEPIDOPTERA: PLUTELLIDAE AND ITS PARASITOID DIADEGMA SEMICLAUSUM (HYMENOPTERA: ICHNEUMONIDAE

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Rosma Hasibuan, Nilly Christalia, F.X. Susilo1, and Nur Yasin .

2011-11-01

Full Text Available Potential Impact of Metarhizium anisopliae on the Diamondback Moth (Lepidoptera: Plutellidae and Its Parasitoid Diadegma semiclausum (Hymenoptera: Ichneumonidae.  Laboratory studies were conducted to evaluate the effect of the Metarhizium anisopliae against the diamondback moth, Plutella xylostella and its parasitoid, Diadegma  semiclausum. A completely randomized design consisted of 5 treatments (4 concentrations of conidial suspension: 5 x 104, 3.5 x 105, 2.5 x 106, 1.2 x 107 conidia/ml and control was used.  The results indicated that the mortality of P. xylostella larvae were significantly induced by the fungal treatments.  A significant reduction in pupation and adult emergence of P. xylostella was also detected in all treatments when compared with that in the control. The fungus might also result in a male-biased sex ratio of the surviving P. xylostella. When applied at a concentration of 1.2 x 107 conidia/ml, M.  anisopliae might significantly reduce the survival of the parasitoid, D. semiclausum. Thus, despite its potential as a biological control agent against P. xylostella, the entomomogenous fungus M. anisopliae was also detrimental to the larvae parasitoid D. semiclausum.

Sugar in Moderation: Variable Sugar Diets Affect Short-Term Parasitoid Behavior

Science.gov (United States)

The biological control potential of parasitic wasps in the field is expected to increase with provisioning of sugar sources, which increase longevity and replenish carbohydrate reserves. Apanteles aristoteliae Viereck is an important parasitoid of Argyrotaenia franciscana (Walsingham), the orange to...

Close-range host searching behavior of the stemborer parasitoids Cotesia sesamiae and Dentichasmias busseolae: influence of a non-host-plant Melinis minutiflora

NARCIS (Netherlands)

Gohole, L.S.; Overholt, W.A.; Khan, Z.R.; Vet, L.E.M.

2005-01-01

Studies were conducted on the host searching behavior of the larval parasitoid Cotesia sesamiae (Cameron) (Hymenoptera: Braconidae) and the pupal parasitoid Dentichasmias busseolae Heinrich (Hymenoptera: Ichneumonidae), both of which attack lepidopteran (Crambidae, Noctuidae) cereal stemborers. The

Close-range host searching behavior of the stemborer parasitoids Cotesia sesamiae and Dentichasmias busseolae: Influence of a non-host plant Melinis minutiflora

NARCIS (Netherlands)

Gohole, L.S.; Overholt, W.A.; Khan, Z.U.; Vet, L.E.M.

2005-01-01

Studies were conducted on the host searching behavior of the larval parasitoid Cotesia sesamiae (Cameron) (Hymenoptera: Braconidae) and the pupal parasitoid Dentichasmias busseolae Heinrich (Hymenoptera: Ichneumonidae), both of which attack lepidopteran (Crambidae, Noctuidae) cereal stemborers. The

Bee species-specific nesting material attracts a generalist parasitoid: implications for co-occurring bees in nest box enhancements.

Science.gov (United States)

Macivor, J Scott; Salehi, Baharak

2014-08-01

Artificial nests (e.g., nest boxes) for bees are increasingly being used to contribute to nesting habitat enhancement for bees that use preexisting cavities to provision brood. They usually incorporate additional nesting materials that vary by species. Cavity-nesting bees are susceptible to brood parasitoids that recognize their host(s) using visual and chemical cues. Understanding the range of cues that attract parasitoids to bee nests, including human-made analogues, is important if we wish to control parasitism and increase the potential value of artificial nests as habitat-enhancement strategies. In this study, we investigated the cues associated with the orientation of the generalist brood parasitoid Monodontomerus obscurus Westwood (Hymenoptera: Torymidae) to the nests of a common cavity-nesting resin bee Megachile campanulae (Robertson) (Megachilidae). The parasitoids were reared from previously infested M. campanulae brood cells and placed into choice trials where they were presented with pairs of different nest material cues. Among different materials tested, we found that Mo. obscurus was most attracted to fresh resin collected directly from Pinus strobus trees followed by previously used resin collected from the bee nest. The parasitoid also attacked other bee species in the same nest boxes, including those that do not use resin for nesting. Our findings suggest that M. campanulae could act as a magnet, drawing parasites away from other bee hosts co-occurring in nest boxes, or, as an attractant of Mo. obscurus to nest boxes, increasing attacks on co-occurring host bee species, potentially undermining bee diversity enhancement initiatives.

Plant pathogen-induced volatiles attract parasitoids to increase parasitism of an insect vector

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Xavier eMartini

2014-05-01

Full Text Available Interactions between plant pathogens and arthropods have been predominantly studied through the prism of herbivorous arthropods. Currently, little is known about the effect of plant pathogens on the third trophic level. This question is particularly interesting in cases where pathogens manipulate host phenotype to increase vector attraction and presumably increase their own proliferation. Indeed, a predator or a parasitoid of a vector may take advantage of this manipulated phenotype to increase its foraging performance. We explored the case of a bacterial pathogen, Candidatus Liberibacter asiaticus (Las, which modifies the odors released by its host plant (citrus trees to attract its vector, the psyllid Diaphorina citri. We found that the specialist parasitoid of D. citri, Tamarixia radiata, was attracted more toward Las-infected than uninfected plants. We demonstrated that this attractiveness was due to the release of methyl salicylate. Parasitization of D. citri nymphs on Las-infected plants was higher than on uninfected controls. Also, parasitization was higher on uninfected plants baited with methyl salicylate than on non-baited controls. This is the first report of a parasitoid ‘eavesdropping’ on a plant volatile induced by bacterial pathogen infection, which also increases effectiveness of host seeking behavior of its herbivorous vector.

Determination of Opiinae parasitoids (Hymenoptera: Braconidae) associated with crop infesting Bactrocera spp. (Diptera: Tephritidae) using COI and Cyt b sequences

Science.gov (United States)

Shariff, Safiah; Yaakop, Salmah; Zain, Badrul Munir Md.

2013-11-01

Members of the Opiinae subfamily (Hymenoptera: Braconidae) are well known as important parasitoids of fruit fly larvae (Diptera: Tephritidae). They are widely used as biological control agents of fruit flies, especially the Bactrocera Macquart species that infest fruits. In this study, the larvae of fruit flies were collected from infested crops including star fruit, guava, wax apple and ridge gourd. The parasitized larvae were then reared under laboratory conditions until emergence of the adult parasitoids. Additionally, Malaise trap also was used to collect parasitoid species. The general concept of the multiplex PCR has been performed is to amplify two mitochondrial DNA markers, namely cytochrome oxidase subunit I (COI) and cytochrome b (Cyt b) simultaneously. Therefore, the lengthy process of reaction will be reduced. The status of the fruit fly species has also been confirmed by using COI marker on the early stage of the larvae. Maximum parsimony (MP) and Bayesian Inference (BI) were implemented to help and support the identification of Opiinae species. The result obtained from this study showed three parasitoid genera of the Opiinae viz. Fopius Wharton, Psyttalia Walker and Diachasmimorpha Viereck. Each genus has been determined by clustering together in a similar clade according to their infested crops. Therefore, accurate determination of parasitoids and the fruit fries species was highly useful and necessary for successful biological control of Bactrocera species.

Differences in memory dynamics between two closely related parasitoid wasp species

NARCIS (Netherlands)

Bleeker, M.A.K.; Smid, H.M.; Steidle, J.L.M.; Kruidhof, H.M.; van Loon, J.J.A.; Vet, L.E.M.

2006-01-01

The two closely related parasitoids Cotesia glomerata and C. rubecula (Hymenoptera: Braconidae) coexist in The Netherlands where they occupy slightly different niches. When searching for their caterpillar hosts, they use host plant odours that are released upon feeding by the caterpillars. The

The importance of phenology in studies of plant-herbivore-parasitoid interactions

NARCIS (Netherlands)

Fei, Minghui

2016-01-01

Thesis title: The importance of phenology in studies of plant-herbivore-parasitoid interactions Author: Minghui Fei Abstract As food resources of herbivorous insects, the quality and quantity of plants can directly affect the performance of herbivorous insects and indirectly affect

Metagenomic analysis of microbial community of a parasitoid wasp Megaphragma amalphitanum

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A.V. Nedoluzhko

2017-03-01

Full Text Available The vast majority of multicellular organisms coexist with bacterial symbionts that may play various roles during their life cycle. Parasitoid wasp Megaphragma amalphitanum (Hymenoptera: Trichogrammatidae belongs to the smallest known insects whose size is comparable with some bacteria. Using 16S rRNA gene sequencing and Whole Genome Sequencing (WGS, we described microbiota diversity for this arthropod and its potential impact on their lifecycle. Metagenomic sequences were deposited to SRA database which is available at NCBI with accession number SRX2363723 and SRX2363724. We found that small body size and limited lifespan do not lead to a significant reduction of bacterial symbionts diversity. At the same time, we show here a specific feature of microbiota composition in M. amalphitanum – the absence of the Rickettsiaceae family representatives that are known to cause sex-ratio distortion in arthropods and well represented in other populations of parasitoid wasps.

THE INFLUENCE OF CULTURAL PRACTICE ON POPULATION OF PEA LEAFMINER (Liriomyza huidobrensis AND ITS PARASITOIDS IN POTATO

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Ida Bagus Gde Suryawan

2016-10-01

Full Text Available Pea leafminer (Liriomyza huidobrensis is the major pest of potato crop in Indonesia. The use of insecticides to control the pest is ineffective and harmful to the natural enemies. The study aimed to find out a promising cultural practice for leafminer management on potato crop. The study was conducted at a farmer’s field in Bali in 2004. Potato plants (Granola variety were grown in a raised-bed plot of 10 m x 1 m. The treatments evaluated were standard cultural practice (C, C plus reflective plastic mulch (RPM (CM, farmer’s practice (F, vermicompost (V, and V plus RPM (VM. All treatments were arranged in RCBD with five replications. From each plot, 10 plant samples were randomly taken to observe the presence of larvae, mines, and adults. Larvae and adults of leafminer and mines were separately counted from the top, middle, and bottom parts of the plant samples. Parasitoids were collected from the infested leaves of the plant samples. Emerged parasitoids were counted and put into vials with 70% ethyl alcohol and then identified. The results showed that the population of adults, larvae of L. huidobrensis, and mines were less in C, CM, V, and VM treatments compared to farmer's practice (F. However, RPM (CM and VM treatments significantly reduced population of leafminer and mines. The highest population of adults, larvae, and mines on RPM treatment were less than 1.5, 8.5, and 10 per plant, respectively compared to other treatments which were greater than 3.2 for adults, 12.4 for larvae, and 12.7 for mines. Parasitoid population and parasitism level were more in vermicompost treatments (V and VM compared to other treatments (C, CM, and F. The results showed that application of pesticides was ineffective against leafminer and reduced parasitoid population; in the other hand RPM was effective to control leafminer although the effect on parasitoids was not clear. Parasitoid species that were found associated with potato crop were Hemiptarsenus

Life-history strategies in parasitoid wasps: a comparative analysis of 'ovigeny'

NARCIS (Netherlands)

Jervis, M.A.; Heimpel, G.E.; Ferns, P.N.; Harvey, J.A.; Kidd, N.A.C.

2001-01-01

1. Ecologists concerned with life-history strategies of parasitoid wasps have recently focused on interspecific variation in the fraction of the maximum potential lifetime egg complement that is mature when the female emerges into the environment. Species that have all of this complement mature upon

Semiochemical exploitation of host-associated cues by seven Melittobia parasitoid species

NARCIS (Netherlands)

González, Jorge M.; Camino, Dakota; Simon, Sabrina; Cusumano, Antonino

2018-01-01

Chemical compounds (infochemicals or semiochemicals) play an important role both in intra-specific and inter-specific communication. For example, chemical cues appear to play a key role in the host selection process adopted by insect parasitoids. In recent years significant advances have been made

First extensive characterization of the venom gland from an egg parasitoid

NARCIS (Netherlands)

Cusumano, Antonino; Duvic, Bernard; Jouan, Véronique; Ravallec, Marc; Legeai, Fabrice; Peri, Ezio; Colazza, Stefano; Volkoff, Anne Nathalie

2018-01-01

The venom gland is a ubiquitous organ in Hymenoptera. In insect parasitoids, the venom gland has been shown to have multiple functions including regulation of host immune response, host paralysis, host castration and developmental alteration. However, the role played by the venom gland has been

Botanical insecticides on Liriomyza huidobrensis Blanchard (Diptera: Agromyzidae and its parasitoids in string beans cultivated in a plastic greenhouse

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Sônia Thereza Bastos Dequech

2010-04-01

Full Text Available The string bean (Phaseolus vulgaris L. is one of the most cultivated vegetables in plastic greenhouses in the central region of the state of Rio Grande do Sul. Liriomyza huidobrensis (Dip.: Agromyzidae is one of the most important insect pests occurring in this culture. This research was conducted to evaluate the effect of aqueous extracts of plants and the commercial product DalNeem on L. huidobrensis and its parasitoids, as well as to analyse the population fluctuation of L. huidobrensis and parasitoids of this insect pest. The experiment was carried out on string beans cultivated in a greenhouse, where in each of the four central lines of culture, five plots were established with five plants per plot. The experimental design was random blocks with four replications. DalNeem was the treatment that best controlled L. huidobrensis. On the other hand, the treatments did not affect the parasitoids Chrysocharis bedius (Hym.: Eulophidae or Opius sp. (Hym.: Braconidae. In plants without the use of these treatments, the population of L. huidobrensis exhibited a sharp decline with the increase of the parasitoids C. bedius, Opius sp., Eucoilinae (Hym.: Figitidae and Diptera.

Reciprocal diversification in a complex plant-herbivore-parasitoid food web

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Bokma Folmer

2007-11-01

Full Text Available Abstract Background Plants, plant-feeding insects, and insect parasitoids form some of the most complex and species-rich food webs. According to the classic escape-and-radiate (EAR hypothesis, these hyperdiverse communities result from coevolutionary arms races consisting of successive cycles of enemy escape, radiation, and colonization by new enemy lineages. It has also been suggested that "enemy-free space" provided by novel host plants could promote host shifts by herbivores, and that parasitoids could similarly drive diversification of gall form in insects that induce galls on plants. Because these central coevolutionary hypotheses have never been tested in a phylogenetic framework, we combined phylogenetic information on willow-galling sawflies with data on their host plants, gall types, and enemy communities. Results We found that evolutionary shifts in host plant use and habitat have led to dramatic prunings of parasitoid communities, and that changes in gall phenotype can provide "enemy-free morphospace" for millions of years even in the absence of host plant shifts. Some parasites have nevertheless managed to colonize recently-evolved gall types, and this has apparently led to adaptive speciation in several enemy groups. However, having fewer enemies does not in itself increase speciation probabilities in individual sawfly lineages, partly because the high diversity of the enemy community facilitates compensatory attack by remaining parasite taxa. Conclusion Taken together, our results indicate that niche-dependent parasitism is a major force promoting ecological divergence in herbivorous insects, and that prey divergence can cause speciation in parasite lineages. However, the results also show that the EAR hypothesis is too simplistic for species-rich food webs: instead, diversification seems to be spurred by a continuous stepwise process, in which ecological and phenotypic shifts in prey lineages are followed by a lagged evolutionary

Mountain aphid and parasitoid guilds on Aconitum spp. in Europe

Czech Academy of Sciences Publication Activity Database

Havelka, Jan; Tomanović, Ž.; Kos, K.; Kavallieratos, N. G.; Janeček, J.; Pons, X.; Rakhshani, E.; Starý, Petr

2014-01-01

Roč. 67, č. 1 (2014), s. 57-61 ISSN 1721-8861 Grant - others:Ministry of Education, Science and Technological Development(RS) III43001 Institutional support: RVO:60077344 Keywords : aphis * Aphididae * parasitoids Subject RIV: EH - Ecology, Behaviour Impact factor: 1.494, year: 2014 http://www.bulletinofinsectology.org/pdfarticles/vol67-2014-057-061havelka.pdf

The Behavioural Abilities of Meteorus versicolor Wesm. and Rogas rossicus Kok. (Hymenoptera, Branconidae) Parasitoids of Tephrina arenacearia Den. Et Schiff. (Lepidoptera, Geometridae)

OpenAIRE

KERIMOVA, Ilhama Gudrat Gizi

1998-01-01

This paper concerns with the behavioural abilities of Meteorus versicolor Wesm. and Rogas rossicus Kok. (Hymenoptera, Braconidae)-internal parasitoids of Thephrina arenacearia Den. et Schiff. (Lepidoptera, Geometridae) as well. Periods of development phases and searching, ovipositional and mating behaviour of both parasitoids have been investigated.

Selfish element maintains sex in natural populations of a parasitoid wasp.

NARCIS (Netherlands)

Stouthamer, R.; Tilborg, van M.; Jong, de J.H.; Nunney, L.; Luck, R.F.

2001-01-01

Genomic conflicts between heritable elements with different modes of inheritance are important in the maintenance of sex and in the evolution of sex ratio. Generally, we expect sexual populations to exhibit a 1:1 sex ratio. However, because of their biology, parasitoid wasps often exhibit a

Identification and characterization of bacterial symbionts in three species of filth fly parasitoids.

Science.gov (United States)

Betelman, Kfir; Caspi-Fluger, Ayelet; Shamir, Maayan; Chiel, Elad

2017-09-01

Facultative bacterial symbionts are widespread among insects and have diverse effects on their biology. Here, we focused on bacterial symbionts of three ecologically and economically important filth flies parasitoid species-Spalangia cameroni, Spalangia endius and Muscidifurax raptor. Both Spalangia species harbored a Sodalis bacterium that is closely related to Spalangia praecaptivus (a free-living bacterium) and to Sodalis symbionts of weevils. This is the only case of Sodalis infection in the important order Hymenoptera. We also found, for the first time in this parasitoid guild, a Rickettsia infecting the two Spalangia spp., albeit in much higher prevalence in S. cameroni. Molecular and phylogenetic analyses revealed that it is closely related to Rickettsia felis and other Rickettsia species from the 'transitional' group. All three parasitoid species harbored Wolbachia. Using multi-locus sequence typing, we found that M. raptor harbors a single Wolbachia strain whereas the Spalangia spp. have multiple strains. By controlled crossings, we found that Wolbachia infection in S. endius causes incomplete cytoplasmic incompatibility and increased longevity, thereby promoting Wolbachia's spread. In contrast, no effects of Wolbachia on the reproduction and longevity of M. raptor were found. This study underscores the diversity and nature of symbiotic interactions between microbes and insects. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Seletividade de diferentes agrotóxicos usados na cultura da soja ao parasitoide de ovos Telenomus remus Selectivity of different pesticides used in soybean to the eggs parasitoid Telenomus remus

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Eduardo Lima do Carmo

2009-11-01

Full Text Available A preservação dos agentes de controle biológico no agroecossistema é indispensável para o sucesso do manejo integrado de pragas. Entretanto, o controle químico de pragas ainda é indispensável em diversas culturas. Nesse contexto, a seletividade dos agrotóxicos aos inimigos naturais deve ser sempre considerada na escolha do melhor produto. Portanto, este estudo verificou o impacto causado por diferentes agrotóxicos na emergência do parasitoide de ovos Telenomus remus Nixon (Hymenoptera: Scelionidae, quando aplicados nas fases de larva e pupa (posturas de 100 a 150 ovos de Spodoptera frugiperda (J.E. Smith (Lepidoptera: Noctuidae seis e 10 dias após o parasitismo, respectivamente. Três ensaios, com 11 tratamentos e cinco repetições, foram conduzidos em laboratório com inseticidas, fungicidas e herbicidas, respectivamente. Cada ensaio foi conduzido com 10 tratamentos de agrotóxicos e água como testemunha seletiva. Todos os produtos fitossanitários foram testados nas doses utilizadas na cultura da soja. Ovos de S. frugiperda parasitados por T. remus foram imersos nos tratamentos por cinco segundos e, após secagem total, foram acondicionados em sacos plásticos até a emergência dos adultos dos parasitoides. A viabilidade do parasitismo foi avaliada, e a redução na emergência dos parasitoides foi classificada segundo as normas da International Organization for Biological Control (IOBC. Os resultados mostraram que os inseticidas do grupo dos reguladores de crescimento, como o flufenoxurom, diflubenzurom e metoxifenozido e também os inseticidas imidacloprido + beta-ciflutrina e acefato, foram seletivos às fases imaturas do parasitoide. Espinosade foi classificado como inócuo para larvas de T. remus. Gama-cialotrina foi levemente nocivo para larvas e inócuo para pupas. Bifentrina e clorpirifós foram, respectivamente, levemente nocivo e nocivo para ambas as fases de desenvolvimento de T. remus. Com relação aos herbicidas

Biology, life history, and laboratory rearing of Atanycolus cappaerti (Hymenoptera:Braconidae), a larval parasitoid of the invasive Emerald Ash Borer (Coleoptera: Buprestidae)

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Atanycolus cappaerti Marsh and Strazanac is a native North American parasitoid that has been found to parasitize the invasive emerald ash borer (EAB), Agrilus planipennis Fairmaire, which has killed millions of ash trees since it was first detected in Michigan. A native parasitoid like A. cappaerti...

Dinâmica populacional do parasitoide de ovos erythmelus tingitiphagus (hymenoptera: mymaridae em clone de seringueira, em Itiquira, MT Population dynamic of egg parasitoid erythmelus tingitiphagus (hymenoptera: mymaridae in rubber tree clone in Itiquira, Mato Grosso State, Brazil

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Rodrigo Souza Santos

2013-04-01

Full Text Available O percevejo-de-renda Leptopharsa heveae Drake & Poor (Hemiptera: Tingidae é uma das mais importantes pragas da heveicultura no Brasil, principalmente nas regiões Sudeste e Centro-Oeste. Devido ao seu hábito sugador, na face abaxial das folhas, esta praga leva à senescência precoce das mesmas e a reduções na produção de látex em até 30%. Dentre os inimigos naturais de L. heveae está o parasitoide de ovos Erythmelus tingitiphagus (Soares (Hymenoptera: Mymaridae, regulando suas populações em condições naturais. O objetivo deste estudo foi verificar a dinâmica populacional deste parasitoide, bem como correlacioná-la com os fatores meteorológicos temperatura e pluviosidade, em plantio comercial de seringueira do clone PB 217, em Itiquira, MT. Semanalmente foram coletadas quatro folhas maduras por árvore, no terço inferior da copa de 40 árvores, totalizando 160 folhas por amostragem, no período de agosto de 2006 a janeiro de 2007. Houve correlação positiva entre a dinâmica populacional e os fatores meteorológicos, sendo o pico populacional do parasitoide observado no mês de novembro e declinando até janeiro na área estudada.The lace bug Leptopharsa heveae Drake & Poor (Hemiptera: Tingidae is one of the most import heveiculture pests in Brazil, mainly in the southeast and central-west regions. Due to its sucking habit on the abaxial surface, this pest causes precocious senescence in leaves, and leads to the reduction in latex production in up to 30% of them. Among the natural enemies of L. heveae is the egg parasitoid Erythmelus tingitiphagus (Soares (Hymenoptera: Mymaridae, regulating populations of L. heveae in natural conditions. The objective of this work was to verify the population dynamics of this parasitoid, as well as to correlate it with meteorological factors such as temperature and rainfall, in a commercial plantation of rubber trees of the PB 217 clone, in Itiquira, in the Mato Grosso state, Brazil. Four

Alien dominance of the parasitoid wasp community along an elevation gradient on Hawai'i Island

Science.gov (United States)

Peck, R.W.; Banko, P.C.; Schwarzfeld, M.; Euaparadorn, M.; Brinck, K.W.

2008-01-01

Through intentional and accidental introduction, more than 100 species of alien Ichneumonidae and Braconidae (Hymenoptera) have become established in the Hawaiian Islands. The extent to which these parasitoid wasps have penetrated native wet forests was investigated over a 1,765 m elevation gradient on windward Hawai'i Island. For >1 year, malaise traps were used to continuously monitor parasitoid abundance and species richness in nine sites over three elevations. A total of 18,996 individuals from 16 subfamilies were collected. Overall, the fauna was dominated by aliens, with 44 of 58 species foreign to the Hawaiian Islands. Ichneumonidae was dominant over Braconidae in terms of both diversity and abundance, comprising 67.5% of individuals and 69.0% of species collected. Parasitoid abundance and species richness varied significantly with elevation: abundance was greater at mid and high elevations compared to low elevation while species richness increased with increasing elevation, with all three elevations differing significantly from each other. Nine species purposely introduced to control pest insects were found, but one braconid, Meteorus laphygmae, comprised 98.0% of this assemblage, or 28.3% of the entire fauna. Endemic species, primarily within the genera Spolas and Enicospilus, were collected almost exclusively at mid- and high-elevation sites, where they made up 22.1% and 36.0% of the total catch, respectively. Overall, 75.9% of species and 96.0% of individuals are inferred to parasitize Lepidoptera larvae and pupae. Our results support previous data indicating that alien parasitoids have deeply penetrated native forest habitats and may have substantial impacts on Hawaiian ecosystems. ?? 2008 Springer Science+Business Media B.V.

Associative learning in two closely related parasitoid wasps: a neuroecological approach

NARCIS (Netherlands)

Bleeker, M.A.K.

2005-01-01

Insects are useful model organisms to study learning and memory. Their brains are less complex than vertebrate brains, but the basic mechanisms of learning and memory are similar in both taxa. In this thesis I study learning and subsequent memory formation in two parasitoid wasp species that differ

Evaluation of the host specificity of Spathius galinae (Hymenoptera: Braconidae), a larval parasitoid of the emerald ash borer (Coleoptera: Buprestidae) in Northeast Asia

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Host-specificity determination prior to the introduction of non-native natural enemies (predators and parasitoids) is a critical component of the risk assessment for modern classical biological control programs. In the present study, we assessed the host specificity of a newly described parasitoid,...

Gustatory response and longevity in Aphidius parasitoids and their hyperparasitoid Dendrocerus aphidum

NARCIS (Netherlands)

Goelen, Tim; Baets, Dieter; Kos, Martine; Paulussen, Caroline; Lenaerts, Marijke; Rediers, Hans; Wäckers, F.L.; Jacquemyn, Hans; Lievens, Bart

2018-01-01

Aphid parasitoids are commonly used in the biological control of aphids. However, their success in biological control largely depends on the availability of carbohydrate-rich food as an energy source for maintenance and reproduction. Therefore, as these resources have become rare in modern

Tracking the elusive history of diversification in plant-herbivorous insect-parasitoid food webs: insights from figs and fig wasps.

Science.gov (United States)

Kjellberg, Finn; Proffit, Magali

2016-02-01

The food webs consisting of plants, herbivorous insects and their insect parasitoids are a major component of terrestrial biodiversity. They play a central role in the functioning of all terrestrial ecosystems, and the number of species involved is mind-blowing (Nyman et al. 2015). Nevertheless, our understanding of the evolutionary and ecological determinants of their diversity is still in its infancy. In this issue of Molecular Ecology, Sutton et al. (2016) open a window into the comparative analysis of spatial genetic structuring in a set of comparable multitrophic models, involving highly species-specific interactions: figs and fig wasps. This is the first study to compare genetic structure using population genetics tools in a fig-pollinating wasp (Pleistodontes imperialis sp1) and its main parasitoid (Sycoscapter sp.A). The fig-pollinating wasp has a discontinuous spatial distribution that correlates with genetic differentiation, while the parasitoid bridges the discontinuity by parasitizing other pollinator species on the same host fig tree and presents basically no spatial genetic structure. The full implications of these results for our general understanding of plant-herbivorous insect-insect parasitoids diversification become apparent when envisioned within the framework of recent advances in fig and fig wasp biology. © 2016 John Wiley & Sons Ltd.

Non-pathogenic rhizobacteria interfere with the attraction of parasitoids to aphid-induced plant volatiles via jasmonic acid signalling.

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Pineda, Ana; Soler, Roxina; Weldegergis, Berhane T; Shimwela, Mpoki M; VAN Loon, Joop J A; Dicke, Marcel

2013-02-01

Beneficial soil-borne microbes, such as mycorrhizal fungi or rhizobacteria, can affect the interactions of plants with aboveground insects at several trophic levels. While the mechanisms of interactions with herbivorous insects, that is, the second trophic level, are starting to be understood, it remains unknown how plants mediate the interactions between soil microbes and carnivorous insects, that is, the third trophic level. Using Arabidopsis thaliana Col-0 and the aphid Myzus persicae, we evaluate here the underlying mechanisms involved in the plant-mediated interaction between the non-pathogenic rhizobacterium Pseudomonas fluorescens and the parasitoid Diaeretiella rapae, by combining ecological, chemical and molecular approaches. Rhizobacterial colonization modifies the composition of the blend of herbivore-induced plant volatiles. The volatile blend from rhizobacteria-treated aphid-infested plants is less attractive to an aphid parasitoid, in terms of both olfactory preference behaviour and oviposition, than the volatile blend from aphid-infested plants without rhizobacteria. Importantly, the effect of rhizobacteria on both the emission of herbivore-induced volatiles and parasitoid response to aphid-infested plants is lost in an Arabidopsis mutant (aos/dde2-2) that is impaired in jasmonic acid production. By modifying the blend of herbivore-induced plant volatiles that depend on the jasmonic acid-signalling pathway, root-colonizing microbes interfere with the attraction of parasitoids of leaf herbivores. © 2012 Blackwell Publishing Ltd.

Metabolic and proteomic profiling of diapause in the aphid parasitoid Praon volucre.

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Hervé Colinet

Full Text Available BACKGROUND: Diapause, a condition of developmental arrest and metabolic depression exhibited by a wide range of animals is accompanied by complex physiological and biochemical changes that generally enhance environmental stress tolerance and synchronize reproduction. Even though some aspects of diapause have been well characterized, very little is known about the full range of molecular and biochemical modifications underlying diapause in non-model organisms. METHODOLOGY/PRINCIPAL FINDINGS: In this study we focused on the parasitic wasp, Praon volucre that exhibits a pupal diapause in response to environmental signals. System-wide metabolic changes occurring during diapause were investigated using GC-MS metabolic fingerprinting. Moreover, proteomic changes were studied in diapausing versus non-diapausing phenotypes using a combination of two-dimensional differential gel electrophoresis (2D-DIGE and mass spectrometry. We found a reduction of Krebs cycle intermediates which most likely resulted from the metabolic depression. Glycolysis was galvanized, probably to favor polyols biosynthesis. Diapausing parasitoids accumulated high levels of cryoprotective polyols, especially sorbitol. A large set of proteins were modulated during diapause and these were involved in various functions such as remodeling of cytoskeleton and cuticle, stress tolerance, protein turnover, lipid metabolism and various metabolic enzymes. CONCLUSIONS/SIGNIFICANCE: The results presented here provide some first clues about the molecular and biochemical events that characterize the diapause syndrome in aphid parasitoids. These data are useful for probing potential commonality of parasitoids diapause with other taxa and they will help creating a general understanding of diapause underpinnings and a background for future interpretations.

Study on the Hymenoptera parasitoid associated with Lepidoptera larvae in reforestation and agrosilvopastoral systems at Fazenda Canchim (Embrapa Pecuária Sudeste) São Carlos, SP, Brazil.

Science.gov (United States)

Pereira, A G; Silva, R B; Dias, M M; Penteado-Dias, A M

2015-11-01

The aim of this study was to characterize the local fauna of Hymenoptera parasitoids associated with Lepidoptera larvae in areas of reforestation and agrosilvopastoral systems at Fazenda Canchim (Embrapa Pecuária Sudeste, São Carlos, SP, Brazil). Lepidoptera larvae collected with entomological umbrella were kept in the laboratory until emergence of adults or their parasitoids. From those collected in the agrosilvopastoral system, emerged 267 specimens of hymenopteran parasitoids belonging to 16 genera: Braconidae, Agathidinae (Alabagrus), Braconinae (Bracon), Microgastrinae (Cotesia, Diolcogaster, Glyptapanteles, Pholetesor and Protapanteles), Orgilinae (Orgilus); Ichneumonidae, Campopleginae (Casinaria, Charops and Microcharops); Chalcididae, Chalcidinae (Brachymeria and Conura); Eulophidae, Entedoninae (Horismenus), Eulophinae (Elachertus and Euplectrus). From the Lepidoptera larvae collected in the reforestation, emerged 68 specimens of hymenopteran parasitoids, belonging to 8 genera: Chalcididae, Chalcidinae (Conura); Ichneumonidae, Pimplinae (Neotheronia), Campopleginae (Charops and Microcharops) and Braconidae, Microgastrinae (Apanteles, Diolcogaster, Distatrix, Glyptapanteles and Protapanteles). The results of this study suggest the occurrence of a wide variety of Hymenoptera parasitoids in the studied environments.

Study on the Hymenoptera parasitoid associated with Lepidoptera larvae in reforestation and agrosilvopastoral systems at Fazenda Canchim (Embrapa Pecuária Sudeste São Carlos, SP, Brazil

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A. G. Pereira

Full Text Available Abstract The aim of this study was to characterize the local fauna of Hymenoptera parasitoids associated with Lepidoptera larvae in areas of reforestation and agrosilvopastoral systems at Fazenda Canchim (Embrapa Pecuária Sudeste, São Carlos, SP, Brazil. Lepidoptera larvae collected with entomological umbrella were kept in the laboratory until emergence of adults or their parasitoids. From those collected in the agrosilvopastoral system, emerged 267 specimens of hymenopteran parasitoids belonging to 16 genera: Braconidae, Agathidinae (Alabagrus, Braconinae (Bracon, Microgastrinae (Cotesia, Diolcogaster, Glyptapanteles, Pholetesor and Protapanteles, Orgilinae (Orgilus; Ichneumonidae, Campopleginae (Casinaria, Charops and Microcharops; Chalcididae, Chalcidinae (Brachymeria and Conura; Eulophidae, Entedoninae (Horismenus, Eulophinae (Elachertus and Euplectrus. From the Lepidoptera larvae collected in the reforestation, emerged 68 specimens of hymenopteran parasitoids, belonging to 8 genera: Chalcididae, Chalcidinae (Conura; Ichneumonidae, Pimplinae (Neotheronia, Campopleginae (Charops and Microcharops and Braconidae, Microgastrinae (Apanteles, Diolcogaster, Distatrix, Glyptapanteles and Protapanteles. The results of this study suggest the occurrence of a wide variety of Hymenoptera parasitoids in the studied environments.

Susceptibility of the Parasitoid Phymastichus coffea LaSalle (Hymenoptera: Eulophidae) to Beauveria bassiana under laboratory conditions; Susceptibilidad del parasitoide Phymastichus coffea LaSalle (Hymenoptera:Eulophidae) a Beauveria bassiana en condiciones de laboratorio

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Castillo, Alfredo; Gomez, Jaime; Infante, Francisco [El Colegio de la Frontera Sur (ECOSUR), Chiapas (Mexico). Dept. de Entomologia Tropical], e-mail: acastill@ecosur.mx, e-mail: jgomez@ecosur.mx, e-mail: finfante@ecosur.mx; Vega, Fernando E. [United States Department of Agriculture (USDA), Beltsville, MD (United States). Agricultural Research Service. Sustainable Perennial Crops Lab.], e-mail: fernando.vega@ars.usda.gov

2009-09-15

The coffee berry borer, Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae), is the most important coffee pest worldwide. Beauveria bassiana is a generalist entomopathogenic fungus widely used by coffee farmers to control this pest and Phymastichus coffea LaSalle (Hymenoptera: Eulophidae) is an African endo parasitoid of H. hampei adults, recently imported to several Latin American and Caribbean countries to aid in the coffee berry borer control. The objective of this study was to determine if B. bassiana is detrimental to P. coffea. The susceptibility of the parasitoid was evaluated in terms of adult survivorship, mean lethal concentration (LC{sub 50}), mean lethal time (LT{sub 50}), reproduction and immature mortality. The main effect of the fungus resulted in reduction of adult longevity and mortality of 100% for immature stages of this parasitoid. The LC{sub 50} for adults was 0.11% equivalent to 9.53 x 10{sup 7} conidia/ml of B. bassiana and a LT{sub 50} of 29.4 h, equivalent to reduction of 22% of its normal longevity as an adult. P. coffea was capable of disseminating spores of B. bassiana to non-infected H. hampei adults, which could indirectly cause the death of its own progeny. These results could be valuable when considering the use of both organisms in the field, especially in an integrated pest management program. (author)

Study on the Hymenoptera parasitoid associated with Lepidoptera larvae in reforestation and agrosilvopastoral systems at Fazenda Canchim (Embrapa Pecuária Sudeste) São Carlos, SP, Brazil

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Pereira,A. G.; Silva,R. B.; Dias,M. M.; Penteado-Dias,A. M.

2015-01-01

Abstract The aim of this study was to characterize the local fauna of Hymenoptera parasitoids associated with Lepidoptera larvae in areas of reforestation and agrosilvopastoral systems at Fazenda Canchim (Embrapa Pecuária Sudeste, São Carlos, SP, Brazil). Lepidoptera larvae collected with entomological umbrella were kept in the laboratory until emergence of adults or their parasitoids. From those collected in the agrosilvopastoral system, emerged 267 specimens of hymenopteran parasitoids belo...

The dipteran parasitoid Exorista bombycis induces pro- and anti-oxidative reactions in the silkworm Bombyx mori: Enzymatic and genetic analysis.

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Makwana, Pooja; Pradeep, Appukuttan Nair R; Hungund, Shambhavi P; Ponnuvel, Kangayam M; Trivedy, Kanika

2017-02-01

Hymenopteran parasitoids inject various factors including polydnaviruses along with their eggs into their host insects that suppress host immunity reactions to the eggs and larvae. Less is known about the mechanisms evolved in dipteran parasitoids that suppress host immunity. Here we report that the dipteran, Exorista bombycis, parasitization leads to pro-oxidative reactions and activation of anti-oxidative enzymes in the silkworm Bombyx mori larva. We recorded increased activity of oxidase, superoxide dismutase, thioredoxin peroxidase, catalase, glutathione-S-transferase (GST), and peroxidases in the hemolymph plasma, hemocytes, and fat body collected from B. mori after E. bombycis parasitization. Microarray and qPCR showed differential expression of genes encoding pro- and anti-oxidant enzymes in the hemocytes. The significance of this work lies in increased understanding of dipteran parasitoid biology. © 2017 Wiley Periodicals, Inc.

The impact of resource limitation and the phenology of parasitoid attack on the duration of insect herbivore outbreaks.

Science.gov (United States)

Umbanhowar, James; Hastings, Alan

2002-11-01

Fluctuations in resource quality and quantity, and changes in mortality due to predators and parasites are thought to be of prime importance in the regular fluctuations of forest insects. We examine how food limitation and parasitoids with different phenologies of attack regulate the population cycles of insect hosts. Our analysis of the limit cycle of a model with a biologically realistic form of density dependence in the host yields two novel predictions. First, outbreaks will typically last for only 2 generations after parasitoids begin to reduce the host population below the maximum density. Second, host growth rate is important in determining cycle length only when parasitoids attack before the impacts of resource limitation affect the host. The robustness of these predictions are tested using a more general form of density dependence in the host, revealing that our predictions are valid as long as density dependence in the host is not too overcompensatory.

Surveys for Stenoma catenifer (Lepidoptera: Elachistidae) and associated parasitoids infesting avocados in Perú.

Science.gov (United States)

Hoddle, Mark S; Hoddle, Christina D

2012-04-01

Surveys for Stenoma catenifer Walsingham, the avocado seed moth, and its associated larval parasitoids were conducted in the Departments of Junín, Huánuco, Cusco, and Madre de Dios in Perú. Fruit infestation levels in some areas ranged from 0 to 58%, and parasitism of S. catenifer larvae in Junín and Huánuco was 23%. Five species of hymenopteran parasitoid in two families, Braconidae (Apanteles sp., Hypomicrogaster sp., and Chelonus sp.) and Ichneumonidae (Pristeromerus sp. and Xiphosomella sp.), were reared from larvae, and one species of tachinid fly (Chrysodoria sp.) emerged from pupae. The dominant larval parasitoid, a gregarious Apanteles sp., accounted for 55% of parasitized hosts. Branch and twig tunneling by S. catenifer larvae in a commercial Hass avocado orchard was observed in Cusco. The field attractiveness of the sex pheromone of S. catenifer was demonstrated with 73% of monitoring traps deployed in three departments (Junín, Huánuco, and Cusco) catching male moths. Approximately 55% of avocado fruit sourced from the Province of Chanchamayo (Junin) and purchased at the Mercado Modelo de Frutas in La Victoria, in central Lima were infested with larvae of S. catenifer. Infested avocado fruit sold at this market could represent a potential incursion threat to coastal Hass avocado production regions in Perú that are reportedly free of this pest.

Biological Control of Solenopsis Fire Ants by Pseudacteon Parasitoids: Theory and Practice

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Lloyd W. Morrison

2012-01-01

Full Text Available Pseudacteon parasitoids are potential biocontrol agents of invasive Solenopsis fire ants. Pseudacteon species that parasitize the invasive S. invicta Buren and S. richteri Forel have been introduced to, and naturally dispersed across, the southeastern USA, although there is no evidence yet that Solenopsis host ant populations have decreased. The ability of introduced Pseudacteon species to regulate Solenopsis populations will depend upon the relative importance of top-down effects in the recipient communities. In this paper, I examine the characteristics of the Pseudacteon/Solenopsis parasitoid/host system and evaluate the extent to which research findings are consistent with top-down control. Laboratory and field experiments evaluating Solenopsis population regulation have been equivocal, and overall the available evidence provides little support for strong top-down effects in this system. Competitive exclusion may occur among introduced Pseudacteon species, and future efforts at biological control are likely to be more efficacious if they focus on other types of natural enemies.

Spatio-Temporal Dynamics of Viruses are Differentially Affected by Parasitoids Depending on the Mode of Transmission

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Elisa Viñuela

2012-11-01

Full Text Available Relationships between agents in multitrophic systems are complex and very specific. Insect-transmitted plant viruses are completely dependent on the behaviour and distribution patterns of their vectors. The presence of natural enemies may directly affect aphid behaviour and spread of plant viruses, as the escape response of aphids might cause a potential risk for virus dispersal. The spatio-temporal dynamics of Cucumber mosaic virus (CMV and Cucurbit aphid-borne yellows virus (CABYV, transmitted by Aphis gossypii in a non-persistent and persistent manner, respectively, were evaluated at short and long term in the presence and absence of the aphid parasitoid, Aphidius colemani. SADIE methodology was used to study the distribution patterns of both the virus and its vector, and their degree of association. Results suggested that parasitoids promoted aphid dispersion at short term, which enhanced CMV spread, though consequences of parasitism suggest potential benefits for disease control at long term. Furthermore, A. colemani significantly limited the spread and incidence of the persistent virus CABYV at long term. The impact of aphid parasitoids on the dispersal of plant viruses with different transmission modes is discussed.

Impact of insecticides on parasitoids of the leafminer, Liriomyza trifolii, in pepper in south Texas.

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Hernández, Ricardo; Harris, Marvin; Liu, Tong-Xian

2011-01-01

Liriomyza leafminers (Diptera: Agromyzidae) are cosmopolitan, polyphagous pests of horticultural plants and many are resistant to insecticides. Producers in South Texas rely on insecticides as the primary management tool for leafminers, and several compounds are available. The objective of this study is to address the efficacy of these compounds for controlling Liriomyza while minimizing their effects against natural enemies. Research plots were established at Texas AgriLife research center at Weslaco, Texas in fall 2007 and spring 2008 seasons, and peppers were used as a model crop. Plots were sprayed with novaluron, abamectin, spinetoram, lambda-cyhalothrin and water as treatments according to leafminer infestation; insecticide efficacy was monitored by collecting leaves and infested foliage. Plant phenology was also monitored. Novaluron was the most effective insecticide and lambda-cyhalothrin showed resurgence in leafminer density in fall 2007 and no reduction in spring 2008. Other compounds varied in efficacy. Novaluron showed the least number of parasitoids per leafminer larva and the lowest parasitoid diversity index among treatments followed by spinetoram. Liriomyza trifolii (Burgess) was the sole leafminer species on peppers, and 19 parasitoid species were found associated with this leafminer. Application of these insecticides for management of leafminers with conservation of natural enemies is discussed.

