Search results for "Scelionid"
showing 9 items of 29 documents
Kairomonal effect of walking traces from Euschistus heros (Heteroptera: Pentatomidae) on two strains of Telenomus podisi (Hymenoptera: Scelionidae)
2003
. The semiochemical cues used by geographically isolated strains of the parasitoid, Telenomus podisi (Ashmed), to find eggs of the stink bug Euschistus heros were investigated. Two strains of Te. podisi, maintained on eggs of a South American host (E. heros) were studied. One parasitoid strain originated from specimens collected near Brasilia, Brazil (SA strain), and a second strain originated from specimens collected at Beltsville, Maryland (NA strain). Cold tolerance tests of adults from the NA and SA Te. podisi strains, analyses of the cuticular hydrocarbons between the two strains, and crossing experiments between strains each indicated consistent differences between the NA and SA stra…
Source of the host marking pheromone in the egg parasitoid Trissolcus basalis (Hymenoptera: Scelionidae).
2001
After oviposition, Trissolcus basalis females always mark the host's surface, depositing host marking substances for herself and to warn other ovipositing females. The perception of these host marking substances, probably through the antennae, can induce the female to leave and seek healthy hosts. Parasitoid females exposed to conspecific parasitized egg masses left the host egg masses significantly more often than when exposed to non-parasitized egg masses. More egg mass leaving behavior also was observed when the egg masses were treated with Dufour's gland secretion but not when treated with secretion from the common oviducts. The common oviduct has a secretory epithelium that produces el…
A New Species ofTelenomusHaliday (Hymenoptera: Scelionidae) Associated with Egg Batches of the Pine Processionary Moth,Thaumetopoea pityocampa(Dennis…
2009
Telenomus thaumetopoeae Buhl sp. n. is described from northeastern València (Peninsular Spain) taking as starting point females parasitizing the egg-batches of the Pine Processionary Moth, Thaumetopoea pityocampa (Dennis et Schiffermüller, 1775). Its morphological affinities with the most closely related species and parasitism data are offered.
Volatile and contact chemicals released by Nezara viridula (Heteroptera: Pentatomidae) have a kairomonal effect on the egg parasitoid Trissolcus basa…
1999
The responses of females of the egg parasitoid Trissolcus basalis (Wollaston) (Hymenoptera: Scelionidae) to volatile and contact chemicals from its host Nezara viridula (L.) (Heteroptera: Pentatomidae) were investigated in a Y-tube olfactometer and under open arena conditions. In the Y-tube tests, volatiles from virgin males and from females in a preovipositional state attracted T. basalis females, while volatiles from host virgin females did not. In an open arena, traces left by N. viridula adults in different physiological conditions function as contact cues inducing the wasps to remain longer in the arena and to change the pattern of their walking behavior. However, only contact kairomon…
Insect oviposition induces volatile emission in herbaceous plants that attracts egg parasitoid
2003
SUMMARYThe egg parasitoid Trissolcus basalis (Wollaston) (Hymenoptera:Scelionidae) responded to synomones emitted by leguminous plants induced by feeding and oviposition activity of the bug Nezara viridula (L.)(Heteroptera: Pentatomidae). This was shown by laboratory bioassays using a Y-tube olfactometer. Broad bean leaves (Vicia faba L.) damaged by feeding activity of N. viridula and on which host egg mass had been laid produced synomones that attracted T. basalis. By contrast,undamaged leaves or feeding-damaged leaves without eggs did not attract wasp females. French bean plants (Phaseolus vulgaris L.) also emitted attractive synomones when they were damaged by host feeding and carrying e…
Chemical Ecology of Egg Parasitoids Associated with True Bugs
2012
Parasitoids representing some 15 families of Hymenoptera develop in insect eggs; three of these families, Platygastridae (= Scelionidae), Mymaridae, and Encyrtidae, are associated with Heteroptera. Several species of heteropteran egg parasitoids are or