A checklist of the species of Anastrepha with the families of their host plants and hymenopteran parasitoids in Brazil

International Nuclear Information System (INIS)

Zucchi, Roberto Antonio

2000-01-01

Many surveys on fruit flies have already been carried out by several researchers in Brazil while others are still going on. Most of these surveys were conducted in areas where no studies had been previously done. With these surveys, new species and new records of species were found in Brazil. Also, in this decade, several surveys on fruit fly braconid parasitoids were conducted. These data have been summarised recently, because of the great interest in the biological control of fruit flies in Brazil. Research on eucoilid fruit fly parasitoids have been largely neglected. However, taxonomic studies are being conducted on eucoilids associated with frugivorous flies (Tephritidae and Lonchaeidae) in Brazil. All the data on fruit flies, host plants and hymenopteran parasitoids are unfortunately scattered in the literature and frequently are only published as dissertations or congress abstracts which are not widely available. Even when submitted for publication, papers take a long time to come out in Brazil. Consequently, it is very difficult to get a list of the Anastrepha species in Brazil, or to determine which host plant species are associated with them. These data are of particular interest in the case of economically important species, especially those considered as quarantine pests. Therefore, such a list is very useful for regulatory entomologists and pest management programmes by listing the Anastrepha species in Brazil and their associated host plants and hymenopteran parasitoids. The objective of this paper is to gather some available records of the Anastrepha species, their host plants and hymenopteran parasitoids (Braconidae and Eucoilidae) published in Brazil. Due to the space limitation of this paper, only families of the host plants of the Anastrepha species are presented. In fact, this work is part of a research which deals with the preparation of a database for the Anastrepha species in Brazil

The Gastropod Menace: Slugs on Brassica Plants Affect Caterpillar Survival through Consumption and Interference with Parasitoid Attraction.

Science.gov (United States)

Desurmont, Gaylord A; Zemanova, Miriam A; Turlings, Ted C J

2016-03-01

Terrestrial molluscs and insect herbivores play a major role as plant consumers in a number of ecosystems, but their direct and indirect interactions have hardly been explored. The omnivorous nature of slugs makes them potential disrupters of predator-prey relationships, as a direct threat to small insects and through indirect, plant-mediated effects. Here, we examined the effects of the presence of two species of slugs, Arion rufus (native) and A. vulgaris (invasive) on the survivorship of young Pieris brassicae caterpillars when feeding on Brassica rapa plants, and on plant attractiveness to the main natural enemy of P. brassicae, the parasitoid Cotesia glomerata. In two separate predation experiments, caterpillar mortality was significantly higher on plants co-infested with A. rufus or A. vulgaris. Moreover, caterpillar mortality correlated positively with slug mass and leaf consumption by A. vulgaris. At the third trophic level, plants infested with slugs and plants co-infested with slugs and caterpillars were far less attractive to parasitoids than plants damaged by caterpillars only, independently of slug species. Chemical analyses confirmed that volatile emissions, which provide foraging cues for parasitoids, were strongly reduced in co-infested plants. Our study shows that the presence of slugs has the potential to affect insect populations, directly via consumptive effects, and indirectly via changes in plant volatiles that result in a reduced attraction of natural enemies. The fitness cost for P. brassicae imposed by increased mortality in presence of slugs may be counterbalanced by the benefit of escaping its parasitoids.

Parasitoid complex of the mealybug Oracella acuta (Lobdell) (Hemiptera: Pseudococcidae), in Georgia, USA

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Jiang-Hua Sun; Stephen R. Clarke; Gary L. Debarr; C. Wayne Berisford

2004-01-01

The parasitoid complex of the mealybug Oracella acuta (Lobdell) was examined in two field populations in Georgia in 1995-96. Allotropa n. sp. and Zarhopalus debarri Sun were the primary endoparasitoids emerging from 0. acuta. Adult abundance varied seasonally, with Allotropa...

The Endosymbiont Arsenophonus Is Widespread in Soybean Aphid, Aphis glycines, but Does Not Provide Protection from Parasitoids or a Fungal Pathogen

Science.gov (United States)

Wulff, Jason A.; Buckman, Karrie A.; Wu, Kongming; Heimpel, George E.; White, Jennifer A.

2013-01-01

Aphids commonly harbor bacterial facultative symbionts that have a variety of effects upon their aphid hosts, including defense against hymenopteran parasitoids and fungal pathogens. The soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), is infected with the symbiont Arsenophonus sp., which has an unknown role in its aphid host. Our research goals were to document the infection frequency and diversity of the symbiont in field-collected soybean aphids, and to determine whether Arsenophonus is defending soybean aphid against natural enemies. We performed diagnostic PCR and sequenced four Arsenophonus genes in soybean aphids from their native and introduced range to estimate infection frequency and genetic diversity, and found that Arsenophonus infection is highly prevalent and genetically uniform. To evaluate the defensive role of Arsenophonus, we cured two aphid genotypes of their natural Arsenophonus infection through ampicillin microinjection, resulting in infected and uninfected isolines within the same genetic background. These isolines were subjected to parasitoid assays using a recently introduced biological control agent, Binodoxys communis [Braconidae], a naturally recruited parasitoid, Aphelinus certus [Aphelinidae], and a commercially available biological control agent, Aphidius colemani [Braconidae]. We also assayed the effect of the common aphid fungal pathogen, Pandora neoaphidis (Remaudiere & Hennebert) Humber (Entomophthorales: Entomophthoraceae), on the same aphid isolines. We did not find differences in successful parasitism for any of the parasitoid species, nor did we find differences in P. neoaphidis infection between our treatments. Our conclusion is that Arsenophonus does not defend its soybean aphid host against these major parasitoid and fungal natural enemies. PMID:23614027

Acute Toxicity of Fresh and Aged Residues of Pesticides to the Parasitoid Tamarixia radiata and to the HLB-Bacteria Vector Diaphorina citri.

Science.gov (United States)

Beloti, V H; Alves, G R; Moral, R A; Demétrio, C G B; Yamamoto, P T

2018-06-01

One method for controlling the Asian citrus psyllid (ACP) Diaphorina citri Kuwayama, the vector of the putative causal agent of Huanglongbing, uses the parasitoid Tamarixia radiata (Waterston). However, the general intensive use of insecticides has reduced the numbers of this parasitoid. This study evaluated the effect of the residual action of 24 insecticides on T. radiata and also determined the differential toxicity of insecticides to D. citri and T. radiata, using three bioassays. In the first, when adults of the parasitoid were exposed to residues of the 24 insecticides, ten were considered short-life (class 1), six slightly persistent (class 2), five moderately persistent (class 3), and three insecticides were considered persistent (class 4), under the IOBC/WPRS classification system. The second bioassay evaluated the sublethal concentrations of the persistent insecticides (formetanate, dimethoate, spinosad). Increasing the concentrations of the insecticides increased the number that were classified as persistent. In the third bioassay, evaluation of the differential toxicity of eight insecticides to the ACP and the parasitoid showed that chlorpyrifos and bifenthrin were more harmful to T. radiata. Therefore, these two insecticides are not recommended for application at the time of parasitoid release. Cypermethrin, imidacloprid, and dimethoate caused higher mortality of D. citri and are most often recommended in IPM programs. The choice of an insecticide for the control of citrus pests must be made with care, aiming to preserve the natural enemies in the ecosystem, and thereby contribute to the success of biological control.

KAPASITAS REPRODUKSI PARASITOID TELUR Trichogrammatoidea nana Zehntner (Hymenoptera:Trichogrammatidae

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- Sujak

2011-09-01

Full Text Available Trichogramma nana is one species of egg parasitoids that are polifag. insect pests that attack crops such as soybean pod borer and rice. Research conducted at the Laboratory of Entomology Research Institute for Tobacco and Fiber Crops Malang in March until June 2009 that aims to determine the reproductive capacity of T. nana on eggs  C. cephalonica. Reproductive capacity of T. nana allegedly using the net reproductive rate (Ro, estimatedtime of one generation (T, the capacity of population growth (r, and the rate of parasitoids per day (λ. T. nana were tested  came from the rice stem borer  eggs collected from the land in the district of East Java Beji Pasuruan. Eggs C.cephalonica which is used as the host is the result of breeding in the laboratory of Entomology Research Institute for Tobacco and Fiber Crops. The results showed that T. nana has greatpotential  as  biological agents.  Most  female  progeny  produced by adult females aged 1-2 days . On the first day produced 12 and 8 tails on the second day or 40% and 27% of the total of 30 females produced by a female during life.  Reproductive capacity of  T. nana on eggs C. cephalonica the net reproductive rate  Ro = 44.7, Capacity of population growth (r = 1.78,  parasitoid growth rate per day (λ=5.9, and mean - mean length of generation (T = 10, 9 days.

Dirhinus giffardii (Hymenoptera: Chalcididae, parasitoid affecting Black Soldier Fly production systems in West Africa

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Emilie Devic

2015-12-01

Full Text Available Interest for insect farming is currently growing globally. Conditions in West Africa appear suitable for developing such farming systems that can benefit communities by improving livelihoods, food and feed security or sanitation. In Ghana and Mali, the Black Soldier Fly (Hermetia illucens Linnaeus, 1758 is being produced for waste recycling and animal feed. In a two stages process (egg and larvae production, egg production was hampered by a pupal parasitoid, Dirhinus giffardii Silvestri, 1913 (Hymenoptera: Chalcididae, which reduced future broodstock by almost 72%. This is the first time D. giffardii is reported as a parasitoid of H. illucens pupae and one of the first reports of parasitism in this commercially important fly species. The introduction of precautionary measures is highly recommended for the success of H. illucens production systems in West Africa.

Habitat amount modulates the effect of patch isolation on host-parasitoid interactions

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Valérie eCoudrain

2014-06-01

Full Text Available 1.Habitat amount and patch isolation are important determinants of biodiversity and ecosystem functioning. We studied the separate and interactive effects of these two components of habitat fragmentation on host-parasitoid interactions in a replicated landscape-scale study. 2.We used trap-nesting solitary bees, wasps and their natural enemies as study system. We exposed trap nests in 30 tree patches in agricultural landscapes in northern Switzerland. Study sites were either (i adjacent to forest (adjacent, (ii distant from forest but connected through woody elements (connected or (iii distant from forest with no connecting woody elements (isolated. Independent of the three levels of isolation, the amount of woody habitat in the landscapes covered a gradient from 4 to 74%. 3.Host and parasitoid species richness increased with the amount of habitat in the landscape and was strongly reduced at isolated compared to adjacent and connected sites. Loss of host species richness was 21% at isolated compared to non-isolated sites, whereas parasitoid species richness decreased by 68%, indicating that the higher trophic level was more adversely affected by isolation. Most importantly, habitat amount and isolation had a pronounced interactive effect on parasitism: while isolation resulted in a strong decrease in parasitism in landscapes with low habitat amount, this effect was mitigated by high habitat amount. These interactive effects were consistent across the three years of the study. 4.The observed interplay between habitat amount and patch isolation may explain the often conflicting results in the habitat fragmentation literature and should be considered in future research on multitrophic communities and ecosystem functioning in fragmented landscapes.

Occurrence of the rare root aphid parasitoid, Aclitus obscuripennis (Hymenoptera: Braconidae: Aphidiinae) in Iran

Czech Academy of Sciences Publication Activity Database

Farahani, S.; Talebi, A. A.; Starý, Petr; Rakhshani, E.

2017-01-01

Roč. 72, č. 12 (2017), s. 1494-1498 ISSN 0006-3088 Institutional support: RVO:60077344 Keywords : Western Asia * new record * parasitoid wasps Subject RIV: EG - Zoology OBOR OECD: Zoology Impact factor: 0.759, year: 2016

Multistep bioassay to predict recolonization potential of emerging parasitoids after a pesticide treatment.

Science.gov (United States)

Desneux, Nicolas; Ramirez-Romero, Ricardo; Kaiser, Laure

2006-10-01

Neurotoxic pyrethroid insecticides are widely used for crop protection, and lethal and sublethal perturbations can be expected in beneficial insects. Under laboratory conditions, the lethal and sublethal effects of deltamethrin on the aphid parasitoid Diaeretiella rapae M'Intosh (Hymenoptera: Braconidae) were studied at the mummy stage and in emerging adults. Following a multistep bioassay, analyses were aimed at evaluating the effects of deltamethrin at various crucial steps in the recolonization process following a deltamethrin treatment: Parasitoid pupal development (emergence from the mummies), adult survival, and host-searching capacity. A four-armed olfactometer was used to investigate the effect of deltamethrin on host-searching behavior (a range of concentrations causing 0.4-79.4% mortality was tested), and a Potter tower was used to test the deltamethrin effect with a realistic application method (four concentrations were tested: 0.5, 5.0, 6.25, and 50 g active ingredient [a.i.]/ha). Deltamethrin reduced the percentage of emergence from mummies, but only when exposed to the 50 g a.i./ha concentration. However, for all concentrations tested, the insecticide induced a decrease in longevity after emergence from sprayed mummies and significant adult mortality when parasitoids walked on fresh residues on leaves. Indices were defined and predicted a high mortality and, thus, reduction of recolonization capacities. However, deltamethrin had no effect on orientation behavior toward aphid-infested plants for adults that survived a residual exposure to the insecticide. The impact of deltamethrin on recolonization via pupal emergence and interest in the methodology used are discussed.

Monitoring the establishment and flight phenology of egg and larval parasitoids of emerald ash borer (Coleoptera: Buprestidae) in Michigan, USA using sentinel eggs and larvae

Science.gov (United States)

Emerald ash borer (EAB), Agrilus planipennis Fairmaire, is an important invasive pest of ash (Fraxinus) trees in North America. Two larval parasitoids, Tetrastichus planipennisi Yang and Spathius agrili Yang, and one egg parasitoid, Oobius agrili Zhang and Huang, were introduced into the United Sta...

Plant surface wax affects parasitoid's response to host footprints

Science.gov (United States)

Rostás, Michael; Ruf, Daniel; Zabka, Vanessa; Hildebrandt, Ulrich

2008-10-01

The plant surface is the substrate upon which herbivorous insects and natural enemies meet and thus represents the stage for interactions between the three trophic levels. Plant surfaces are covered by an epicuticular wax layer which is highly variable depending on species, cultivar or plant part. Differences in wax chemistry may modulate ecological interactions. We explored whether caterpillars of Spodoptera frugiperda, when walking over a plant surface, leave a chemical trail (kairomones) that can be detected by the parasitoid Cotesia marginiventris. Chemistry and micromorphology of cuticular waxes of two barley eceriferum wax mutants ( cer-za.126, cer-yp.949) and wild-type cv. Bonus (wt) were assessed. The plants were then used to investigate potential surface effects on the detectability of caterpillar kairomones. Here we provide evidence that C. marginiventris responds to chemical footprints of its host. Parasitoids were able to detect the kairomone on wild-type plants and on both cer mutants but the response to cer-yp.949 (reduced wax, high aldehyde fraction) was less pronounced. Experiments with caterpillar-treated wt and mutant leaves offered simultaneously, confirmed this observation: no difference in wasp response was found when wt was tested against cer-za.126 (reduced wax, wt-like chemical composition) but wt was significantly more attractive than cer-yp.949. This demonstrates for the first time that the wax layer can modulate the detectability of host kairomones.

Parasitoids attacking emerald ash borers in western Pennsylvania and their potential use in biological control

Science.gov (United States)

J.J. Duan; R.W. Fuester; J. Wildonger; P.B. Taylor; S. Barth; S-E. Spichiger

2009-01-01

Current biological control programs against the emerald ash borer (EAB, Agrilus planipennis Fairmaire) have primarily focused on the introduction and releases of exotic parasitoids from China, home of the pest origin....

Evaluation of recovery and monitoring methods for parasitoids released against Emerald Ash Borer

Science.gov (United States)

The emerald ash borer (Agrilus planipennis Fairmaire, EAB) is an invasive insect pest, and the target of an extensive biological control campaign designed to mitigate EAB driven ash tree (Fraxinus spp.) mortality. Since 2007, environmental releases of three species of hymenopteran parasitoids of EA...

Checklist of Aphidiine parasitoids (Hymenoptera: Braconidae) and their host aphid associations in Iran

Czech Academy of Sciences Publication Activity Database

Barahoei, H.; Rakhshani, E.; Nader, E.; Starý, Petr; Kavallieratos, N. G.; Tomanović, Ž.; Mehrparvar, M.

2014-01-01

Roč. 3, č. 2 (2014), s. 199-232 ISSN 2251-9041 Grant - others:University of Zabol(IR) 89-9198; Ministry of Education, Science and Technological Development of the Republic of Serbia(IR) III43001 Institutional support: RVO:60077344 Keywords : fauna * aphid parasitoids * host association

Parasitoid complex of Stereonychus fraxini (De Geer) (Coleoptera, Curculionidae) in Serbia

Czech Academy of Sciences Publication Activity Database

Drekić, M.; Mihajlović, L. J.; Lozan, Aurel

2013-01-01

Roč. 65, č. 2 (2013), s. 733-737 ISSN 0354-4664 Grant - others:Ministry of Education and Science of the Republic of Serbia(RS) III 43002 Institutional support: RVO:60077344 Keywords : Stereonychus fraxini * parasitoids * Serbia Subject RIV: EH - Ecology, Behaviour Impact factor: 0.607, year: 2013 http://www.doiserbia.nb.rs/img/doi/0354-4664/2013/0354-46641302733D.pdf

The effects of aphid traits on parasitoids host use and specialist advantage

Czech Academy of Sciences Publication Activity Database

Gagic, V.; Petrović-Obradović, O.; Fründ, J.; Kavallieratos, N. G.; Athanassiou, C. G.; Starý, Petr; Tomanović, Ž.

2016-01-01

Roč. 11, č. 6 (2016), č. článku e0157674. E-ISSN 1932-6203 Institutional support: RVO:60077344 Keywords : aphid * parasitoid species * European countries Subject RIV: EH - Ecology, Behaviour Impact factor: 2.806, year: 2016 http://journals.plos.org/plosone/article/asset?id=10.1371%2Fjournal.pone.0157674.PDF

Assessing the suitability of flowering herbs as parasitoid food sources: flower attractiveness and nectar accessibility

NARCIS (Netherlands)

Wäckers, F.L.

2004-01-01

Eleven insect-pollinated plant species were investigated with respect to their olfactory attractiveness and nectar accessibility for the parasitoid species Cotesia glomerata (Hymenoptera: Braconidae), Heterospilus prosopidis (Hymenoptera: Braconidae), and Pimpla turionellae (Hymenoptera:

Assessing non-target effects and host feeding of the exotic parasitoid Apanteles taragamae, a potential biological control agent of the cowpea pod borer Maruca vitrata

NARCIS (Netherlands)

Dannon, A.E.; Tamo, M.; Huis, van A.; Dicke, M.

2012-01-01

Apanteles taragamae Viereck is a larval parasitoid introduced in Benin for classical biological control of the cowpea pod borer Maruca vitrata Fabricius. In the laboratory, we evaluated the effects of A. taragamae on non-target herbivore species, and on another parasitoid of M. vitrata, i.e. the

Analisis senyawa volatil dari ekstrak tanaman yang berpotensi sebagai atraktan parasitoid telur wereng batang coklat, Anagrus nilaparvatae (Pang et Wang (Hymenoptera: Mymaridae

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Surjani Wonorahardjo

2015-09-01

Full Text Available Plants produce volatiles as communication cues intra- or inter- species. Infested plants by herbivores will produce volatiles as indirect defense mechanism that attracts natural enemies of herbivores. Analysis of volatiles compounds produced by rice plant as result of infested brown plant hopper (BPH, Nilaparvata lugens Stâl, was done to identify compounds in the volatiles that potentially can be used as attractant for egg parasitoids of BPH, Anagrus nilaparvatae (Pang et Wang (Hymenoptera: Mymaridae. This research was an early stage to develop formulation of parasitoid attractant. The research activities include volatiles extraction of infested rice stem by BPH eggs using acetone, n-hexane as the extraction solvents; analyses of volatile compounds with GC-MS; and bioassay of parasitoid orientation behavior to the volatiles using olfactometer methods. Extraction methods applied were maceration and continuous extraction followed by concentration. Bioassay on the parasitoid orientation behavior was done by using Y-tube olfactometer and every lot of bioassay using 30 parasitoid females with 3 replicates. The results showed that the volatile compounds of extract of infested rice stem by BPH eggs comprise of 16 components. The highest proportion of the components extracted with acetone is 2-Pentanone, 4-hydroxy-4-methyl (19,9%, while those with n-hexane is Hexanedioic acid, dioctyl ester (65%. A. nilaparvatae showed positive response to the volatiles extracted from infested rice plant by N. lugens eggs. Therefore, the volatiles can be used as an attractant for the egg A. nilaparvatae to support rice pest management.

Parallel and costly changes to cellular immunity underlie the evolution of parasitoid resistance in three Drosophila species.

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John E McGonigle

2017-10-01

Full Text Available A priority for biomedical research is to understand the causes of variation in susceptibility to infection. To investigate genetic variation in a model system, we used flies collected from single populations of three different species of Drosophila and artificially selected them for resistance to the parasitoid wasp Leptopilina boulardi, and found that survival rates increased 3 to 30 fold within 6 generations. Resistance in all three species involves a large increase in the number of the circulating hemocytes that kill parasitoids. However, the different species achieve this in different ways, with D. melanogaster moving sessile hemocytes into circulation while the other species simply produce more cells. Therefore, the convergent evolution of the immune phenotype has different developmental bases. These changes are costly, as resistant populations of all three species had greatly reduced larval survival. In all three species resistance is only costly when food is in short supply, and resistance was rapidly lost from D. melanogaster populations when food is restricted. Furthermore, evolving resistance to L. boulardi resulted in cross-resistance against other parasitoids. Therefore, whether a population evolves resistance will depend on ecological conditions including food availability and the presence of different parasite species.

Predatory behavior of long-legged flies (Diptera:Dolichopodidae) and their potential negative effects on the parasitoid biological control agent of the Asian citrus psyllid (Hemiptera:Liviidae)

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Impact of biological control agents such as parasitoids can be improved by determining best times for release when predation pressures will be reduced. Large populations of long-legged predatory flies (Diptera: Dolichopodidae) impose heavy predation pressure on inundative releases of the parasitoid ...

Primeiro registro de Trichopria anastrephae, parasitoide de moscas-das-frutas, no Rio Grande do Sul First record of Trichopria anastrephae, parasitoid of fruit flies, in the Rio Grande do Sul State, Brazil

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Patrícia Postalli Cruz

2011-08-01

Full Text Available Existem poucas informações sobre as espécies nativas de himenópteros parasitoides de moscas-das-frutas da Região Neotropical, o que objetivou a realização do presente trabalho. Assim, coletas de goiaba (Psidium guajava L. foram realizadas de janeiro a março de 2009 na Área Experimental em Estudos de Produção Agroecológica (AEEPA da Universidade Federal de Pelotas, no município de Capão do Leão, Rio Grande do Sul. Os frutos foram levados ao laboratório, contados, pesados e acondicionados individualmente em potes plásticos contendo areia umedecida e telado na parte superior. Semanalmente, o substrato foi peneirado, os pupários recolhidos e acondicionados em placas de Petri com papel filtro umedecido com água destilada. Os pupários foram mantidos em sala climatizada (26±2°C, 60±10% de umidade relativa e 12h fotofase onde foram efetuadas observações semanais para verificar a emergência de moscas e/ou parasitoides e posterior identificação das espécies. Trichopria anastrephae Lima (Hymenoptera: Diapriidae foi obtida de pupários de Anastrepha fraterculus, com parasitismo de 5,8%.There is little information on native species of hymenopteran parasitoids of fruit flies from the Neotropical region. Collections of guava (Psidium guajava L. were conducted from January to March 2009 at the Experimental Area of Agroecological Production studies (AEEPA, Federal University of Pelotas, Capão do Leão, Rio Grande do Sul. Fruits were taken individually to the laboratory, counted, weighed and packaged in plastic pots containing moist sand and mesh on top. Weekly substrate was sieved, the pupae collected and placed in Petri dishes with filter paper moistened with distilled water. The pupae were placed in a room (26±2°C, 60±10% RH and 12h photophase where observations were made weekly to check the emergence of adult flies or parasitoids and subsequent species identification. Trichopria anastrephae Lima was obtained from Anastrepha

Temperature-dependent development of the parasitoid Tachinaephagus zealandicus on five forensically important carrion fly species.

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Voss, S C; Spafford, H; Dadour, I R

2010-06-01

The influences of temperature and host species on the development of the forensically important parasitoid Tachinaephagus zealandicus Ashmead (Hymenoptera: Encyrtidae) were studied at six constant temperatures in the range of 15-30 degrees C. T. zealandicus completed development successfully between 15 degrees C and 27 degrees C on five species of Calliphoridae, Calliphora albifrontalis Malloch, Calliphora dubia Macquart, Lucilia sericata Meigen, Chrysomya rufifacies Macquart and Chrysomya megacephala Fabricius. No adult parasitoids emerged from any of the host species reared at 30 degrees C. Temperature and host species significantly influenced development time, emergence success and progeny size. Development was significantly longer on Ch. megacephala and Ch. rufifacies at 18-24 degrees C and significantly longer on Ch. rufifacies and C. albifrontalis at 15 degrees C and 27 degrees C. Parasitoid emergence success was greatest at 21 degrees C, declined at the temperature extremes (15 degrees C and 27 degrees C) and was significantly lower on Ch. megacephala and Ch. rufifacies than on the three other host species. Progeny numbers per host pupa were highest at 21-24 degrees C, declined on either side of this temperature range and were significantly lower on L. sericata, Ch. rufifacies and Ch. megacephala than on either C. dubia or C. albifrontalis. An effect of host species on sex ratio was only observed at 27 degrees C, at which a higher proportion of T. zealandicus females emerged from Ch. megacephala and Ch. rufifacies than from the other host species. The thermal requirements for development (developmental thresholds, thermal constant, optimum temperature) of T. zealandicus in each host species were estimated using linear and non-linear models. Upper and lower developmental thresholds ranged between 29.90 degrees C and 31.73 degrees C, and 9.73 degrees C and 10.08 degrees C, respectively. The optimum temperature for development was estimated at between 25

Impact of terbufos on Cotesia flavipes, a parasitoid of Diatraea saccharalis

International Nuclear Information System (INIS)

Vargas, E.; Valverde, B.; Carazo, E.

1999-01-01

The effect of terbufos on larvae of Diatraea saccharalis and its parasitoid, Cotesia flavipes was evaluated in the laboratory. Bioassays were conducted to determine the dose response of non-parasitized larvae of D. saccharalis feeding on artificial diet contaminated with terbufos. From the dose-response curve based on larval fresh weight, sublethal doses ranging from 1.32 ppm to 108 ppm of terbufos were selected for further studying the effect of the insecticide on both species. Both parasitized and non-parasitized larvae were exposed to the selected sublethal doses of terbufos in the diet. Consumption of the insecticide by the host resulted in mortality of the parasitoid, increased length of its larval and pupal periods, decreased adult fresh weight and changes in sex proportions. These negative effects were more severe as the dose of the insecticide increased. D. saccharalis was also affected by terbufos; larvae showed abnormalities, the length of the larval and pupal periods increased and the proportion of the females was reduced. In a preliminary greenhouse bioassay, only traces of terbufos or its metabolites were found in treated maize plants and in tissue of D. saccharalis larvae feeding on them. (author)

Selectivity of organic compounds to the egg parasitoid Telenomus remus Nixon (Hymenoptera: Plastygastridae

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Débora Mello da Silva

2016-02-01

Full Text Available The selectivity of insecticides, bio-protective mixtures, and biofertilizers used in organic soybean production was evaluated for adults and pupae of the egg parasitoid Telenomus remus Nixon (Hymenoptera: Platygastridae under laboratory conditions in accordance with protocols proposed by the International Organization for Biological Control (IOBC. The products sprayed (dosage/180L of water were: 1 Baculovírus anticarsia 140x109 cpi; 2 Bacillus thuringiensis 16.8g; 3 Azadirachtin-A, azadirachtin-B, nimbina and salamina 9.6 ppm; 4 Rotenoids 4 liters; 5 Nitrogen 1.3%, phosphorus 3.0% and total organic carbon 8.0% 3 liters; 6 Sodium silicate 2% 4 liters; 7 Copper 7% + calcium 3.3% 1.8 liters; 8 Sulfur 20% + quicklime 10% 1.8 liters; 9 Chlorpyrifos 384g (positive control; 10 Distilled H2O (negative control. The results of experiments using pupae indicate that the organic compounds were classified as harmless (Class 1, except for the copper 7% + calcium 3.3% and sulfur 20% + quicklime 10%, which were classified as slightly harmful (Class 2. The contact bioassay with adults showed that all products were classified as harmless (Class 1. Only chlorpyrifos (384g was classified as harmful (Class 4 for both stages of the parasitoid. However, the use of this product (chlorpyrifos is not permitted in organic farming, and even in conventional farming is recommended, where feasible, replacement of the product with one compatible with the preservation of T. remus in nature. Thus, the products tested and used in organic soybean production were considered compatible with the parasitoid eggs of T. remus.

Introduced and Native Parasitoid Wasps Associated With Larch Casebearer (Lepidoptera: Coleophoridae) in Western Larch

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M. Miller-Pierce; D. C. Shaw; A. Demarco; P. T. Oester

2015-01-01

The larch casebearer [Coleophora laricella (Hubner)], a non-native insect, continues to impact western larch (Larix occidentalis Nutt.) through defoliation events in the Pacific Northwest. Biological control programs starting in the 1960s released seven species of parasitoid wasps to control C. laricella...

Effect of insecticides on mealybug destroyer (Coleoptera: Coccinellidae) and parasitoid Leptomastix dactylopii (Hymenoptera: Encyrtidae), natural enemies of citrus mealybug (Homoptera: Pseudococcidae).

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Cloyd, Raymond A; Dickinson, Amy

2006-10-01

In this study, we measured, under laboratory conditions, the direct and indirect effects of insecticides on mealybug destroyer, Cryptolaemus montrouzieri Mulsant (Coleoptera: Coccinellidae), and parasitoid Leptomastix dactylopii Howard (Hymenoptera: Encyrtidae), natural enemies of citrus mealybug, Planococcus citri (Risso) (Homoptera: Pseudococcidae). The adult stages of both natural enemies were exposed to sprays of the insecticides buprofezin, pyriproxyfen, flonicamid, acetamiprid, dinotefuran, and clothianidin at label-recommended rates to assess direct mortality after 24, 48, and 72 h, respectively. The effects of the insecticides on L. dactylopii parasitization rate and percentage of parasitoid emergence also were monitored using the label and 4x the recommended label rate. Dinotefuran was extremely detrimental to the adult parasitoid at the label rate with 100% mortality after 24 h. Buprofezin, pyriproxyfen, and flonicamid were not harmful to L. dactylopii when applied at the label rate. At 4x the recommended label rate, dinotefuran, acetamiprid, and clothianidin were all harmful to the parasitoid with 100% mortality 72 h after application. Both buprofezin and flonicamid were not toxic to L. dactylopii with 100% adult survival after 72 h. Pyriproxyfen and flonicamid, at both the label and 4x the recommended label rate, did not negatively affect L. dactylopii parasitization rate or percentage of parasitoid emergence. Acetamiprid, dinotefuran, and clothianidin were toxic to C. montrouzieri adults with 100% mortality after 48 h, whereas buprofezin, pyriproxyfen, and flonicamid demonstrated minimal (10-20% mortality after 48 h) harmful effects to the predator. Based on the results from our study, the indirect effects of the insect growth regulator (IGR) buprofezin were not decisive; however, the IGR pyriproxyfen and the insecticide flonicamid were not directly or indirectly harmful to the predator C. montrouzieri and parastioid L. dactylopii, indicating that

Side effects of some pesticides on the silverleaf whitefly’s parasitoid, Eretmocerus mundus Mercet (Hymenoptera: Aphelinidae under laboratory conditions

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Mustafa PORTAKALDALI

2015-12-01

Full Text Available The silverleaf whitefly, Bemisia tabaci (Gennadius (Hemiptera: Aleyrodidae is one of major pests in greenhouses vegetable cultivation. Eretmocerus mundus Mercet (Hymenoptera: Aphelinidae has an important role among effective parasitoids used in biological control of the silverleaf whitefly. Nondestructive or less destructive pesticides against this parasitoid should be preferred in the scope of biological control. For this goal, side effects of 8 plant protection products, including spinosad, pyriproxyfen, abamectin, emamectin benzoate, copper oxychloride, kresoxim-methyl+boscalid, dimethoate and propineb+cymoxanil on pupae and adults of E. mundus were tested in this laboratory study conducted according to IOBC standards. As a result, pesticides containing spinosad, abamectin and dimethoate were determined as highly destructive to pupae and adults of E. mundus, and pesticide containing emamectin benzoate was found as moderately harmful. As for propineb+cymoxanil, pyriproxyfen, kresoxim-methyl+boscalid and copper oxychloride, they were determined as ineffective on the parasitoid under laboratory conditions. These results obtained from experiments that were conducted under laboratory conditions also have to be supported by field or semi-field experiment’s results.

Pre-pupation behaviour of the aphid parasitoid Aphidius ervi (Haliday) and its consequences for pre-imaginal learning

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Gutiérrez-Ibáñez, Cristián; Villagra, Cristian A.; Niemeyer, Hermann M.

2007-07-01

Olfactory learning may occur at different stages of insect ontogeny. In parasitoid wasps, it has been mostly shown at adult emergence, whilst it remains controversial at pre-imaginal stages. We followed larval growth of the parasitoid wasp, Aphidius ervi Haliday, inside the host aphid, Acyrthosiphom pisum Harris, and characterised in detail the behaviour of third instar larvae. We found that just before cocoon spinning begins, the third instar larva bites a hole through the ventral side of the mummified aphid exoskeleton. We then evaluated whether this period of exposure to the external environment represented a sensitive stage for olfactory learning. In our first experiment, the third instar larvae were allowed to spin their cocoon on the host plant ( Vicia faba L.) surface or on a plastic plate covering the portion of the host plant exposed to the ventral opening. Recently emerged adults of the first group showed a preference for plant volatiles in a glass Y-olfactometer, whereas no preference was found in adults of the second group. In a second experiment, during the period in which the aphid carcass remains open or is being sealed by cocoon spinning, third instar larvae were exposed for 24 h to either vanilla odours or water vapours as control. In this experiment, half of the parasitoid larvae were later excised from the mummy to avoid further exposure to vanilla. Adult parasitoids exposed to vanilla during the larval ventral opening of the mummy showed a significant preference for vanilla odours in the olfactometer, regardless of excision from the mummy. The larval behaviour described and the results of the manipulations performed are discussed as evidences for the acquisition of olfactory memory during the larval stage and its persistence through metamorphosis.

Multiplex PCR in determination of Opiinae parasitoids of fruit flies, Bactrocera sp., infesting star fruit and guava.

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Shariff, S; Ibrahim, N J; Md-Zain, B M; Idris, A B; Suhana, Y; Roff, M N; Yaakop, S

2014-01-23

Malaysia is a tropical country that produces commercial fruits, including star fruits, Averrhoa carambola L. (Oxalidales: Oxalidaceae), and guavas, Psidium guajava L. (Myrtales: Myrtaceae). There is a high demand for these fruits, and they are planted for both local consumption and export purposes. Unfortunately, there has been a gradual reduction of these fruits, which has been shown to be related to fruit fly infestation, especially from the Bactrocera species. Most parasitic wasps (Hymenoptera: Braconidae: Opiinae) are known as parasitoids of fruit fly larvae. In this study, star fruits and guavas infested by fruit fry larvae were collected from the Malaysian Agricultural Research and Development Institute. The parasitized larvae were reared under laboratory conditions until the emergence of adult parasitoids. Multiplex PCR was performed to determine the braconid species using two mitochondrial DNA markers, namely cytochrome oxidase subunit I and cytochrome b. Two benefits of using multiplex PCR are the targeted bands can be amplified simultaneously using the same reaction and the identification process of the braconid species can be done accurately and rapidly. The species of fruit flies were confirmed using the COI marker. The results obtained from our study show that Diachasmimorpha longicaudata (Ashmead) (Hymenoptera: Braconidae), Fopius arisanus (Sonan), and Pysttalia incisi (Silvestri) were parasitoids associated with Bactrocera carambolae (Drew and Hancock) (Diptera: Tephritidae) infested star fruits. Fopius arisanus was also the parasitoid associated with Bactrocera papayae (Drew and Hancock) infested guavas. Maximum parsimony was been constructed in Opiinae species to compare tree resolution between these two genes in differentiating among closely related species. The confirmation of the relationship between braconids and fruit fly species is very important, recognized as preliminary data, and highly necessary in biological control programs. This is an

Biological Control of Tephritid Fruit Flies in Argentina: Historical Review, Current Status, and Future Trends for Developing a Parasitoid Mass-Release Program.

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Ovruski, Sergio M; Schliserman, Pablo

2012-09-14

In Argentina there are two tephritid fruit fly species of major economic and quarantine importance: the exotic Ceratitis capitata that originated from Southeast Africa and the native Anastrepha fraterculus. In recent years, the use of fruit fly parasitoids as biocontrol agents has received renewed attention. This increasing interest has recently led to the establishment of a program for the mass rearing of five million Diachasmimorpha longicaudata parasitoids per week in the BioPlanta San Juan facility, San Juan, Argentina. The first augmentative releases of D. longicaudata in Argentina are currently occurring on commercial fig crops in rural areas of San Juan as part of an integrated fruit fly management program on an area-wide basis. In this context, research is ongoing to assess the suitability of indigenous parasitoid species for successful mass rearing on larvae of either C. capitata or A. fraterculus. The purpose of this article is to provide a historical overview of the biological control of the fruit fly in Argentina, report on the strategies currently used in Argentina, present information on native parasitoids as potential biocontrol agents, and discuss the establishment of a long-term fruit fly biological control program, including augmentative and conservation modalities, in Argentina's various fruit growing regions.

Biological Control of Tephritid Fruit Flies in Argentina: Historical Review, Current Status, and Future Trends for Developing a Parasitoid Mass-Release Program

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Sergio M. Ovruski

2012-09-01

Full Text Available In Argentina there are two tephritid fruit fly species of major economic and quarantine importance: the exotic Ceratitis capitata that originated from Southeast Africa and the native Anastrepha fraterculus. In recent years, the use of fruit fly parasitoids as biocontrol agents has received renewed attention. This increasing interest has recently led to the establishment of a program for the mass rearing of five million Diachasmimorpha longicaudata parasitoids per week in the BioPlanta San Juan facility, San Juan, Argentina. The first augmentative releases of D. longicaudata in Argentina are currently occurring on commercial fig crops in rural areas of San Juan as part of an integrated fruit fly management program on an area-wide basis. In this context, research is ongoing to assess the suitability of indigenous parasitoid species for successful mass rearing on larvae of either C. capitata or A. fraterculus. The purpose of this article is to provide a historical overview of the biological control of the fruit fly in Argentina, report on the strategies currently used in Argentina, present information on native parasitoids as potential biocontrol agents, and discuss the establishment of a long-term fruit fly biological control program, including augmentative and conservation modalities, in Argentina’s various fruit growing regions.

The Role of Lipid Competition for Endosymbiont-Mediated Protection against Parasitoid Wasps in Drosophila

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Juan C. Paredes

2016-07-01

Full Text Available Insects commonly harbor facultative bacterial endosymbionts, such as Wolbachia and Spiroplasma species, that are vertically transmitted from mothers to their offspring. These endosymbiontic bacteria increase their propagation by manipulating host reproduction or by protecting their hosts against natural enemies. While an increasing number of studies have reported endosymbiont-mediated protection, little is known about the mechanisms underlying this protection. Here, we analyze the mechanisms underlying protection from parasitoid wasps in Drosophila melanogaster mediated by its facultative endosymbiont Spiroplasma poulsonii. Our results indicate that S. poulsonii exerts protection against two distantly related wasp species, Leptopilina boulardi and Asobara tabida. S. poulsonii-mediated protection against parasitoid wasps takes place at the pupal stage and is not associated with an increased cellular immune response. In this work, we provide three important observations that support the notion that S. poulsonii bacteria and wasp larvae compete for host lipids and that this competition underlies symbiont-mediated protection. First, lipid quantification shows that both S. poulsonii and parasitoid wasps deplete D. melanogaster hemolymph lipids. Second, the depletion of hemolymphatic lipids using the Lpp RNA interference (Lpp RNAi construct reduces wasp success in larvae that are not infected with S. poulsonii and blocks S. poulsonii growth. Third, we show that the growth of S. poulsonii bacteria is not affected by the presence of the wasps, indicating that when S. poulsonii is present, larval wasps will develop in a lipid-depleted environment. We propose that competition for host lipids may be relevant to endosymbiont-mediated protection in other systems and could explain the broad spectrum of protection provided.

Parasitoid inventarisation of European corn borer (Ostrinia nubilalis Hübner, 1796 and options for its biological control in Slovenia

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Jaka RAZINGER

2016-04-01

Full Text Available European corn borer (Ostrinia nubilalis (ECB is an important maize pest in central and northern Europe. Presently it is controlled by insecticides or biological agents such as Trichogramma brassicae in several European countries, excluding Slovenia, where the pest’s pressure is highly variable and no appropriate mechanization is available. Lessening the dependence on chemical pesticides is an integral part of the European Union’s agenda for agriculture. Mass release of Trichogramma spp. could be seen as a promising alternative for ECB control in countries with a highly fluctuating ECB pressure and no mechanization for insecticide applications. However, no records of naturally occurring hymenopteran parasitoids of ECB exist in Slovenia. To address this important under-researched topic and provide the expert basis for potential introduction of ECB egg parasitoids in Slovene maize production, a systematic inventarisation programme of ECB parasitoids was launched in 2010. Additionally, ECB flight was monitored in 2011 and 2012 at two locations in Slovenia: Jablje and Rakičan. In both locations two ECB generations  were observed. ECB was fist observed at the end of May in Rakičan. During the five years of the systematic survey we discovered two ECB parasitoid species. ECB egg masses were parasitized by Trichogramma brassicae, whereas ECB pupae were parasitized by Tycherus nigridens, with 6 or 7 % parasitation rate, respectively. T. nigridens represents a new taxon report for Slovenia. We conclude that there is a strong need for undertaking systematic surveys of natural enemies of agricultural pests.

Diet quality can play a critical role in defense efficacy against parasitoids and pathogens in the Glanville fritillary (Melitaea cinxia).

Science.gov (United States)

Laurentz, Minna; Reudler, Joanneke H; Mappes, Johanna; Friman, Ville; Ikonen, Suvi; Lindstedt, Carita

2012-01-01

Numerous herbivorous insect species sequester noxious chemicals from host plants that effectively defend against predators, and against parasitoids and pathogens. Sequestration of these chemicals may be expensive and involve a trade off with other fitness traits. Here, we tested this hypothesis. We reared Glanville fritillary butterfly (Melitaea cinxia L.) larvae on plant diets containing low- and high-levels of iridoid glycosides (IGs) (mainly aucubin and catalpol) and tested: 1) whether IGs affect the herbivore's defense against parasitoids (measured as encapsulation rate) and bacterial pathogens (measured as herbivore survival); 2) whether parasitoid and bacterial defenses interact; and 3) whether sequestration of the plant's defense chemicals incurs any life history costs. Encapsulation rates were stronger when there were higher percentages of catalpol in the diet. Implanted individuals had greater amounts of IGs in their bodies as adults. This suggests that parasitized individuals may sequester more IGs, increase their feeding rate after parasitism, or that there is a trade off between detoxification efficiency and encapsulation rate. Larval survival after bacterial infection was influenced by diet, but probably not by diet IG content, as changes in survival did not correlate linearly with the levels of IGs in the diet. However, M. cinxia larvae with good encapsulation abilities were better defended against bacteria. We did not find any life history costs of diet IG concentration for larvae. These results suggest that the sequestering of plant defense chemicals can help herbivorous insects to defend against parasitoids.

Development of microsatellite markers and estimation of inbreeding frequency in the parasitoid wasp Melittobia

NARCIS (Netherlands)

Abe, Jun; Pannebakker, Bart A.

2017-01-01

The parasitoid wasp Melittobia is an important insect for basic and applied biology. Specifically, their extremely female-biased sex ratios, which contrast to the prediction of pre-existing theories, are needed to be explained from the aspect of evolutionary biology. In this study, using

How to behave? : evolution of host-handling behaviour in the whitefly parasitoid Encarsia formosa

NARCIS (Netherlands)

Burger, J.M.S.

2002-01-01

The main aim of evolutionary ecology is to explain the adaptation of form, function and behaviour of organisms to their environment. In this thesis, I studied host-handling behaviour of the whitefly parasitoid Encarsia formosa form such an evolutionary point of view.

Susceptibility of the Parasitoid Phymastichus coffea LaSalle (Hymenoptera: Eulophidae) to Beauveria bassiana under laboratory conditions

International Nuclear Information System (INIS)

Castillo, Alfredo; Gomez, Jaime; Infante, Francisco; Vega, Fernando E.

2009-01-01

The coffee berry borer, Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae), is the most important coffee pest worldwide. Beauveria bassiana is a generalist entomopathogenic fungus widely used by coffee farmers to control this pest and Phymastichus coffea LaSalle (Hymenoptera: Eulophidae) is an African endo parasitoid of H. hampei adults, recently imported to several Latin American and Caribbean countries to aid in the coffee berry borer control. The objective of this study was to determine if B. bassiana is detrimental to P. coffea. The susceptibility of the parasitoid was evaluated in terms of adult survivorship, mean lethal concentration (LC 50 ), mean lethal time (LT 50 ), reproduction and immature mortality. The main effect of the fungus resulted in reduction of adult longevity and mortality of 100% for immature stages of this parasitoid. The LC 50 for adults was 0.11% equivalent to 9.53 x 10 7 conidia/ml of B. bassiana and a LT 50 of 29.4 h, equivalent to reduction of 22% of its normal longevity as an adult. P. coffea was capable of disseminating spores of B. bassiana to non-infected H. hampei adults, which could indirectly cause the death of its own progeny. These results could be valuable when considering the use of both organisms in the field, especially in an integrated pest management program. (author)

Impact of Abamectin on Anagrus nilaparvatae, An Egg Parasitoid of Nilaparvata lugens

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Edi Eko Sasmito

2017-12-01

Full Text Available Anagrus nilaparvatae (Hymenoptera: Mymaridae is an egg parasitoid potential for controlling the major pests on rice, the brown planthopper (Nilaparvata lugens [Hemiptera: Delphacidae].Abamectin is one of insecticides registered for N. lugens. The research was aimed to investigate the impact of contact application of abamectin on the parasitism level of A. nilaparvatae under laboratory conditions. Adults of A. nilaparvatae and the first instars as well as adults of N. lugens were exposed to the residue of abamection inside the test tube. A. nilaparvatae was much more susceptible to abamectin compared to N. lugens. Application of abamectin at the recommended concentration (22.78 ppm for 30 min caused 100% mortality, and it reduced to 85% when the concentration was decreased to 0.36 ppm. In contrast, the mortality for the first instar of N. lugens was only 15% at 22.78 and no mortality at 0.36 ppm. No N. lugens adults died even when they were exposed to 22.78 ppm. Furthermore, the parasitism test was conducted using 38 days after planting of IR-64 rice variety. Those plants were infested with 50 females of N. lugens for 2 days. A. nilaparvatae were exposed by contact to 0.02, 0.23, and 2.28 ppm of abamectin. The survivors were released to the rice plant containing eggs of N. lugens. Contact application of abamectin reduced parasitism level of A. nilaparvatae as much as 86.34, 70.01, and 28.43% with concentrations of 2.28 ppm, 0.23 and 0.02 ppm, respectively. In addition, the number of parasitoids emerged decreased with increasing concentration of abamectin. These results suggest that abamectin could be detrimental to A. nilaparvatae due to direct mortality, reduced the parasitism level, and decreased the number of progeny produced.   Intisari Anagrus nilaparvatae (Hymenoptera: Mymaridae merupakan salah satu parasitoid telur yang berpotensi untuk mengendalikan hama utama tanaman padi, wereng batang padi cokelat (Nilaparvata lugens [Hemiptera

Acoustic cloaking and transformation acoustics

International Nuclear Information System (INIS)

Chen Huanyang; Chan, C T

2010-01-01

In this review, we give a brief introduction to the application of the new technique of transformation acoustics, which draws on a correspondence between coordinate transformation and material properties. The technique is formulated for both acoustic waves and linear liquid surface waves. Some interesting conceptual devices can be designed for manipulating acoustic waves. For example, we can design acoustic cloaks that make an object invisible to acoustic waves, and the cloak can either encompass or lie outside the object to be concealed. Transformation acoustics, as an analog of transformation optics, can go beyond invisibility cloaking. As an illustration for manipulating linear liquid surface waves, we show that a liquid wave rotator can be designed and fabricated to rotate the wave front. The acoustic transformation media require acoustic materials which are anisotropic and inhomogeneous. Such materials are difficult to find in nature. However, composite materials with embedded sub-wavelength resonators can in principle be made and such 'acoustic metamaterials' can exhibit nearly arbitrary values of effective density and modulus tensors to satisfy the demanding material requirements in transformation acoustics. We introduce resonant sonic materials and Helmholtz resonators as examples of acoustic metamaterials that exhibit resonant behaviour in effective density and effective modulus. (topical review)

Trans-generational effects of mild heat stress on the life history traits of an aphid parasitoid.

Science.gov (United States)

Ismaeil, Ibrahim; Doury, Géraldine; Desouhant, Emmanuel; Dubois, Françoise; Prevost, Geneviève; Couty, Aude

2013-01-01

Temperature changes are common in nature and insects are particularly exposed and sensitive to such variations which can be potential stresses, ultimately affecting life history traits and overall fitness. Braconids have been widely used to study the effects of temperature on host-parasitoid interactions and the present work focused on the solitary endoparasitoid Aphidius ervi Haliday (Hymenoptera: Braconidae Aphidiidae), an efficient biological control agent commercially used against aphids such as the potato aphid Macrosiphum euphorbiae Thomas (Sternorrhyncha: Aphididae). Contrary to previous studies using heat shocks at extreme temperatures, we evaluated the effects of mild heat stresses by transferring young parasitoid adults from the constant temperature of 20°C to either a warm (25°C) or hot (28°C) temperature, for either 1 h or 48 h. Such treatments are consistent with situations commonly experienced by parasitoids when moved from their rearing conditions to greenhouses or field conditions. The effects were evaluated both on the heat stressed A. ervi adults (G0) (immediate effects) and on their first generation (G1) progeny (trans-generational effects). G0 wasps' mortality was significantly affected by the temperature in interaction with the duration of the stress. Longevity of G0 wasps surviving the heat stress was negatively affected by the temperature and females lived longer than males. Heat stress applied to A. ervi parents also had consequences on their G1 progeny whose developmental time, rates of mummification and percentage of parasitoid completing total development were negatively affected. Surprisingly, the egg load at emergence of the G1 female progeny was increased when their mothers had been submitted to a mild heat stress of 25°C or 28°C. These results clearly demonstrate trans-generational phenotypic plasticity, showing that adaptation to thermal stresses may be achieved via maternal effects. This study also sheds light on the complexity

Trans-generational effects of mild heat stress on the life history traits of an aphid parasitoid.

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Ibrahim Ismaeil

Full Text Available Temperature changes are common in nature and insects are particularly exposed and sensitive to such variations which can be potential stresses, ultimately affecting life history traits and overall fitness. Braconids have been widely used to study the effects of temperature on host-parasitoid interactions and the present work focused on the solitary endoparasitoid Aphidius ervi Haliday (Hymenoptera: Braconidae Aphidiidae, an efficient biological control agent commercially used against aphids such as the potato aphid Macrosiphum euphorbiae Thomas (Sternorrhyncha: Aphididae. Contrary to previous studies using heat shocks at extreme temperatures, we evaluated the effects of mild heat stresses by transferring young parasitoid adults from the constant temperature of 20°C to either a warm (25°C or hot (28°C temperature, for either 1 h or 48 h. Such treatments are consistent with situations commonly experienced by parasitoids when moved from their rearing conditions to greenhouses or field conditions. The effects were evaluated both on the heat stressed A. ervi adults (G0 (immediate effects and on their first generation (G1 progeny (trans-generational effects. G0 wasps' mortality was significantly affected by the temperature in interaction with the duration of the stress. Longevity of G0 wasps surviving the heat stress was negatively affected by the temperature and females lived longer than males. Heat stress applied to A. ervi parents also had consequences on their G1 progeny whose developmental time, rates of mummification and percentage of parasitoid completing total development were negatively affected. Surprisingly, the egg load at emergence of the G1 female progeny was increased when their mothers had been submitted to a mild heat stress of 25°C or 28°C. These results clearly demonstrate trans-generational phenotypic plasticity, showing that adaptation to thermal stresses may be achieved via maternal effects. This study also sheds light on

The role of contact chemoreception in the host location process of an egg parasitoid

NARCIS (Netherlands)

Iacovone, Alessia; French, Alice Sarah; Tellier, Frédérique; Cusumano, Antonino; Clément, Gilles; Gaertner, Cyril; Conti, Eric; Salerno, Gianandrea; Marion-Poll, Frédéric

2016-01-01

Taste allows insects to detect palatable or toxic foods, identify a mate, and select appropriate oviposition sites. The gustatory system strongly contributes to the survival and reproductive success of many species, yet it is rarely studied in insect parasitoids. In order to locate and assess a

Reproduction now or later: optimal host-handling strategies in the whitefly parasitoid Encarsia formosa

NARCIS (Netherlands)

Burger, J.M.S.; Hemerik, L.; Lenteren, van J.C.; Vet, L.E.M.

2004-01-01

We developed a dynamic state variable model for studying optimal host-handling strategies in the whitefly parasitoid Encarsia formosa Gahan (Hymenoptera: Aphelinidae). We assumed that (a) the function of host feeding is to gain nutrients that can be matured into eggs, (b) oogenesis is continuous and

Apomictic parthenogenesis in a parasitoid wasp Meteorus pulchricornis, uncommon in the haplodiploid order Hymenoptera.

Science.gov (United States)

Tsutsui, Y; Maeto, K; Hamaguchi, K; Isaki, Y; Takami, Y; Naito, T; Miura, K

2014-06-01

Although apomixis is the most common form of parthenogenesis in diplodiploid arthropods, it is uncommon in the haplodiploid insect order Hymenoptera. We found a new type of spontaneous apomixis in the Hymenoptera, completely lacking meiosis and the expulsion of polar bodies in egg maturation division, on the thelytokous strain of a parasitoid wasp Meteorus pulchricornis (Wesmael) (Braconidae, Euphorinae) on pest lepidopteran larvae Spodoptera litura (Fabricius) (Noctuidae). The absence of the meiotic process was consistent with a non-segregation pattern in the offspring of heterozygous females, and no positive evidence was obtained for the induction of thelytoky by any bacterial symbionts. We discuss the conditions that enable the occurrence of such rare cases of apomictic thelytoky in the Hymenoptera, suggesting the significance of fixed heterosis caused by hybridization or polyploidization, symbiosis with bacterial agents, and occasional sex. Our finding will encourage further genetic studies on parasitoid wasps to use asexual lines more wisely for biological control.

[Interaction of Metarhizium anisopliae (Metsch.) Sorok., Beauveria bassiana (Bals.) Vuill. and the parasitoid Oomyzus sokolowskii (Kurdjumov) (Hymenoptera: Eulophidae) with larvae of diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae)].

Science.gov (United States)

dos Santos, Hugo J G; Marques, Edmilson J; Barros, Reginaldo; Gondim, Manoel G C

2006-01-01

Chemical insecticides are broadly applied to control diamondback moth, Plutella xylostella (L.). Diamondback moth is a major pest of cruciferous worldwide, and resistance of this pest to insecticide has been often reported. Thus, this research investigated the interactions among the fungi Metarhizium anisopliae (Metsch.) Sorok., Beauveria bassiana (Bals.) Vuill., and the larval-pupal parasitoid Oomyzus sokolowskii (Kurdjumov) before and after application of the fungi on DBM larvae offered to the parasitoid. The experiment was carried out at 26+/-l degreeC, 75+/- 5% RH and 12h photophase using a completely randomized design, with eight treatments with six replications each. The isolates E9 of M. anisopliae and ESALQ 447 of B. bassiana, were used at the concentration of 10(7) conidia ml(-1). The results showed that M. anisopliae and B. bassiana reduced the parasitism of P. xylostella by O. sokolowskii. Additive effects were found on the mortality of P. xylostella with the different combinations among the fungi and parasitoid, except for the treatment B. bassiana inoculated 24h before exposition of the larvae to O. sokolowskii. The isolates were more efficacious when applied after exposition of the larvae to the parasitoid. The efficiency of O. sokolowskii was negatively influenced by the presence of the fungi, mainly when the fungi were applied 24h before diamondback's larvae were exposed to the parasitoid. The association of the fungi with the parasitoid presents potential to be tested in field. The use of these natural enemies in the integrated management of P. xylostella may economically improve the cabbage productive system, especially for organic farming.

Biological control of olive fruit fly (Diptera: Tephritidae) by releases of Psyttalia cf. concolor (Hymenoptera: Braconidae) in California, parasitoid longevity in presence of the host, and host status of Walnut Husk Fly

Energy Technology Data Exchange (ETDEWEB)

Yokoyama, Victoria Y., E-mail: vyokoyama@fresno.ars.usda.go [U.S. Department of Agriculture (USDA/ARS/SJVASC), Parlier, CA (United States). Agricultural Research Service. Subtropical Horticulture Research Station; Rendon, Pedro A., E-mail: prendon@aphisguate.co [U.S. Department of Agriculture (USDA/APHIS), Guatemala City (Guatemala). Center for Plant Health Science and Technology. Animal and Plant Health Inspection.; Sivinski, John, E-mail: jsivinski@gainesville.usda.ufl.ed [U.S. Department of Agriculture (USDA/ARS/CMAVE), Gainesville, FL (United States). Agricultural Research Service. Center for Medical, Agricultural and Veterinary Entomology

2006-07-01

The larval parasitoid, Psyttalia cf. concolor, collected from tephritids infesting coffee in Kenya and reared on Mediterranean fruit fly, Ceratitis capitata Weidemann, in Guatemala by USDA-APHIS, PPQ, was imported into California for biological control of olive fruit fly, Bactrocera oleae (Gmelin), in olives, Olea europaea. Free releases of the parasitoids were made in olive trees infested with olive fruit fly at a coastal and inland valley location during the fall and early winter of 2005. The relative humidity during the releases was significantly higher at the coastal location. Mean percentage parasitism ranged from 0.5 to 4 and 1.5 to 30 at the coastal and inland valley locations respectively, based on same season recovery of the F1 generation. One parasitoid was found in infested olives in the next crop of the following year in San Jose. Survival of the parasitoid in the greenhouse in the presence of olive fruit fly infested olives was not significantly different than in the presence of non-infested olives. The greatest number of progeny was produced from female parasitoids that were 12-16 d old. In laboratory tests, a few individuals of the parasitoid successfully completed one life cycle in walnut husk fly, Rhagoletis completa Cresson, infested English walnuts, Juglans regia L. (author)

Biological control of olive fruit fly (Diptera: Tephritidae) by releases of Psyttalia cf. concolor (Hymenoptera: Braconidae) in California, parasitoid longevity in presence of the host, and host status of Walnut Husk Fly

International Nuclear Information System (INIS)

Yokoyama, Victoria Y.; Rendon, Pedro A.; Sivinski, John

2006-01-01

The larval parasitoid, Psyttalia cf. concolor, collected from tephritids infesting coffee in Kenya and reared on Mediterranean fruit fly, Ceratitis capitata Weidemann, in Guatemala by USDA-APHIS, PPQ, was imported into California for biological control of olive fruit fly, Bactrocera oleae (Gmelin), in olives, Olea europaea. Free releases of the parasitoids were made in olive trees infested with olive fruit fly at a coastal and inland valley location during the fall and early winter of 2005. The relative humidity during the releases was significantly higher at the coastal location. Mean percentage parasitism ranged from 0.5 to 4 and 1.5 to 30 at the coastal and inland valley locations respectively, based on same season recovery of the F1 generation. One parasitoid was found in infested olives in the next crop of the following year in San Jose. Survival of the parasitoid in the greenhouse in the presence of olive fruit fly infested olives was not significantly different than in the presence of non-infested olives. The greatest number of progeny was produced from female parasitoids that were 12-16 d old. In laboratory tests, a few individuals of the parasitoid successfully completed one life cycle in walnut husk fly, Rhagoletis completa Cresson, infested English walnuts, Juglans regia L. (author)

Acanthopria and Mimopriella parasitoid wasps (Diapriidae) attack Cyphomyrmex fungus-growing ants (Formicidae, Attini)

Science.gov (United States)

Fernández-Marín, Hermógenes; Zimmerman, Jess K.; Wcislo, William T.

2006-01-01

New World diapriine wasps are abundant and diverse, but the biology of most species is unknown. We provide the first description of the biology of diapriine wasps, Acanthopria spp. and Mimopriella sp., which attack the larvae of Cyphomyrmex fungus-growing ants. In Puerto Rico, the koinobiont parasitoids Acanthopria attack Cyphomyrmex minutus, while in Panama at least four morphospecies of Acanthopria and one of Mimopriella attack Cyphomyrmex rimosus. Of the total larvae per colony, 0 100% were parasitized, and 27 70% of the colonies per population were parasitized. Parasitism rate and colony size were negatively correlated for C. rimosus but not for C. minutus. Worker ants grasped at, bit, and in some cases, killed adult wasps that emerged in artificial nests or tried to enter natural nests. Parasitoid secondary sex ratios were female-biased for eclosing wasps, while field collections showed a male-biased sex ratio. Based on their abundance and success in attacking host ants, these minute wasps present excellent opportunities to explore how natural enemies impact ant colony demography and population biology.

Developing Cotton IPM by Conserving Parasitoids and Predators of The Main Pest

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Nurindah Nurindah

2015-09-01

Full Text Available On early development of intensive cotton program, insect pests were considered as an important aspect in cotton cultivation, so that it needed to be scheduled sprays. The frequency of sprays was 7 times used 12L of chemical insecticides per hectare per season. Development of cotton IPM was emphasized on non-chemical control methods through optimally utilize natural enemies of the cotton main pests (Amrasca biguttulla (IshidaHelicoverpa armigera (Hübner. Conservation of parasitoids and predators by providing the environment that support their population development is an act of supporting the natural enemies as an effective biotic mortality factor of the insect pests. The conservation could be done by improving the plant matter and cultivation techniques that include the use of resistant variety to leafhopper, intercropping cotton with secondary food plants, mulch utilization, using action threshold that considered the presence of natural enemies, and application of botanical insecticides, if needed. Conservation of parasitoids and predators in cotton IPM could control the insect pests without any insecticide spray in obtaining the production of cotton seed. As such, the use of IPM method would increase farmers’ income.

Use of pupal parasitoids as biological control agents of filth flies on equine facilities

Science.gov (United States)

House flies, Musca domestica L., and stable flies, Stomoxys calcitrans (L.), (Diptera: Muscidae), are common pests on horse farms. The use of pupal parasitoids as biological control agents for filth flies is becoming more popular on equine facilities; however, there is a lack of information on the e...

Reproduction now or later: optimal host-hanling strategies in the whitefly parasitoid Encarsia formosa

NARCIS (Netherlands)

Burger, J.S.M.; Hemerik, L.; Van Lenteren, J.C.; Vet, L.E.M.

2004-01-01

We developed a dynamic state variable model for studying optimal host-handling strategies in the whitefly parasitoid Encarsia formosa Gahan (Hymenoptera: Aphelinidae). We assumed that (a) the function of host feeding is to gain nutrients that can be matured into eggs, (b) oögenesis is continuous and

Parasitoidism of Chalcidid wasps (Hymenoptera, Chalcididae on Philornis sp. (Diptera, Muscidae

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M. S. Couri

Full Text Available Philornis Meinert larvae are known as parasites of birds, with coprophagous, semi-hematophagous or hematophagous habits. Biological data of the larvae of the fifty described species are still scarcely known. Here we describe some aspects of the parasitism of a species of Philornis on Thalurania glaucopis Gmelin (Trochilidae and record two species of Chalcididae (Hymenoptera parasitoids, Conura annulifera (Walker, 1864 and Brachymeria podagrica (Fabricius, 1787, reared from Philornis puparia.

Functional response and life history parameters of Apanteles taragamae, a larval parasitoid of Maruca vitrata

NARCIS (Netherlands)

Dannon, A.E.; Tamò, M.; Huis, van A.; Dicke, M.

2010-01-01

The legume pod borer Maruca vitrata Fabricius (Lepidoptera: Crambidae) is a serious pest of cowpea in West-Africa. The parasitoid Apanteles taragamae Viereck (Hymenoptera: Braconidae) that originates from Taiwan is a potential candidate for biological control of M. vitrata. We investigated under

Aphid parasitoids sampled by Malaise traps in the National parks of Thailand (Hymenoptera, Braconidae, Aphidiinae)

Czech Academy of Sciences Publication Activity Database

Starý, Petr; Sharkey, M.; Hutacharern, C.

2008-01-01

Roč. 41, 1-2 (2008), s. 37-43 ISSN 0049-3589 Grant - others:Framework of Research Funded by the NSF grant(US) DEB 0542864 Institutional research plan: CEZ:AV0Z50070508 Keywords : aphids * parasitoids * biodiversity Subject RIV: EH - Ecology, Behaviour

Parasitization of commercially available parasitoid species against the lettuce aphid, Nasonovia ribisnigri (Hemiptera: Aphididae).

Science.gov (United States)

Shrestha, G; Skovgård, H; Enkegaard, A

2014-12-01

The lettuce aphid, Nasonovia ribisnigri (Mosley), is an economically important pest of lettuce worldwide. Little documentation exists for the control efficacy of aphid parasitoids against N. ribisnigri. This laboratory study evaluated three commercially available parasitoid species: Aphidius colemani (Viereck), Lysiphlebus testaceipes (Cresson), and Aphelinus abdominalis (Dalman) for their mortality impact on N. ribisnigri. The green peach aphid Myzus persicae (Sulzer) was included as a reference aphid. The study showed that A. abdominalis successfully parasitized 39 and 13% of the offered N. ribisnigri and M. persicae, respectively, within a 24-h exposure period. In contrast, none of the lettuce aphids exposed to Ap. colemani or L. testaceipes were successfully parasitized, whereas 60 and 3.5% of M. persicae, respectively, were successfully parasitized within a 6-h exposure period. Lettuce aphid mortality due to incomplete parasitization was 26 and 31% when exposed to Ap. colemani and L. testaceipes, respectively, with corresponding values for M. persicae being 5 and 10%, respectively. Mortality as a result of incomplete parasitization when aphids were exposed to A. abdominalis was low for both aphid species. The total mortality inflicted by A. abdominalis within a 24-h exposure period was 51% for the lettuce aphids and significantly less (19%) for green peach aphids. In contrast, Ap. colemani inflicted a higher mortality in M. persicae (65%) compared with N. ribisnigri (26%) within a 6-h exposure period. L. testaceipes caused a greater mortality in N. ribisnigri as compared with M. persicae. This study concludes that A. abdominalis has the potential to be used against N. ribisnigri in inoculative biocontrol programs as compared with the other parasitoid species based on successful parasitization.

Aphids and their parasitoids (Hym., Braconidae: Aphidiinae) asociated with medicinal plants in Iran

Czech Academy of Sciences Publication Activity Database

Talebi, A. A.; Rakhshani, E.; Fathipour, Y.; Starý, Petr; Tomanović, Ž.; Rajabi-Mazhar, N.

2009-01-01

Roč. 3, č. 2 (2009), s. 205-219 ISSN 1995-0748 R&D Projects: GA AV ČR IBS5007102 Grant - others:University of Zabol(IR) No. 86-19; The Serbian Ministry of Science(CS) 143006 Institutional research plan: CEZ:AV0Z50070508 Keywords : medicinal plants * aphid parasitoids * Aphidiinae Subject RIV: EH - Ecology, Behaviour

New species and a review of aphid parasitoids of Madagascar (Hym., Braconidae, Aphidiinae)

Czech Academy of Sciences Publication Activity Database

Starý, Petr

2005-01-01

Roč. 37, č. 2 (2005), s. 1711-1718 ISSN 0253-116X R&D Projects: GA AV ČR(CZ) IBS5007102 Grant - others:National Science Foundation(US) DEB-0072713; National Science Foundation(US) DEB-0344731 Institutional research plan: CEZ:AV0Z50070508 Keywords : aphids * parasitoids * sub - Saharan Africa Sub ject RIV: EG - Zoology

Interactions between Bacillus thuringiensis and parasitoids of late-instar larvae of the spruce budworm (Lepidoptera: Tortricidae)

NARCIS (Netherlands)

Schoenmaker, A.; Cusson, M.; Frankenhuyzen, van K.

2001-01-01

We investigated interactions between Bacillus thuringiensis Berliner var. kurstaki and parasitoids that attack late instars of the eastern spruce budworm, Choristoneura fumiferana (Clemens). In a petri-dish arena, females of Tranosema rostrale rostrale (Brishke) (Hymenoptera: Ichneumonidae) were

Complex interactions envolving a gall midge Myrciamyia maricaensis Maia (Diptera, Cecidomyiidae, phytophagous modifiers and parasitoids

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Fernando Fortunato Faria Ferraz

2003-09-01

Full Text Available Myrciamyia maricaensis Maia, 1995 (Diptera, Cecidomyiidae induces a gall in lateral and apical shoots in the plant Myrcia lundiana Kiaersk (Myrtaceae which is used and modified by two eulophid wasps species. In both cases the gall former species suffer high rate of attack exceeding the importance of parasitoid species as mortality factors. In this study these interactions are described and their effects as mortality of gall former. The intensity of occurrence of the two eulophid species as modifiers and of microhymenopteran parasitoids, and the relative importance of these species as mortality agents of the M. maricaensis larvae is compared. This comparison reveals that two modifiers species found in the gall tissue modification causing the death of the M. maricaensis larva and it is a more important factor of mortality than the cecidomyiid larva parasitism. The fluctuation of the number of each type of gall along the year was monitored in the research field and confirmed in numerical and in synchronic terms of occurrence of the galls; the importance of the species of the gall modifier eulophids, particularly one of these species, as factors of mortality of the M. maricaensis larvae and justified our comparing the relationship between these species and M. maricaensis as similar to the parasitoid-host relationship. The gall shape modification by one of the eulophids allows the occurrence of other inquiline insect species, what means that this gall modification becomes it more heterogeneous and allows the increase of the species richness to the system.

Platigástridos (Hymenoptera: Platygastridae parasitoides de Pentatomidae en Córdoba. Caracterización de las masas de huevos parasitoidizadas y aspectos biológicos

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Norma LA PORTA

2013-01-01

Full Text Available Se caracterizan las masas de huevos parasitoidizadas de pentatómidos per - tenecientes a cinco especies, cuatro fitófagas y una depredadora. Además, se analizan aspectos biológicos de esas oviposturas (abundancia y parasitoidismo y de sus para - sitoides (proporción sexual y emergencia: cinco especies de microhimenópteros plati - gástridos pertenecientes a los géneros Trissolcus Ashmead, Telenomus Haliday y Gryon Haliday . El análisis de las masas de huevos de pentatómidos en el campo apor ta indi - cadores exomorfológicos para determinar si están o no parasitoidizadas y, en algunos casos, conocer la especie de parasitoide emergente. Los altos niveles de parasitoidismo registrados en ambos sitios muestreados –Marcos Juárez y zona periurbana de Córdoba, sugieren que los parasitoides oófagos inciden de manera importante en las poblaciones de hemípteros presentes en el cultivo de soja. Las especies parasitoides mostraron una proporción de sexos marcadamente sesgada hacia las hembras, con un comportamiento similar respecto a cada huésped con el que interactuaron. Los porcentajes de emergencia resultaron más variables dependiendo de la especie parasitoide, del huésped y del sitio. El multiparasitoidismo fue registrado en todas las especies con excepción de Nezara viridula L. Telenomus podisi Ashmead fue el parasitoide común en las combinaciones observadas, resultando T. podisi-Trissolcus urichi Crawford la más frecuente.

Genetics of female functional virginity in the Parthenogenesis-Wolbachia infected parasitoid wasp Telenomus nawai (Hymenoptera: Scelionidae)

NARCIS (Netherlands)

Jeong, G.S.; Stouthamer, R.

2005-01-01

A lepidopteran egg parasitoid species Telenomus nawai consists of two distinct populations with different reproductive modes. One is a completely thelytokous population consisting of females only, whereas the other displays arrhenotokous reproduction where fertilized eggs develop into diploid

A review of insect parasitoids associated with Lobesia botrana (Denis & Schiffermüller, 1775) in Italy. 1. DipteraTachinidae and HymenopteraBraconidae (Lepidoptera, Tortricidae).

Science.gov (United States)

Scaramozzino, Pier Luigi; Loni, Augusto; Lucchi, Andrea

2017-01-01

This paper is aimed to summarize the information available on the parasitoid complex of the European Grapevine Moth (EGVM), Lobesia botrana (Denis & Schiffermüller, 1775) (Lepidoptera Tortricidae) in Italy. The list is the result of the consultation of a vast bibliography published in Italy for almost two hundred years, from 1828 to date. This allowed the clarification and correction of misunderstandings and mistakes on the taxonomic position of each species listed. In Italy the complex of parasitoids detected on EGVM includes approximately 90 species belonging to ten families of Hymenoptera (Braconidae, Ichneumonidae, Chalcididae, Eulophidae, Eupelmidae, Eurytomidae, Pteromalidae, Torymidae, Trichogrammatidae, and Bethylidae) and one family of Diptera (Tachinidae). This paper deals with EGVM parasitoids of the families Tachinidae (Diptera) and Braconidae (Hymenoptera). Only two species of Tachinidae are associated to EGVM larvae in Italy, Actia pilipennis (Fallen) and Phytomyptera nigrina (Meigen), whereas the record of Eurysthaea scutellaris (Robineau-Desvoidy) is doubtful. Moreover, 21 species of Braconidae are reported to live on EGVM, but, unfortunately, eight of them were identified only at generic level. Bracon mellitor Say has been incorrectly listed among the parasitoids of Lobesia botrana . Records concerning Ascogaster rufidens Wesmael, Meteorus sp., Microgaster rufipes Nees, and Microplitis tuberculifer (Wesmael) are uncertain.

A review of insect parasitoids associated with Lobesia botrana (Denis & Schiffermüller, 1775 in Italy. 1. Diptera Tachinidae and Hymenoptera Braconidae (Lepidoptera, Tortricidae

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Pier Luigi Scaramozzino

2017-01-01

Full Text Available This paper is aimed to summarize the information available on the parasitoid complex of the European Grapevine Moth (EGVM, Lobesia botrana (Denis & Schiffermüller, 1775 (Lepidoptera Tortricidae in Italy. The list is the result of the consultation of a vast bibliography published in Italy for almost two hundred years, from 1828 to date. This allowed the clarification and correction of misunderstandings and mistakes on the taxonomic position of each species listed. In Italy the complex of parasitoids detected on EGVM includes approximately 90 species belonging to ten families of Hymenoptera (Braconidae, Ichneumonidae, Chalcididae, Eulophidae, Eupelmidae, Eurytomidae, Pteromalidae, Torymidae, Trichogrammatidae, and Bethylidae and one family of Diptera (Tachinidae. This paper deals with EGVM parasitoids of the families Tachinidae (Diptera and Braconidae (Hymenoptera. Only two species of Tachinidae are associated to EGVM larvae in Italy, Actia pilipennis (Fallen and Phytomyptera nigrina (Meigen, whereas the record of Eurysthaea scutellaris (Robineau-Desvoidy is doubtful. Moreover, 21 species of Braconidae are reported to live on EGVM, but, unfortunately, eight of them were identified only at generic level. Bracon mellitor Say has been incorrectly listed among the parasitoids of L. botrana. Records concerning Ascogaster rufidens Wesmael, Meteorus sp., Microgaster rufipes Nees, and Microplitis tuberculifer (Wesmael are uncertain.

Influence of age and diet on the performance of Cephalonomia stephanoderis (Hymenoptera, Bethylidae a parasitoid of the coffee berry borer, Hypothenemus hampei (Coleoptera, Curculionidae

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Jaime Gómez

2012-03-01

Full Text Available The importance of age and feeding on the performance of Cephalonomia stephanoderis (Hymenoptera, Bethylidae, a parasitoid of the coffee berry borer, Hypothenemus hampei (Coleoptera, Curculionidae was investigated in the laboratory. Groups of female parasitoids were subject to the following treatments: a group fed during one, five and ten days after emergence of adults with coffee borer larvae; another group fed only with honey solution during five days after emergence; and as a control, a third group was kept without food for five days. At the end of each treatment, survivorship, parasitoid activity (walking and flying capacity in an arena, search capacity for finding coffee borer-infested berries, host feeding and oviposition (on immature hosts, were assessed. Unfed females showed a significant decrease in survivorship compared to individuals that were fed. The type of meal (insects or honey did not significantly influence parasitoid activity, search and oviposition capacities. Females fed with honey solution significantly consumed less immature coffee borers. Younger females (one day old walked and flew out of the arena significantly faster than older ones (5 and 10 days old. Implications of these results are discussed on the performance of C. stephanoderis as a biological control agent of the coffee berry borer.

Increase of acceptability period of Musca domestic l., 1758 (diptera: muscidae) pupae, irradiated by gamma radiation as host of the pupal parasitoid Spalangia endius, Walker, 1839 (hymenoptera: pteromalidae)

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Itepan, Natanael M., E-mail: nmitepan@ifsp.edu.br [Instituto Federal de Sao Paulo (IFSP), Piracicaba, SP (Brazil); Itepan, Sara E.D.Z., E-mail: sarazenitepan@ig.com.br [Universidade de Sao Paulo (FFCLRP/USP), Ribeirao Preto, SP (Brazil). Faculdade de Filosofia Ciencias e Letras; Arthur, Valter, E-mail: arthur@cena.usp.br [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil)

2013-07-01

This experiment was carried out in Biological Control of Domestic Fly 'Eduardo Hiroshi Mizumoto' Laboratory at Entomology and Acarology Department (LEA/ESALQ/USP) and in Food Irradiation and Radioentomology Laboratory (LIARE/CENA/USP). The gamma radiation source used was a Co-60 irradiator model Gammabeam-650 of the Atomic Energy of Canada Ltd. whose activity in the beginning of the experiments was 9.8x10{sup 13} Bq. (2,644 Ci). The lots of pupae of Musca domestic L., 1758 and the parasitoid Spalangia endius Walker, 1839 had been kept in acclimatized room with 25 ± 2 deg C of temperature and 70 ± 5% of relative humidity. This experiment was designed to investigate if the non-viabilization M. domestic pupae, using gamma radiation, could build up the acceptability period as host of the pupal parasitoid S. endius. At these age intervals, the dose to prevent adult emergence was 25, 220, 360 and 520 Gy respectively. The 1, 2, 3 and 4 days old pupae were irradiated (dose rate: 1,510 Gy/hr) and exposed to the parasitoid S. endius at a proportion of one female parasitoid to five housefly pupae, during different periods after the irradiation. The results allow us to conclude that irradiation increase the acceptability period of the housefly pupae by the parasitoid. The best age to irradiate the housefly pupae was one day. (author)

Increase of acceptability period of Musca domestic l., 1758 (diptera: muscidae) pupae, irradiated by gamma radiation as host of the pupal parasitoid Spalangia endius, Walker, 1839 (hymenoptera: pteromalidae)

International Nuclear Information System (INIS)

Itepan, Natanael M.; Itepan, Sara E.D.Z.

2013-01-01

This experiment was carried out in Biological Control of Domestic Fly 'Eduardo Hiroshi Mizumoto' Laboratory at Entomology and Acarology Department (LEA/ESALQ/USP) and in Food Irradiation and Radioentomology Laboratory (LIARE/CENA/USP). The gamma radiation source used was a Co-60 irradiator model Gammabeam-650 of the Atomic Energy of Canada Ltd. whose activity in the beginning of the experiments was 9.8x10 13 Bq. (2,644 Ci). The lots of pupae of Musca domestic L., 1758 and the parasitoid Spalangia endius Walker, 1839 had been kept in acclimatized room with 25 ± 2 deg C of temperature and 70 ± 5% of relative humidity. This experiment was designed to investigate if the non-viabilization M. domestic pupae, using gamma radiation, could build up the acceptability period as host of the pupal parasitoid S. endius. At these age intervals, the dose to prevent adult emergence was 25, 220, 360 and 520 Gy respectively. The 1, 2, 3 and 4 days old pupae were irradiated (dose rate: 1,510 Gy/hr) and exposed to the parasitoid S. endius at a proportion of one female parasitoid to five housefly pupae, during different periods after the irradiation. The results allow us to conclude that irradiation increase the acceptability period of the housefly pupae by the parasitoid. The best age to irradiate the housefly pupae was one day. (author)

Distributional patterns of fall armyworm parasitoids in a corn field and pasture field in Florida

Science.gov (United States)

An assessment of parasitoids and their selective patterns among Spodoptera frugiperda corn and rice host strains was performed from August 2008-August 2010 in a corn crop and a grass pasture in northern Florida under different seasonal conditions (spring and fall). Sentinel larvae from our laborator...

Toxicity of Piper aduncum (Piperaceae) Essential Oil Against Euschistus heros (F.) (Hemiptera: Pentatomidae) and Non-Effect on Egg Parasitoids.

Science.gov (United States)

Turchen, L M; Piton, L P; Dall'Oglio, E L; Butnariu, A R; Pereira, M J B

2016-10-01

Plant essential oils have been recognized as significant natural resources for insecticides. Herein, we have assessed the toxicity of the essential oil of Piper aduncum (Piperaceae) against Euschistus heros (F.) (Hemiptera: Pentatomidae), a key soybean pest in Neotropical America. In addition, we have assessed its effect on the performance of egg parasitoids. The essential oil was obtained from the leaves of P. aduncum via hydrodistillation. Subsequently, bioassays of the concentration response to eggs (contact and immersion methods), nymphs, and adults (topical application) were conducted, to assess the lethal effects on the stink bug. We also evaluated the performance of parasitism and adult emergence of egg parasitoids, when the host eggs were treated with essential oil. In the egg bioassay, both exposure methods were efficient for unviable eggs (immersion LC 50  = 15.64 mg mL -1 ; contact LC 50  = 21.29 mg mL -1 ), with the highlight on the immersion method. The bioassay with nymphs indicated a higher toxicity of essential oil, with lower concentrations (LC 50  = 11.37 mg mL -1 ) being required to cause the death of insects. For adults, a reduction in survival of insects was observed, and consequently, there was a reduction in the number of individuals in the next generation. Although the essential oil was toxic to E. heros, it exhibited lower toxicity for egg parasitoids, as there was no effect on parasitism and the emergence of wasps. We discuss likely explanations for such selectivity. In summary, we found that the essential oil was promising for the control of E. heros, because it caused deleterious effects at all development stages of the stink bug and had no effect on parasitism and emergence of the egg parasitoids, which suggested compatibility with biological control.

Identification and evaluation of a new entomopathogenic fungal strain against Riptortus pedestris (Hemiptera: Alydidae) and its two egg parasitoids

Science.gov (United States)

Lim, Un Taek

2018-01-01

A strain (ARP14) of the entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin was isolated from field-collected Riptortus pedestris (Fabricius) (Hemiptera: Alydidae). The lethal median concentration of the ARP14 strain was compared with that of a commercialized strain (GHA) of the same fungus against R. pedestris and its two egg parasitoids, Ooencyrtus nezarae Ishii (Hymenoptera: Encyrtidae) and Gryon japonicum (Ashmead) (Hymenoptera: Platygastridae). Mortality and mycosis rates were evaluated after exposure to five concentrations of the fungus, i.e., 1×109, 1×108, 1×107, 1×106, and 1×105 conidia/mL, using a glass scintillation vial as an exposure arena in 25.0 ± 0.5°C and 93.7 ± 2.9% RH. The lethal median concentrations (LC50) for 2nd and 4th instar nymphs, and adults of R. pedestris were not significantly different between the two strains of B. bassiana. However, the mycosis rate of ARP14 was 1.3 and 1.8 times higher than that of the GHA strain in 4th instar nymphs and adult females of R. pedestris, respectively, at the 1×108 conidia/mL concentration. More interestingly, the mycosis rates at 1×108 conidia/mL concentration in the parasitoids G. japonicum and O. nezarae were much lower in the ARP14 strain (15.0 and 0%) than in the GHA strain (73.3 and 66.0%), respectively, suggesting that the B. bassiana strain ARP14 is less virulent to these parasitoids than the commercially available strain. Our results suggest that B. bassiana ARP14 may be a potential new biopesticide against R. pedestris with fewer negative effects on beneficial parasitoids than currently available options. PMID:29664929

Brood size and sex ratio in response to host quality and wasp traits in the gregarious parasitoid Oomyzus sokolowskii (Hymenoptera: Eulophidae

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Xianwei Li

2017-01-01

Full Text Available This laboratory study investigated whether the larval-pupal parasitoid Oomyzus sokolowskii females adjust their brood size and sex ratio in response to body size and stage of Plutella xylostella larval hosts, as well as to their own body size and the order of oviposition. These factors were analyzed using multiple regression with simultaneous entry of them and their two-way interactions. Parasitoids brood size tended to increase with host body size at parasitism when the 4th instar larval host was attacked, but did not change when the 2nd and 3rd instar larvae were attacked. Parasitoids did not vary in brood size according to their body size, but decreased with their bouts of oviposition on a linear trend from 10 offspring adults emerged per host in the first bout of oviposition down to eight in the third. Parasitoid offspring sex ratio did not change with host instar, host body weight, wasp body size, and oviposition bout. Proportions of male offspring per brood were from 11% to 13% from attacking the 2nd to 4th instar larvae and from 13% to 16% across three successive bouts of oviposition, with a large variation for smaller host larvae and wasps. When fewer than 12 offspring were emerged from a host, one male was most frequently produced; when more than 12 offspring were emerged, two or more males were produced. Our study suggests that O. sokolowskii females may optimize their clutch size in response to body size of mature P. xylostella larvae, and their sex allocation in response to clutch size.

Biología de Eretmocerus mundus (Hymenoptera: Aphelinidae, parasitoide del complejo Bemisia tabaci (Homoptera: Aleyrodidae, en condiciones de laboratorio Biology of Eretmocerus mundus (Hymenoptera: Aphelinidae, parasitoid of Bemisia tabaci complex (Homoptera: Aleyrodidae under laboratory conditions

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Yerlin Chacón Castro

2010-06-01

Full Text Available La estimación de los atributos biológicos de un enemigo natural, previa a su empleo en el campo, constituye un aspecto de importancia en todo proyecto de control biológico. El objetivo de este trabajo fue evaluar los principales parámetros biológicos de Eretmocerus mundus Mercet, parasitoide de Bemisia tabaci (Gennadius, bajo condiciones de laboratorio.La emergencia del adulto, longevidad y fecundidad de la hembra, proporción sexual de la descendencia, tasa intrínseca de crecimiento poblacional (r m, tasa neta de reproducción (Ro y tiempo generacional (T; se estimaron mediante la técnica de tabla de vida y fecundidad, utilizando el pimiento (Capsicum annuum L. y el tomate (Solanum lycopersicum L. como plantas hospederas. Los resultados obtenidos en pimiento y tomate fueron respectivamente: supervivencia pupal: 86.86 ± 1.94 y 83,45 ± 2,13%; longevidad de la hembra: 18,19 ± 1,61 y 17,00 ± 0,92 días; proporción sexual: 0,34 ± 0,06 y 0,47 ± 0,05 hembras/(machos + hembras; l x50: 21 y 18 días; r m: 0,226 ± 0,061 y 0,228 ± 0,057 ninfas parasitadas/hembra/día; Ro: 189,71 ± 24,25 y 154,65 ± 17,58 ninfas parasitadas/hembra; T: 25,88 ± 0,42 y 24,03 ± 0,34 días. Los resultados obtenidos son una contribución al conocimiento de la población local del parasitoide y su posible papel como agente de control biológico de B. tabaci.The estimation of biological attributes of natural enemies prior to its use in the field is an important tool in a biological control program. The objective of the present paper was to evaluate the main biological parameters of Eretmocerus mundus Mercet, a parasitoid of Bemisia tabaci (Gennadius, under controlled laboratory conditions. Parasitoid survival, female longevity, fecundity, sex rate, intrinsic rate of natural increase (r m, net reproductive rate (Ro and generational time (T were studied using life tables, with pepper (Capsicum annuum L. and tomato (Solanum lycopersicum L. as host plants. Results

A review of aphid parasitoids and their associations in Algeria (Hymenoptera: Braconidae: Aphidiinae; Hemiptera: Aphidoidea)

Czech Academy of Sciences Publication Activity Database

Laamari, M.; Chaouche, S. T.; Halimi, C. W.; Benferhat, S.; Abbes, S. B.; Khenissa, N.; Starý, Petr

2012-01-01

Roč. 20, č. 1 (2012), s. 161-170 ISSN 1021-3589 Institutional research plan: CEZ:AV0Z50070508 Keywords : parasitoids * Diuraphis noxia * Lysiphlebus testaceipes Subject RIV: EH - Ecology, Behaviour Impact factor: 0.969, year: 2012 http://www.bioone.org/doi/pdf/10.4001/003.020.0120

Sex differences in metabolic rates in field crickets and their dipteran parasitoids.

Science.gov (United States)

Kolluru, G R; Chappell, M A; Zuk, M

2004-11-01

Sex differences in metabolic rate (MR) can result from dimorphism in the performance of energetically demanding activities. Male crickets (Teleogryllus oceanicus) engage in costly calling and aggressive activity not performed by females. Consistent with this difference, we found higher maximal MR, factorial scope, and fat content in males than females. T. oceanicus song is also costly because it attracts the parasitoid fly Ormia ochracea. Parasitized crickets had reduced maximal MR consistent with a metabolic cost to harboring larvae. This cost was greater for females, either because females invest more heavily into reproduction at the expense of metabolic capacity, or because males are under stronger selection to respond to infection. Little is known about O. ochracea outside of its auditory system and parasitic lifestyle. We observed greater resting MR in male flies, possibly reflecting a sex difference in the requirement for metabolic power output, because male flies perform potentially costly mating behavior not seen in females. We found a positive relationship between larval density within a cricket and pupal resting MR, suggesting that crickets in good condition are able to both harbor more larvae and produce larvae with higher resting MR. These results reveal a complex interplay between the metabolism of crickets and their fly parasitoids.

Urban land use decouples plant-herbivore-parasitoid interactions at multiple spatial scales.

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Amanda E Nelson

Full Text Available Intense urban and agricultural development alters habitats, increases fragmentation, and may decouple trophic interactions if plants or animals cannot disperse to needed resources. Specialist insects represent a substantial proportion of global biodiversity and their fidelity to discrete microhabitats provides a powerful framework for investigating organismal responses to human land use. We sampled site occupancy and densities for two plant-herbivore-parasitoid systems from 250 sites across a 360 km2 urban/agricultural landscape to ask whether and how human development decouples interactions between trophic levels. We compared patterns of site occupancy, host plant density, herbivory and parasitism rates of insects at two trophic levels with respect to landcover at multiple spatial scales. Geospatial analyses were used to identify landcover characters predictive of insect distributions. We found that herbivorous insect densities were decoupled from host tree densities in urban landcover types at several spatial scales. This effect was amplified for the third trophic level in one of the two insect systems: despite being abundant regionally, a parasitoid species was absent from all urban/suburban landcover even where its herbivore host was common. Our results indicate that human land use patterns limit distributions of specialist insects. Dispersal constraints associated with urban built development are specifically implicated as a limiting factor.

Tritrophic choice experiments with Bt plants, the diamondback moth (Plutella xylostella) and the parasitoid Cotesia plutellae

NARCIS (Netherlands)

Schuler, T.H.; Potting, R.P.J.; Denholm, I.; Clark, S.J.; Clark, A.J.; Stewart, C.N.; Poppy, G.M.

2003-01-01

Parasitoids are important natural enemies of many pest species and are used extensively in biological and integrated control programmes. Crop plants transformed to express toxin genes derived from Bacillus thuringiensis (Bt) provide high levels of resistance to certain pest species, which is likely

Convergent development of a parasitoid wasp on three host species with differing mass and growth potential

NARCIS (Netherlands)

Harvey, J.A.; Molina, A.C.; Bezemer, T.M.; Malcicka, M.

2015-01-01

Koinobiont parasitoids develop in hosts that continue feeding and growing during the course of parasitism. Here, we compared development of a solitary koinobiont endoparasitoid, Meteorus pulchricornis Westmael (Hymenoptera: Braconidae), in second (L2) and fourth (L4) instars of three host species

Trophic transfer of soil arsenate and associated toxic effects in a plant-aphid-parasitoid system

Science.gov (United States)

Lee, Y. S.; Wee, J.; Lee, M.; Hong, J.; Cho, K.

2017-12-01

Terrestrial toxic effects of soil arsenic were studied using a model system consisting of soil which artificially treated with arsenic, Capsicum annum,Myzus persicae and Aphidus colemani. We investigated the transfer of arsenic in a soil-plant-aphid system and toxic effect of elevated arsenic through a plant-aphid-parasitoid system. To remove the effect of poor plant growth on aphid performance, test concentrations which have a no effect on health plant growth were selected. Arsenic concentration of growth medium, plant tissues (root, stem, leaf) aphids were measured to observe the arsenic transfer. Correlation matrix was made with arsenic in growth medium which extracted with three extractants (aquaregia, 0.01 M CaCl2 and deionized water), arsenic in plant tissues and plant performance. Toxic effects of elevated arsenic concentrations on each species were investigated at population level. Studied plant performances were dry weight of each tissue, elongation of roots and stems, area of leaves, chlorophyll content of leaves, protein content of leaves and sugar content of leaves. Mean development time, fecundity and honeydew excretion of the aphids and host choice capacity and parasitism success of the parasitoids were examined. In addition, enzyme activities of the plants and the aphids against reactive oxygen species (ROS) induced by arsenic stress were also investigated. The results suggest that arsenic concentration in plant tissues and aphids were elevated with increased concentration of arsenic in soil. Decreased fecundity and honeydew excretion of aphids were observed and decreased eclosion rate of parasitoids were observed with increased arsenic treatment in growth medium. The results showed low concentration of arsenic in soil can transfer through food chain and can impact on higher trophic level species.

Mating Frequency and Effects on Sex Ratio in Female Parasitoids of xanthopimpla Stemmator (Thunberg). Implications in biological control Programmes

International Nuclear Information System (INIS)

Gitau, C.W.

2002-01-01

Cereals, especially maize and sorghum are the most important field crops in Africa. classical biological Control is a management strategy that employs natural enemies against exotic pests on cereal crops. The method has been used against Chilo partellus (Swinhoe) (Lepidoptera: Crambidae), an introduced pest of maize, using the larval parasitoid cotesia flavipes (Cameron). However, C. flavipes is not able to attack all stem borer species in targeted areas. to complement its work, Xanthopimpla stemmator has successfully been established in Mauritius on Chilo sacchariphagus (Bojer). It is a common phenomenon for haplo-diploid parasitoids to give rise to male progeny when insemination does not take place. Mating becomes important to the parasitoid population since a male biased sex ratio can bring about collapse of the population. The aim of this study was to determine wether xanthopimpla stemmator females mat more than once and wether sex ratio of progeny is affected by multiple mating in female X. stemmator. The female showed a tendency to mate once. Multiple mating did not have any significant effect on either sex ratio or longevity. More males were produced in multiple mated females than once mated females.The effect of multiple mating in X. stemmator on sex ratio in relation to biocontrol programmes are discussed

40 CFR 180.1101 - Parasitic (parasitoid) and predatory insects; exemption from the requirement of a tolerance.

Science.gov (United States)

2010-07-01

... insects; exemption from the requirement of a tolerance. 180.1101 Section 180.1101 Protection of... predatory insects; exemption from the requirement of a tolerance. Parasitic (parasitoid) and predatory insects are exempted from the requirement of a tolerance for residues when they are used in accordance...

Nectar exploitation by herbivores and their parasitoids is a function of flower species and relative humidity

NARCIS (Netherlands)

Winkler, K.; Wäckers, F.L.; Kaufman, L.V.; Larraz, V.; Lenteren, van J.C.

2009-01-01

In conservation biological control, diversification of the agro ecosystem with flowering vegetation is seen as an important tool to support the broad range of predators and parasitoids that require nectar and pollen sources to survive and reproduce. In order to identify flowering plants that provide

The sublethal effects of endosulfan on the circadian rhythms and locomotor activity of two sympatric parasitoid species.

Science.gov (United States)

Delpuech, Jean-Marie; Bussod, Sophie; Amar, Aurelien

2015-08-01

The organochlorine insecticide endosulfan is dispersed worldwide and significantly contributes to environmental pollution. It is an antagonist of the neurotransmitter gamma-aminobutyric acid (GABA), which is also indirectly involved in photoperiodic time measurement. In this study, we show that endosulfan at a dose as low as LC 0.1 modified the rhythm of locomotor activity of two sympatric parasitoid species, Leptopilina boulardi and Leptopilina heterotoma. The insecticide strongly increased the nocturnal activity of both species and synchronized their diurnal activity; these activities were not synchronized under control conditions. Parasitoids are important species in ecosystems because they control the populations of other insects. In this paper, we discuss the possible consequences of these sublethal effects and highlight the importance of such effects in evaluating the consequences of environmental pollution due to insecticides. Copyright © 2015 Elsevier Ltd. All rights reserved.

Body Odors of Parasitized Caterpillars Give Away the Presence of Parasitoid Larvae to Their Primary Hyperparasitoid Enemies

NARCIS (Netherlands)

Zhu, Feng; Weldegergis, Berhane T.; Lhie, Boris; Harvey, Jeffrey A.; Dicke, Marcel; Poelman, Erik H.

2014-01-01

Foraging success of parasitoids depends on the utilization of reliable information on the presence of their often, inconspicuous hosts. These parasitic wasps use herbivore-induced plant volatiles (HIPVs) that provide reliable cues on host presence. However, host searching of hyperparasitoids, a

Body odors of parasitized caterpillars give away the presence of parasitoid larvae to their primary hyperparasitoid enemies

NARCIS (Netherlands)

Zhu, F.; Weldegergis, B.T.; Lhie, B.; Harvey, J.A.; Dicke, M.; Poelman, E.H.

2014-01-01

Foraging success of parasitoids depends on the utilization of reliable information on the presence of their often, inconspicuous hosts. These parasitic wasps use herbivore-induced plant volatiles (HIPVs) that provide reliable cues on host presence. However, host searching of hyperparasitoids, a

Geographical distribution and genetic relatedness of sympatrical thelytokous and arrhenotokous populations of the parasitoid Venturia canescens (Hymenoptera)

NARCIS (Netherlands)

Schneider, M.V.; Beukeboom, L.W.; Driessen, G.; Lapchin, L.; Bernstein, C.; Alphen, J.J.M. van

2002-01-01

Theory predicts that asexual reproduction has a competitive advantage over sexual reproduction because of the twofold cost of producing males. Few systems are suitable for directly testing this prediction. In the solitary parasitoid wasp Venturia canescens both arrhenotokously (sexual) and

Understanding biological control of greenhouse whitefly with the parasitoid Encarsia formosa : from individual behaviour to population dynamics

NARCIS (Netherlands)

Roermund, van H.J.W.

1995-01-01

The greenhouse whitefly, Trialeurodes vaporariorum (Westwood) (Homoptera, Aleyrodidae), is a very common, highly polyphagous pest insect all over the world. Biological control of whiteflies with the parasitoid Encarsia formosa Gahan (Hymenoptera, Aphelinidae) was already applied in the 1920s in

Suitability of new and old association hosts for the development of selected microgastrine parasitoids of gramineous stemborers

NARCIS (Netherlands)

Ngi-Song, A.J.; Overholt, W.A.; Smith, J.W.; Vinson, S.B.

1999-01-01

The present study examined the acceptability and suitability of Old World stemborers (Chilo partellus and C. orichalcociliellus) for the development of New World parasitoids (Apanteles deplanatus and A. minator) and New World stemborers (Diatraea saccharalis and D. grandiosella) for the development

Comparative AFLP reveals paternal sex ratio chromosome specific DNA sequences in the parasitoid wasp Trichogramma kaykai

NARCIS (Netherlands)

Vugt, van J.J.F.A.; Hulst, van der R.G.M.; Pruijssers, A.; Verbaarschot, P.G.H.; Stouthamer, R.; Jong, de H.

2009-01-01

The parasitoid wasp Trichogramma kaykai with a haplo-diploid sex determination has a B chromosome called the paternal sex ratio (PSR) chromosome that confers paternal genome loss during early embryogenesis, resulting in male offspring. So far, it is not well known whether the PSR chromosome has

Biocontrol Potential of Lariophagus distinguendus (Hymenoptera: Pteromalidae) Against Sitophilus granarius (Coleoptera: Curculionidae) at Low Temperatures: Reproduction and Parasitoid-Induced Mortality

DEFF Research Database (Denmark)

Hansen, Lise Stengård

2007-01-01

Lariophagus distinguendus Förster (Hymenoptera: Pteromalidae) has been suggested as a biological control agent against the granary weevil, Sitophilus granarius (L.), in grain stores. Information on the effect of low temperatures prevailing in grain stores is necessary to be able to predict...... the potential of this parasitoid against S. granarius in temperate regions, where grain is cooled with ambient air to achieve safe storage conditions. The influence of constant temperatures of 16, 18, and 20°C on life table parameters and parasitoid-induced mortality (PIM) was investigated in the laboratory. L...... is quicker than that of its host, estimated from the literature; and it kills many hosts in addition to those used for reproduction....

The parasitoids of the African white rice borer, Maliarpha separatella Ragonot (Lepidoptera: Pyralidae)

OpenAIRE

Polaszek, A.; Fitton, M.G.; Bianchi, G.; Huddleston, T.

2017-01-01

A key is provided for the recognition of the hymenopterous parasitoids of the African white rice borer, Maliarpha separatella Ragonot, a pest of rice in Africa and Madagascar. Five species are described as new: Braconidae: Chelonus maudae Huddleston, Rhacanotus carinafus Polaszek; Ichneumonidae: Prisfomerus bullis Fitton, Prisfomerus caris Fitton, Venturia jordanae Fitton. The following synonyms are proposed: Goniozus indicus Muesebeck, G. natalensis Gordh and G. procerae Risbec are synonymiz...

Ecosystem-Based Incorporation of Nectar-Producing Plants for Stink Bug Parasitoids

Directory of Open Access Journals (Sweden)

Glynn Tillman

2017-06-01

Full Text Available Adult parasitoids of pest insects rely on floral resources for survival and reproduction, but can be food-deprived in intensively managed agricultural systems lacking these resources. Stink bugs are serious pests for crops in southwest Georgia. Provisioning nectar-producing plants for parasitoids of stink bugs potentially can enhance biocontrol of these pests. Knowledge of spatial and temporal availability and distribution of stink bugs in host plants is necessary for appropriate timing and placement of flowering plants in agroecosystems. Stink bugs move between closely associated host plants throughout the growing season in response to deteriorating suitability of their host plants. In peanut-cotton farmscapes, stink bugs develop in peanut, and subsequently the adults disperse into adjacent cotton. Parasitism of Nezara viridula (L. adults by Trichopoda pennipes (F. at the peanut-cotton interface was significantly higher in cotton with a strip of milkweed or buckwheat between the two crops than in cotton alone. Milkweed and buckwheat also provided nectar to a wide range of insect pollinators. Monarch butterflies fed on milkweed. When placed between peanut and cotton, a strip of soybean was an effective trap crop for cotton, reducing economic damage. Incorporation of buckwheat near soybean enhanced parasitism of Euschistus servus (Say eggs by Telenomus podisi Ashmead in cotton. In conclusion, nectar provision enhances biocontrol of stink bugs, acts together with other management tactics for stink bug control, and aids in conservation of natural enemies, insect pollinators, and the monarch butterfly.

Rapid establishment of a regular distribution of adult tropical Drosophila parasitoids in a multi-patch environment by patch defence behaviour.

Science.gov (United States)

de Jong, Peter W; Hemerik, Lia; Gort, Gerrit; van Alphen, Jacques J M

2011-01-01

Females of the larval parasitoid of Drosophila, Asobara citri, from sub-Saharan Africa, defend patches with hosts by fighting and chasing conspecific females upon encounter. Females of the closely related, palearctic species Asobara tabida do not defend patches and often search simultaneously in the same patch. The effect of patch defence by A. citri females on their distribution in a multi-patch environment was investigated, and their distributions were compared with those of A. tabida. For both species 20 females were released from two release-points in replicate experiments. Females of A. citri quickly reached a regular distribution across 16 patches, with a small variance/mean ratio per patch. Conversely, A. tabida females initially showed a clumped distribution, and after gradual dispersion, a more Poisson-like distribution across patches resulted (variance/mean ratio was closer to 1 and higher than for A. citri). The dispersion of A. tabida was most probably an effect of exploitation: these parasitoids increasingly made shorter visits to already exploited patches. We briefly discuss hypotheses on the adaptive significance of patch defence behaviour or its absence in the light of differences in the natural history of both parasitoid species, notably the spatial distribution of their hosts.

Heat stress affects male reproduction in a parasitoid wasp.

Science.gov (United States)

Nguyen, Thanh Manh; Bressac, Christophe; Chevrier, Claude

2013-03-01

In insects, reproductive success and survival are affected by temperature. Reproduction is more sensitive than other physiological traits. While the effects of heat stress on females are well known, the effects on males are less clear. Hymenopteran parasitoids are valuable for studying the consequences of heat stress on male reproduction. In these species, through arrhenotoquous parthenogenesis, the sex ratio of the offspring is directly dependent on the sperm stock acquired by females during copulation. In the lab, heat temperature treatments (32-44°C) were applied for 3 days in the pupal stage of Anisopteromalus calandrae males, and development was completed at 30°C. Three different effects were observed depending on the temperature: mortality above 42°C, sterility of emerging males at 40°C, and sub-fertility at 38°C. This sub-fertility is characterized by a dramatic decrease in male sperm supplies, of up to 7% compared to control males. In the course of ageing, the sperm stock of sub-fertile males increases but never reaches the level of control males. Survival was significantly higher in control (30°C) males than those treated at 38°C. Male mating ability was similar whatever the treatment (control and 38°C), but females mated with 38°C-treated males stored 100 times less sperm on average than those mated with control males. The offspring sex ratio of females mated with 38°C-treated males was strongly male biased. The physiological mechanisms are as yet unknown. The relationship between temperature, sperm stock and sex ratio should be taken into account in the management of parasitoids for integrated pest management. Copyright © 2012 Elsevier Ltd. All rights reserved.

Asymmetric total synthesis of a putative sex pheromone component from the parasitoid wasp Trichogramma turkestanica

NARCIS (Netherlands)

Geerdink, Danny; Buter, Jeffrey; van Beek, Teris A.; Minnaard, Adriaan J.

2014-01-01

Virgin females of the parasitoid wasp Trichogramma turkestanica produce minute amounts of a sex pheromone, the identity of which has not been fully established. The enantioselective synthesis of a putative component of this pheromone, (6S,8S,10S)-4,6,8,10-tetramethyltrideca-2E,4E-dien-1-ol (2), is

Influence of adult nutrition on the relationship between body size and reproductive parameters in a parasitoid wasp

NARCIS (Netherlands)

Bezemer, T.M.; Harvey, J.A.; Mills, N.J.

2005-01-01

1. An important constraint upon life-history evolution in parasitoids is the limit imposed by body size on allocation of limited metabolic resources to different fitness-related physiological functions such as reproduction and survival. 2. The influence of adult nutrition on reproductive and

Reproductive and developmental biology of the emerald ash borer parasitoid Spathius galinae (Hymenoptera: Braconidae) as affected by temperature

Science.gov (United States)

Emerald ash borer Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) is an invasive pest of serious concern in North America. To complement ongoing biological control efforts, Spathius galinae Belokobylskij and Strazenac (Hymenoptera: Braconidae), a recently-described specialist parasitoid of ...

Life inside a gall: closeness does not favour horizontal transmission of Rickettsia between a gall wasp and its parasitoid.

Science.gov (United States)

Gualtieri, Liberata; Nugnes, Francesco; Nappo, Anna G; Gebiola, Marco; Bernardo, Umberto

2017-07-01

The incidence of horizontal transmission as a route for spreading symbiont infections is still being debated, but a common view is that horizontal transfers require intimate between-species relationships. Here we study a system that meets ideal requirements for horizontal transmission: the gall wasp Leptocybe invasa and its parasitoid Quadrastichus mendeli (Hymenoptera: Eulophidae). These wasps belong to the same subfamily, spend most of their lives inside the same minute gall and are both infected by Rickettsia, a maternally inherited endosymbiotic bacteria that infects several arthropods, sometimes manipulating their reproduction, like inducing thelytokous parthenogenesis in L. invasa. Despite intimate contact, close phylogenetic relationship and the parasitoid's host specificity, we show that host and parasitoid do not share the same Rickettsia. We provide indirect evidence that Rickettsia infecting Q. mendeli may be inducing thelytokous parthenogenesis, as the symbiont is densely present in the reproductive apparatus and is vertically transmitted. Phylogenetic analyses based on 16S and gltA placed this symbiont in the leech group. The confirmed and presumed parthenogenesis-inducing Rickettsia discovered so far only infect eulophid wasps, and belong to three different groups, suggesting multiple independent evolution of the parthenogenesis inducing phenotype. We also show some degree of cospeciation between Rickettsia and their eulophid hosts. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Parasitoid Diaeretiella rapae (Hymenoptera: Braconidae) Adjusts Reproductive Strategy When Competing for Hosts.

Science.gov (United States)

Kant, Rashmi; Minor, Maria A

2017-06-01

Parasitoid fitness depends on its ability to manipulate reproductive strategies when in competition. This study investigated the parasitism and sex allocation strategies of the parasitic wasp Diaeretiella rapae McIntosh at a range of host (Brevicoryne brassicae L.) and conspecific densities. The results suggest that D. rapae females adjust their progeny production and progeny sex ratio with changing competition. When foraging alone, female D. rapae parasitize larger number of B. brassicae nymphs when the number of available hosts is increased, but the overall proportion of parasitized hosts decreases with increase in host density. The proportion of female offspring also decreases with elevated host density. Increase in the number of female D. rapae foraging together increased total parasitism, but reduced relative contribution of each individual female. The number of female progeny decreased when multiple females competed for the same host. However, foraging experience in the presence of one or more conspecifics increased the parasitism rate and proportion of female progeny. Competing females were more active during oviposition and had shorter lives. The study suggests that both host and foundress (female parasitoid) densities have significant effect on progeny production, sex allocation, and longevity of foraging females. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Diversidad de avispas parasitoides en un sistema silvopastoril orgánico de producción ganadera de Colombia

Directory of Open Access Journals (Sweden)

L. López

2013-01-01

Full Text Available En el sistema silvopastoril de la Reserva Natural El Hatico (Rneh en El Cerrito, Valle (Colombia, las legumbres del algarrobo (Prosopis juliflora, se utilizan como alimento para bovinos. Sin embargo, desde 2006, la polilla Eccopsis galapagana (Lepidoptera: Tortricidae, afecta el follaje y la producción de legumbres. Motivados por el brote poblacional de esta polilla, se propuso identificar las especies de parasitoides, su distribución, su densidad y relacionarlas con el hábitat y el daño del insecto sobre P. juliflora. Se capturaron himenópteros, utilizando platos amarillos ubicados en 24 árboles de algarrobo escogidos al azar, en cuatro lotes dentro del sistema silvopastoril y al interior del bosque adyacente (control. Se midió el porcentaje de herbivoría, por E. galapagana; la cobertura del dosel de cada árbol muestreado, la temperatura y se determinó la composición vegetal de cada lote. De un total de 1,376 parasitoides -pertenecientes a siete superfamilias, 18 familias y 42 morfoespecies- el 71% se identificó hasta género. La superfamilia más representativa fue Chalcidoidea, y Encyrtidae la familia más abundante. Se encontró una relación positiva entre composición, cobertura vegetal y abundancia de parasitoides; pero esto no se tradujo en una disminución de los porcentajes de herbivoría por la polilla.

Fruit flies (Diptera, Tephritidae and their parasitoids on cultivated and wild hosts in the Cerrado-Pantanal ecotone in Mato Grosso do Sul, Brazil

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Tiago Ledesma Taira

2013-09-01

Full Text Available Fruit flies (Diptera, Tephritidae and their parasitoids on cultivated and wild hosts in the Cerrado-Pantanal ecotone in Mato Grosso do Sul, Brazil. Information on frugivorous flies in cultivated or wild host plants and their parasitoids in the Cerrado-Pantanal ecotone in Aquidauana, Mato Grosso do Sul is presented and discussed. Fruit fly samples were collected weekly in specific fruit trees, and McPhail® traps were installed in the same trees for a period of two years. The fruit flies infested ripe and unripe fruits of Averrhoa carambola L., Schoepfia sp., Psidium guajava L. and Pouteria torta (Mart. Radlk and mature fruits of Anacardium occidentale L. and Inga laurina (Sw. Willd. Nineteen fruit fly species were obtained with the combination of sampling methods (collecting fruits and trapping, nine of them obtained with both methods, five found only in fruits and five only in traps. This is the first record of Anastrepha striata Schiner in a species of Sapotaceae, as well as for A. castanea Norrbom and A. daciformes Bezzi in Schoepfia sp. (Olacaceae, and for A. distincta Greene in fruits of P. guajava in the state of Mato Grosso do Sul. Fruit collections simultaneously associated with capture of fruit flies by McPhail traps in the same host plants are essential to understand the diversity of fruit flies and their relationship with hosts and parasitoids. Species of Braconidae and Pteromalidae were recovered, where Doryctobracon areolatus (Szépligeti was the most abundant parasitoid in larvae of tephritids infesting both cultivated and wild host fruits.

Bottom-up effects on a plant-endophage-parasitoid system: The role of flower-head size and chemistry.

NARCIS (Netherlands)

Tavares Correa Dias, A.; Roberto Trigo, J.; Lewinsohn, Th.M.

2010-01-01

The effects of water and nutrient addition on a trophic chain were studied in a plant-endophage-parasitoid system comprised of insects associated with flower heads of Chromolaena squalida (Asteraceae). Nine species of endophages associated with C. squalida flower heads were found, belonging to two

Use of acoustic vortices in acoustic levitation

DEFF Research Database (Denmark)

Cutanda Henriquez, Vicente; Santillan, Arturo Orozco; Juhl, Peter Møller

2009-01-01

Acoustic fields are known to exert forces on the surfaces of objects. These forces are noticeable if the sound pressure is sufficiently high. Two phenomena where acoustic forces are relevant are: i) acoustic levitation, where strong standing waves can hold small objects at certain positions......, counterbalancing their weight, and ii) acoustic vortices, spinning sound fields that can impinge angular momentum and cause rotation of objects. In this contribution, both force-creating sound fields are studied by means of numerical simulations. The Boundary Element Method is employed to this end. The simulation...... of acoustical vortices uses an efficient numerical implementation based on the superposition of two orthogonal sound fields with a delay of 90° between them. It is shown that acoustic levitation and the use of acoustic vortices can be combined to manipulate objects in an efficient and controlled manner without...

Anastrepha species (Diptera: Tephritidae, their host plants and parasitoids (Hymenoptera in the state of Roraima, Brazil: state of the art

Directory of Open Access Journals (Sweden)

Alberto Luiz Marsaro Júnior

2017-02-01

Full Text Available http://dx.doi.org/10.5007/2175-7925.2017v30n1p13 The aim of this review was to update the available information on Anastrepha species in the state of Roraima, Brazil, with emphasis on distribution, host plants and parasitoids. In total, 25 species of Anastrepha and 27 host plant species have been recorded to date in Roraima. Anastrepha striata and A. obliqua are widely distributed in the state. Anastrepha obliqua is the most polyphagous species, where it is associated with 13 hosts. Six species of parasitoids of Anastrepha have been reported in Roraima. Of these, Doryctobracon areolatus is the most abundant and has been associated with the largest number of Anastrepha species.

Acoustic emission

International Nuclear Information System (INIS)

Nichols, R.W.

1976-01-01

The volume contains six papers which together provide an overall review of the inspection technique known as acoustic emission or stress wave emission. The titles are: a welder's introduction to acoustic emission technology; use of acoustic emission for detection of defects as they arise during fabrication; examples of laboratory application and assessment of acoustic emission in the United Kingdom; (Part I: acoustic emission behaviour of low alloy steels; Part II: fatigue crack assessment from proof testing and continuous monitoring); inspection of selected areas of engineering structures by acoustic emission; Japanese experience in laboratory and practical applications of acoustic emission to welded structures; and ASME acoustic emission code status. (U.K.)

Nectar-providing plants enhance the energetic state of herbivores as well as their parasitoids under field conditions

NARCIS (Netherlands)

Winkler, K.; Wackers, F.; Pinto, D.M.

2009-01-01

1. The use of flowering vegetation has been widely advocated as a strategy for providing parasitoids and predators with nectar and pollen. However, their herbivorous hosts and prey may exploit floral food sources as well. 2. Previous laboratory studies have shown that not all flower species are

Differing success of defense strategies in two parasitoid wasps in protecting their pupae against a secondary hyperparasitoid

NARCIS (Netherlands)

Harvey, J.A.; Gols, R.; Tanaka, T.

2011-01-01

During their larval development, endoparasitoids are known to dispose of host resources in several different ways. Some parasitoid wasps consume most or all tissues of the host, whereas others consume a small fraction of host resources and either ensure that the host moves away from the pupation

Differing Success of Defense Strategies in Two Parasitoid Wasps in Protecting Their Pupae Against a Secondary Hyperparasitoid

NARCIS (Netherlands)

Harvey, J.A.; Gols, R.; Tanaka, T.

2011-01-01

During their larval development, endoparasitoids are known to dispose of host resources in several different ways. Some parasitoid wasps consume most or all tissues of the host, whereas others consume a small fraction of host resources and either ensure that the host moves away from the pupation

Vitex agnus castus and Euphorbia characias ssp. wulfenii as reservoirs of aphid parasitoids (Hymenoptera: Braconidae: Aphidiinae)

Czech Academy of Sciences Publication Activity Database

Kavallieratos, N. G.; Tomanovic, Ž.; Starý, Petr; Emmanouel, N. E.

2008-01-01

Roč. 91, č. 2 (2008), s. 179-191 ISSN 0015-4040 Grant - others:The Ministry of Science nad Environment Protection of the Republic of Serbia(CS) 143006B Institutional research plan: CEZ:AV0Z50070508 Keywords : aphids * parasitoids * reservoirs Subject RIV: EH - Ecology, Behaviour Impact factor: 0.886, year: 2008

Sexual dimorphism in the parasitoid wasps Aphidius balcanicus, Aphidius rosae, and Aphidius urticae (Hymenoptera: Braconidae: Aphidiinae)

Czech Academy of Sciences Publication Activity Database

Petrović, A.; Tomanović, Ž.; Kavallieratos, N. G.; Mitrovski Bogdanović, A.; Starý, Petr; Ivanović, A.

2014-01-01

Roč. 107, č. 5 (2014), s. 1027-1032 ISSN 0013-8746 Grant - others:The Ministry of Education, Science and Technological Development of the Republic of Serbia(RS) 43001 Institutional support: RVO:60077344 Keywords : geometric morphometric * parasitoid wasp * sexual size dimorphism Subject RIV: EA - Cell Biology Impact factor: 1.190, year: 2014

Life-history parameters of Encarsia formosa, Eretmocerus eremicus and E. Mundus, aphelinid parasitoids of Bemisia argentifolii (Hemiptera: Aleyrodidae)

NARCIS (Netherlands)

Qiu, Y.T.; Lenteren, van J.C.; Drost, Y.C.; Posthuma-Doodeman, J.A.M.

2004-01-01

Life-history parameters (juvenile development time, adult longevity, host instar preference and rate of parasitism) offour parasitoids of Bemisia argentifolii (two strains of Encarsia formosa (D and B), Eretmocerus eremicus and Eretmocerus mundus) Were Studied in the laboratory. At 15degreesC

Translational illusion of acoustic sources by transformation acoustics.

Science.gov (United States)

Sun, Fei; Li, Shichao; He, Sailing

2017-09-01

An acoustic illusion of creating a translated acoustic source is designed by utilizing transformation acoustics. An acoustic source shifter (ASS) composed of layered acoustic metamaterials is designed to achieve such an illusion. A practical example where the ASS is made with naturally available materials is also given. Numerical simulations verify the performance of the proposed device. The designed ASS may have some applications in, e.g., anti-sonar detection.

Chemical investigations of volatile kairomones produced by Hyphantria cunea (Drury), a host of the parasitoid Chouioia cunea Yang.

Science.gov (United States)

Zhu, G; Pan, L; Zhao, Y; Zhang, X; Wang, F; Yu, Y; Fan, W; Liu, Q; Zhang, S; Li, M

2017-04-01

In tritrophic 'plants-herbivores-natural enemies' systems, there are relatively few reports concerning the role(s) of kairomones in pupal parasitism. Chouioia cunea Yang (Hymenoptera: Eulophidae), an endoparasitic chalcid wasp, parasitizes pupae of the fall webworm (Hyphantria cunea Drury). The role of host-related kairomones was investigated using electroantennogram (EAG) and behavioral techniques. Chemicals from some host stages (pupae) and host by-products (frass), induced arrestment behavior of female parasitoids, while chemicals from prepupae, were inactive. Gas chromatography-mass spectrometry analysis of volatiles collected from pupae, frass and prepupae using solid-phase microextration revealed seven compounds with carbon chain lengths ranging from C4 to C20. All of the chemicals elicited significant EAG responses in C. cunea. Y-tube olfactometer bioassays demonstrated a significant positive response of mated female C. cunea to 1-dodecene. These data provide a better understanding of the host location mechanisms of pupal parasitoid.

FRUIT FLIES (DIPTERA: TEPHRITIDAE AND THEIR PARASITOIDS ASSOCIATED WITH DIFFERENT HOG PLUM GENOTYPES IN TERESINA, PIAUÍ

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LEONARDO DA SILVA SOUSA

2017-10-01

Full Text Available ABSTRACT The aim of this work was to identify and quantify the infestation of fruit fly species and their parasitoids, associated with 20 hog plum genotypes (Spondias mombin L. in a commercial orchard in Teresina, Piauí, Brazil. The survey was conducted by fruit sampling and monitoring through traps stocked with bait food, in the period from January to December 2012. Overall, 6560 fruits were collected (79.58 kg, resulting in 23059 pupae, of which 10080 fruit flies of the genus Anastrepha and 4984 braconid parasitoids emerged. Anastrepha obliqua species was the predominant with 99.92%. F16P13 and F11P10 genotypes had the highest infestation indexes and F15P11 and F04P01 genotypes, the lowest. The main parasitoids collected were Opius bellus (77.65%, Doryctobracon areolatus (19.88% and Utetes anastrephae (2.47%. The average parasitism rate among genotypes was of 30.46%. In traps, a total of 1434 fruit flies were collected, whose species were: A. obliqua (97.6%, A. serpentina (1.4%, A. fraterculus (0.4%, A. striata (0.4%, A. dissimilis (0.1%, A. pseudoparallela (0.1%. Anastrepha obliqua species was predominant in the area, based on faunistic analysis. The infestation index in the orchard was relevant for five months (January-May, coinciding with the period of availability of hog plum fruits, reaching the highest peak in March (2.86 FAT. There was a significant negative correlation between number of fruit flies in the orchard and the average air temperature, and a significant positive correlation with rainfall and relative humidity. However, the main factor that influenced the observed infestation index in the hog plum orchard was fruit availability.

Biology and Behavior of Spathius agrili, a Parasitoid of the Emerald Ash Borer, Agrilus planipennis, in China

Science.gov (United States)

Yang, Zhong-Qi; Wang, Xiao-Yi; Gould, Juli R.; Reardon, Richard C.; Zhang, Yi-Nan; Liu, Gui-Jun; Liu, En-Shan

2010-01-01

Spathius agrili Yang (Hymenoptera: Braconidae) is a gregarious larval ectoparasitoid of the emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) and is a recently described species. Both pest and parasitoid are native to China. In Tianjin City, China, S. agrili typically exhibited 3–4 generations per year, overwintering as a prepupa in a cocoon inside the host gallery. The multiple generations of S. agrili overlapped with its host, as did the emergence dates of the overwintering generation. From a single host, 1–18 S. agrili successfully developed to the adult stage (average 8.4), but in all cases the host was killed. The sex ratio (female: male) of the parasitoid adults emerging from field-collected cocoons was 2:1, whereas the sex ratio of parasitoids reared from field collected eggs and larvae was greater than 3:1. On average, adult females lived 29.1 d, and males lived 23.6 d when fed with 20% honey solution, significantly longer than without a nutritional supplement. Sexual reproduction is the normal mode of reproduction, but in the laboratory females did reproduce parthenogenetically, producing only males. The average fecundity was 23.3 eggs per female in the laboratory. S. agrili developed through five larval instars, and the larvae fed gregariously on the host hemolymph. The generation time from egg to adult wasp was 27–28 d at 22–26°C. Natural parasitism rates were as high as 60%, and in October they reached over 90% in some stands. This study showed that S. agrili is a promising agent for biocontrol of A. planipennis. PMID:20569125

Temperature-dependent functional response of Spalangia cameroni (Perkins) (Hymenoptera: Pteromalidae), a parasitoid of Stomoxys calcitrans (L.) (Diptera: Muscidae)

DEFF Research Database (Denmark)

Skovgård, Henrik; Nachman, Gösta

2015-01-01

The effects of host density, temperature, and burial depths on the functional response of the synovigenic parasitoid Spalangia cameroni (Perkins) attacking pupae of the stable fly Stomoxys calcitrans (L.) were examined. Five temperatures (15, 20, 25, 30, and 35 degrees C), six host densities (2, ...

Effect of Maruca vitrata (Lepidoptera: Crambidae) host plants on life-history parameters of the parasitoid Apanteles taragamae (Hymenoptera: Braconidae)

NARCIS (Netherlands)

Dannon, A.E.; Tamo, M.; Agboton, C.; Huis, van A.; Dicke, M.

2012-01-01

The effect of four host plant species of the herbivore Maruca vitrata Fabricius (Lepidoptera: Crambidae) on development time, longevity, fecundity and sex ratio of the parasitoid Apanteles taragamae Viereck (Hymenoptera: Braconidae) was investigated under laboratory conditions. The larvae were

Nuevos registros de especies del género Eretmocerus (Hymenoptera: Aphelinidae, parasitoides de Trialeurodes vaporariorum y el complejo Bemisia tabaci (Hemiptera: Aleyrodidae en Argentina New records of species of the genus Eretmocerus (Hymenoptera: Aphelinidae, parasitoids of Trialeurodes vaporariorum and Bemisia tabaci complex (Hemiptera: Aleyrodidae in Argentina

Directory of Open Access Journals (Sweden)

Silvia N. López

2008-06-01

Full Text Available El objetivo de este trabajo es dar a conocer nuevos registros y distribuciones de las especies del género Eretmocerus Haldeman, parasitoides de las dos especies de mosca blanca que tienen mayor importancia económica en cultivos hortícolas y ornamentales en Argentina. Una especie de Eretmocerus Haldeman fue hallada parasitando a Trialeurodes vaporariorum (Westwood en Santa Fe y Buenos Aires; por sus caracteres morfológicos, se encuentra en el grupo californicus, cercana a corni Haldeman, podría tratarse de una nueva especie. Asimismo, se amplía la distribución geográfica de Eretmocerus mundus Mercet, enemigo natural del complejo Bemisia tabaci (Gennadius, a las provincias de San Juan y Buenos Aires.The objective of this paper is to report new records of species of the genus Eretmocerus Haldeman, parasitoids of the most important whitefly pest species in vegetables and ornamental crops in Argentina. One species was found parasitizing Trialeurodes vaporariorum (Westwood in Santa Fe and Buenos Aires provinces and it is grouped into californicus group near corni Haldeman, due to its morphological characters. It could be a new species. The known distribution of Eretmocerus mundus Mercet, a parasitoid of Bemisia tabaci (Gennadius, is enlarged to include the provinces of San Juan and Buenos Aires of Argentina.

Parasitoidism Rate and Life Table Parameters of Aphytis diaspidis (Howard (Hymenoptera: Aphelinidae and Hemiberlesia lataniae (Signoret (Hemiptera: Diaspididae Tasa de Parasitoidismo y Parámetros de Tabla de Vida de Aphytis diaspidis (Howard (Hymenoptera: Aphelinidae y Hemiberlesia lataniae (Signoret (Hemiptera: Diaspididae

Directory of Open Access Journals (Sweden)

Dennis Navea O

2012-09-01

Full Text Available Latania scale, Hemiberlesia lataniae (Signoret, has become a major pest of avocado (Persea americana Mill. in Chile and has reached high populations in the fruit because of limited natural control. The objective of this study was to identify the biological parameters of the parasitoid Aphytis diaspidis (Howard as a control agent of latania scale. Postembryonic development, parasitoidism rate, and life table parameters of the parasitoid and scale were determined under laboratory conditions. Aphytis diaspidis postembryonic development and parasitoidism rate varied significantly when evaluated on distinct latania scale stages with the highest survival (56% occurring at the third scale stage, it also had the shortest development time between egg and adult (19.14 d and the highest parasitoidism rate (66%. The intrinsic growth rate (r m was higher for A. diaspidis (r m = 0.099 than latania scale (r m = 0.068. These laboratory results demonstrated that A. diaspidis is an effective parasitoid for decreasing H. lataniae populations, especially in the third stage.La escama latania, Hemiberlesia lataniae (Signoret, se ha transformado en Chile en una plaga de importancia primaria en palto (Persea americana Mill., donde alcanza altas poblaciones en la fruta debido al escaso control natural existente. El objetivo del presente estudio fue conocer parámetros biológicos del parasitoide Aphytis diaspidis (Howard, como agente de control de la escama latania. Es asi como se determinó en laboratorio el desarrollo postembrionario, tasa de parasitoidismo, y parámetros de tabla de vida del parasitoide y la escama. El desarrollo postembrionario y la tasa de parasitoidismo de A. diaspidis varió significativamente al ser evaluado sobre distintos estadios de la escama latania, alcanzando el mayor porcentaje de supervivencia (56% sobre el tercer estadio de la escama, asi como el menor tiempo de desarrollo entre huevo y adulto (19,14 d y la máxima tasa de

Effects of molasses grass, Melinis minutiflora volatiles on the foraging behavior of the cereal stemborer parasitoid, Cotesia sesamiae

NARCIS (Netherlands)

Gohole, L.S.; Overholt, W.A.; Khan, Z.R.; Pickett, J.A.; Vet, L.E.M.

2003-01-01

Olfactory responses of the cereal stemborer parasitoid Cotesia sesamiae to volatiles emitted by gramineous host and nonhost plants of the stemborers were studied in a Y-tube olfactometer. The host plants were maize (Zea mays) and sorghum (Sorghum bicolor), while the nonhost plant was molasses grass

Effects of molasses grass, Melinis minutiflora volatiles on the foraging behavior of the cereal stemborer parasitoid, Cotesia sesamiae

NARCIS (Netherlands)

Gohole, L.S.; Overholt, W.A.; Khan, Z.U.; Pickett, J.A.; Vet, L.E.M.

2003-01-01

Olfactory responses of the cereal stemborer parasitoid Cotesia sesamiae to volatiles emitted by gramineous host and nonhost plants of the stemborers were studied in a Y-tube olfactometer. The host plants were maize (Zea mays) and sorghum ( Sorghum bicolor), while the nonhost plant was molasses grass

Fundamentals of Acoustics. Psychoacoustics and Hearing. Acoustical Measurements

Science.gov (United States)

Begault, Durand R.; Ahumada, Al (Technical Monitor)

1997-01-01

These are 3 chapters that will appear in a book titled "Building Acoustical Design", edited by Charles Salter. They are designed to introduce the reader to fundamental concepts of acoustics, particularly as they relate to the built environment. "Fundamentals of Acoustics" reviews basic concepts of sound waveform frequency, pressure, and phase. "Psychoacoustics and Hearing" discusses the human interpretation sound pressure as loudness, particularly as a function of frequency. "Acoustic Measurements" gives a simple overview of the time and frequency weightings for sound pressure measurements that are used in acoustical work.

Communication Acoustics

DEFF Research Database (Denmark)

Blauert, Jens

Communication Acoustics deals with the fundamentals of those areas of acoustics which are related to modern communication technologies. Due to the advent of digital signal processing and recording in acoustics, these areas have enjoyed an enormous upswing during the last 4 decades. The book...... the book a source of valuable information for those who want to improve or refresh their knowledge in the field of communication acoustics - and to work their way deeper into it. Due to its interdisciplinary character Communication Acoustics is bound to attract readers from many different areas, such as......: acoustics, cognitive science, speech science, and communication technology....

Abridged life tables for Cephalonomia stephanoderis and Prorops nasuta (Hymenoptera: Bethylidae) Parasitoids of Hypothenemus hampei (Coleoptera: Scolytidae) reared on artificial diet

Science.gov (United States)

Biological aspects and demographic parameters of Cephalonomia stephanoderis Betrem (Hymenoptera: Bethylidae) and Prorops nasuta Waterston (Hymenoptera: Bethylidae) parasitoids of the coffee berry borer (CBB), Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae: Scolytinae) were investigated usi...

Side effects of different pesticides used in citrus on the adult stage of the parasitoid Aphytis melinus DeBach (Hymenoptera Aphelinidae and its progeny

Directory of Open Access Journals (Sweden)

J. E. Gonzalez-Zamora

2013-05-01

Full Text Available Twelve pesticides commonly used in citrus in Spain were tested on adults of Aphytis melinus DeBach to determine their effects on parasitoid survival and fecundity, and the duration of the residue of each pesticide. Six of these pesticides were found to be harmless to moderately harmful to this parasitoid in a laboratory assay in closed Petri dishes: spinosad (bait formulation, azadirachtin, fenbutatin, fosetyl-Al, copper oxichloride, and mancozeb, with their scores on the reduction of beneficial capacity (RBC index being between 21.4 and 94.6% after one week. The other six pesticides classified as harmful were tested on citrus plants to study their persistence over time under greenhouse conditions: Pirimicarb, pyriproxifen, paraffinic oil, abamectin, chlorpyrifos, and lambda-cyhalothrin. Most of these products reduced their negative effect on adults of A. melinus between one and six weeks after treatment, although lambda-cyhalothrin was still harmful to parasitoids 11 weeks after application. This information can help growers and consultants to make decisions about pesticide selection and application timing in citrus in order to support IPM implementation when A. melinus is present.

Susceptibility of two hymenopteran parasitoids of Agrilus planipennis (Coleoptera: Buprestidae) to the entomopathogenic fungus Beauveria bassiana (Ascomycota: Hypocreales)

Science.gov (United States)

Kimberly M Dean; John D. Vandenberg; Michael H. Griggs; Leah S. Bauer; Melissa K. Fierke

2012-01-01

Emerald ash borer (EAB), Agrilus planipennis Fairmaire, native to Asia, is killing ash trees (Fraxinus spp.) across 15 states and southeastern Canada. Integrated pest management using biological control is the only viable long-term approach for controlling the spread of EAB outside of host resistance. Three hymenopteran parasitoids...

Acoustic source for generating an acoustic beam

Science.gov (United States)

Vu, Cung Khac; Sinha, Dipen N.; Pantea, Cristian

2016-05-31

An acoustic source for generating an acoustic beam includes a housing; a plurality of spaced apart piezo-electric layers disposed within the housing; and a non-linear medium filling between the plurality of layers. Each of the plurality of piezoelectric layers is configured to generate an acoustic wave. The non-linear medium and the plurality of piezo-electric material layers have a matching impedance so as to enhance a transmission of the acoustic wave generated by each of plurality of layers through the remaining plurality of layers.

Moscas frugívoras e seus parasitoides nos municípios de Pelotas e Capão do Leão, Rio Grande do Sul, Brasil Frugivorous flies and their parasitoids in the cities of Pelotas and Capão do Leão, Rio Grande do Sul, Brazil

Directory of Open Access Journals (Sweden)

Adrise Medeiros Nunes

2012-01-01

Full Text Available As moscas frugívoras (Tephritoidea são as principais pragas da fruticultura de clima temperado no Brasil. O objetivo do presente trabalho foi avaliar a infestação desses dípteros e a ocorrência de seus parasitoides em frutíferas nos municípios de Pelotas e Capão do Leão, localizados na região Sul, nas safras agrícolas de 2007/08 e 2008/09. Foram coletados frutos de araçazeiro-amarelo e vermelho (Psidium cattleianum Sabine, 1821, butiazeiro [Butia capitata (Mart. Becc., 1916], caquizeiro (Diospyros kaki Linnaeus, 1753, cerejeira-do-mato (Eugenia involucrata DC., 1828, goiabeira [Psidium guajava (Linnaeus, 1753], goiabeira-serrana [Acca sellowiana (Berg. Burret, 1941], nespereira [Eriobotrya japonica (Thunb. Lindley, 1822], pessegueiro [Prunus persicae (L. Batsch, 1801], pitangueira (Eugenia uniflora Linnaeus,1753 e uvalheira (Eugenia pyriformis Cambessèdes, 1832. Os frutos foram coletados e transportados para o laboratório, onde foram individualizados e determinados os seguintes parâmetros: índice de infestação das moscas, índice de parasitismo e frequência de indivíduos por espécie de parasitoide. Foram constatadas duas espécies de Tephritidae, Anastrepha fraterculus (Wiedemann, 1830 (90,5% e Ceratitis capitata (Wiedemann, 1824 (9,5% e duas de Lonchaeidae, Neosilba zadolicha McAlpine & Steyskal, 1982 (87,8% e uma espécie ainda não descrita, referida como Neosilba n. sp. 3 (12,2%. Anastrepha fraterculus é a espécie mais abundante nos dois municípios, sendo constatada na maioria das frutíferas coletadas. Caquizeiro e goiabeira foram os hospedeiros que apresentaram o maior índice de infestação por C. capitata. Quanto às espécies de Neosilba, a maior infestação ocorreu em frutos de goiabeira-serrana. Dos parasitoides emergidos, foram identificadas três espécies, sendo duas de Braconidae, Doryctobracon areolatus (Szépligeti, 1911 (52,6% e Opius bellus (Gahan, 1930 (27,5% e uma espécie de Figitidae, Aganaspis

Acoustic calibration apparatus for calibrating plethysmographic acoustic pressure sensors

Science.gov (United States)

Zuckerwar, Allan J. (Inventor); Davis, David C. (Inventor)

1995-01-01

An apparatus for calibrating an acoustic sensor is described. The apparatus includes a transmission material having an acoustic impedance approximately matching the acoustic impedance of the actual acoustic medium existing when the acoustic sensor is applied in actual in-service conditions. An elastic container holds the transmission material. A first sensor is coupled to the container at a first location on the container and a second sensor coupled to the container at a second location on the container, the second location being different from the first location. A sound producing device is coupled to the container and transmits acoustic signals inside the container.

Redescription of Campoletis sonorensis (Cameron, 1886) (Hymenoptera, Ichneumonidae, Campopleginae), parasitoid of Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera, Noctuidae) in Brazil.

Science.gov (United States)

Camargo, L F; Brito, R A; Penteado-Dias, A M

2015-11-01

The fall armyworm Spodoptera frugiperda (Lepidoptera; Noctuidae) is a voracious pest of numerous crops of economic importance throughout the New World. In Brazil, its larvae are attacked by several species of parasitoid wasps, making them potential candidate as biological control agents against this pest. A survey of the parasitoid fauna on S. frugiperda in maize crops throughout Brazil reveals two species of Campoletis, which are morphologicaly very similar species. In this paper we combine these data with pictures from the type material of C. sonorensis and C. flavicincta, as well as their descriptions to provide a redescription to Campoletis sonorensis (Cameron, 1886) using for this both morphological characters and DNA Barcoding (Hebert et al., 2003) information, in an attempt to help with the correct identification of the taxa to improve biological control studies.

Selectivity of different pesticides used in soybean to the eggs parasitoid Telenomus remus

OpenAIRE

Carmo, Eduardo Lima do; Bueno, Adeney de Freitas; Bueno, Regiane Cristina Oliveira de Freitas; Vieira, Simone Silva; Gobbi, Alysson Luis; Vasco, Fabrício Rodrigues

2009-01-01

A preservação dos agentes de controle biológico no agroecossistema é indispensável para o sucesso do manejo integrado de pragas. Entretanto, o controle químico de pragas ainda é indispensável em diversas culturas. Nesse contexto, a seletividade dos agrotóxicos aos inimigos naturais deve ser sempre considerada na escolha do melhor produto. Portanto, este estudo verificou o impacto causado por diferentes agrotóxicos na emergência do parasitoide de ovos Telenomus remus Nixon (Hymenoptera: Scelio...

Biological parameters and thermal requirements of the parasitoid Praon volucre (Hymenoptera: Braconidae) with Macrosiphum euphorbiae (Hemiptera: Aphididae) as host

NARCIS (Netherlands)

Conti, De B.F.; Bueno, V.H.P.; Sampaio, M.V.; Lenteren, van J.C.

2011-01-01

The effect of temperature on the biology of Praon volucre (Haliday, 1833) (Hymenoptera: Braconidae) in Macrosiphum euphorbiae (Thomas, 1878) (Hemiptera: Aphididae) hosts was studied and the thermal requirements of the parasitoid were determined. Experiments were carried out at 16, 19, 22, 25, and 28

Honey and honey-based sugars partially affect reproductive trade-offs in parasitoids exhibiting different life-history and reproductive strategies

NARCIS (Netherlands)

Harvey, Jeffrey A.; Essens, Tijl A.; Las, Rutger A.; Veen, van Cindy; Visser, B.; Ellers, J.; Heinen, R.; Gols, R.

2017-01-01

Adult dietary regimes in insects may affect egg production, fecundity and ultimately fitness. This is especially relevant in parasitoid wasps where many species serve as important biological control agents of agricultural pests. Here, we tested the effect of honey and sugar diets on daily fecundity

Three-dimensional organization of the glomeruli in the antennal lobe of the parasitoid wasps Cotesia glomerata and C. rubecula

NARCIS (Netherlands)

Smid, H.M.; Bleeker, M.A.K.; Loon, van J.J.A.; Vet, L.E.M.

2003-01-01

Two closely related parasitoid wasp species, Cotesia glomerata and C. rubecula, differ in their use of associative learning. To investigate the neural basis underlying these differences, it is necessary to describe the olfactory pathway of both wasp species. This paper focuses on the organization of

Acoustically Induced Vibration of Structures: Reverberant Vs. Direct Acoustic Testing

Science.gov (United States)

Kolaini, Ali R.; O'Connell, Michael R.; Tsoi, Wan B.

2009-01-01

Large reverberant chambers have been used for several decades in the aerospace industry to test larger structures such as solar arrays and reflectors to qualify and to detect faults in the design and fabrication of spacecraft and satellites. In the past decade some companies have begun using direct near field acoustic testing, employing speakers, for qualifying larger structures. A limited test data set obtained from recent acoustic tests of the same hardware exposed to both direct and reverberant acoustic field testing has indicated some differences in the resulting structural responses. In reverberant acoustic testing, higher vibration responses were observed at lower frequencies when compared with the direct acoustic testing. In the case of direct near field acoustic testing higher vibration responses appeared to occur at higher frequencies as well. In reverberant chamber testing and direct acoustic testing, standing acoustic modes of the reverberant chamber or the speakers and spacecraft parallel surfaces can strongly couple with the fundamental structural modes of the test hardware. In this paper data from recent acoustic testing of flight hardware, that yielded evidence of acoustic standing wave coupling with structural responses, are discussed in some detail. Convincing evidence of the acoustic standing wave/structural coupling phenomenon will be discussed, citing observations from acoustic testing of a simple aluminum plate. The implications of such acoustic coupling to testing of sensitive flight hardware will be discussed. The results discussed in this paper reveal issues with over or under testing of flight hardware that could pose unanticipated structural and flight qualification issues. Therefore, it is of paramount importance to understand the structural modal coupling with standing acoustic waves that has been observed in both methods of acoustic testing. This study will assist the community to choose an appropriate testing method and test setup in

A new species of Tamarixia Mercet (Hymenoptera, Eulophidae, parasitoid of Trioza aguacate Hollis & Martin (Hemiptera, Triozidae in Mexico

Directory of Open Access Journals (Sweden)

Zoya Yefremova

2014-01-01

Full Text Available Tamarixia aguacatensis Yefremova, sp. n. (Hymenoptera: Eulophidae: Tetrastichinae is described from Mexico as a parasitoid of the avocado psyllid, Trioza aguacate Hollis & Martin (Hemiptera: Triozidae. Trioza aguacate is a serious pest of avocado, Persea americana Miller. A key to the species of Tamarixia Mercet in Mexico is given.

Biological and Cultural Control of Olive Fruit Fly in California---Utilization of Parasitoids from USDA-APHIS-PPQ, Guatemala

Science.gov (United States)

The parasitoid Psytallia cf. concolor (Szépligeti) was reared on sterile Mediterranean fruit fly larvae at the USDA-APHIS-PPQ, Petapa Quarantine Laboratory in Guatemala and shipped to the USDA-ARS, Parlier, for wide-spread release and biological control of olive fruit fly in California. As many as 3...

Complex of primary and secondary parasitoids (Hymenoptera: Encyrtidae and Signiphoridae) of Hypogeoccoccus spp. mealybugs (Hemiptera: Pseudococcidae) in the New World

Science.gov (United States)

Parasitoids, both primary and secondary (hyperparasitoids), of Hypogeococcus spp. mealybugs (Hemiptera: Pseudococcidae) are reviewed to report results of the surveys in the New World conducted during 2009–2017 for perspective natural enemies of the Harrisia cactus mealybug, Hypogeococcus sp., which ...

Rapid Communication. Tamarixia monesus (Walker (Hym.: Eulophidae parasitoid of Bactericera tremblayi (Wagner, 1961 (Hemiptera: Triozidae in Iran

Directory of Open Access Journals (Sweden)

Lotfalizadeh Hossein

2016-08-01

Full Text Available Bactericera tremblayi (Wagner, 1961 (Hemiptera: Triozidae is reported on Brassica oleracea var. capitata (Brassicaceae in northwestern Iran. Tamarixia monesus (Walker (Hymenoptera: Chalcidoidea, Eulophidae was reared for the first time on B. tremblayi, and compared with Tamarixia tremblayi, another parasitoid of B. tremblayi. This is a new record of T. monesus from the Middle East.

Life-cycle, ultrastructure, and phylogeny of Parvilucifera corolla sp. nov. (Alveolata, Perkinsozoa), a parasitoid of dinoflagellates.

Science.gov (United States)

Reñé, Albert; Alacid, Elisabet; Figueroa, Rosa Isabel; Rodríguez, Francisco; Garcés, Esther

2017-04-01

Recent studies of marine protists have revealed parasites to be key components of marine communities. Here we describe a new species of the parasitoid genus Parvilucifera that was observed infecting the dinoflagellate Durinskia baltica in salt marshes of the Catalan coast (NW Mediterranean). In parallel, the same species was detected after the incubation of seawater from the Canary Islands (Lanzarote, NE Atlantic). The successful isolation of strains from both localities allowed description of the life cycle, ultrastructure, and phylogeny of the species. Its infection mechanism consists of a free-living zoospore that penetrates a dinoflagellate cell. The resulting trophont gradually degrades the dinoflagellate cytoplasm while growing in size. Once the host is consumed, schizogony of the parasitoid yields a sporocyte. After cytokinesis is complete, the newly formed zoospores are released into the environment and are ready to infect new host cells. A distinguishing feature of the species is the radial arrangement of its zoospores around the central area of the sporocyte during their formation. The species shows a close morphological similarity with other species of the genus, including P. infectans, P. sinerae, and P. rostrata. Copyright © 2016 Elsevier GmbH. All rights reserved.

Interior acoustic cloak

Directory of Open Access Journals (Sweden)

Wael Akl

2014-12-01

Full Text Available Acoustic cloaks have traditionally been intended to externally surround critical objects to render these objects acoustically invisible. However, in this paper, the emphasis is placed on investigating the application of the acoustic cloaks to the interior walls of acoustic cavities in an attempt to minimize the noise levels inside these cavities. In this manner, the acoustic cloaks can serve as a viable and efficient alternative to the conventional passive noise attenuation treatments which are invariably heavy and bulky. The transformation acoustics relationships that govern the operation of this class of interior acoustic cloaks are presented. Physical insights are given to relate these relationships to the reasons behind the effectiveness of the proposed interior acoustic cloaks. Finite element models are presented to demonstrate the characteristics of interior acoustic cloaks used in treating the interior walls of circular and square cavities both in the time and frequency domains. The obtained results emphasize the effectiveness of the proposed interior cloaks in eliminating the reflections of the acoustic waves from the walls of the treated cavities and thereby rendering these cavities acoustically quiet. It is important to note here that the proposed interior acoustic cloaks can find applications in acoustic cavities such as aircraft cabins and auditoriums as well as many other critical applications.

Parasitoid Quality of Gronotoma micromorpha Parasitizing Liriomyza huidobrensis on Chinese Cabbage and Soybean

Directory of Open Access Journals (Sweden)

LA DAHA

2011-09-01

Full Text Available A study with the aim to investigate the quality of Gronotoma micromorpha which attack the immature developmental stages of Liriomyza huidobrensis has been carried out. Such variables as body length measured from caput to the tip of abdomen, wing span and the length of tibia of hind leg were measured to represent parasitoid quality. The immature developmental stage period of the parasitoid was also recorded. The result indicated that a better quality Gronotoma was obtained when it was developed in the Liriomyza larvae fed on chinese cabbage with the average of 123.85 μm for body length, 253.45 μm for wing span, and 42.85 μm for the length of hind tibia, respectively. When Gronotoma was developed in the Liriomyza larvae fed on soy bean, its size became smaller with the average of 97.7 μm for body length, 214.3 μm for wing span, and 37.2 μm for the hind tibia. When it is developed in the Liriomyza on chinese cabbage host plant the immature developmental period of Gronotoma is sligthly shorter with the average of 18.4 and 17.3 days for which developed in the larvae and pupa respectively and on soy bean it become longer with the average of 19.2 days for in eggs, 19.9 days for that in the larvae. On chinese cabbage, Liriomyza tend to have bigger size for both flies and pupae.

Innate responses of the parasitoids Cotesia glomerata and C. rubecula (Hymenoptera: Braconidae) to volatiles from different plant-herbivore complexes.

NARCIS (Netherlands)

Geervliet, J.B.F.; Vet, L.E.M.; Dicke, M.

1996-01-01

To determine and compare innate preferences of the parasitoid species Cotesia glomerata and C. rubecula for different plant-herbivore complexes, long-range (1-m) foraging behavior was studied in dual-choice experiments in a wind tunnel. In this study we tested the hypothesis that naive females of

Responsive acoustic surfaces

DEFF Research Database (Denmark)

Peters, Brady; Tamke, Martin; Nielsen, Stig Anton

2011-01-01

Acoustic performance is defined by the parameter of reverberation time; however, this does not capture the acoustic experience in some types of open plan spaces. As many working and learning activities now take place in open plan spaces, it is important to be able to understand and design...... for the acoustic conditions of these spaces. This paper describes an experimental research project that studied the design processes necessary to design for sound. A responsive acoustic surface was designed, fabricated and tested. This acoustic surface was designed to create specific sonic effects. The design...... was simulated using custom integrated acoustic software and also using Odeon acoustic analysis software. The research demonstrates a method for designing space- and sound-defining surfaces, defines the concept of acoustic subspace, and suggests some new parameters for defining acoustic subspaces....

Flat acoustic lens by acoustic grating with curled slits

KAUST Repository

Peng, Pai

2014-10-01

We design a flat sub-wavelength lens that can focus acoustic wave. We analytically study the transmission through an acoustic grating with curled slits, which can serve as a material with tunable impedance and refractive index for acoustic waves. The effective parameters rely on the geometry of the slits and are independent of frequency. A flat acoustic focusing lens by such acoustic grating with gradient effective refractive index is designed. The focusing effect is clearly observed in simulations and well predicted by the theory. We demonstrate that despite the large impedance mismatch between the acoustic lens and the matrix, the intensity at the focal point is still high due to Fabry-Perot resonance.

Intraspecific competition: the role of lags between attack and death in host-parasitoid interactions.

Science.gov (United States)

Cameron, T C; Metcalfe, D; Beckerman, A P; Sait, S M

2007-05-01

Many natural enemies do not immediately kill their host, and the lag this creates between attack and host death results in mixed populations of uninfected and infected hosts. Both competition and parasitism are known to be major structuring forces in ecological communities; however, surprisingly little is known about how the competitive nature of infected hosts could affect the survival and dynamics of remaining uninfected host populations. Using a laboratory system comprising the Indian meal moth, Plodia interpunctella, and a solitary koinobiont parasitoid, Venturia canescens, we address this question by conducting replicated competition experiments between the unparasitized and parasitized classes of host larvae. For varying proportions of parasitized host larvae and competitor densities, we consider the effects of competition within (intraclass) and between (interclass) unparasitized and parasitized larvae on the survival, development time, and size of adult moths and parasitoid wasps. The greatest effects were on survival: increased competitor densities reduced survival of both parasitized and unparasitized larvae. However, unparasitized larvae survival, but not parasitized larvae survival, was reduced by increasing interclass competition. To our knowledge, this is the first experimental demonstration of the competitive superiority of parasitized over unparasitized hosts for limiting resources. We discuss possible mechanisms for this phenomenon, why it may have evolved, and its possible influence on the stability of host-parasite dynamics.

The effect of floral resources on parasitoid and host longevity

DEFF Research Database (Denmark)

Sigsgaard, Lene; Betzer, Cathrine; Naulin, Cyril

2013-01-01

The strawberry tortricid, Acleris comariana Lienig and Zeller(Lepidoptera: Tortricidae)is an important pest in Danish strawberry production. Its most common parasitoid is Copidosoma aretas (Walker) (Hymenoptera: Chalcidoidea: Encyrtidae). To identify selective flowering plants that could be used...... to increase functional biodiversity, the longevity of C. aretas and its host A. comariana was assessed on 5 flowering species: buckwheat, Fagopyrum esculentum Moench (Caryophyllales: Polygonaceae); borage, Borago officinalis L. (Boraginaceae); strawberry, Fragaria x ananassa Duchesne (Rosales: Rosaceae...... buckwheat also increased longevity of A. comariana, its longevity and survival on buckwheat, borage, and strawberry was not significantly different, so buckwheat was chosen for field experiments. A. comariana densities in the 3 fields with sown buckwheat flower strips were 0.5, 4.0, and 8.3 larvae per m per...

First survey of fruit fly (Diptera: Tephritidae and parasitoid diversity among myrtaceae fruit across the state of Bahia, Brazil

Directory of Open Access Journals (Sweden)

Lidia Nogueira Silva

2011-09-01

Full Text Available The objective of this study was to evaluate the diversity of fruit fly (Diptera: Tephritidae species that use myrtaceous fruit, particularly guava, as hosts in several localities in the state of Bahia and to determine the infestation rates, pupal viability rates, and fruit fly-parasitoid associations. Sampling of myrtaceous fruit was carried out in 24 municipalities in different regions in the state of Bahia. Four fruit fly species, Anastrepha fraterculus, Anastrepha zenildae, Anastrepha sororcula, and Ceratitis capitata were obtained from the collected fruit. Three parasitoid species (Hymenoptera: Braconidae emerged from Anastrepha larvae/pupae, Doryctobracon areolatus, Utetes anastrephae, and Asobara anastrephae. Doryctobracon areolatus emerged from A. fraterculus, A. sororcula and A. zenildae; Utetes anastrephae emerged from A. fraterculus and A. zenildae; and Asobara anastrephae emerged from A. fraterculus. Fruit fly and myrtaceous fruit associations are reported for the first time in several municipalities in the state of Bahia. A. zenildae was found infesting Syzygium malaccense for the first time in Brazil.

Parametric Room Acoustic workflows with real-time acoustic simulation

DEFF Research Database (Denmark)

Parigi, Dario

2017-01-01

The paper investigates and assesses the opportunities that real-time acoustic simulation offer to engage in parametric acoustics workflow and to influence architectural designs from early design stages......The paper investigates and assesses the opportunities that real-time acoustic simulation offer to engage in parametric acoustics workflow and to influence architectural designs from early design stages...

Effects on microhymenopteran progeny of different host exposure periods (Chrysomya megacephala, Calliphoridae to the parasitoid wasp Nasonia vitripennis (Hymenoptera: Pteromalidae

Directory of Open Access Journals (Sweden)

Renata da Silva Mello

2010-02-01

Full Text Available To test the assumption that exposure of the host to parasitoid for long periods could provoke superparasitism, the aim of this work was to test the consequences on the immature development time, productivity of parasitoids per pupa, sex ratio and rate of parasitism of Nasonia vitripennis bred in Chrysomya megacephala pupae. Each individual pupa was placed in a glass tube with one parasitoid female for 24, 48, 72 and 96 h period of exposure, under controlled laboratory conditions. Twenty replicates of each period were performed. ANOVA with a 5% significance level was applied. The 72 h exposure caused the immature development time to increase. The mean parasitoids emergence per pupa did not vary significantly with the time of exposure. There were a significantly higher number of females than males and a trend in sex ratio deviation towards the females in all of the treatments. An increase in the number of unviable pupae rates were observed with increased exposure time.Para testar a hipótese que longos períodos de exposição do hospedeiro ao parasitóide podem ocasionar o superparasitismo, o presente estudo teve como objetivo testar as conseqüências sobre o tempo de desenvolvimento do imaturo, a produtividade de parasitóides, razão sexual e taxa de parasitismo de Nasonia vitripennis criadas em pupas de Chrysomya megacephala. Cada pupa foi individualizada e alocada em um tudo de ensaio com uma fêmea de N. vitripennis por 24, 48, 72 ou 96 h, sob condições laboratoriais controladas. Foram realizadas 20 réplicas para cada período de exposição. ANOVA com significância de 5 % foi aplicada. A exposição de 72 h causou um aumento no tempo desenvolvimento. A média de emergência de parasitóides não variou significativamente entre os tempos de exposição. Houve um número significativamente maior de fêmeas e uma tendência ao desvio da razão sexual para fêmeas em todos os tratamentos. Foi verificado um aumento no número de pupas invi

Effects of rearing conditions on reproduction of Spathius agrili (Hymenoptera: Braconidae), a parasitoid of the emerald ash borer (Coleoptera: Buprestidae).

Science.gov (United States)

Gould, Juli R; Ayer, Tracy; Fraser, Ivich

2011-04-01

Spathius agrili Yang (Hymenoptera: Braconidae) can be successfully reared on emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), larvae feeding in chambers drilled in small ash twigs that are wrapped with floral tape. Females maintained in groups with males for one week can receive enough sperm for production of female progeny throughout their lives. Volatiles released by emerald ash borer adults feeding on ash foliage increased parasitoid fecundity over ash foliage alone or no stimulus. The temperature at which the parasitoids were reared ranged from 20 to 25 degrees C in a daily cycle; however, raising the daily maximum temperature to 28 degrees C did not affect parasitoid longevity or fecundity. Adult females lived between 12 and 127 d, with an average of 60.8 +/- 4.5 d. Males lived slightly longer, with an average of 66 +/- 4.5 d. The first clutch of eggs was laid when the female was between 2 and 42 d old, with the average preoviposition period lasting 11.4 +/- 1.4 or 19.5 +/- 2.0 d in 2007 and 2009 trials, respectively. A higher proportion of the emerald ash borer larvae were feeding and thus attractive to parasitoids in the 2009 trial, and female S. agrili laid an average of 9.5 +/- 1.0 clutches containing 5.4 +/- 0.2 eggs, for an average of 51.2 eggs per female. Approximately three quarters of the progeny were female. The number of eggs per clutch was significantly greater when deposited on larger emerald ash borer larvae, further highlighting the need for quality larvae in rearing. Chilling S. agrili pupae at 10 degrees C to stockpile them for summer release was not successful; chilling resulted in lower survival and lower fecundity of emerging progeny. Female S. agrili proved capable of attacking emerald ash borer larvae through even the thickest bark of an ash tree that was 30-cm diameter at breast height. Even emerald ash borer larvae that were creating overwintering chambers in the outer sapwood of the tree were successfully

Classical biological control of an invasive forest pest: a world perspective of the management of Sirex noctilio using the parasitoid Ibalia leucospoides (Hymenoptera: Ibaliidae).

Science.gov (United States)

Fischbein, D; Corley, J C

2015-02-01

Classical biological control is a key method for managing populations of pests in long-lived crops such as plantation forestry. The execution of biological control programmes in general, as the evaluation of potential natural enemies remains, to a large extent, an empirical endeavour. Thus, characterizing specific cases to determine patterns that may lead to more accurate predictions of success is an important goal of the much applied ecological research. We review the history of introduction, ecology and behaviour of the parasitoid Ibalia leucospoides. The species is a natural enemy of Sirex noctilio, one of the most important pests of pine afforestation worldwide. We use an invasion ecology perspective given the analogy between the main stages involved in classical biological control and the biological invasion processes. We conclude that success in the establishment, a common reason of failure in biocontrol, is not a limiting factor of success by I. leucospoides. A mismatch between the spread capacity of the parasitoid and that of its host could nevertheless affect control at a regional scale. In addition, we suggest that given its known life history traits, this natural enemy may be a better regulator than suppressor of the host population. Moreover, spatial and temporal refuges of the host population that may favour the local persistence of the interaction probably reduce the degree to which S. noctilio population is suppressed by the parasitoid. We emphasize the fact that some of the biological attributes that promote establishment may negatively affect suppression levels achieved. Studies on established non-native pest-parasitoid interactions may contribute to defining selection criteria for classical biological control which may prove especially useful in integrated pest management IPM programmes of invasive forest insects.

Adaptations to different habitats in sexual and asexual populations of parasitoid wasps: a meta-analysis

OpenAIRE

Amat, I; Kacelnik, A; van Alphen, JJM; Desouhant, E; Bernstein, C

2017-01-01

Background Coexistence of sexual and asexual populations remains a key question in evolutionary ecology. We address the question how an asexual and a sexual form of the parasitoid Venturia canescens can coexist in southern Europe. We test the hypothesis that both forms are adapted to different habitats within their area of distribution. Sexuals inhabit natural environments that are highly unpredictable, and where density of wasps and their hosts is low and patchily distributed. Asexuals in...

Structure elucidation of female-specific volatiles released by the parasitoid wasp Trichogramma turkestanica (Hymenoptera: Trichogrammatidae

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Armin Tröger

2014-04-01

Full Text Available Females of the parasitoid wasp Trichogramma turkestanica produce the putative polydeoxypropionates (2E,4E,6S,8S,10S-4,6,8,10-tetramethyltrideca-2,4-diene and (2E,4E,6S,8S,10S-4,6,8,10-tetramethyltrideca-2,4-dien-1-ol or their enantiomers as sex specific volatiles. The structures were assigned on the basis of GC–MS investigations using synthetic reference compounds.

Redescription of Campoletis sonorensis (Cameron, 1886 (Hymenoptera, Ichneumonidae, Campopleginae, parasitoid of Spodoptera frugiperda (J. E. Smith, 1797 (Lepidoptera, Noctuidae in Brazil

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L. F. Camargo

Full Text Available Abstract The fall armyworm Spodoptera frugiperda (Lepidoptera; Noctuidae is a voracious pest of numerous crops of economic importance throughout the New World. In Brazil, its larvae are attacked by several species of parasitoid wasps, making them potential candidate as biological control agents against this pest. A survey of the parasitoid fauna on S. frugiperda in maize crops throughout Brazil reveals two species of Campoletis, which are morphologicaly very similar species. In this paper we combine these data with pictures from the type material of C. sonorensis and C. flavicincta, as well as their descriptions to provide a redescription to Campoletis sonorensis (Cameron, 1886 using for this both morphological characters and DNA Barcoding (Hebert et al., 2003 information, in an attempt to help with the correct identification of the taxa to improve biological control studies.

Monitoring the establishment and flight phenology of parasitoids of emerald ash borer (Coleoptera: Buprestidae) in Michigan by using sentinel eggs and larvae

Science.gov (United States)

Kristopher J. Abell; Leah S. Bauer; Deborah L. Miller; Jian J. Duan; Roy G. Van Driesche

2016-01-01

The emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is an important invasive pest of ash (Fraxinus) trees in North America. Two larval parasitoid species, Tetrastichus planipennisi Yang (Hymenoptera: Eulophidae) and Spathius agrili Yang (Hymenoptera:...

A numerical study on acoustic behavior in gas turbine combustor with acoustic resonator

International Nuclear Information System (INIS)

Park, I Sun; Sohn, Chae Hoon

2005-01-01

Acoustic behavior in gas turbine combustor with acoustic resonator is investigated numerically by adopting linear acoustic analysis. Helmholtz-type resonator is employed as acoustic resonator to suppress acoustic instability passively. The tuning frequency of acoustic resonator is adjusted by varying its length. Through harmonic analysis, acoustic-pressure responses of chamber to acoustic excitation are obtained and the resonant acoustic modes are identified. Acoustic damping effect of acoustic resonator is quantified by damping factor. As the tuning frequency of acoustic resonator approaches the target frequency of the resonant mode to be suppressed, mode split from the original resonant mode to lower and upper modes appears and thereby complex patterns of acoustic responses show up. Considering mode split and damping effect as a function of tuning frequency, it is desirable to make acoustic resonator tuned to broad-band frequencies near the maximum frequency of those of the possible upper modes

Acoustical Imaging

CERN Document Server

Litniewski, Jerzy; Kujawska, Tamara; 31st International Symposium on Acoustical Imaging

2012-01-01

The International Symposium on Acoustical Imaging is a unique forum for advanced research, covering new technologies, developments, methods and theories in all areas of acoustics. This interdisciplinary Symposium has been taking place continuously since 1968. In the course of the years the proceedings volumes in the Acoustical Imaging Series have become a reference for cutting-edge research in the field. In 2011 the 31st International Symposium on Acoustical Imaging was held in Warsaw, Poland, April 10-13. Offering both a broad perspective on the state-of-the-art as well as  in-depth research contributions by the specialists in the field, this Volume 31 in the Series contains an excellent collection of papers in six major categories: Biological and Medical Imaging Physics and Mathematics of Acoustical Imaging Acoustic Microscopy Transducers and Arrays Nondestructive Evaluation and Industrial Applications Underwater Imaging

Parasitoid diversity (Hymenoptera: Braconidae and Figitidae on frugivorous larvae (Diptera: Tephritidae and Lonchaeidae at Adolpho Ducke Forest Reserve, Central Amazon Region, Manaus, Brazil

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SGM. Costa

Full Text Available This study aimed to identify parasitoid species of frugivorous larvae and to describe the tritrophic interactions involving wild fruits, frugivorous insects and their natural enemies at Adolpho Ducke Forest Reserve (RFAD (Manaus, AM, Brazil. Collections were performed in four 1 km² quadrants in the corners of the RFAD. The wild fruits were collected inside the forest in access trails leading to each collection area and in trails that surrounded the quadrants, up to five metres from the trail on each side. The fruits were placed in plastic containers covered with thin fabric, with a vermiculite layer on the base to allow the emergence of flies or parasitoids. Seven Braconidae species were collected, distributed among Opiinae: Doryctobracon areolatus (Szépligeti, 1911, Utetes anastrephae (Viereck, 1913, and Opius sp., and Alysiinae: Asobara anastrephae (Muesebeck, 1958, Phaenocarpa pericarpa Wharton and Carrejo, 1999, Idiasta delicata Papp, 1969, and Asobara sp. Parasitism rates by braconids and figitids are presented. Doryctobracon areolatus was the most frequent, parasitizing the highest number of fly species, and showing the highest parasitism percentage in larvae feeding on Micropholis williamii fruits. The collected figitids belong to Aganaspis nordlanderi Wharton, 1998 and A. pelleranoi (Brethes, 1924. All 15 tritrophic associations are new records for the Brazilian Amazon region. The RFAD is an important natural reservoir of frugivorous larvae parasitoids.

Effects of Temperature and Photoperiod on the Reproductive Biology and Diapause of Oobius agrili (Hymenoptera: Encyrtidae), an Egg Parasitoid of Emerald Ash Borer (Coleoptera: Buprestidae).

Science.gov (United States)

Hoban, J; Duan, J J; Hough-Goldstein, J

2016-04-25

Oobius agrili Zhang and Huang (Hymenoptera: Encyrtidae) is a solitary egg parasitoid of the invasive emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), and has been introduced to the United States for classical biological control. We characterized the weekly survivorship, fecundity, and diapause patterns of both diapaused and nondiapaused populations of O. agrili under four different temperature-photophase combinations: 30°C (warm) and 20°C (cold) temperatures with both long-day (16 h) and short-day (8 h) photophase. Results of this study showed that regardless of the length of photophase, parental parasitoids of both diapaused and nondiapaused O. agrili survived significantly longer at 20°C than at 30°C. Both populations also laid their eggs faster at 30°C compared with those at 20°C. Higher proportions of the progeny produced by both populations of O. agrili were induced into diapause by short-day (8 h) photophase, regardless of rearing temperature. In addition, the diapaused parasitoids in the short-day photophase treatment at both warm and cold temperatures produced increasing proportions of diapaused progeny over time, whereas no significant differences were observed in the proportions of diapaused progeny by the nondiapaused parasitoids over different sampling times. These findings suggest that O. agrili should be continuously reared under warm temperature and long-day photoperiod (to avoid diapause for increased reproduction). In addition, we recommend that diapaused adults be used for field releases in early summer when temperatures are still relatively low (∼20°C) and host eggs are available so that they can produce multiple generations prior to overwintering. Published by Oxford University Press on behalf of Entomological Society of America 2015. This work is written by US Government employees and is in the public domain in the United States.

Topological Acoustics

Science.gov (United States)

Yang, Zhaoju; Gao, Fei; Shi, Xihang; Lin, Xiao; Gao, Zhen; Chong, Yidong; Zhang, Baile

2015-03-01

The manipulation of acoustic wave propagation in fluids has numerous applications, including some in everyday life. Acoustic technologies frequently develop in tandem with optics, using shared concepts such as waveguiding and metamedia. It is thus noteworthy that an entirely novel class of electromagnetic waves, known as "topological edge states," has recently been demonstrated. These are inspired by the electronic edge states occurring in topological insulators, and possess a striking and technologically promising property: the ability to travel in a single direction along a surface without backscattering, regardless of the existence of defects or disorder. Here, we develop an analogous theory of topological fluid acoustics, and propose a scheme for realizing topological edge states in an acoustic structure containing circulating fluids. The phenomenon of disorder-free one-way sound propagation, which does not occur in ordinary acoustic devices, may have novel applications for acoustic isolators, modulators, and transducers.

High transmission acoustic focusing by impedance-matched acoustic meta-surfaces

KAUST Repository

Al Jahdali, Rasha

2016-01-19

Impedance is an important issue in the design of acoustic lenses because mismatched impedance is detrimental to real focusing applications. Here, we report two designs of acoustic lenses that focus acoustic waves in water and air, respectively. They are tailored by acoustic meta-surfaces, which are rigid thin plates decorated with periodically distributed sub-wavelength slits. Their respective building blocks are constructed from the coiling-up spaces in water and the layered structures in air. Analytic analysis based on coupled-mode theory and transfer matrix reveals that the impedances of the lenses are matched to those of the background media. With these impedance-matched acoustic lenses, we demonstrate the acoustic focusing effect by finite-element simulations.

High transmission acoustic focusing by impedance-matched acoustic meta-surfaces

KAUST Repository

Al Jahdali, Rasha; Wu, Ying

2016-01-01

Impedance is an important issue in the design of acoustic lenses because mismatched impedance is detrimental to real focusing applications. Here, we report two designs of acoustic lenses that focus acoustic waves in water and air, respectively. They are tailored by acoustic meta-surfaces, which are rigid thin plates decorated with periodically distributed sub-wavelength slits. Their respective building blocks are constructed from the coiling-up spaces in water and the layered structures in air. Analytic analysis based on coupled-mode theory and transfer matrix reveals that the impedances of the lenses are matched to those of the background media. With these impedance-matched acoustic lenses, we demonstrate the acoustic focusing effect by finite-element simulations.

Field-cage evaluation of the parasitoid Phymastichus coffea LaSalle (Hymenoptera: Eulophidae) as a natural enemy of the coffee berry borer

Science.gov (United States)

Phymastichus coffea (Hymenoptera: Eulophidae) is an African parasitoid that has been imported to Mexico and other Latin American countries for the biological control of the coffee berry borer, Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae: Scolytinae). As a part of the evaluation of this ...

Selection of Trichogramma strains and determination of number of parasitoids to be released to control Gymnandrosoma aurantianum Lima (Lepidoptera, Tortricidae); Selecao de linhagens de Trichogramma (Hymenoptera, Trichogrammatidae) e determinacao do numero de parasitoides a ser liberado para o controle de Gymnandrosoma aurantianum Lima (Lepidoptera, Tortricidae)

Energy Technology Data Exchange (ETDEWEB)

Molina, Rosa Maria da Silva; Parra, Jose Roberto Postali [Escola Superior de Agricultura Luiz de Queiroz (ESALQ/USP), Piracicaba, SP (Brazil). Dept. de Entomologia, Fitopatologia e Zoologia Agricola], e-mail: rmsmolina@ig.com.br, e-mail: jrpparra@esalq.usp.br

2006-12-15

In order to select Trichogramma strains to control G. aurantianum, the biological characteristics of 13 Trichogramma species/strains were evaluated. After selection, the ideal number of T. pretiosum (G18 strain) to be released per G. aurantianum egg was determined in greenhouse tests. The selection test for species/strains was carried out in an incubator adjusted to 25 +- 1 deg C, RH 70 +- 10%, and a 14 h photo phase. The ideal number of parasitoids was estimated in cages covered with a piece of voile-type fabric. The cycle duration for the 13 Trichogramma species/strains varied from 10.2 to 11.9 days. The Atp strain (T. atopovirilia) showed greater parasitism capacity, with an average of 23.3 parasitized eggs and 77.5% parasitism in 24 hours. The G18 strain (T. pretiosum) came next, with an average of 16.8 parasitized eggs and 56.1% parasitism during the same time interval. The emergency, longevity of males, and sex ratio for the 13 species/strains were similar. The number of adults emerged per egg was 1.8 for strains G11 (T. pretiosum) and Br10 (T. bruni), which were different from the G3 strain (T. pretiosum) only, with 1.3 adults per egg. With regard to female longevity, distinct values were observed only between T. pretiosum strains Tp and L2, with 6.3 and 9.3 days, respectively. Under greenhouse conditions, the estimated ratio of 36 T. pretiosum parasitoids per G. aurantianum egg allowed the highest percentage of parasitism (89%). Therefore, Trichogramma spp. has a potential to control G. aurantianum, as long as a large number of parasitoids is released per unit area. (author)

Accidental genetic engineers: horizontal sequence transfer from parasitoid wasps to their Lepidopteran hosts.

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Sean E Schneider

Full Text Available We show here that 105 regions in two Lepidoptera genomes appear to derive from horizontally transferred wasp DNA. We experimentally verified the presence of two of these sequences in a diverse set of silkworm (Bombyx mori genomes. We hypothesize that these horizontal transfers are made possible by the unusual strategy many parasitoid wasps employ of injecting hosts with endosymbiotic polydnaviruses to minimize the host's defense response. Because these virus-like particles deliver wasp DNA to the cells of the host, there has been much interest in whether genetic information can be permanently transferred from the wasp to the host. Two transferred sequences code for a BEN domain, known to be associated with polydnaviruses and transcriptional regulation. These findings represent the first documented cases of horizontal transfer of genes between two organisms by a polydnavirus. This presents an interesting evolutionary paradigm in which host species can acquire new sequences from parasitoid wasps that attack them. Hymenoptera and Lepidoptera diverged ∼300 MYA, making this type of event a source of novel sequences for recipient species. Unlike many other cases of horizontal transfer between two eukaryote species, these sequence transfers can be explained without the need to invoke the sequences 'hitchhiking' on a third organism (e.g. retrovirus capable of independent reproduction. The cellular machinery necessary for the transfer is contained entirely in the wasp genome. The work presented here is the first such discovery of what is likely to be a broader phenomenon among species affected by these wasps.

Poneromorph Ants Associated with Parasitoid Wasps of the Genus Kapala Cameron (Hymenoptera: Eucharitidae in French Guiana

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Jean-Paul Lachaud

2012-01-01

Full Text Available Eucharitid wasps are specific, specialized parasitoids of ants. The genus Kapala Cameron is the most common in the Neotropics but few species are described, and information dealing with their biology, behavior and host associations is scarce. Numerous poneromorph ant colonies were inspected over 4 collection surveys in French Guiana. A diverse fauna of parasites and parasitoids was found, including mermithid nematodes, flies, eucharitids, and another gregarious endoparasitoid wasp. Five new host associations for Kapala are reported, all of them involving medium- to large-size poneromorph ant species from 4 genera: Ectatomma brunneum Fr. Smith, Gnamptogenys tortuolosa (Fr. Smith, Odontomachus haematodus (L., O. mayi Mann, and Pachycondyla verenae (Forel. Three other associations involving O. hastatus (Fabr., P. apicalis (Latreille, and P. stigma (Fabr., already reported for other countries but new for French Guiana, are confirmed. The data extend the number of hosts for Kapala to 24 ant species from 7 genera. The high diversity of the ant host genera associated with Kapala, combined with the fact that these ant genera are the most widely distributed among Neotropical poneromorph ants, could account for the dominant status of the genus Kapala among the eucharitine wasps of Central and South America.

MODIFICACIÓN AL PROCESO DE PRODUCCIÓN MASIVA DE LOS PARASITOIDES Catolaccus grandis Y Catolaccus hunteri

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Marco Antonio Reyes-Rosas

2010-01-01

Full Text Available El presente estudio se realizó con el objetivo de modificar la tecnología de producción masiva de Catolaccus grandis y Catolaccus hunteri, himenópteros parasitoides de Anthonomus grandis el picudo del algodonero en Tamaulipas, México en el 2002. Se determinó la eficiencia del papel toalla para el secado de manos, en el sellamiento de cápsulas moldeadas en cera de hidrocarburos y poliolefina (LCHP, donde se confina al huésped, y evaluar la efectividad del gorgojo del garbanzo Callosobruchus maculatus como hospedante facticio para la cría de ambos parasitoides. Hubo producción masiva de C. grandis y C. hunteri utilizando C. maculatus como huésped y el papel toalla fue efectivo para sellar los orificios de las cápsulas moldeadas en LCHP. La producción masiva de C. grandis y C. hunteri mediante C. maculatus, contribuyó a incrementar la seguridad y facilidad del proceso, además de una significativa reducción de costos. El papel toalla en el sellado de los orificios de las cápsulas moldeadas en LCHP, redujo en un 50% por m2 los costos del proceso, sin afectar la eficiencia del parasitismo y emergencia de C. grandis.

Vibro-acoustics

CERN Document Server

Nilsson, Anders

2015-01-01

This three-volume book gives a thorough and comprehensive presentation of vibration and acoustic theories. Different from traditional textbooks which typically deal with some aspects of either acoustic or vibration problems, it is unique of this book to combine those two correlated subjects together. Moreover, it provides fundamental analysis and mathematical descriptions for several crucial phenomena of Vibro-Acoustics which are quite useful in noise reduction, including how structures are excited, energy flows from an excitation point to a sound radiating surface, and finally how a structure radiates noise to a surrounding fluid. Many measurement results included in the text make the reading interesting and informative. Problems/questions are listed at the end of each chapter and the solutions are provided. This will help the readers to understand the topics of Vibro-Acoustics more deeply. The book should be of interest to anyone interested in sound and vibration, vehicle acoustics, ship acoustics and inter...

Acoustics an introduction

CERN Document Server

Kuttruff, Heinrich

2006-01-01

This definitive textbook provides students with a comprehensive introduction to acoustics. Beginning with the basic physical ideas, Acoustics balances the fundamentals with engineering aspects, applications and electroacoustics, also covering music, speech and the properties of human hearing. The concepts of acoustics are exposed and applied in:room acousticssound insulation in buildingsnoise controlunderwater sound and ultrasoundScientifically thorough, but with mathematics kept to a minimum, Acoustics is the perfect introduction to acoustics for students at any level of mechanical, electrical or civil engineering courses and an accessible resource for architects, musicians or sound engineers requiring a technical understanding of acoustics and their applications.

Combined Non-Target Effects of Insecticide and High Temperature on the Parasitoid Bracon nigricans.

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Khaled Abbes

Full Text Available We studied the acute toxicity and the sublethal effects, on reproduction and host-killing activity, of four widely used insecticides on the generalist parasitoid Bracon nigricans (Hymenoptera: Braconidae, a natural enemy of the invasive tomato pest, Tuta absoluta (Lepidoptera: Gelechiidae. Laboratory bioassays were conducted applying maximum insecticide label rates at three constant temperatures, 25, 35 and 40°C, considered as regular, high and very high, respectively. Data on female survival and offspring production were used to calculate population growth indexes as a measure of population recovery after pesticide exposure. Spinetoram caused 80% mortality at 25°C and 100% at higher temperatures, while spinosad caused 100% mortality under all temperature regimes. Cyantraniliprole was slightly toxic to B. nigricans adults in terms of acute toxicity at the three temperatures, while it did not cause any sublethal effects in egg-laying and host-killing activities. The interaction between the two tested factors (insecticide and temperature significantly influenced the number of eggs laid by the parasitoid, which was the lowest in the case of females exposed to chlorantraniliprole at 35°C. Furthermore, significantly lower B. nigricans demographic growth indexes were estimated for all the insecticides under all temperature conditions, with the exception of chlorantraniliprole at 25°C. Our findings highlight an interaction between high temperatures and insecticide exposure, which suggests a need for including natural stressors, such as temperature, in pesticide risk assessments procedures.

Toxicity risk of insecticides to the insect egg parasitoid Trichogramma evanescens Westwood (Hymenoptera: Trichogrammatidae).

Science.gov (United States)

Wang, Yanhua; Wu, Changxing; Cang, Tao; Yang, Lizhi; Yu, Weihua; Zhao, Xueping; Wang, Qiang; Cai, Leiming

2014-03-01

Natural populations of Trichogramma evanescens contribute to the control of lepidopterous pests. The toxic effects of insecticides have been extensively reported on trichogrammatids, but are largely unknown on T. evanescens. In this study, the toxicities of seven classes of chemicals against the parasitoid were investigated. Among these classes, organophosphates and carbamates exhibited the highest levels of intrinsic toxicity, with LC50 values ranging from 0.025 (0.023-0.028) to 2.20 (1.71-3.09) and from 0.040 (0.032-0.053) to 1.84 (1.53-2.30) mg AI L(-1) respectively. Among the phenylpyrazoles, only ethiprole can be considered to be less toxic in the group. Avermectins, pyrethroids and neonicotinoids were less toxic, with LC50 values ranging from 1.29 to 2.57, from 2.26 to 14.03 and from 1.12 to 239.1 mg AI L(-1) respectively. In contrast, insect growth regulators (IGRs) showed the lowest toxicity to the parasitoid, with LC50 values ranging from 3383 (2406-5499) to 5650 (4228-8579) mg AI L(-1) . The results of risk quotient analysis indicated that neonicotinoids, avermectins, pyrethroids and IGRs were less hazardous, but phenylpyrazoles (except for ethiprole), organophosphates and carbamates were slightly to moderately or dangerously toxic to T. evanescens. The present results provide informative data for implementing biological and chemical control strategies in integrated pest management of lepidopterans. © 2013 Society of Chemical Industry.

Interior acoustic cloak

OpenAIRE

Wael Akl; A. Baz

2014-01-01

Acoustic cloaks have traditionally been intended to externally surround critical objects to render these objects acoustically invisible. However, in this paper, the emphasis is placed on investigating the application of the acoustic cloaks to the interior walls of acoustic cavities in an attempt to minimize the noise levels inside these cavities. In this manner, the acoustic cloaks can serve as a viable and efficient alternative to the conventional passive noise attenuation treatments which a...

Explaining variations in the diversity of parasitoid assemblages in a biosphere reserve of Mexico: evidence from vegetation, land management and seasonality.

Science.gov (United States)

González-Moreno, A; Bordera, S; Leirana-Alcocer, J; Delfín-González, H; Ballina-Gómez, H S

2017-11-23

Insect fauna biodiversity in natural protected areas has not been thoroughly studied. Therefore, the aim of this work was to assess whether and how vegetation types, land management and seasonality influence the diversity of Ichneumonidae (Hymenoptera) in the Ría Lagartos Biosphere Reserve (Mexico). A sampling programme was conducted using Malaise traps from 2008 to 2009 in three vegetation types, each with two conservation zones (core and buffer zones). Three seasons were considered: rainy, dry and north-winds (isolated storms from November to February). A total of 336 species were identified. Rarefaction and Generalized Linear Model indicated higher species richness and abundance, respectively, in the buffer zone of the dry forest; possible explanations for this finding include the intermediate disturbance hypothesis, wherein diversity can be higher in sites where disturbance is not very frequent or very intense, and the 'enemies hypothesis', wherein structural complexity and high plant diversity favour increased predators or, in this case, parasitoids. Diversity was higher during the rainy season, which may have been due to the higher availability of resources. Vegetation and management had a positive impact on the Coc (attack cocoons and pupae) and Myc (attack concealed larvae living in the fruiting bodies of mushrooms) parasitoid guilds. Members of the Coc guild are generalist parasitoids, which may be favoured in complex vegetation with a high richness of potential hosts and non-hosts. The Myc guild requires certain environmental conditions that promote fungal growth, such as humidity, that is absent in the other vegetation types of savannah and coastal dune scrubland.

European science in the Enlightenment and the discovery of the insect parasitoid life cycle in The Netherlands and Great Britain

NARCIS (Netherlands)

Lenteren, van J.C.; Godfray, H.C.J.

2005-01-01

The authors most frequently credited for the European discovery of the parasitoid life cycle are Antoni van Leeuwenhoek, John Ray and Antonio Vallisnieri around the year 1700. Many other European authors published works on entomology in the 17th century and mentioned insects that we now recognize as

Field-Cage Methodology for Evaluating Climatic Suitability for Introduced Wood-Borer Parasitoids: Preliminary Results from the Emerald Ash Borer System

Science.gov (United States)

Ulyshen, Michael D.; Duan, Jian J.; Bauer, Leah S.; Gould, Juli; Taylor, Phil; Bean, Dick; Holko, Carol; Driesche, Roy Van

2011-01-01

Field-cage methods were developed to evaluate the abilities of Tetrastichus planipennisi Yang (Hymenoptera: Eulophidae) and Spathius agrili Yang (Hymenoptera: Braconidae), biocontrol agents of Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), to parasitize, develop and overwinter following three late-season releases at both a northern (Michigan) and a southern (Maryland) location within the current North American range of A. planipennis. In August, September and October of 2009, five young green ash trees were selected at each location. Tetrastichus planipennisi and S. agrili were each randomly assigned to one of two cages attached to each tree, surrounding separate sections of trunk in which late-instar A. planipennis had been inserted. The following April, the caged trunk sections were dissected to determine the fate of each A. planipennis larva and the developmental stages of all recovered parasitoid progeny. At both locations, T. planipennisi and S. agrili were able to parasitize hosts and successfully overwinter (i.e., reach adulthood the following spring). For T. planipennisi, successful parasitism (i.e., parasitoid progeny reached adulthood) occurred for all caged releases in Maryland, but only for the August and September releases in Michigan. At both locations, percent parasitism by T. planipennisi was higher in August and September than in October. For S. agrili, successful parasitism occurred for all caged releases in Maryland, but only for the August release in Michigan. In Maryland, percent parasitism by S. agrili in August and September was higher than in October. The caging method described here should be useful in determining the climatic suitability of other regions before proceeding with large-scale releases of either species and may have utility in other wood-borer parasitoid systems as well. PMID:22233133

Selection of Trichogramma strains and determination of number of parasitoids to be released to control Gymnandrosoma aurantianum Lima (Lepidoptera, Tortricidae)

International Nuclear Information System (INIS)

Molina, Rosa Maria da Silva; Parra, Jose Roberto Postali

2006-01-01

In order to select Trichogramma strains to control G. aurantianum, the biological characteristics of 13 Trichogramma species/strains were evaluated. After selection, the ideal number of T. pretiosum (G18 strain) to be released per G. aurantianum egg was determined in greenhouse tests. The selection test for species/strains was carried out in an incubator adjusted to 25 +- 1 deg C, RH 70 +- 10%, and a 14 h photo phase. The ideal number of parasitoids was estimated in cages covered with a piece of voile-type fabric. The cycle duration for the 13 Trichogramma species/strains varied from 10.2 to 11.9 days. The Atp strain (T. atopovirilia) showed greater parasitism capacity, with an average of 23.3 parasitized eggs and 77.5% parasitism in 24 hours. The G18 strain (T. pretiosum) came next, with an average of 16.8 parasitized eggs and 56.1% parasitism during the same time interval. The emergency, longevity of males, and sex ratio for the 13 species/strains were similar. The number of adults emerged per egg was 1.8 for strains G11 (T. pretiosum) and Br10 (T. bruni), which were different from the G3 strain (T. pretiosum) only, with 1.3 adults per egg. With regard to female longevity, distinct values were observed only between T. pretiosum strains Tp and L2, with 6.3 and 9.3 days, respectively. Under greenhouse conditions, the estimated ratio of 36 T. pretiosum parasitoids per G. aurantianum egg allowed the highest percentage of parasitism (89%). Therefore, Trichogramma spp. has a potential to control G. aurantianum, as long as a large number of parasitoids is released per unit area. (author)

Acoustic energy harvesting based on a planar acoustic metamaterial

Science.gov (United States)

Qi, Shuibao; Oudich, Mourad; Li, Yong; Assouar, Badreddine

2016-06-01

We theoretically report on an innovative and practical acoustic energy harvester based on a defected acoustic metamaterial (AMM) with piezoelectric material. The idea is to create suitable resonant defects in an AMM to confine the strain energy originating from an acoustic incidence. This scavenged energy is converted into electrical energy by attaching a structured piezoelectric material into the defect area of the AMM. We show an acoustic energy harvester based on a meta-structure capable of producing electrical power from an acoustic pressure. Numerical simulations are provided to analyze and elucidate the principles and the performances of the proposed system. A maximum output voltage of 1.3 V and a power density of 0.54 μW/cm3 are obtained at a frequency of 2257.5 Hz. The proposed concept should have broad applications on energy harvesting as well as on low-frequency sound isolation, since this system acts as both acoustic insulator and energy harvester.

Panel acoustic contribution analysis.

Science.gov (United States)

Wu, Sean F; Natarajan, Logesh Kumar

2013-02-01

Formulations are derived to analyze the relative panel acoustic contributions of a vibrating structure. The essence of this analysis is to correlate the acoustic power flow from each panel to the radiated acoustic pressure at any field point. The acoustic power is obtained by integrating the normal component of the surface acoustic intensity, which is the product of the surface acoustic pressure and normal surface velocity reconstructed by using the Helmholtz equation least squares based nearfield acoustical holography, over each panel. The significance of this methodology is that it enables one to analyze and rank relative acoustic contributions of individual panels of a complex vibrating structure to acoustic radiation anywhere in the field based on a single set of the acoustic pressures measured in the near field. Moreover, this approach is valid for both interior and exterior regions. Examples of using this method to analyze and rank the relative acoustic contributions of a scaled vehicle cabin are demonstrated.

Springer Handbook of Acoustics

CERN Document Server

Rossing, Thomas D

2007-01-01

Acoustics, the science of sound, has developed into a broad interdisciplinary field encompassing the academic disciplines of physics, engineering, psychology, speech, audiology, music, architecture, physiology, neuroscience, and others. The Springer Handbook of Acoustics is an unparalleled modern handbook reflecting this richly interdisciplinary nature edited by one of the acknowledged masters in the field, Thomas Rossing. Researchers and students benefit from the comprehensive contents spanning: animal acoustics including infrasound and ultrasound, environmental noise control, music and human speech and singing, physiological and psychological acoustics, architectural acoustics, physical and engineering acoustics, signal processing, medical acoustics, and ocean acoustics. This handbook reviews the most important areas of acoustics, with emphasis on current research. The authors of the various chapters are all experts in their fields. Each chapter is richly illustrated with figures and tables. The latest rese...

Adaptive selection on bracovirus genomes drives the specialization of Cotesia parasitoid wasps.

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Séverine Jancek

Full Text Available The geographic mosaic of coevolution predicts parasite virulence should be locally adapted to the host community. Cotesia parasitoid wasps adapt to local lepidopteran species possibly through their symbiotic bracovirus. The virus, essential for the parasitism success, is at the heart of the complex coevolutionary relationship linking the wasps and their hosts. The large segmented genome contained in the virus particles encodes virulence genes involved in host immune and developmental suppression. Coevolutionary arms race should result in the positive selection of particular beneficial alleles. To understand the global role of bracoviruses in the local adaptation or specialization of parasitoid wasps to their hosts, we studied the molecular evolution of four bracoviruses associated with wasps of the genus Cotesia, including C congregata, C vestalis and new data and annotation on two ecologically differentiated populations of C sesamie, Kitale and Mombasa. Paired orthologs analyses revealed more genes under positive selection when comparing the two C sesamiae bracoviruses belonging to the same species, and more genes under strong evolutionary constraint between species. Furthermore branch-site evolutionary models showed that 17 genes, out of the 54 currently available shared by the four bracoviruses, harboured sites under positive selection including: the histone H4-like, a C-type lectin, two ep1-like, ep2, a viral ankyrin, CrV1, a ben-domain, a Serine-rich, and eight unknown genes. Lastly the phylogenetic analyses of the histone, ep2 and CrV1 genes in different African C sesamiae populations showed that each gene described differently the individual relationships. In particular we found recombination had happened between the ep2 and CrV1 genes, which are localized 37.5 kb apart on the wasp chromosomes. Involved in multidirectional coevolutionary interactions, C sesamiae wasps rely on different bracovirus mediated molecular pathways to overcome

Biology and life history of Atanycolus cappaerti (Hymenoptera: Braconidae), a north american larval parasitoid attacking the invasive Emerald Ash Borer (Coleoptera: Buprestidae)

Science.gov (United States)

Atanycolus cappaerti Marsh and Strazanac is a native North American parasitoid that has been found to parasitize the emerald ash borer, Agrilus planipennis Fairmaire, a serious invasive pests of North American ash trees (Fraxinus spp.). To facilitate the development of potential augmentative biocon...

Trade-offs in parasitism efficiency and brood size mediate parasitoid coexistence, with implications for biological control of the invasive emerald ash borer

Science.gov (United States)

Parasitoids often are selected for use as biological control agents because of their high host specificity, yet such host specificity can result in strong interspecific competition. However, few studies have examined if and how various extrinsic factors (such as parasitism efficiency) influence the ...

Residual toxicity of insecticides used in Tunisian citrus orchards on the imported parasitoid Diachasmimorpha longicaudata (Hymenoptera: Braconidae: Implications for IPM program of Ceratitis capitata (Diptera: Tephritidae

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Ahlem Harbi

2017-12-01

Full Text Available Citrus agro-industry is globally harshened mainly by Ceratitis capitata (Wiedemann, the most worldwide destructive tephritid fruit fly species. Citrus agro-industry is one of the pillars of Tunisia economy, and by hence, harshened by this species. Tunisia has established an Integrated Pest Management (IPM programme against citrus pests, including C. capitata, that rely on the structured use of pesticides, on the application several trapping protocols, along with pilot-scale sterile insect technique program and, since 2013, with pilot-scale releases of the braconid parasitoid Diachasmimorpha longicaudata Ashmed (Hymenoptera: Braconidae. Insecticide side-effects on parasitoids and other natural enemies are being requested for a successful implementation of biological control within any IPM programme. However, these data are almost scarce for the braconid species D. longicaudata. To this end, we have determined the side-effects of malathion, methidathion, acetamiprid, azadiractin, abamectin, deltametrin+thiacloprid and spinosad, as the most popular insecticides used in Tunisia either as fresh residues or at several aged time points, on the parasitoid D. longicaudata according the IOBC pesticide harm-classification. IOBC classification evolution of residues over time had allowed determining the best combination of pesticide applications in a structured fashion with the viable releases of D. longicaudata for the control of C. capitata in Tunisian citrus agro-ecosystems.

Residual toxicity of insecticides used in Tunisian citrus orchards on the imported parasitoid Diachasmimorpha longicaudata (Hymenoptera: Braconidae): Implications for IPM program of Ceratitis capitata (Diptera: Tephritidae)

Energy Technology Data Exchange (ETDEWEB)

Harbi, A.; Abbes, K.; Sabater-Muñoz, B.; Beitia, F.; Chermiti, B.

2017-07-01

Citrus agro-industry is globally harshened mainly by Ceratitis capitata (Wiedemann), the most worldwide destructive tephritid fruit fly species. Citrus agro-industry is one of the pillars of Tunisia economy, and by hence, harshened by this species. Tunisia has established an Integrated Pest Management (IPM) programme against citrus pests, including C. capitata, that rely on the structured use of pesticides, on the application several trapping protocols, along with pilot-scale sterile insect technique program and, since 2013, with pilot-scale releases of the braconid parasitoid Diachasmimorpha longicaudata Ashmed (Hymenoptera: Braconidae). Insecticide side-effects on parasitoids and other natural enemies are being requested for a successful implementation of biological control within any IPM programme. However, these data are almost scarce for the braconid species D. longicaudata. To this end, we have determined the side-effects of malathion, methidathion, acetamiprid, azadiractin, abamectin, deltametrin+thiacloprid and spinosad, as the most popular insecticides used in Tunisia either as fresh residues or at several aged time points, on the parasitoid D. longicaudata according the IOBC pesticide harm-classification. IOBC classification evolution of residues over time had allowed determining the best combination of pesticide applications in a structured fashion with the viable releases of D. longicaudata for the control of C. capitata in Tunisian citrus agro-ecosystems.

The cost of assuming the life history of a host: acoustic startle in the parasitoid fly Ormia ochracea.

Science.gov (United States)

Rosen, M J; Levin, E C; Hoy, R R

2009-12-01

In the obligatory reproductive dependence of a parasite on its host, the parasite must trade the benefit of 'outsourcing' functions like reproduction for the risk of assuming hazards associated with the host. In the present study, we report behavioral adaptations of a parasitic fly, Ormia ochracea, that resemble those of its cricket hosts. Ormia females home in on the male cricket's songs and deposit larvae, which burrow into the cricket, feed and emerge to pupate. Because male crickets call at night, gravid female Ormia in search of hosts are subject to bat predation, in much the same way as female crickets are when responding to male song. We show that Ormia has evolved the same evasive behavior as have crickets: an acoustic startle response to bat-like ultrasound that manifests clearly only during flight. Furthermore, like crickets, Ormia has a sharp response boundary between the frequencies of song and bat cries, resembling categorical perception first described in the context of human speech.

Assessing European egg parasitoids as a mean of controlling the invasive South American tomato pinworm Tuta absoluta.

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Anaïs Chailleux

Full Text Available The South American tomato pinworm (Tuta absoluta has recently invaded Europe and is rapidly spreading in the Afro-Eurasian continent where it is becoming a major pest on tomato crops. Laboratory tests were undertaken to evaluate the potential of 29 European strains of Trichogramma parasitoids to control T. absoluta. In addition to the host itself, the host plant (tomato was used during the laboratory tests in order to increase the chance of selecting the best parasitoid strains. Trichogramma females were placed with T. absoluta eggs on a tomato leaflet in tubes. We compared the parasitism of T. absoluta by the various Trichogramma species tested to the Trichogramma species currently commercially available for the pest control in Europe, i.e. Trichogramma achaeae. Thereafter, the more promising strains were tested on a larger scale, in mesocosm (i.e. cages in greenhouses and in greenhouse compartments to evaluate efficiency of laboratory selected strains under cropping conditions. The most efficient strain from the laboratory screening trials did not perform as efficiently under the greenhouse conditions. We discuss differences in parasitism levels among species and strains and among the different scales tested in the experiments, as well as implications of these results for further screening for biocontrol agents.

Acoustic Neuroma Association

Science.gov (United States)

... EVENTS DONATE NEWS Home Learn Back Learn about acoustic neuroma AN Facts What is acoustic neuroma? Diagnosing ... Brain Freeze ? READ MORE Read More What is acoustic neuroma? Identifying an AN Learn More Get Info ...

Biological and Cultural Control of Olive Fruit Fly in California---Utilization of Parasitoids from USDA-APHIS-PPQ, Guatemala and Cultural Control Methods

Science.gov (United States)

The parasitoid Psytallia humilis = P. cf. concolor (Szépligeti) was reared on sterile Mediterranean fruit fly, Ceratitis capitata (Wiedemann), larvae at the USDA, APHIS, PPQ, Moscamed biological control laboratory in San Miguel Petapa, Guatemala and shipped to the USDA, ARS, Parlier, for biological ...

Impact of botanical pesticides derived from Melia azedarach and Azadirachta indica on the biology of two parasitoid species of the diamondback moth

NARCIS (Netherlands)

Charleston, D.S.; Kfir, R.; Dicke, M.; Vet, L.E.M.

2005-01-01

The effect of two botanical pesticides was tested on two species of parasitoids, Cotesia plutellae and Diadromus collaris. Aqueous leaf extracts from the syringa tree, Melia azedarach and commercial formulations from the neem tree, Azadirachta indica, Neemix 4.5 were investigated in the laboratory

Signal transduction downstream of salicylic and jasmonic acid in herbivory-induced parasitoid attraction by Arabidopsis is independent of JAR1 and NPR1

NARCIS (Netherlands)

Poecke, van R.M.P.; Dicke, M.

2003-01-01

Plants can defend themselves indirectly against herbivores by emitting a volatile blend upon herbivory that attracts the natural enemies of these herbivores, either predators or parasitoids. Although signal transduction in plants from herbivory to induced volatile production depends on jasmonic acid

Comparison of the olfactory preferences of four species of filth fly pupal parasitoid species (Hymenoptera: Pteromalidae) for hosts in equine and bovine manure

Science.gov (United States)

House flies (Musca domestica L.) and stable flies (Stomoxys calcitrans (L.)) (Diptera: Muscidae) are common pests in equine and cattle facilities. Pupal parasitoids primarily in the genera Spalangia and Muscidifurax (Hymenoptera: Pteromalidae) can be purchased for biological control of these flies. ...

Development of ion-acoustic double layers through ion-acoustic fluctuations

International Nuclear Information System (INIS)

Sekar, A.N.; Saxena, Y.C.

1985-01-01

Experimental results on the formation of ion acoustic double layers resembling asymmetric ion-holes are presented. In a double plasma device, modified suitably to inject electron beam into the target plasma, modulation of the beam through step potential leads to excitation of ion-acoustic fluctuation. The ion-acoustic fluctuation, growing away from the grids separating source and target plasmas, developed into weak asymmetric ion-acoustic double layer. The observations are in qualitative agreement with theoretical models and computer simulations. (author)

Acoustic tweezers via sub-time-of-flight regime surface acoustic waves.

Science.gov (United States)

Collins, David J; Devendran, Citsabehsan; Ma, Zhichao; Ng, Jia Wei; Neild, Adrian; Ai, Ye

2016-07-01

Micrometer-scale acoustic waves are highly useful for refined optomechanical and acoustofluidic manipulation, where these fields are spatially localized along the transducer aperture but not along the acoustic propagation direction. In the case of acoustic tweezers, such a conventional acoustic standing wave results in particle and cell patterning across the entire width of a microfluidic channel, preventing selective trapping. We demonstrate the use of nanosecond-scale pulsed surface acoustic waves (SAWs) with a pulse period that is less than the time of flight between opposing transducers to generate localized time-averaged patterning regions while using conventional electrode structures. These nodal positions can be readily and arbitrarily positioned in two dimensions and within the patterning region itself through the imposition of pulse delays, frequency modulation, and phase shifts. This straightforward concept adds new spatial dimensions to which acoustic fields can be localized in SAW applications in a manner analogous to optical tweezers, including spatially selective acoustic tweezers and optical waveguides.

Host range and reproductive output of Diachasmimorpha kraussii (Hymenoptera: Braconidae), a parasitoid of tephritid fruit flies newly imported to Hawaii

International Nuclear Information System (INIS)

Messing, R.H.; Ramadan, M.M.

2000-01-01

Four exotic tephritid fruit fly pests have colonised the Hawaiian islands over the past 100 years, where they have become major pests infesting hundreds of horticultural crops. The Mediterranean fruit fly, Ceratitis capitata (Wiedemann), Oriental fruit fly, Bactrocera dorsalis (Hendel), melon fly, B. cucurbitae (Coquillett), and Solanaceous fruit fly, B. latifrons (Hendel) are considered among the major obstacles to the development of a more robust agricultural economy in the state of Hawaii. Furthermore, the flies pose a continuous threat to agriculture in California and other areas in the southern United States, where it has been estimated that the establishment of the Medfly alone would result in losses of over one billion dollars annually (Andrew et al. 1978). Entomologists in Hawaii have conducted a number of classical biological control programmes against these tephritid pests over the years, resulting in the establishment of several parasitoid species and partial control of the flies in some crops (see reviews in Clausen et al. 1965, Wharton 1989). However, these programmes were conducted before the invasion of the state by the Solanaceous fruit fly; thus, there have been no biocontrol programmes targeted against this pest. Also, several entomologists have pointed out the potential of improved control over the other tephritid species in Hawaii by introducing new natural enemies (Gilstrap and Hart 1987, Messing 1995, Steck et al. 1986, Wharton 1989, Wong and Ramadan 1992). We have therefore renewed efforts to import parasitoids from tropical and sub-tropical areas around the world to attack tephritid fruit flies in Hawaii. As part of this effort, we imported Diachasmimorpha kraussii Fullaway from Queensland, Australia, where it is an endemic parasitoid of Bactrocera tryoni (Froggatt) and several other endemic Australian tephritids. This paper reports the results of initial host range tests and studies on the reproductive output of D. kraussii in quarantine

Irradiation of Eggs and Larvae of Bactrocera Carambolae (Drew and Hancock) Fruit Fly to Produce Irradiation Host for Its Parasitoids

International Nuclear Information System (INIS)

Achmad Nasroh Kuswadi; Murni lndarwatmi; Nasution, Indah Arastuti

2004-01-01

Bactrocera carambolae (Drew and Hancock) fruit fly, a major pests of commercial fruits in Indonesia, is attacked by several species of parasitoids in the field, such as by Biosteres sp. that attacks on early instar larvae and Opius sp. on late instar larvae. In order to produce irradiated host in mass rearing of both species, several dosage of gamma were tested on both eggs and larvae. Egg masses of 0.5 ml were irradiated with 0, 10, 20, 30, 40 and 50 Gy and then inoculated into artificial diet. Viability of the eggs, the larval period and the number of pupae produced were observed. About 200 third instar larvae irradiated with 0, 10, 30, 50,70 dan 90 Gy and the number and quality of the pupae developed were then observed. The results showed that the eggs irradiated with tested dosage did not reduce its viability however it reduced the survival of larvae emerged. Number of pupae produced from 0.5 ml irradiated eggs were reduced from 2740 pupae to 407, 167, 113, 53 and 44 pupae, besides the pupation delayed up to three days. Irradiation on third instars larvae did not reduce its pupation, since pupae were developed from > 85 % of irradiated larvae. However, irradiation did reduced the fly emergence from the pupae. Irradiated hosts for Biosteres sp and Opius sp can be produced by irradiating eggs however it should be evaluated since the survival rate of the larvae reduced. Irradiation of third instar larvae may produce irradiated host for Opius sp So, the use of irradiated eggs or irradiated larvae as host in the colonization of the parasitoids will insure no hosts emerged as adult. However it remain to be proved whether irradiated hosts are prefered and able to support the life of parasitoid. (author)

Diaspidídeos e parasitoides associados ao cultivo da videira no Rio Grande do Sul, Brasil

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Vera Regina dos Santos Wolff

2014-12-01

Full Text Available As cochonilhas-com-escudo (Hemiptera, Diaspididae têm causado prejuízos significativos à cultura da videira no Rio Grande do Sul, principalmente em Vitis labrusca L. da cv. Niágara. No período de setembro de 2009 a outubro de 2011, foi realizado um inventário das espécies de Diaspididae ocorrentes no tronco das videiras e dos parasitoides associados. Foram avaliadas 32 propriedades localizadas nos municípios de Bento Gonçalves, Caxias do Sul, Flores da Cunha e Sarandi-RS. A espécie mais frequente e abundante foi Hemiberlesia lataniae (Signoret, 1869. Melanaspis arnaldoi (Costa Lima, 1924 e Pseudaonidia marquesi Costa Lima, 1924 foram registradas pela primeira vez em V. labrusca. Todas as espécies de cochonilhas apresentaram perfurações nos escudos indicando níveis de parasitismo natural que variaram de 11,3 a 76,5% para H. lataniae, de 9 a 58,8% para M. arnaldoi e de 3,4 a 22,2% para P. marquesi. As seguintes associações entre parasitoides e cochonilhas foram encontradas: Encarsia sp. (Aphelinidae, Plagiomerus sp. (Encyrtidae, Amitus sp. (Platygastridae e o hiperparasitoide Chartocerus sp. (Signiphoridae a H. lataniae; Homalopoda sp. (Encyrtidae a P. marquesi e Chartocerus sp. a M. arnaldoi. Amitus sp., Homalopoda sp. e Chartocerus sp. foram associados pela primeira vez com estes diaspidídeos.

Acoustic textiles

CERN Document Server

Nayak, Rajkishore

2016-01-01

This book highlights the manufacturing and applications of acoustic textiles in various industries. It also includes examples from different industries in which acoustic textiles can be used to absorb noise and help reduce the impact of noise at the workplace. Given the importance of noise reduction in the working environment in several industries, the book offers a valuable guide for companies, educators and researchers involved with acoustic materials.

Architectural acoustics

National Research Council Canada - National Science Library

Long, Marshall

2014-01-01

.... Beginning with a brief history, it reviews the fundamentals of acoustics, human perception and reaction to sound, acoustic noise measurements, noise metrics, and environmental noise characterization...

Supersonic acoustic intensity with statistically optimized near-field acoustic holography

DEFF Research Database (Denmark)

Fernandez Grande, Efren; Jacobsen, Finn

2011-01-01

The concept of supersonic acoustic intensity was introduced some years ago for estimating the fraction of the flow of energy radiated by a source that propagates to the far field. It differs from the usual (active) intensity by excluding the near-field energy resulting from evanescent waves...... to the information provided by the near-field acoustic holography technique. This study proposes a version of the supersonic acoustic intensity applied to statistically optimized near-field acoustic holography (SONAH). The theory, numerical results and an experimental study are presented. The possibility of using...

Structure and composition of the assemblage of parasitoids associated to Phyllocnistis citrella pupae Stainton (Lepidoptera: Gracillariidae) in citrus orchards in Southern Brazil

International Nuclear Information System (INIS)

Jahnke, Simone M.; Redaelli, Luiza R.; Soglio, Fabio K. Dal

2007-01-01

The structure and composition of the assemblage of pupal parasitoids of Phyllocnistis citrella Stainton, the citrus leaf miner, were studied in two citrus orchards (Citrus deliciosa Tenore cv. Montenegrina and Citrus sinensis (L.) Osbeck x Citrus reticulata Blanco hybrid Murcott), in Montenegro County (29 deg 68S and 51 deg 46W), southern Brazil. At fortnightly samplings, from July 2001 to June 2003, all the new shoots from 24 randomly selected trees were inspected. The species richness reached five native species in the Murcott orchard, and six in Montenegrina. In Murcott, the presence of Ageniaspis citricola (Hymenoptera: Encyrtidae), an exotic species, was detected in the first year of sampling, probably migrating from the nearby areas where it had been released for the miner control. In Montenegrina, its presence was only registered in the second year. A. citricola in both areas was dominant and changed the community structure of parasitoid complex of P. citrella in both orchards. (author)

Acoustic Metamaterials in Aeronautics

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Giorgio Palma

2018-06-01

Full Text Available Metamaterials, man-made composites that are scaled smaller than the wavelength, have demonstrated a huge potential for application in acoustics, allowing the production of sub-wavelength acoustic absorbers, acoustic invisibility, perfect acoustic mirrors and acoustic lenses for hyper focusing, and acoustic illusions and enabling new degrees of freedom in the control of the acoustic field. The zero, or even negative, refractive sound index of metamaterials offers possibilities for the control of acoustic patterns and sound at sub-wavelength scales. Despite the tremendous growth in research on acoustic metamaterials during the last decade, the potential of metamaterial-based technologies in aeronautics has still not been fully explored, and its utilization is still in its infancy. Thus, the principal concepts mentioned above could very well provide a means to develop devices that allow the mitigation of the impact of civil aviation noise on the community. This paper gives a review of the most relevant works on acoustic metamaterials, analyzing them for their potential applicability in aeronautics, and, in this process, identifying possible implementation areas and interesting metabehaviors. It also identifies some technical challenges and possible future directions for research with the goal of unveiling the potential of metamaterials technology in aeronautics.

Calibration of acoustic emission transducers

International Nuclear Information System (INIS)

Leschek, W.C.

1976-01-01

A method is described for calibrating an acoustic emission transducer to be used in a pre-set frequency range. The absolute reception sensitivity of a reference transducer is determined at frequencies selected within the frequency range. The reference transducer and the acoustic emission transducer are put into acoustic communication with the surface of a limited acoustic medium representing an equivalent acoustic load appreciably identical to that of the medium in which the use of the acoustic emission transducer is intended. A blank random acoustic noise is emitted in the acoustic medium in order to establish a diffuse and reverberating sound field, after which the output responses of the reference transducer and of the acoustic emission transducer are obtained with respect to the diffuse and reverberating field, for selected frequencies. The output response of the acoustic emission transducer is compared with that of the reference transducer for the selected frequencies, so as to determine the reception sensitivity of the acoustic emission transducer [fr

Biological aspects of Cirrospilus neotropicus Diez and Fidalgo (Hymenoptera: Eulophidae), parasitoid of Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae); Aspectos biologicos de Cirrospilus neotropicus Diez e Fidalgo (Hymenoptera: Eulophidae), parasitoide de Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae)

Energy Technology Data Exchange (ETDEWEB)

Foelkel, Ester [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Programa de Pos-Graduacao em Fitotecnia; Redaelli, Luiza R.; Jahnke, Simone M.; Losekann, Paula B. [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Dept. de Fitossanidade

2008-05-15

The biology of Cirrospilus neotropicus Diez and Fidalgo reared on third instar Phyllocnistis citrella Stainton larvae having Citrus limonia Osbeck as host plant, was evaluated under controlled conditions (25 {+-} 1 deg C; 12 h photophase). The survival, immature development, longevity, sex ratio, host feeding and oviposition ratio of C. neotropicus, were registered. Two groups of parasitoid females were evaluated: one, with parasitoids obtained from P. citrella pupae collected in citrus orchards and the other group came from laboratory rearing. These females, after mating, were maintained individually on gerbox containers with honey and pollen as food source. At each 48h, 12 P. citrella larvae were changed. The average biological cycle of the female progenies from orchard and laboratory generation groups were 11.8 and 11.6 days, respectively. The males progenies had biological cycles of 11.6 and 10.9 days, as well. The shortest immature survival period, for both studied groups was the larval (57.3% - orchard group and 57.4% - lab group). The mated females average longevity (21.8 days) was superior than the non mated ones (9.1 days) for the orchard group. The average daily oviposition rate for this last group was also significantly superior (2.8 eggs /day) than the lab group (1.6 eggs / day). The same trend was observed for the average daily host feeding rate (1.7 larvae /day for the orchard group and 0.9 larvae/ day for the lab group). These data suggest that C. neotropicus have potential as a biological control agent of P. citrella. (author)

Regional tritrophic relationship patterns of five aphid parasitoid species (Hymenoptera: Braconidae: Aphidiinae)in agroecosystem-dominated landscapes of southeastern Europe

Czech Academy of Sciences Publication Activity Database

Tomanović, Ž.; Kavallieratos, N. G.; Starý, Petr; Stanisavljević, L. Ž.; Ćetković, A.; Stamenković, S.; Jovanović, S.; Athanassiou, CH. G.

2009-01-01

Roč. 102, č. 3 (2009), s. 836-854 ISSN 0022-0493 R&D Projects: GA AV ČR IBS5007102 Grant - others:The Ministry of Science and Environmental Protection of the Republic of Serbia(CS) 143006B Institutional research plan: CEZ:AV0Z50070508 Keywords : aphid parasitoids * southeastern Europe * tritropic interactions Subject RIV: EH - Ecology, Behaviour Impact factor: 1.296, year: 2009

Oogenesis pattern and type of ovariole of the parasitoid Palmistichus elaeisis (Hymenoptera: Eulophidae

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Gilberto S. Andrade

2012-09-01

Full Text Available The knowledge on ovigeny in parasitoids is important for basic studies on physiology and applied biological control. The ovigeny pattern and type of ovariole of the parasitoid Palmistichus elaeisis Delvare & LaSalle (Hymenoptera: Eulophidae were studied in newly-emerged females at seven, 14, 24 and 48 h intervals after their emergence from Tenebrio molitor L. pupae (Coleoptera: Tenebrionidae. Females of P. elaeisis presented ovaries composed by four ovarioles of the meroistic polytrophic type. The yolk accumulation and chorionogenesis in P. elaeisis were concluded 24 h after the female emergence. The 48 h-old females show a high quantity of egg ready for oviposition. These findings can help to improve the mass production of P. elaeisis and the augmentative biological control by using this natural enemy.O conhecimento da ovigenia em parasitóides é importante para estudos básicos em fisiologia e para o controle biológico aplicado. O padrão de ovigenia e OVIGENY OF Palmistichus elaeisis (HYMENOPTERA: EULOPHIDAE o tipo de ovaríolo do parasitóide Palmistichus elaeisis Delvare & LaSalle (Hymenopera: Eulophidae foram estudados em fêmeas recém-emergidas e em intervalos de sete, 14, 24 de 48 horas após a emergência em pupas de Tenebrio molitor L. (Coleoptera: Tenebrionidae. Fêmeas de P. elaesis apresentaram o ovário composto por quatro ovaríolos do tipo meroístico politrófico. A deposição de vitelo e corionogênese em P. elaeisis foram concluídas 24 horas após a emergência. Fêmeas com 48 horas de idade apresentam grande quantidade de ovos prontos para a oviposição. Esses resultados podem ajudar a melhoria da produção massal de P. elaeisis e o controle biológico aplicado com esse parasitóide.

Acoustical and optical radiation pressure and the development of single beam acoustical tweezers

International Nuclear Information System (INIS)

Thomas, Jean-Louis; Marchiano, Régis; Baresch, Diego

2017-01-01

Studies on radiation pressure in acoustics and optics have enriched one another and have a long common history. Acoustic radiation pressure is used for metrology, levitation, particle trapping and actuation. However, the dexterity and selectivity of single-beam optical tweezers are still to be matched with acoustical devices. Optical tweezers can trap, move and position micron size particles, biological samples or even atoms with subnanometer accuracy in three dimensions. One limitation of optical tweezers is the weak force that can be applied without thermal damage due to optical absorption. Acoustical tweezers overcome this limitation since the radiation pressure scales as the field intensity divided by the speed of propagation of the wave. However, the feasibility of single beam acoustical tweezers was demonstrated only recently. In this paper, we propose a historical review of the strong similarities but also the specificities of acoustical and optical radiation pressures, from the expression of the force to the development of single-beam acoustical tweezers. - Highlights: • Studies on radiation pressure in acoustics and optics have enriched one another and have a long common history. • Acoustic radiation pressure is used for metrology, levitation, particle trapping and actuation. • However, the dexterity and selectivity of single-beam optical tweezers are still to be matched with acoustical devices. • Optical tweezers can trap, move and positioned micron size particles with subnanometer accuracy in three dimensions. • One limitation of optical tweezers is the weak force that can be applied without thermal damage due to optical absorption. • Acoustical tweezers overcome this limitation since the force scales as the field intensity divided by its propagation speed. • However, the feasibility of single beam acoustical tweezers was demonstrated only recently. • We propose a review of the strong similarities but also the specificities of acoustical

Biochemical characterization and comparison of aspartylglucosaminidases secreted in venom of the parasitoid wasps Asobara tabida and Leptopilina heterotoma.

Directory of Open Access Journals (Sweden)

Quentin Coulette

Full Text Available Aspartylglucosaminidase (AGA is a low-abundance intracellular enzyme that plays a key role in the last stage of glycoproteins degradation, and whose deficiency leads to human aspartylglucosaminuria, a lysosomal storage disease. Surprisingly, high amounts of AGA-like proteins are secreted in the venom of two phylogenetically distant hymenopteran parasitoid wasp species, Asobara tabida (Braconidae and Leptopilina heterotoma (Cynipidae. These venom AGAs have a similar domain organization as mammalian AGAs. They share with them key residues for autocatalysis and activity, and the mature α- and β-subunits also form an (αβ2 structure in solution. Interestingly, only one of these AGAs subunits (α for AtAGA and β for LhAGA is glycosylated instead of the two subunits for lysosomal human AGA (hAGA, and these glycosylations are partially resistant to PGNase F treatment. The two venom AGAs are secreted as fully activated enzymes, they have a similar aspartylglucosaminidase activity and are both also efficient asparaginases. Once AGAs are injected into the larvae of the Drosophila melanogaster host, the asparaginase activity may play a role in modulating their physiology. Altogether, our data provide new elements for a better understanding of the secretion and the role of venom AGAs as virulence factors in the parasitoid wasps' success.

Eugeniamyia dispar em pitangueira: parasitoides associados, dinâmica populacional e distribuição de galhas na planta

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Adriana Neutzling Bierhals

2012-03-01

Full Text Available A pitangueira Eugenia uniflora L. (Myrtaceae é uma frutífera nativa da América do Sul, podendo ser encontrada em quase todo o território brasileiro, bem como no Paraguai, no Uruguai e na Argentina. Nas folhas dessa planta, são encontradas galhas induzidas por Eugeniamyia dispar (Diptera: Cecidomyiidae. O objetivo deste trabalho foi determinar os parasitoides associados a E. dispar, a dinâmica populacional de E. dispar e dos parasitoides e a distribuição de galhas na planta. Ramos e folhas foram coletados quinzenalmente, durante as safras agrícolas de 2007/2008 e 2008/2009, em pomares de pitangueira localizados no município de Pelotas-RS, e transportados para o laboratório para a contagem do número de galhas. Do material coletado, foram individualizadas dez folhas em recipientes plásticos (200 mL contendo 30 mL de uma solução à base de ágar-água (2% e metilpara-hidroxibenzoato (nipagin (0,2%. Os recipientes foram fechados e mantidos sob condições controladas de temperatura (24±2ºC, umidade relativa (70±10% e fotofase (14h, sendo registrado, diariamente, o número de insetos emergidos. Obteve-se uma espécie de Hymenoptera, Rileya hegeli (Eurytomidae, como parasitoide de E. dispar. Quanto à dinâmica populacional de E. dispar e de R. hegeli, foi observado, nos dois anos de avaliação, que a população de ambos aumentou a partir de outubro, atingindo as maiores populações nos meses de dezembro, janeiro e fevereiro, decrescendo posteriormente. O número de galhas por folha variou de zero a 23, sendo que 61,19% das folhas apresentavam de uma a oito galhas e que o número de folhas com galhas por ramo variou de uma a nove, sendo que 63,00% dos ramos apresentaram de uma a três folhas infestadas.

Parasitoids of Diptera collected in traps of different colors from Southern of Goias State / Parasitóides de Diptera coletados em armadilhas de diferentes cores no Sul do estado de Goiás

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Gefferson José Silva

2009-07-01

Full Text Available The objective of this study was to report parasitoids of Diptera collected in traps of different colors in the south of Goias state. Twelve traps two as of each color were used, painted yellow, black, red, white, green and blue were used two as of each color. The pupae were obtained by the flotation method. They were individually placed in gelatin capsules until the emergency of the adult flies or their parasitoids. Between March and December 2006, 17 parasitoid specimens were collected from the yellow trap, 15 from the blue trap, 12 from the white trap, 37 from the black trap, one from the green trap and three from the red trap. The parasitoids did not present any preference for any of the trap colors (F=0.772; P=0.58. The most frequently collected parasitoid species was Brachymeria podagrica (Fabricius, 1789 (Hymenoptera: Chalcididae, with 80.0%.O objetivo desse estudo foi descrever os parasitóides de Diptera coletados em armadilhas de diferentes cores no sul do estado de Goiás. Foram utilizadas 12 armadilhas duas de cada tipo pintadas de amarelo preto, vermelho, branco, verde e azul. As pupas dos dípteros foram isoladas pelo método de flutuação, individualizadas em cápsulas de gelatina até a emergência dos parasitóides. Foram coletados no período de março a dezembro de 2006, 17 exemplares de parasitóides na armadilha amarela, 15 na armadilha azul, 12 na armadilha branca, 37 na armadilha preta, um exemplar na armadilha verde e três na armadilha vermelha. Os parasitóides não apresentaram atração por nenhuma das cores das armadilhas (F= 0,772; P=0,58. A espécie de parasitóide mais freqüente foi Brachymeria podagrica (Fabricius, 1789 (Hymenoptera: Chalcididae com 80,0%.

Evaluating a new method for monitoring the field establishment and parasitism of Oobius agrili, an egg parasitoid of the emerald ash borer

Science.gov (United States)

Oobius agrili is a solitary egg parasitoid of emerald ash borer (EAB), Agrilus planipennis, and can be responsible for 50-60% of EAB egg mortality in its native range. O. agrili has been released for biological control of EAB in the US since 2007; however, current methods to monitor its establishme...

Radiation acoustics and its applications

International Nuclear Information System (INIS)

Lyamshev, L.M.

1992-01-01

Radiation acoustics is a new branch of acoustics, developing on the boundary of acoustics, nuclear physics, elementary particles and high-energy physics. Its fundamentals are laying in the research of acoustical effects due to the interaction of penetrating radiation with matter. The study of radiation-acoustical effects leads to the new opportunities in the penetration radiation research (acoustical detection, radiation-acoustical dosimetry), study of the physical parameters of matter, in a solution of some applied problems of nondestructive testing, and also for the radiation-acoustical influence on physical and chemical structure of the matter. Results of theoretical and experimental investigations are given. Different mechanisms of the sound generation by penetrating radiation of liquids and solids are considered. Some applications - the radiation acoustical microscopy and visualisation, the acoustical detection of high energy X-ray particles and possibility of using of high energy neutrino beams in geoacoustics - are discussed

Parametric Room Acoustic Workflows

DEFF Research Database (Denmark)

Parigi, Dario; Svidt, Kjeld; Molin, Erik

2017-01-01

The paper investigates and assesses different room acoustics software and the opportunities they offer to engage in parametric acoustics workflow and to influence architectural designs. The first step consists in the testing and benchmarking of different tools on the basis of accuracy, speed...... and interoperability with Grasshopper 3d. The focus will be placed to the benchmarking of three different acoustic analysis tools based on raytracing. To compare the accuracy and speed of the acoustic evaluation across different tools, a homogeneous set of acoustic parameters is chosen. The room acoustics parameters...... included in the set are reverberation time (EDT, RT30), clarity (C50), loudness (G), and definition (D50). Scenarios are discussed for determining at different design stages the most suitable acoustic tool. Those scenarios are characterized, by the use of less accurate but fast evaluation tools to be used...

Producción masiva automatizada de la broca del café Hypothenemus hampei Ferrari (Coleóptera: Scolytidae) y de sus parasitoides sobre dietas artificiales

Science.gov (United States)

This article reviews the current state of knowledge concerning the mass rearing system of the coffee berry borer, cbb, Hypothenemus hampei (Ferrari) (Coleoptera: Scolytidae), and its African parasitoids: the ectoparasitoids Cephalonomia stephanoderis (Betrem) and Prorops nasuta ((Waterston) (Hymenop...

Effects of Banana Plantation Pesticides on the Immune Response of Lepidopteran Larvae and Their Parasitoid Natural Enemies

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Angela M. Smilanich

2012-06-01

Full Text Available Basic research on the insect immune response has progressed dramatically within the last two decades, showing that immunity is one of the most effective defenses against foreign invaders. As such, it is important to understand the causes of variation in this response. Here, we investigate the effects of pesticides used in Costa Rican banana plantations on the immune response of the lepidopteran larva, Caligo memnon (Brassolinae. In addition, we performed a parasitism survey of the banana plantations and surrounding forests to provide a broader assessment of pesticide effects on parasitoid populations. All caterpillars for the immune assay were collected from two banana plantations and brought to La Selva Biology Station for immune challenge. Individuals were fed leaves from the plantations (pesticide or leaves from La Selva (pesticide-free, then immune challenged with injected sephadex beads. We found that individuals feeding on pesticide leaves had significantly lower bead melanization compared to individuals feeding on pesticide-free leaves. Nonetheless, the parasitism survey showed that caterpillars from the banana plantations had lower parasitism rates compared to caterpillars from the La Selva forest. This study adds to the growing body of evidence documenting negative effects of pesticides on the insect immune response and on adult parasitoids, and underscores the need for more research at the intersection between ecological entomology and immunology.

Acoustic Neuroma

Science.gov (United States)

An acoustic neuroma is a benign tumor that develops on the nerve that connects the ear to the brain. ... can press against the brain, becoming life-threatening. Acoustic neuroma can be difficult to diagnose, because the ...

High-Frequency Seafloor Acoustics

CERN Document Server

Jackson, Darrell R

2007-01-01

High-Frequency Seafloor Acoustics is the first book in a new series sponsored by the Office of Naval Research on the latest research in underwater acoustics. This exciting new title provides ready access to experimental data, theory, and models relevant to high-frequency seafloor acoustics and will be of interest to sonar engineers and researchers working in underwater acoustics. The physical characteristics of the seafloor affecting acoustic propagation and scattering are covered, including physical and geoacoustic properties and surface roughness. Current theories for acoustic propagation in sediments are presented along with corresponding models for reflection, scattering, and seafloor penetration. The main text is backed up by an extensive bibliography and technical appendices.

Assessing risks of pesticides targeting lepidopteran pests in cruciferous ecosystems to eggs parasitoid, Trichogramma brassicae (Bezdenko

Directory of Open Access Journals (Sweden)

D.P. Thubru

2018-05-01

Full Text Available Lethal and sub lethal effects of fresh and old residues of azadirachtin, spinosad, Bacillus thuringiensis var. kurstaki (Bt var. k, and deltamethrin, were evaluated at their recommended field doses against adult and immature stages of Trichogramma brassicae under in vitro conditions. The experiments were carried out at the Entomology section of Division of Crop Protection, ICAR Research Complex for NEH region, Umiam, Meghalaya, in 2012–2013. The effects of different pesticides were determined by bioassays using the residual film method, the diet contamination method, the pupal dip method and the topical application technique. The four pesticides were found harmful to adult T. brassicae after ingestion, however surface contact bioassays revealed that Bt var. k was the least toxic pesticide. Except Bt var. k, other three pesticides were found harmful also to the immature stages of T. brassicae and significantly affected parasitism potential, adult emergence, longevity of adults, and sex ratio of the progeny. Deltamethrin and azadirachtin were the most harmful, even after 15 days of application. Spinosad was found to be relatively safe to T. brassicae after 15 days of application. As Bt appeared to be the least toxic pesticide for T. brassicae, it could be used for the management of severe infestations of lepidopteran pests in cruciferous ecosystems.If essential, spinosad may be used 15 days after parasitoid release, thus minimizing the chances of parasitoid exposure. Keywords: Azadirachtin, Bacillus thuringiensis, Deltamethrin, Spinosad

Acoustic evaluation of wood quality in standing trees. Part I, Acoustic wave behavior

Science.gov (United States)

Xiping Wang; Robert J. Ross; Peter Carter

2007-01-01

Acoustic wave velocities in standing trees or live softwood species were measured by the time-of-flight (TOF) method. Tree velocities were compared with acoustic velocities measured in corresponding butt logs through a resonance acoustic method. The experimental data showed a skewed relationship between tree and log acoustic measurements. For most trees tested,...

From Fossil Parasitoids to Vectors: Insects as Parasites and Hosts.

Science.gov (United States)

Nagler, Christina; Haug, Joachim T

2015-01-01

Within Metazoa, it has been proposed that as many as two-thirds of all species are parasitic. This propensity towards parasitism is also reflected within insects, where several lineages independently evolved a parasitic lifestyle. Parasitic behaviour ranges from parasitic habits in the strict sense, but also includes parasitoid, phoretic or kleptoparasitic behaviour. Numerous insects are also the host for other parasitic insects or metazoans. Insects can also serve as vectors for numerous metazoan, protistan, bacterial and viral diseases. The fossil record can report this behaviour with direct (parasite associated with its host) or indirect evidence (insect with parasitic larva, isolated parasitic insect, pathological changes of host). The high abundance of parasitism in the fossil record of insects can reveal important aspects of parasitic lifestyles in various evolutionary lineages. For a comprehensive view on fossil parasitic insects, we discuss here different aspects, including phylogenetic systematics, functional morphology and a direct comparison of fossil and extant species. Copyright © 2015 Elsevier Ltd. All rights reserved.

Room Acoustics

Science.gov (United States)

Kuttruff, Heinrich; Mommertz, Eckard

The traditional task of room acoustics is to create or formulate conditions which ensure the best possible propagation of sound in a room from a sound source to a listener. Thus, objects of room acoustics are in particular assembly halls of all kinds, such as auditoria and lecture halls, conference rooms, theaters, concert halls or churches. Already at this point, it has to be pointed out that these conditions essentially depend on the question if speech or music should be transmitted; in the first case, the criterion for transmission quality is good speech intelligibility, in the other case, however, the success of room-acoustical efforts depends on other factors that cannot be quantified that easily, not least it also depends on the hearing habits of the listeners. In any case, absolutely "good acoustics" of a room do not exist.

Acoustic scaling: A re-evaluation of the acoustic model of Manchester Studio 7

Science.gov (United States)

Walker, R.

1984-12-01

The reasons for the reconstruction and re-evaluation of the acoustic scale mode of a large music studio are discussed. The design and construction of the model using mechanical and structural considerations rather than purely acoustic absorption criteria is described and the results obtained are given. The results confirm that structural elements within the studio gave rise to unexpected and unwanted low-frequency acoustic absorption. The results also show that at least for the relatively well understood mechanisms of sound energy absorption physical modelling of the structural and internal components gives an acoustically accurate scale model, within the usual tolerances of acoustic design. The poor reliability of measurements of acoustic absorption coefficients, is well illustrated. The conclusion is reached that such acoustic scale modelling is a valid and, for large scale projects, financially justifiable technique for predicting fundamental acoustic effects. It is not appropriate for the prediction of fine details because such small details are unlikely to be reproduced exactly at a different size without extensive measurements of the material's performance at both scales.

Plutella xylostella (diamondback moth) and its parasitoid Diadegma semiclausum show different gustatory and longevity responses to a range of nectar and honeydew sugars

NARCIS (Netherlands)

Winkler, K.; Wäckers, F.L.; Stingli, A.; Van Lenteren, J.C.

2005-01-01

Parasitoids as well as many of their herbivorous hosts, depend on carbohydrate-rich food during the adult stage. Different types of nectar and honeydew vary with regard to their sugar composition. In order to successfully exploit a food source, the insect must show a positive gustatory response to

CALCULATION OF ACOUSTIC EFFICIENCY OF PORTABLE ACOUSTIC SCREEN

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Aleksandr Skvortsov

2016-03-01

Full Text Available The research of influence of life environment adverse factors on physical development and health of population is an actual problem of ecology. The aspects of the most actual problems of the modern world, namely environmental industrial noise pollution are considered in the article. Industrial facilities everywhere have noisy equipment. Noise is a significant factors of negative influenceon people and environment. Combined effects of noise and of other physical pollutions on people may cause amplification of their negative impact. If the noise pollution level from the object in a residential area exceeds the permissible levels (MPL, noise protection measures can be initiated. Today, the most common design decisions for noise protection are sound absorbing construction, noise screens and barriers, acousting housings, soundproff cabins. Many of them are popular, others are less known. The article deals with one of the most wide spread means of noise protection – a portable acoustic screen. The aim of the research is to determine the efficiency of portable acoustic screens. It is shown that the installation of such structures can reduce the average value of the sound level. The authors analyzed acoustic screens as device to reduce noise pollution. The authors offer a potable acoustic screen differing from the used easyness, mobility, minimum price and good sound protective properties. Effectiveness, a sound absorption coefficient and sound conductivity coefficient of a portable acoustic screen are evaluated. The descriptions of the algorithm calculations and the combination of technical solutions have practical originality. The results of the research demonstrate the advantages of the proposed solutions for reducing noise levels in the agro-industrial complex.

Effects of subsampling of passive acoustic recordings on acoustic metrics.

Science.gov (United States)

Thomisch, Karolin; Boebel, Olaf; Zitterbart, Daniel P; Samaran, Flore; Van Parijs, Sofie; Van Opzeeland, Ilse

2015-07-01

Passive acoustic monitoring is an important tool in marine mammal studies. However, logistics and finances frequently constrain the number and servicing schedules of acoustic recorders, requiring a trade-off between deployment periods and sampling continuity, i.e., the implementation of a subsampling scheme. Optimizing such schemes to each project's specific research questions is desirable. This study investigates the impact of subsampling on the accuracy of two common metrics, acoustic presence and call rate, for different vocalization patterns (regimes) of baleen whales: (1) variable vocal activity, (2) vocalizations organized in song bouts, and (3) vocal activity with diel patterns. To this end, above metrics are compared for continuous and subsampled data subject to different sampling strategies, covering duty cycles between 50% and 2%. The results show that a reduction of the duty cycle impacts negatively on the accuracy of both acoustic presence and call rate estimates. For a given duty cycle, frequent short listening periods improve accuracy of daily acoustic presence estimates over few long listening periods. Overall, subsampling effects are most pronounced for low and/or temporally clustered vocal activity. These findings illustrate the importance of informed decisions when applying subsampling strategies to passive acoustic recordings or analyses for a given target species.

The use of F1 sterility and parasitoids for population suppression of lepidopteran pests of crucifers in Indonesia

International Nuclear Information System (INIS)

Singgih Sutrisno Apu

2002-01-01

We report on the population suppression of diamondback moth (DBM) Plutella xylostella (L.) (Lepidoptera: Plutellidae) and cabbage webworm (CWW) Crocidolomia binotalis Z. (Lepidoptera: Pyralidae) using releases of irradiated (200 Gy) substerile moths. The impact of substerile DBM was studied in field-cages and moths were released at a 9:1 treated:untreated ratio. Our results show that releasing F 1 substerile male and female DBM resulted in a high level of sterility (73.03% and 73.30% in the F 1 and F 2 generations, respectively) in the untreated population, while the release of only F 1 males induced a lower level of sterility (55.40% and 56.44% in the F 1 and F 2 generations, respectively). When substerile moths were released once per generation, the level of sterility was 44.78% in the F 1 and 68.01% in the F 2 generations. The effect of releasing substerile males only, females only, and substerile male and female CWW on the untreated population were studied in the laboratory. Percent egg hatch was 22.17% for male only releases. For female and mixed sex releases these percentages were 28.50% and 24.75%, respectively. For DBM, some studies combined releases of substerile DBM with releases of the parasitoid Diadegma semiclausum (H) (Hymenoptera: Ichneumonidae) in field-plots. Pupal viability in the F 1 generation in the area that received both parasitoids and substerile DBM was 32.5%. The effect on pupal viability when only a single tactic was used was lower than when both tactics were combined. The release of substerile males only gave a pupal viability of 57.5% and releases of the parasitoid D. semiclausum resulted in 81% pupal viability. When substerile DBM were released into a small isolated forested area in Malang, East Java, the average number of moths caught per week at the release area from June to October 1996 was about 89.42% of that found in the untreated control area. When population fluctuations of wild DBM were followed for 12 months, the lowest

Anti-sound and Acoustical Cloaks

Directory of Open Access Journals (Sweden)

Veturia CHIROIU

2016-12-01

Full Text Available The principles by which the acoustics can be mimicked in order to reduce or cancel the vibrational field are based on anti-sound concept which can be materialized by acoustic cloaks. Geometric transformations open an elegant way towards the unconstrained control of sound through acoustic metamaterials. Acoustic cloaks can be achieved through geometric transformations which bring exotic metamaterial properties into the acoustic equations. Our paper brings new ideas concerning the technological keys for manufacturing of novel metamaterials based on the spatial compression of Cantor structures, and the architecture of 3D acoustic cloaks in a given frequency band, with application to architectural acoustics.

Acoustical and optical radiation pressure and the development of single beam acoustical tweezers

Science.gov (United States)

Thomas, Jean-Louis; Marchiano, Régis; Baresch, Diego

2017-07-01

Studies on radiation pressure in acoustics and optics have enriched one another and have a long common history. Acoustic radiation pressure is used for metrology, levitation, particle trapping and actuation. However, the dexterity and selectivity of single-beam optical tweezers are still to be matched with acoustical devices. Optical tweezers can trap, move and position micron size particles, biological samples or even atoms with subnanometer accuracy in three dimensions. One limitation of optical tweezers is the weak force that can be applied without thermal damage due to optical absorption. Acoustical tweezers overcome this limitation since the radiation pressure scales as the field intensity divided by the speed of propagation of the wave. However, the feasibility of single beam acoustical tweezers was demonstrated only recently. In this paper, we propose a historical review of the strong similarities but also the specificities of acoustical and optical radiation pressures, from the expression of the force to the development of single-beam acoustical tweezers.

Acoustic transparency and slow sound using detuned acoustic resonators

DEFF Research Database (Denmark)

Santillan, Arturo Orozco; Bozhevolnyi, Sergey I.

2011-01-01

We demonstrate that the phenomenon of acoustic transparency and slowsound propagation can be realized with detuned acoustic resonators (DAR), mimicking thereby the effect of electromagnetically induced transparency (EIT) in atomic physics. Sound propagation in a pipe with a series of side...

Computational Ocean Acoustics

CERN Document Server

Jensen, Finn B; Porter, Michael B; Schmidt, Henrik

2011-01-01

Since the mid-1970s, the computer has played an increasingly pivotal role in the field of ocean acoustics. Faster and less expensive than actual ocean experiments, and capable of accommodating the full complexity of the acoustic problem, numerical models are now standard research tools in ocean laboratories. The progress made in computational ocean acoustics over the last thirty years is summed up in this authoritative and innovatively illustrated new text. Written by some of the field's pioneers, all Fellows of the Acoustical Society of America, Computational Ocean Acoustics presents the latest numerical techniques for solving the wave equation in heterogeneous fluid–solid media. The authors discuss various computational schemes in detail, emphasizing the importance of theoretical foundations that lead directly to numerical implementations for real ocean environments. To further clarify the presentation, the fundamental propagation features of the techniques are illustrated in color. Computational Ocean A...

Acoustic Test Results of Melamine Foam with Application to Payload Fairing Acoustic Attenuation Systems

Science.gov (United States)

Hughes, William O.; McNelis, Anne M.

2014-01-01

A spacecraft at launch is subjected to a harsh acoustic and vibration environment resulting from the passage of acoustic energy, created during the liftoff of a launch vehicle, through the vehicle's payload fairing. In order to ensure the mission success of the spacecraft it is often necessary to reduce the resulting internal acoustic sound pressure levels through the usage of acoustic attenuation systems. Melamine foam, lining the interior walls of the payload fairing, is often utilized as the main component of such a system. In order to better understand the acoustic properties of melamine foam, with the goal of developing improved acoustic attenuation systems, NASA has recently performed panel level testing on numerous configurations of melamine foam acoustic treatments at the Riverbank Acoustical Laboratory. Parameters assessed included the foam's thickness and density, as well as the effects of a top outer cover sheet material and mass barriers embedded within the foam. This testing followed the ASTM C423 standard for absorption and the ASTM E90 standard for transmission loss. The acoustic test data obtained and subsequent conclusions are the subjects of this paper.

New records of fruit flies (Diptera: Tephritidae), wild hosts and parasitoids (Hymenoptera: Braconidae) in the Brazilian Amazon

Energy Technology Data Exchange (ETDEWEB)

Jesus, Cristiane R. de; Oliveira, Manoela N. de; Silva, Ricardo A. da [EMBRAPA Amapa, Macapa, AP (Brazil); Pereira, Julia D.B. [Universidade Federal do Amapa, Macapa, AP (Brazil); Souza Filho, Miguel F. [Instituto Biologico, Campinas, SP (Brazil); Costa Neto, Salustiano V. da [Instituto de Pesquisas Cientificas e Tecnologicas do Amapa, Macapa, AP (Brazil); Marinho, Claudia F.; Zucchi, Roberto A. [Escola Superior de Agricultura Luiz de Queiroz (ESALQ/USP), Piracicaba, SP (Brazil). Dept. de Entomologia, Fitopatologia e Zoologia Agricola

2008-11-15

Anastrepha anomala Stone was obtained from Parahancornia amapa (Huber) Ducke (Apocynaceae) fruits, and Anastrepha hastata Stone from Cheiloclinium cognatum (Miers.) (Hippocrateaceae) in the State of Amapa, Brazil. Two braconids, Doryctobracon sp. and Opius bellus Gahan, were reared from the latter fruit fl y species. This is the fi rst record of P. amapa as a fruit fl y host. C. cognatum is the fi rst host known to A. hastata. Both braconids are also the fi rst records of parasitoids for this species. (author)

Density-near-zero using the acoustically induced transparency of a Fano acoustic resonator

KAUST Repository

Elayouch, A.

2017-01-05

We report experimental results of near-zero mass density involving an acoustic metamaterial supporting Fano resonance. For this, we designed and fabricated an acoustic resonator with two closely coupled modes and measured its transmission properties. Our study reveals that the phenomenon of acoustically induced transparency is accompanied by an effect of near-zero density. Indeed, the dynamic effective parameters obtained from experimental data show the presence of a frequency band where the effective mass density is close to zero, with high transmission levels reaching 0.7. Furthermore, we demonstrate that such effective parameters lead to wave guiding in a 90-degrees-bent channel. This kind of acoustic metamaterial can, therefore, give rise to acoustic functions like controlling the wavefront, which may lead to very promising applications in acoustic cloacking or imaging.

Introducing passive acoustic filter in acoustic based condition monitoring: Motor bike piston-bore fault identification

Science.gov (United States)

Jena, D. P.; Panigrahi, S. N.

2016-03-01

Requirement of designing a sophisticated digital band-pass filter in acoustic based condition monitoring has been eliminated by introducing a passive acoustic filter in the present work. So far, no one has attempted to explore the possibility of implementing passive acoustic filters in acoustic based condition monitoring as a pre-conditioner. In order to enhance the acoustic based condition monitoring, a passive acoustic band-pass filter has been designed and deployed. Towards achieving an efficient band-pass acoustic filter, a generalized design methodology has been proposed to design and optimize the desired acoustic filter using multiple filter components in series. An appropriate objective function has been identified for genetic algorithm (GA) based optimization technique with multiple design constraints. In addition, the sturdiness of the proposed method has been demonstrated in designing a band-pass filter by using an n-branch Quincke tube, a high pass filter and multiple Helmholtz resonators. The performance of the designed acoustic band-pass filter has been shown by investigating the piston-bore defect of a motor-bike using engine noise signature. On the introducing a passive acoustic filter in acoustic based condition monitoring reveals the enhancement in machine learning based fault identification practice significantly. This is also a first attempt of its own kind.

Acoustic comfort in eating establishments

DEFF Research Database (Denmark)

Svensson, David; Jeong, Cheol-Ho; Brunskog, Jonas

2014-01-01

The subjective concept of acoustic comfort in eating establishments has been investigated in this study. The goal was to develop a predictive model for the acoustic comfort, by means of simple objective parameters, while also examining which other subjective acoustic parameters could help explain...... the feeling of acoustic comfort. Through several layers of anal ysis, acoustic comfort was found to be rather complex, and could not be explained entirely by common subjective parameters such as annoyance, intelligibility or privacy. A predictive model for the mean acoustic comfort for an eating establishment...

Springer handbook of acoustics

CERN Document Server

2014-01-01

Acoustics, the science of sound, has developed into a broad interdisciplinary field encompassing the academic disciplines of physics, engineering, psychology, speech, audiology, music, architecture, physiology, neuroscience, and electronics. The Springer Handbook of Acoustics is also in his 2nd edition an unparalleled modern handbook reflecting this richly interdisciplinary nature edited by one of the acknowledged masters in the field, Thomas Rossing. Researchers and students benefit from the comprehensive contents. This new edition of the Handbook features over 11 revised and expanded chapters, new illustrations, and 2 new chapters covering microphone arrays  and acoustic emission.  Updated chapters contain the latest research and applications in, e.g. sound propagation in the atmosphere, nonlinear acoustics in fluids, building and concert hall acoustics, signal processing, psychoacoustics, computer music, animal bioacousics, sound intensity, modal acoustics as well as new chapters on microphone arrays an...

Acoustical Imaging

CERN Document Server

Akiyama, Iwaki

2009-01-01

The 29th International Symposium on Acoustical Imaging was held in Shonan Village, Kanagawa, Japan, April 15-18, 2007. This interdisciplinary Symposium has been taking place every two years since 1968 and forms a unique forum for advanced research, covering new technologies, developments, methods and theories in all areas of acoustics. In the course of the years the volumes in the Acoustical Imaging Series have developed and become well-known and appreciated reference works. Offering both a broad perspective on the state-of-the-art in the field as well as an in-depth look at its leading edge research, this Volume 29 in the Series contains again an excellent collection of seventy papers presented in nine major categories: Strain Imaging Biological and Medical Applications Acoustic Microscopy Non-Destructive Evaluation and Industrial Applications Components and Systems Geophysics and Underwater Imaging Physics and Mathematics Medical Image Analysis FDTD method and Other Numerical Simulations Audience Researcher...

Battlefield acoustics

CERN Document Server

Damarla, Thyagaraju

2015-01-01

This book presents all aspects of situational awareness in a battlefield using acoustic signals. It starts by presenting the science behind understanding and interpretation of sound signals. The book then goes on to provide various signal processing techniques used in acoustics to find the direction of sound source, localize gunfire, track vehicles, and detect people. The necessary mathematical background and various classification and fusion techniques are presented. The book contains majority of the things one would need to process acoustic signals for all aspects of situational awareness in one location. The book also presents array theory, which is pivotal in finding the direction of arrival of acoustic signals. In addition, the book presents techniques to fuse the information from multiple homogeneous/heterogeneous sensors for better detection. MATLAB code is provided for majority of the real application, which is a valuable resource in not only understanding the theory but readers, can also use the code...

First survey of fruit fly (Diptera: Tephritidae) and parasitoid diversity among myrtaceae fruit across the state of Bahia, Brazil

OpenAIRE

Silva, Lidia Nogueira; Santos, Mírian Silva; Dutra, Vivian Siqueira; Araujo, Elton Lucio; Costa, Marco Antonio; Silva, Janisete Gomes

2011-01-01

The objective of this study was to evaluate the diversity of fruit fly (Diptera: Tephritidae) species that use myrtaceous fruit, particularly guava, as hosts in several localities in the state of Bahia and to determine the infestation rates, pupal viability rates, and fruit fly-parasitoid associations. Sampling of myrtaceous fruit was carried out in 24 municipalities in different regions in the state of Bahia. Four fruit fly species, Anastrepha fraterculus, Anastrepha zenildae, Anastrepha sor...

Lack of phenotypic and evolutionary cross-resistance against parasitoids and pathogens in Drosophila melanogaster.

Directory of Open Access Journals (Sweden)

Alex R Kraaijeveld

Full Text Available When organisms are attacked by multiple natural enemies, the evolution of a resistance mechanism to one natural enemy will be influenced by the degree of cross-resistance to another natural enemy. Cross-resistance can be positive, when a resistance mechanism against one natural enemy also offers resistance to another; or negative, in the form of a trade-off, when an increase in resistance against one natural enemy results in a decrease in resistance against another. Using Drosophila melanogaster, an important model system for the evolution of invertebrate immunity, we test for the existence of cross-resistance against parasites and pathogens, at both a phenotypic and evolutionary level.We used a field strain of D. melanogaster to test whether surviving parasitism by the parasitoid Asobara tabida has an effect on the resistance against Beauveria bassiana, an entomopathogenic fungus; and whether infection with the microsporidian Tubulinosema kingi has an effect on the resistance against A. tabida. We used lines selected for increased resistance to A. tabida to test whether increased parasitoid resistance has an effect on resistance against B. bassiana and T. kingi. We used lines selected for increased tolerance against B. bassiana to test whether increased fungal resistance has an effect on resistance against A. tabida.We found no positive cross-resistance or trade-offs in the resistance to parasites and pathogens. This is an important finding, given the use of D. melanogaster as a model system for the evolution of invertebrate immunity. The lack of any cross-resistance to parasites and pathogens, at both the phenotypic and the evolutionary level, suggests that evolution of resistance against one class of natural enemies is largely independent of evolution of resistance against the other.

Mortality risk from entomopathogenic fungi affects oviposition behavior in the parasitoid wasp Trybliographa rapae.

Science.gov (United States)

Rännbäck, Linda-Marie; Cotes, Belen; Anderson, Peter; Rämert, Birgitta; Meyling, Nicolai V

2015-01-01

Biological control of pests in agroecosystems could be enhanced by combining multiple natural enemies. However, this approach might also compromise the control efficacy through intraguild predation (IGP) among the natural enemies. Parasitoids may be able to avoid the risk of unidirectional IGP posed by entomopathogenic fungi through selective oviposition behavior during host foraging. Trybliographa rapae is a larval parasitoid of the cabbage root fly, Delia radicum. Here we evaluated the susceptibility of D. radicum and T. rapae to two species of generalist entomopathogenic fungi, Metarhizium brunneum isolate KVL 04-57 and Beauveria bassiana isolate KVL 03-90. Furthermore, T. rapae oviposition behavior was assessed in the presence of these entomopathogenic fungi either as infected hosts or as infective propagules in the environment. Both fungi were pathogenic to D. radicum larvae and T. rapae adults, but with variable virulence. When host patches were inoculated with M. brunneum conidia in a no-choice situation, more eggs were laid by T. rapae in hosts of those patches compared to control and B. bassiana treated patches. Females that later succumbed to mycosis from either fungus laid significantly more eggs than non-mycosed females, indicating that resources were allocated to increased oviposition due to perceived decreased life expectancy. When presented with a choice between healthy and fungal infected hosts, T. rapae females laid more eggs in healthy larvae than in M. brunneum infected larvae. This was less pronounced for B. bassiana. Based on our results we propose that T. rapae can perceive and react towards IGP risk posed by M. brunneum but not B. bassiana to the foraging female herself and her offspring. Thus, M. brunneum has the potential to be used for biological control against D. radicum with a limited risk to T. rapae populations. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Role of volatiles emitted by host and non-host plants in the foraging behaviour of Dentichasmias busseolae, a pupal parasitoid of the spotted stemborer Chilo partellus

NARCIS (Netherlands)

Gohole, L.S.; Overholt, W.A.; Khan, Z.R.; Vet, L.E.M.

2003-01-01

The role of volatiles from stemborer host and non-host plants in the host-finding process of Dentichasmias busseolae Heinrich (Hymenoptera: Ichneumonidae) a pupal parasitoid of Chilo partellus (Swinhoe) (Lepidoptera: Crambidae) was studied. The non-host plant, molasses grass (Melinis minutiflora

Acoustic insulator for combined well equipment of acoustic and radioactivity logging

International Nuclear Information System (INIS)

Arkad'ev, E.A.; Gorbachev, Yu.I.; Dseban', I.P.; Yagodov, G.I.

1977-01-01

The design of an acoustic insulator for cobined well equipment of acoustic and radioactivity logaing made on the basis of studying the velocity of elastic waves propagation and attenuation in cable structures of various marks is described. It is shown that the cable probe of electric loggign equipment which is recommended as an acoustic insulator for combined well equipment has the necessary sound-insulating properties

Acoustic and streaming velocity components in a resonant waveguide at high acoustic levels.

Science.gov (United States)

Daru, Virginie; Reyt, Ida; Bailliet, Hélène; Weisman, Catherine; Baltean-Carlès, Diana

2017-01-01

Rayleigh streaming is a steady flow generated by the interaction between an acoustic wave and a solid wall, generally assumed to be second order in a Mach number expansion. Acoustic streaming is well known in the case of a stationary plane wave at low amplitude: it has a half-wavelength spatial periodicity and the maximum axial streaming velocity is a quadratic function of the acoustic velocity amplitude at antinode. For higher acoustic levels, additional streaming cells have been observed. Results of laser Doppler velocimetry measurements are here compared to direct numerical simulations. The evolution of axial and radial velocity components for both acoustic and streaming velocities is studied from low to high acoustic amplitudes. Two streaming flow regimes are pointed out, the axial streaming dependency on acoustics going from quadratic to linear. The evolution of streaming flow is different for outer cells and for inner cells. Also, the hypothesis of radial streaming velocity being of second order in a Mach number expansion, is not valid at high amplitudes. The change of regime occurs when the radial streaming velocity amplitude becomes larger than the radial acoustic velocity amplitude, high levels being therefore characterized by nonlinear interaction of the different velocity components.

Controlling sound with acoustic metamaterials

DEFF Research Database (Denmark)

Cummer, Steven A. ; Christensen, Johan; Alù, Andrea

2016-01-01

Acoustic metamaterials can manipulate and control sound waves in ways that are not possible in conventional materials. Metamaterials with zero, or even negative, refractive index for sound offer new possibilities for acoustic imaging and for the control of sound at subwavelength scales....... The combination of transformation acoustics theory and highly anisotropic acoustic metamaterials enables precise control over the deformation of sound fields, which can be used, for example, to hide or cloak objects from incident acoustic energy. Active acoustic metamaterials use external control to create......-scale metamaterial structures and converting laboratory experiments into useful devices. In this Review, we outline the designs and properties of materials with unusual acoustic parameters (for example, negative refractive index), discuss examples of extreme manipulation of sound and, finally, provide an overview...

Education in acoustics in Argentina

Science.gov (United States)

Miyara, Federico

2002-11-01

Over the last decades, education in acoustics (EA) in Argentina has experienced ups and downs due to economic and political issues interfering with long term projects. Unlike other countries, like Chile, where EA has reached maturity in spite of the acoustical industry having shown little development, Argentina has several well-established manufacturers of acoustic materials and equipment but no specific career with a major in acoustics. At the university level, acoustics is taught as a complementary--often elective--course for careers such as architecture, communication engineering, or music. In spite of this there are several research centers with programs covering environmental and community noise, effects of noise on man, acoustic signal processing, musical acoustics and acoustic emission, and several national and international meetings are held each year in which results are communicated and discussed. Several books on a variety of topics such as sound system, architectural acoustics, and noise control have been published as well. Another chapter in EA is technical and vocational education, ranging between secondary and postsecondary levels, with technical training on sound system operation or design. Over the last years there have been several attempts to implement master degrees in acoustics or audio engineering, with little or no success.

Biology of Blepyrus clavicornis (Compere (Hymenoptera: Encyrtidae, a parasitoid of Pseudococcus viburni (Signoret (Hemiptera: Pseudococcidae

Directory of Open Access Journals (Sweden)

Vitor Pacheco da Silva

Full Text Available Abstract Encyrtids (Hymenoptera: Encyrtidae are the most important and diverse group of natural enemies of mealybugs (Hemiptera: Pseudococcidae. Blepyrus clavicornis (Compere is the most common parasitoid associated with Pseudococcus viburni (Signoret in the Serra Gaúcha region, Brazil. We conducted laboratory studies to assess the development time, sex ratio, adult longevity, host stage selection for parasitism, and effect of food on the longevity of adult females of B. clavicornis. The experiments were conducted in a climate chamber at 25 ± 1 °C, 70 ± 10% RH and 12:12 L:D photoperiod. The solitary parasitoid B. clavicornis parasitized third-instar and adult female stages of P. viburni. The development time was more than 30 days (31.75 ± 0.38 for females and 30.02 ± 0.34 for males when B. clavicornis laid eggs in adult mealybug females, and 35 days (36.50 ± 0.50 for females and 34.24 ± 0.43 for males on third-instar mealybug nymphs. The wasps did not survive longer than four days when they were fed only water, while females survived for about 30 days when fed with honey. The lifespan of females is about 20 days longer than the lifespan of males. Although B. clavicornis can provide significant natural control, reducing the number of individuals in the next generation by parasitizing advanced mealybug instars, we consider it unpromising for use in applied biological-control programs. Furthermore, the predominance of males in the progeny observed here suggests that P. viburni may not be the most suitable or preferred host for B. clavicornis.

Review of Progress in Acoustic Levitation

Science.gov (United States)

Andrade, Marco A. B.; Pérez, Nicolás; Adamowski, Julio C.

2018-04-01

Acoustic levitation uses acoustic radiation forces to counteract gravity and suspend objects in mid-air. Although acoustic levitation was first demonstrated almost a century ago, for a long time, it was limited to objects much smaller than the acoustic wavelength levitating at fixed positions in space. Recent advances in acoustic levitation now allow not only suspending but also rotating and translating objects in three dimensions. Acoustic levitation is also no longer restricted to small objects and can now be employed to levitate objects larger than the acoustic wavelength. This article reviews the progress of acoustic levitation, focusing on the working mechanism of different types of acoustic levitation devices developed to date. We start with a brief review of the theory. Then, we review the acoustic levitation methods to suspend objects at fixed positions, followed by the techniques that allow the manipulation of objects. Finally, we present a brief summary and offer some future perspectives for acoustic levitation.

Diversity and indices of infestation of fruit flies and their parasitoids in six coffee cultivars in the city of Bom Jesus of Itabapoana, RJ

Directory of Open Access Journals (Sweden)

Patrícia Sobral Silva

2011-11-01

Full Text Available This study focuses one of the most important pests of world fruit crop: the fruit flies, however, there are few studies concerned with their association with coffee fruit. This study was carried out in the municipality of Bom Jesus do Itabapoana, in the Northwest Region of Rio de Janeiro State, Brazil, aiming at determining the species which occur in the coffee plantations of this region, their natural infestation indices and the natural parasitism of these species. Mature fruits of six cultivars of Arabic coffee (‘Acauã’ ‘Catuaí Amarelo’, ‘Catuaí Vermelho’, ‘Catuaí 785’, ‘Mundo Novo’e ‘2SL Vermelho’ were collected. All cultivars evaluated were infested by fruit flies, which were associated with only one species of parasitoid in each cultivar. A total of 1,749 puparia were obtained and from which emerged 460 adults, being 441 specimens of fruit flies and 19 parasitoids. Four species of fruit flies were obtained: Anastrepha fraterculus (Wiedemman, 1830, Anastrepha sororcula (Zucchi, 1979, Ceratitis capitata (Wiedemann, 1824, (Tephritidae and Neosilba pendula Bezzi, 1919 (Lonchaeidae. The mean natural infestation index of the coffee fruits by fruit flies was of 291.5 puparia/kg and 0.4 puparia/fruit. There was a predominance of A. fraterculus over C. capitata, which was more frequent only in ‘Catuaí Vermelho’ and ‘Catuaí 785’. All parasitoids belong to the family Braconidae [Asobara sp., Opius bellus (Gahan, 1930 and Doryctobrachon areolatus (Szépligeti, 1911], which were responsible for a very low level of natural parasitism (1.1%.

[Biological aspects of Cirrospilus neotropicus Diez & Fidalgo (Hymenoptera: Eulophidae), parasitoid of Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae)].

Science.gov (United States)

Foelkel, Ester; Redaelli, Luiza R; Jahnke, Simone M; Losekann, Paula B

2008-01-01

The biology of Cirrospilus neotropicus Diez & Fidalgo reared on third instar Phyllocnistis citrella Stainton larvae having Citrus limonia Osbeck as host plant, was evaluated under controlled conditions (25 +/- 1 masculineC; 12h photophase). The survival, immatures development, longevity, sex ratio, host feeding and oviposition ratio of C. neotropicus, were registered. Two groups of parasitoid females were evaluated: one, with parasitoids obtained from P. citrella pupae collected in citrus orchards and the other group came from laboratory rearing. These females, after mating, were maintained individually on gerbox containers with honey and pollen as food source. At each 48h, 12 P. citrella larvae were changed. The average biological cycle of the female progenies from orchard and laboratory generation groups were 11.8 and 11.6 days, respectively. The males progenies had biological cycles of 11.6 and 10.9 days, as well. The shortest immature survival period, for both studied groups was the larval (57.3% - orchard group and 57.4% - lab group). The mated females average longevity (21.8 days) was superior than the non mated ones (9.1 days) for the orchard group. The average daily oviposition rate for this last group was also significantly superior (2.8 eggs /day) than the lab group (1.6 eggs / day). The same trend was observed for the average daily host feeding rate (1.7 larvae /day for the orchard group and 0.9 larvae/ day for the lab group). These data suggest that C. neotropicus have potencial as a biological control agent of P. citrella.

Interaction of surface plasmon polaritons and acoustic waves inside an acoustic cavity.

Science.gov (United States)

Khokhlov, Nikolai; Knyazev, Grigoriy; Glavin, Boris; Shtykov, Yakov; Romanov, Oleg; Belotelov, Vladimir

2017-09-15

In this Letter, we introduce an approach for manipulation of active plasmon polaritons via acoustic waves at sub-terahertz frequency range. The acoustic structures considered are designed as phononic Fabry-Perot microresonators where mirrors are presented with an acoustic superlattice and the structure's surface, and a plasmonic grating is placed on top of the acoustic cavity so formed. It provides phonon localization in the vicinity of the plasmonic grating at frequencies within the phononic stop band enhancing phonon-light interaction. We consider phonon excitation by shining a femtosecond laser pulse on the plasmonic grating. Appropriate theoretical model was used to describe the acoustic process caused by the pump laser pulse in the GaAs/AlAs-based acoustic cavity with a gold grating on top. Strongest modulation is achieved upon excitation of propagating surface plasmon polaritons and hybridization of propagating and localized plasmons. The relative changes in the optical reflectivity of the structure are more than an order of magnitude higher than for the structure without the plasmonic film.

Acoustic biosensors.

Science.gov (United States)

Fogel, Ronen; Limson, Janice; Seshia, Ashwin A

2016-06-30

Resonant and acoustic wave devices have been researched for several decades for application in the gravimetric sensing of a variety of biological and chemical analytes. These devices operate by coupling the measurand (e.g. analyte adsorption) as a modulation in the physical properties of the acoustic wave (e.g. resonant frequency, acoustic velocity, dissipation) that can then be correlated with the amount of adsorbed analyte. These devices can also be miniaturized with advantages in terms of cost, size and scalability, as well as potential additional features including integration with microfluidics and electronics, scaled sensitivities associated with smaller dimensions and higher operational frequencies, the ability to multiplex detection across arrays of hundreds of devices embedded in a single chip, increased throughput and the ability to interrogate a wider range of modes including within the same device. Additionally, device fabrication is often compatible with semiconductor volume batch manufacturing techniques enabling cost scalability and a high degree of precision and reproducibility in the manufacturing process. Integration with microfluidics handling also enables suitable sample pre-processing/separation/purification/amplification steps that could improve selectivity and the overall signal-to-noise ratio. Three device types are reviewed here: (i) bulk acoustic wave sensors, (ii) surface acoustic wave sensors, and (iii) micro/nano-electromechanical system (MEMS/NEMS) sensors. © 2016 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

Antagonistic Interactions between the African Weaver Ant Oecophylla longinoda and the Parasitoid Anagyrus pseudococci Potentially Limits Suppression of the Invasive Mealybug Rastrococcus iceryoides

Directory of Open Access Journals (Sweden)

Chrysantus M. Tanga

2015-12-01

Full Text Available The ant Oecophylla longinoda Latreille forms a trophobiotic relationship with the invasive mealybug Rastrococus iceryoides Green and promotes the latter’s infestations to unacceptable levels in the presence of their natural enemies. In this regard, the antagonistic interactions between the ant and the parasitoid Anagyrus pseudococci Girault were assessed under laboratory conditions. The percentage of parasitism of R. iceryoides by A. pseudococci was significantly higher on “ant-excluded” treatments (86.6% ± 1.27% compared to “ant-tended” treatments (51.4% ± 4.13%. The low female-biased sex-ratio observed in the “ant-tended” treatment can be attributed to ants’ interference during the oviposition phase, which disrupted parasitoids’ ability to fertilize eggs. The mean foraging time, host handling time and number of successful oviposition in “ant-excluded” treatment were significantly higher compared to “ant-tended” treatments. When ant workers were allowed access to sterilized sand grains, mummified and unmummified R. iceryoides, they selectively removed the mummified mealybugs, indicating that they recognized the mummies as potential foods (1.2 ± 0.46 to 7.8 ± 1.17 mummies at 10 min intervals for 2 h. Percentage emergence from mummified R. iceryoides removed by the ants was significantly lower compared to emergence from mummies not exposed to ants. Although, host seeking parasitoids frequently evaded attacks, some were killed by the foraging ant workers (2.0 ± 0.38 to 6.0 ± 0.88 at 10 min intervals for 2 h. These results suggest for the first time that the presence of O. longinoda has a detrimental effect on the abundance, reproductive success and possibly oviposition strategy of female parasitoids, which might be a delimiting factor in field conditions if both natural enemies are to be recommended for use within the same agro-ecosystem.

Evidence for divergence in cuticular hydrocarbon sex pheromone between California and Mississippi (United States of America) populations of bark beetle parasitoid Roptrocerus xylophagorum (Hymenoptera: Pteromalidae).

Science.gov (United States)

Brian Sullivan; Nadir Erbilgin

2014-01-01

Roptrocerus xylophagorum (Ratzeburg) (Hymenoptera: Pteromalidae) is a common Holarctic parasitoid of the larvae and pupae of bark beetles (Coleoptera: Curculionidae: Scotytinae). In no-choice laboratory bioassays, we found that male wasps derived either from northern California or southwestern Mississippi, United States of America more frequently displayed sexual...

Biología y ecología de Telenomus sp.(Hymenoptera: scelionidae) parasitoide de huevos de Opsiphanes cassina felder (Lepidoptera: nymphalidae: brassolinae) / Biological and ecology of Telenomus sp. (hymenoptera: scelionidae) parasitoid of eggs of Opsiphanes cassina felder. (Lepidoptera: nymphalidae: brassolinae)

OpenAIRE

Guarin Campo, Arnulfo

2010-01-01

En la zona palmera del municipio de Puerto Wilches, departamento de Santander, Colombia, 60–80% de humedad relativa, 2200 horas de brillo solar y 27.4 ºC de temperatura; se estudiaron los principales aspectos biológicos y ecológicos de Telenomus sp., parasitoide de huevos de Opsiphanes cassina Felder, (su fauna y flora asociada). Los resultados demostraron que Telenomus sp. parasita huevos de insectos de la familia Nymphalidae relacionados al cultivo de la palma de aceite y huevos de Alcaeor...

Cave acoustics in prehistory: Exploring the association of Palaeolithic visual motifs and acoustic response.

Science.gov (United States)

Fazenda, Bruno; Scarre, Chris; Till, Rupert; Pasalodos, Raquel Jiménez; Guerra, Manuel Rojo; Tejedor, Cristina; Peredo, Roberto Ontañón; Watson, Aaron; Wyatt, Simon; Benito, Carlos García; Drinkall, Helen; Foulds, Frederick

2017-09-01

During the 1980 s, acoustic studies of Upper Palaeolithic imagery in French caves-using the technology then available-suggested a relationship between acoustic response and the location of visual motifs. This paper presents an investigation, using modern acoustic measurement techniques, into such relationships within the caves of La Garma, Las Chimeneas, La Pasiega, El Castillo, and Tito Bustillo in Northern Spain. It addresses methodological issues concerning acoustic measurement at enclosed archaeological sites and outlines a general framework for extraction of acoustic features that may be used to support archaeological hypotheses. The analysis explores possible associations between the position of visual motifs (which may be up to 40 000 yrs old) and localized acoustic responses. Results suggest that motifs, in general, and lines and dots, in particular, are statistically more likely to be found in places where reverberation is moderate and where the low frequency acoustic response has evidence of resonant behavior. The work presented suggests that an association of the location of Palaeolithic motifs with acoustic features is a statistically weak but tenable hypothesis, and that an appreciation of sound could have influenced behavior among Palaeolithic societies of this region.

The effects of two counterpropagating surface acoustic wave beams on single electron acoustic charge transport

International Nuclear Information System (INIS)

He Jianhong; Guo Huazhong; Song Li; Zhang Wei; Gao Jie; Lu Chuan

2010-01-01

We present a comprehensive study of the effects of two counterpropagating surface acoustic waves on the acoustoelectric current of single electron transport devices. A significant improvement in the accuracy of current quantization is achieved as a result of an additional surface acoustic wave beam. The experiments reveal the sinusoidally periodical modulation in the acoustoelectric current characteristic as a function of the relative phase of the two surface acoustic wave beams. Besides, by using standing surface acoustic waves, the acoustoelectric current is detected which we consider as the so-called anomalous acoustoelectric current produced by acoustic wave mechanical deformations. This kind current is contributed to one component of the acoustoelectric current in surface acoustic wave device, which could enable us to establish a more adequate description of acoustoelectric effects on single-electron acoustic charge transport.

Localized Acoustic Surface Modes

KAUST Repository

Farhat, Mohamed

2015-08-04

We introduce the concept of localized acoustic surface modes (ASMs). We demonstrate that they are induced on a two-dimensional cylindrical rigid surface with subwavelength corrugations under excitation by an incident acoustic plane wave. Our results show that the corrugated rigid surface is acoustically equivalent to a cylindrical scatterer with uniform mass density that can be represented using a Drude-like model. This, indeed, suggests that plasmonic-like acoustic materials can be engineered with potential applications in various areas including sensing, imaging, and cloaking.

Acoustic Signals and Systems

DEFF Research Database (Denmark)

2008-01-01

The Handbook of Signal Processing in Acoustics will compile the techniques and applications of signal processing as they are used in the many varied areas of Acoustics. The Handbook will emphasize the interdisciplinary nature of signal processing in acoustics. Each Section of the Handbook...... will present topics on signal processing which are important in a specific area of acoustics. These will be of interest to specialists in these areas because they will be presented from their technical perspective, rather than a generic engineering approach to signal processing. Non-specialists, or specialists...... from different areas, will find the self-contained chapters accessible and will be interested in the similarities and differences between the approaches and techniques used in different areas of acoustics....

Optical measurement of acoustic radiation pressure of the near-field acoustic levitation through transparent object

OpenAIRE

Nakamura, Satoshi; Furusawa, Toshiaki; Sasao, Yasuhiro; Katsura, Kogure; Naoki, Kondo

2013-01-01

It is known that macroscopic objects can be levitated for few to several hundred micrometers by near-field acoustic field and this phenomenon is called near-field acoustic levitation (NFAL). Although there are various experiments conducted to measure integrated acoustic pressure on the object surface, up to now there was no direct method to measure pressure distribution. In this study we measured the acoustic radiation pressure of the near-field acoustic levitation via pressure-sensitive paint.

Observation of self-excited acoustic vortices in defect-mediated dust acoustic wave turbulence.

Science.gov (United States)

Tsai, Ya-Yi; I, Lin

2014-07-01

Using the self-excited dust acoustic wave as a platform, we demonstrate experimental observation of self-excited fluctuating acoustic vortex pairs with ± 1 topological charges through spontaneous waveform undulation in defect-mediated turbulence for three-dimensional traveling nonlinear longitudinal waves. The acoustic vortex pair has helical waveforms with opposite chirality around the low-density hole filament pair in xyt space (the xy plane is the plane normal to the wave propagation direction). It is generated through ruptures of sequential crest surfaces and reconnections with their trailing ruptured crest surfaces. The initial rupture is originated from the amplitude reduction induced by the formation of the kinked wave crest strip with strong stretching through the undulation instability. Increasing rupture causes the separation of the acoustic vortex pair after generation. A similar reverse process is followed for the acoustic vortex annihilating with the opposite-charged acoustic vortex from the same or another pair generation.

Recombination and its impact on the genome of the haplodiploid parasitoid wasp Nasonia.

Directory of Open Access Journals (Sweden)

Oliver Niehuis

2010-01-01

Full Text Available Homologous meiotic recombination occurs in most sexually reproducing organisms, yet its evolutionary advantages are elusive. Previous research explored recombination in the honeybee, a eusocial hymenopteran with an exceptionally high genome-wide recombination rate. A comparable study in a non-social member of the Hymenoptera that would disentangle the impact of sociality from Hymenoptera-specific features such as haplodiploidy on the evolution of the high genome-wide recombination rate in social Hymenoptera is missing. Utilizing single-nucleotide polymorphisms (SNPs between two Nasonia parasitoid wasp genomes, we developed a SNP genotyping microarray to infer a high-density linkage map for Nasonia. The map comprises 1,255 markers with an average distance of 0.3 cM. The mapped markers enabled us to arrange 265 scaffolds of the Nasonia genome assembly 1.0 on the linkage map, representing 63.6% of the assembled N. vitripennis genome. We estimated a genome-wide recombination rate of 1.4-1.5 cM/Mb for Nasonia, which is less than one tenth of the rate reported for the honeybee. The local recombination rate in Nasonia is positively correlated with the distance to the center of the linkage groups, GC content, and the proportion of simple repeats. In contrast to the honeybee genome, gene density in the parasitoid wasp genome is positively associated with the recombination rate; regions of low recombination are characterized by fewer genes with larger introns and by a greater distance between genes. Finally, we found that genes in regions of the genome with a low recombination frequency tend to have a higher ratio of non-synonymous to synonymous substitutions, likely due to the accumulation of slightly deleterious non-synonymous substitutions. These findings are consistent with the hypothesis that recombination reduces interference between linked sites and thereby facilitates adaptive evolution and the purging of deleterious mutations. Our results imply

Acoustic Emission Technology and Application

International Nuclear Information System (INIS)

Joo, Y. S.; Lim, S. H.; Eom, H. S.; Kim, J. H.; Jung, H. K.

2003-10-01

Acoustic emission is the elastic wave that is generated by the rapid release of energy from the localized sources within a material. After the observation of acoustic emission phenomenon in 1950, the research and further investigation had been performed. Acoustic emission examination becomes a rapidly matured nondestructive testing method with demonstrated capabilities for characterizing material behavior and for detecting the defect. It is of interest as a possible passive monitoring technique for detecting, locating and characterizing the defects in component and structure. Acoustic emission technology has recently strengthened the on-line monitoring application for the detection of incipient failures and the assurance of structural integrity. The field of acoustic emission testing is still growing vigorously and presents many challenges. Especially, acoustic emission has been successfully applied in the leak detection of primary pressure boundary of nuclear power plants. In this state-of-art report, the principle, measurement and field applications of acoustic emission technique is reviewed and summarized. Acoustic emission technology will contribute to the assurance of nuclear safety as the on-line monitoring technique of structural integrity of NSSS components and structures

Acoustic building infiltration measurement system

Science.gov (United States)

Muehleisen, Ralph T.; Raman, Ganesh

2018-04-10

Systems and methods of detecting and identifying a leak from a container or building. Acoustic pressure and velocity are measured. Acoustic properties are acquired from the measured values. The acoustic properties are converted to infiltration/leakage information. Nearfield Acoustic Holography (NAH) may be one method to detect the leakages from a container by locating the noise sources.

The accidental (acoustical) tourist

Science.gov (United States)

Van Kirk, Wayne

2002-11-01

The acoustical phenomenon observed at an ancient temple in the Great Ball Court at Chichen Itza was described as ''little short of amazing--an ancient whispering gallery'' by Silvanus G. Morley, leader of the Carnegie Institute's archaeological team that excavated and restored these structures in the 1920s. Since then, many others have experienced the extraordinary acoustics at Chichen Itza and other Maya sites. Despite these reports, archaeologists and acousticians have until recently shown little interest in understanding these phenomena. After experiencing Chichen Itza's remarkable acoustics as a tourist in 1994, the author commenced collecting and disseminating information about acoustical phenomena there and at other Mayan sites, hoping to stimulate interest among archaeologists and acousticians. Were these designs accidental or intentional? If intentional, how was the knowledge obtained? How were acoustical features used? This paper highlights the author's collection of anecdotal reports of mysterious Mayan acoustics (http://http://www.ianlawton.com/pa1.htm), recommended reading for scientists and engineers who wish to pursue this fascinating study. Also recounted are some of the reactions of archaeologists-ranging from curious, helpful, and insightful to humorous and appalling--to outsiders' efforts to bring serious scientific attention to the new field of acoustical archaeology.

Acoustic field modulation in regenerators

Science.gov (United States)

Hu, J. Y.; Wang, W.; Luo, E. C.; Chen, Y. Y.

2016-12-01

The regenerator is a key component that transfers energy between heat and work. The conversion efficiency is significantly influenced by the acoustic field in the regenerator. Much effort has been spent to quantitatively determine this influence, but few comprehensive experimental verifications have been performed because of difficulties in modulating and measuring the acoustic field. In this paper, a method requiring two compressors is introduced and theoretically investigated that achieves acoustic field modulation in the regenerator. One compressor outputs the acoustic power for the regenerator; the other acts as a phase shifter. A RC load dissipates the acoustic power out of both the regenerator and the latter compressor. The acoustic field can be modulated by adjusting the current in the two compressors and opening the RC load. The acoustic field is measured with pressure sensors instead of flow-field imaging equipment, thereby greatly simplifying the experiment.

Ares I Scale Model Acoustic Tests Instrumentation for Acoustic and Pressure Measurements

Science.gov (United States)

Vargas, Magda B.; Counter, Douglas D.

2011-01-01

The Ares I Scale Model Acoustic Test (ASMAT) was a development test performed at the Marshall Space Flight Center (MSFC) East Test Area (ETA) Test Stand 116. The test article included a 5% scale Ares I vehicle model and tower mounted on the Mobile Launcher. Acoustic and pressure data were measured by approximately 200 instruments located throughout the test article. There were four primary ASMAT instrument suites: ignition overpressure (IOP), lift-off acoustics (LOA), ground acoustics (GA), and spatial correlation (SC). Each instrumentation suite incorporated different sensor models which were selected based upon measurement requirements. These requirements included the type of measurement, exposure to the environment, instrumentation check-outs and data acquisition. The sensors were attached to the test article using different mounts and brackets dependent upon the location of the sensor. This presentation addresses the observed effect of the sensors and mounts on the acoustic and pressure measurements.

Agorá Acoustics - Effects of arcades on the acoustics of public squares

DEFF Research Database (Denmark)

Paini, Dario; Gade, Anders Christian; Rindel, Jens Holger

2005-01-01

This paper is part of a PhD work, dealing with the acoustics of the public squares (‘Agorá Acoustics’), especially when music (amplified or not) is played. Consequently, our approach will be to evaluate public squares using the same set of acoustics concepts for subjective evaluation and objective...... measurements as applied for concert halls and theatres. In this paper the acoustical effects of arcades will be studied, in terms of reverberation (EDT and T30), clarity (C80), intelligibility (STI) and other acoustical parameters. For this purpose, also the theory of coupled rooms is applied and compared...... with results. An acoustic modelling program, ODEON 7.0, was used for this investigation. Three different sizes of public squares were considered. In order to evaluate the ‘real’ effects of the arcades on the open square, models of all three squares were designed both with and without arcades. The sound source...

Understanding acoustics an experimentalist’s view of acoustics and vibration

CERN Document Server

Garrett, Steven L

2017-01-01

This textbook provides a unified approach to acoustics and vibration suitable for use in advanced undergraduate and first-year graduate courses on vibration and fluids. The book includes thorough treatment of vibration of harmonic oscillators, coupled oscillators, isotropic elasticity, and waves in solids including the use of resonance techniques for determination of elastic moduli. Drawing on 35 years of experience teaching introductory graduate acoustics at the Naval Postgraduate School and Penn State, the author presents a hydrodynamic approach to the acoustics of sound in fluids that provides a uniform methodology for analysis of lumped-element systems and wave propagation that can incorporate attenuation mechanisms and complex media. This view provides a consistent and reliable approach that can be extended with confidence to more complex fluids and future applications. Understanding Acoustics opens with a mathematical introduction that includes graphing and statistical uncertainty, followed by five chap...

Investigation into the Effect of Acoustic Radiation Force and Acoustic Streaming on Particle Patterning in Acoustic Standing Wave Fields

Directory of Open Access Journals (Sweden)

Shilei Liu

2017-07-01

Full Text Available Acoustic standing waves have been widely used in trapping, patterning, and manipulating particles, whereas one barrier remains: the lack of understanding of force conditions on particles which mainly include acoustic radiation force (ARF and acoustic streaming (AS. In this paper, force conditions on micrometer size polystyrene microspheres in acoustic standing wave fields were investigated. The COMSOL® Mutiphysics particle tracing module was used to numerically simulate force conditions on various particles as a function of time. The velocity of particle movement was experimentally measured using particle imaging velocimetry (PIV. Through experimental and numerical simulation, the functions of ARF and AS in trapping and patterning were analyzed. It is shown that ARF is dominant in trapping and patterning large particles while the impact of AS increases rapidly with decreasing particle size. The combination of using both ARF and AS for medium size particles can obtain different patterns with only using ARF. Findings of the present study will aid the design of acoustic-driven microfluidic devices to increase the diversity of particle patterning.

Investigation into the Effect of Acoustic Radiation Force and Acoustic Streaming on Particle Patterning in Acoustic Standing Wave Fields

Science.gov (United States)

Yang, Yanye; Ni, Zhengyang; Guo, Xiasheng; Luo, Linjiao; Tu, Juan; Zhang, Dong

2017-01-01

Acoustic standing waves have been widely used in trapping, patterning, and manipulating particles, whereas one barrier remains: the lack of understanding of force conditions on particles which mainly include acoustic radiation force (ARF) and acoustic streaming (AS). In this paper, force conditions on micrometer size polystyrene microspheres in acoustic standing wave fields were investigated. The COMSOL® Mutiphysics particle tracing module was used to numerically simulate force conditions on various particles as a function of time. The velocity of particle movement was experimentally measured using particle imaging velocimetry (PIV). Through experimental and numerical simulation, the functions of ARF and AS in trapping and patterning were analyzed. It is shown that ARF is dominant in trapping and patterning large particles while the impact of AS increases rapidly with decreasing particle size. The combination of using both ARF and AS for medium size particles can obtain different patterns with only using ARF. Findings of the present study will aid the design of acoustic-driven microfluidic devices to increase the diversity of particle patterning. PMID:28753955

Deep Water Acoustics

Science.gov (United States)

2016-06-28

the Deep Water project and participate in the NPAL Workshops, including Art Baggeroer (MIT), J. Beron- Vera (UMiami), M. Brown (UMiami), T...Kathleen E . Wage. The North Pacific Acoustic Laboratory deep-water acoustic propagation experiments in the Philippine Sea. J. Acoust. Soc. Am., 134(4...estimate of the angle α during PhilSea09, made from ADCP measurements at the site of the DVLA. Sim. A B1 B2 B3 C D E F Prof. # 0 4 4 4 5 10 16 20 α

Acoustic Levitation With Less Equipment

Science.gov (United States)

Barmatz, M. B.; Jacobi, N.

1983-01-01

Certain chamber shapes require fewer than three acoustic drivers. Levitation at center of spherical chamber attained using only one acoustic driver. Exitation of lowest spherical mode produces asymmetric acoustic potential well.

Anisotropy of acoustic properties in paratellurite

International Nuclear Information System (INIS)

Parygin, Vladimir N.

1996-01-01

One of the peculiarities of the TeO 2 crystal consists of its strong acoustic anisotropy. This anisotropy demonstrates itself by acoustic energy walk-off and anisotropic distortion of an acoustic beam. Four constants completely characterise the acoustic anisotropy of the medium. In this paper these constants are calculated for various directions of the acoustic beam in crystal. (authors)

Variable-Position Acoustic Levitation

Science.gov (United States)

Barmatz, M. B.; Stoneburner, J. D.; Jacobi, N.; Wang, T. G.

1983-01-01

Method of acoustic levitation supports objects at positions other than acoustic nodes. Acoustic force is varied so it balances gravitational (or other) force, thereby maintaining object at any position within equilibrium range. Levitation method applicable to containerless processing. Such objects as table-tennis balls, hollow plastic spheres, and balsa-wood spheres levitated in laboratory by new method.

Photo-acoustic and video-acoustic methods for sensing distant sound sources

Science.gov (United States)

Slater, Dan; Kozacik, Stephen; Kelmelis, Eric

2017-05-01

Long range telescopic video imagery of distant terrestrial scenes, aircraft, rockets and other aerospace vehicles can be a powerful observational tool. But what about the associated acoustic activity? A new technology, Remote Acoustic Sensing (RAS), may provide a method to remotely listen to the acoustic activity near these distant objects. Local acoustic activity sometimes weakly modulates the ambient illumination in a way that can be remotely sensed. RAS is a new type of microphone that separates an acoustic transducer into two spatially separated components: 1) a naturally formed in situ acousto-optic modulator (AOM) located within the distant scene and 2) a remote sensing readout device that recovers the distant audio. These two elements are passively coupled over long distances at the speed of light by naturally occurring ambient light energy or other electromagnetic fields. Stereophonic, multichannel and acoustic beam forming are all possible using RAS techniques and when combined with high-definition video imagery it can help to provide a more cinema like immersive viewing experience. A practical implementation of a remote acousto-optic readout device can be a challenging engineering problem. The acoustic influence on the optical signal is generally weak and often with a strong bias term. The optical signal is further degraded by atmospheric seeing turbulence. In this paper, we consider two fundamentally different optical readout approaches: 1) a low pixel count photodiode based RAS photoreceiver and 2) audio extraction directly from a video stream. Most of our RAS experiments to date have used the first method for reasons of performance and simplicity. But there are potential advantages to extracting audio directly from a video stream. These advantages include the straight forward ability to work with multiple AOMs (useful for acoustic beam forming), simpler optical configurations, and a potential ability to use certain preexisting video recordings. However

Effects of volatiles from Maruca vitrata larvae and caterpillar-infested flowers of their host plant Vigna unguiculata on the foraging behavior of the parasitoid Apanteles taragamae

NARCIS (Netherlands)

Dannon, A.E.; Tamò, M.; Huis, van A.; Dicke, M.

2010-01-01

The parasitoid wasp Apanteles taragamae is a promising candidate for the biological control of the legume pod borer Maruca vitrata, which recently has been introduced into Benin. The effects of volatiles from cowpea and peabush flowers and Maruca vitrata larvae on host selection behavior of the

Magnetoactive Acoustic Metamaterials.

Science.gov (United States)

Yu, Kunhao; Fang, Nicholas X; Huang, Guoliang; Wang, Qiming

2018-04-11

Acoustic metamaterials with negative constitutive parameters (modulus and/or mass density) have shown great potential in diverse applications ranging from sonic cloaking, abnormal refraction and superlensing, to noise canceling. In conventional acoustic metamaterials, the negative constitutive parameters are engineered via tailored structures with fixed geometries; therefore, the relationships between constitutive parameters and acoustic frequencies are typically fixed to form a 2D phase space once the structures are fabricated. Here, by means of a model system of magnetoactive lattice structures, stimuli-responsive acoustic metamaterials are demonstrated to be able to extend the 2D phase space to 3D through rapidly and repeatedly switching signs of constitutive parameters with remote magnetic fields. It is shown for the first time that effective modulus can be reversibly switched between positive and negative within controlled frequency regimes through lattice buckling modulated by theoretically predicted magnetic fields. The magnetically triggered negative-modulus and cavity-induced negative density are integrated to achieve flexible switching between single-negative and double-negative. This strategy opens promising avenues for remote, rapid, and reversible modulation of acoustic transportation, refraction, imaging, and focusing in subwavelength regimes. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Electron/electron acoustic instability

International Nuclear Information System (INIS)

Gary, S.P.

1987-01-01

The electron acoustic wave becomes a normal mode of an unmagnetized collisionless plasma in the presence of two electron components with similar densities, but strongly disparate temperatures. The characteristic frequency of this mode is the plasma frequency of the cooler electron component. If these two electron components have a relative drift speed several times the thermal speed of the cooler component, the electron/electron acoustic instability may arise. This paper describes the parametric dependences of the threshold drift speed and maximum growth rate of this instability, and compares these with the same properties of the electron/ion acoustic instability. Under the condition of zero current, the electron/ion acoustic instability typically has the lower threshold drift speed, so that observation of the electron/electron acoustic instability is a strong indication of the presence of an electrical current in the plasma

Acoustic imaging system

Science.gov (United States)

Smith, Richard W.

1979-01-01

An acoustic imaging system for displaying an object viewed by a moving array of transducers as the array is pivoted about a fixed point within a given plane. A plurality of transducers are fixedly positioned and equally spaced within a laterally extending array and operatively directed to transmit and receive acoustic signals along substantially parallel transmission paths. The transducers are sequentially activated along the array to transmit and receive acoustic signals according to a preestablished sequence. Means are provided for generating output voltages for each reception of an acoustic signal, corresponding to the coordinate position of the object viewed as the array is pivoted. Receptions from each of the transducers are presented on the same display at coordinates corresponding to the actual position of the object viewed to form a plane view of the object scanned.

Priming of cowpea volatile emissions with defense inducers enhances the plant's attractiveness to parasitoids when attacked by caterpillars.

Science.gov (United States)

Sobhy, Islam S; Bruce, Toby Ja; Turlings, Ted Cj

2018-04-01

The manipulation of herbivore-induced volatile organic compounds (HI-VOCs) via the application of the inducers benzo(1,2,3)thiadiazole-7-carbothioic acid S-methyl ester (BTH) and laminarin (β-1,3-glucan) is known to enhance the attractiveness of caterpillar-damaged cotton and maize plants to parasitoids. To test if this is also the case for legumes, we treated cowpea (Vigna unguiculata var. unguiculata) with these inducers and studied the effects on HI-VOC emissions and the attraction of three generalist endoparasitoids. After the inducers had been applied and the plants subjected to either real or mimicked herbivory by Spodoptera littoralis caterpillars, females of the parasitoids Campoletis sonorensis and Microplitis rufiventris showed a strong preference for BTH-treated plants, whereas Cotesia females were strongly attracted to both BTH- and laminarin-treated plants with real or mimicked herbivory. Treated plants emitted more of certain HI-VOCs, but considerably less indole and linalool and less of several sesquiterpenes. Multivariate data analysis revealed that enhanced wasp attraction after treatment was correlated with high relative concentrations of nonanal, α-pinene, (E)-β-ocimene and (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT), and with low relative concentrations of indole, (S)-linalool and (E)-β-farnesene. Inducer treatments had no significant effect on leaf consumption by the caterpillars. Our findings confirm that treating cowpea plants with inducers can enhance their attractiveness to biological control agents. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Perspective: Acoustic metamaterials in transition

KAUST Repository

Wu, Ying

2017-12-15

Acoustic metamaterials derive their novel characteristics from the interaction between acoustic waves with designed structures. Since its inception seventeen years ago, the field has been driven by fundamental geometric and physical principles that guide the structure design rules as well as provide the basis for wave functionalities. Recent examples include resonance-based acoustic metasurfaces that offer flexible control of acoustic wave propagation such as focusing and re-direction; parity-time (PT)-symmetric acoustics that utilizes the general concept of pairing loss and gain to achieve perfect absorption at a single frequency; and topological phononics that can provide one-way edge state propagation. However, such novel functionalities are not without constraints. Metasurface elements rely on resonances to enhance their coupling to the incident wave; hence, its functionality is limited to a narrow frequency band. Topological phononics is the result of the special lattice symmetry that must be fixed at the fabrication stage. Overcoming such constraints naturally forms the basis for further developments. We identify two emergent directions: Integration of acoustic metamaterial elements for achieving broadband characteristics as well as acoustic wave manipulation tasks more complex than the single demonstrative functionality; and active acoustic metamaterials that can adapt to environment as well as to go beyond the constraints on the passive acoustic metamaterials. Examples of a successful recent integration of multi-resonators in achieving broadband sound absorption can be found in optimal sound-absorbing structures, which utilize causality constraint as a design tool in realizing the target-set absorption spectrum with a minimal sample thickness. Active acoustic metamaterials have also demonstrated the capability to tune bandgaps as well as to alter property of resonances in real time through stiffening of the spring constants, in addition to the PT symmetric

Canada Basin Acoustic Propagation Experiment (CANAPE)

Science.gov (United States)

2015-09-30

acoustic communications, acoustic navigation, or acoustic remote sensing of the ocean interior . RELATED PROJECTS The 2015 CANAPE pilot study was a...1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Canada Basin Acoustic Propagation Experiment (CANAPE...ocean structure. Changes in sea ice and the water column affect both acoustic propagation and ambient noise. This implies that what was learned

Transmission acoustic microscopy investigation

Science.gov (United States)

Maev, Roman; Kolosov, Oleg; Levin, Vadim; Lobkis, Oleg

The nature of acoustic contrast, i.e. the connection of the amplitude and phase of the output signal of the acoustic microscope with the local values of the acoustic parameters of the sample (density, elasticity, viscosity) is a central problem of acoustic microscopy. A considerable number of studies have been devoted to the formation of the output signal of the reflection scanning acoustic microscope. For the transmission acoustic microscope (TAM) this problem has remained almost unstudied. Experimental investigation of the confocal system of the TAM was carried out on an independently manufactured laboratory mockup of the TAM with the working frequency of the 420 MHz. Acoustic lenses with the radius of curvature of about 500 microns and aperture angle of 45 deg were polished out in the end faces of two cylindrical sound conductors made from Al2O3 single crystals with an axis parallel to the axis C of the crystal (the length of the sound conductor is 20 mm; diameter, 6 mm). At the end faces of the sound conductor, opposite to the lenses, CdS transducers with a diameter of 2 mm were disposed. The electric channel of the TAM provided a possibility for registering the amplitude of the microscope output signal in the case of the dynamic range of the 50 dB.

What Is an Acoustic Neuroma

Science.gov (United States)

... CALENDAR DONATE NEWS Home Learn Back Learn about acoustic neuroma AN Facts What is acoustic neuroma? Diagnosing ... Italian Japanese Korean Portuguese Romanian Spanish What is Acoustic Neuroma? Each heading slides to reveal information. Important ...

Biological aspects of Cirrospilus neotropicus Diez and Fidalgo (Hymenoptera: Eulophidae), parasitoid of Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae)

International Nuclear Information System (INIS)

Foelkel, Ester; Redaelli, Luiza R.; Jahnke, Simone M.; Losekann, Paula B.

2008-01-01

The biology of Cirrospilus neotropicus Diez and Fidalgo reared on third instar Phyllocnistis citrella Stainton larvae having Citrus limonia Osbeck as host plant, was evaluated under controlled conditions (25 ± 1 deg C; 12 h photophase). The survival, immature development, longevity, sex ratio, host feeding and oviposition ratio of C. neotropicus, were registered. Two groups of parasitoid females were evaluated: one, with parasitoids obtained from P. citrella pupae collected in citrus orchards and the other group came from laboratory rearing. These females, after mating, were maintained individually on gerbox containers with honey and pollen as food source. At each 48h, 12 P. citrella larvae were changed. The average biological cycle of the female progenies from orchard and laboratory generation groups were 11.8 and 11.6 days, respectively. The males progenies had biological cycles of 11.6 and 10.9 days, as well. The shortest immature survival period, for both studied groups was the larval (57.3% - orchard group and 57.4% - lab group). The mated females average longevity (21.8 days) was superior than the non mated ones (9.1 days) for the orchard group. The average daily oviposition rate for this last group was also significantly superior (2.8 eggs /day) than the lab group (1.6 eggs / day). The same trend was observed for the average daily host feeding rate (1.7 larvae /day for the orchard group and 0.9 larvae/ day for the lab group). These data suggest that C. neotropicus have potential as a biological control agent of P. citrella. (author)

Shallow-Water Mud Acoustics

Science.gov (United States)

2015-09-30

1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Shallow-Water Mud Acoustics William L. Siegmann...models and methods that explain observed material and acoustic properties of different physical types of shallow-ocean mud sediments. Other goals...are to assess prior data relating to the acoustic properties of mud and to provide guidance in the development and interpretation of experiments. A

Tutorial on architectural acoustics

Science.gov (United States)

Shaw, Neil; Talaske, Rick; Bistafa, Sylvio

2002-11-01

This tutorial is intended to provide an overview of current knowledge and practice in architectural acoustics. Topics covered will include basic concepts and history, acoustics of small rooms (small rooms for speech such as classrooms and meeting rooms, music studios, small critical listening spaces such as home theatres) and the acoustics of large rooms (larger assembly halls, auditoria, and performance halls).

Aphid-parasitoid community structure on genetically modified wheat.

Science.gov (United States)

von Burg, Simone; van Veen, Frank J F; Álvarez-Alfageme, Fernando; Romeis, Jörg

2011-06-23

Since the introduction of genetically modified (GM) plants, one of the main concerns has been their potential effect on non-target insects. Many studies have looked at GM plant effects on single non-target herbivore species or on simple herbivore-natural enemy food chains. Agro-ecosystems, however, are characterized by numerous insect species which are involved in complex interactions, forming food webs. In this study, we looked at transgenic disease-resistant wheat (Triticum aestivum) and its effect on aphid-parasitoid food webs. We hypothesized that the GM of the wheat lines directly or indirectly affect aphids and that these effects cascade up to change the structure of the associated food webs. Over 2 years, we studied different experimental wheat lines under semi-field conditions. We constructed quantitative food webs to compare their properties on GM lines with the properties on corresponding non-transgenic controls. We found significant effects of the different wheat lines on insect community structure up to the fourth trophic level. However, the observed effects were inconsistent between study years and the variation between wheat varieties was as big as between GM plants and their controls. This suggests that the impact of our powdery mildew-resistant GM wheat plants on food web structure may be negligible and potential ecological effects on non-target insects limited.

Micromachined silicon acoustic delay line with improved structural stability and acoustic directivity for real-time photoacoustic tomography

Science.gov (United States)

Cho, Young; Kumar, Akhil; Xu, Song; Zou, Jun

2017-03-01

Recent studies have shown that micromachined silicon acoustic delay lines can provide a promising solution to achieve real-time photoacoustic tomography without the need for complex transducer arrays and data acquisition electronics. However, as its length increases to provide longer delay time, the delay line becomes more vulnerable to structural instability due to reduced mechanical stiffness. In addition, the small cross-section area of the delay line results in a large acoustic acceptance angle and therefore poor directivity. To address these two issues, this paper reports the design, fabrication, and testing of a new silicon acoustic delay line enhanced with 3D printed polymer micro linker structures. First, mechanical deformation of the silicon acoustic delay line (with and without linker structures) under gravity was simulated by using finite element method. Second, the acoustic crosstalk and acoustic attenuation caused by the polymer micro linker structures were evaluated with both numerical simulation and ultrasound transmission testing. The result shows that the use of the polymer micro linker structures significantly improves the structural stability of the silicon acoustic delay lines without creating additional acoustic attenuation and crosstalk. In addition, a new tapered design for the input terminal of the delay line was also investigate to improve its acoustic directivity by reducing the acoustic acceptance angle. These two improvements are expected to provide an effective solution to eliminate current limitations on the achievable acoustic delay time and out-of-plane imaging resolution of micromachined silicon acoustic delay line arrays.

Handbook of Engineering Acoustics

CERN Document Server

Möser, Michael

2013-01-01

This book examines the physical background of engineering acoustics, focusing on empirically obtained engineering experience as well as on measurement techniques and engineering methods for prognostics. Its goal is not only to describe the state of art of engineering acoustics but also to give practical help to engineers in order to solve acoustic problems. It deals with the origin, the transmission and the methods of the abating different kinds of air-borne and structure-borne sounds caused by various mechanisms – from traffic to machinery and flow-induced sound. In addition the modern aspects of room and building acoustics, as well as psychoacoustics and active noise control, are covered.

Ion-acoustic plasma turbulence

International Nuclear Information System (INIS)

Bychenkov, V.Y.; Silin, V.P.

1982-01-01

A theory is developed of the nonlinear state that is established in a plasma as a result of development of ion-acoustic instability. Account is taken simultaneously of the linear induced scattering of the waves by the ions and of the quasilinear relaxation of the electrons by the ion-acoustic pulsations. The distribution of the ion-acoustic turbulence in frequency and in angle is obtained. An Ohm's law is established and expressions are obtained for the electronic heat flux and for the relaxation time of the electron temperature in a turbulent plasma. Anomalously large absorption and scattering of the electromagnetic waves by the ion-acoustic pulsations is predicted

A new definition for acoustic dose

International Nuclear Information System (INIS)

Duck, F A

2011-01-01

This paper discusses a recent proposal for definitions of acoustic dose and acoustic dose-rate. Acoustic dose is defined as the energy deposited by absorption of an acoustic wave per unit mass of the medium supporting the wave. Its time-derivative, acoustic dose-rate, Q m , in W kg -1 is central to the prediction of both rate of temperature rise and radiation force. These quantities have spatial and temporal dependency, depending on the local field parameters (acoustic pressure, particle velocity, intensity) and local material properties (absorption coefficient, α a , and mass density, ρ 0 ). Spatial and/or temporal averaging can be applied where appropriate. For plane-wave monochromatic conditions in a homogeneous medium, Q m =2α a I/ρ 0 , (I is the time-averaged intensity), a simple expression which may also incorporate frequency dependencies of energy deposition. Acoustic dose and acoustic does-rate are exact analogues for Specific Absorption and Specific Absorption Rate (SAR), quantities central to radiofrequency (RF) and microwave dosimetry. Acoustic dosimetry in the presence of tissue/gas interfaces remains a considerable challenge.

Fundamentals of Shallow Water Acoustics

CERN Document Server

Katsnelson, Boris; Lynch, James

2012-01-01

Shallow water acoustics (SWA), the study of how low and medium frequency sound propagates and scatters on the continental shelves of the world's oceans, has both technical interest and a large number of practical applications. Technically, shallow water poses an interesting medium for the study of acoustic scattering, inverse theory, and propagation physics in a complicated oceanic waveguide. Practically, shallow water acoustics has interest for geophysical exploration, marine mammal studies, and naval applications. Additionally, one notes the very interdisciplinary nature of shallow water acoustics, including acoustical physics, physical oceanography, marine geology, and marine biology. In this specialized volume, the authors, all of whom have extensive at-sea experience in U.S. and Russian research efforts, have tried to summarize the main experimental, theoretical, and computational results in shallow water acoustics, with an emphasis on providing physical insight into the topics presented.

The Development of the Acoustic Design of NASA Glenn Research Center's New Reverberant Acoustic Test Facility

Science.gov (United States)

Hughes, William O.; McNelis, Mark E.; Hozman, Aron D.; McNelis, Anne M.

2011-01-01

The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) is leading the design and build of the new world-class vibroacoustic test capabilities at the NASA GRC s Plum Brook Station in Sandusky, Ohio. Benham Companies, LLC is currently constructing modal, base-shake sine and reverberant acoustic test facilities to support the future testing needs of NASA s space exploration program. The large Reverberant Acoustic Test Facility (RATF) will be approximately 101,000 ft3 in volume and capable of achieving an empty chamber acoustic overall sound pressure level (OASPL) of 163 dB. This combination of size and acoustic power is unprecedented amongst the world s known active reverberant acoustic test facilities. The key to achieving the expected acoustic test spectra for a range of many NASA space flight environments in the RATF is the knowledge gained from a series of ground acoustic tests. Data was obtained from several NASA-sponsored test programs, including testing performed at the National Research Council of Canada s acoustic test facility in Ottawa, Ontario, Canada, and at the Redstone Technical Test Center acoustic test facility in Huntsville, Alabama. The majority of these tests were performed to characterize the acoustic performance of the modulators (noise generators) and representative horns that would be required to meet the desired spectra, as well as to evaluate possible supplemental gas jet noise sources. The knowledge obtained in each of these test programs enabled the design of the RATF sound generation system to confidently advance to its final acoustic design and subsequent on-going construction.

Select Internet Resources on Acoustics

Directory of Open Access Journals (Sweden)

Angela R. Davis

2016-12-01

Full Text Available Merriam-Webster (2016 defines acoustics as, “a science that deals with the production, control, transmission, reception, and effects of sounds.” According to Rossing (2014, the study of acoustics began in ancient Greece with Pythagoras’ study of vibrating strings on musical instruments. Since those early beginnings, famous scientists including Rayleigh, Alexander Graham Bell, and Thomas Edison, have helped expand the field of acoustics to include architectural, physical, engineering, structural, underwater, physiological and psychological, musical acoustics, and speech. Acoustics is a highly interdisciplinary field and researchers may need resources from physics, medicine, and engineering to understand all aspects of their research.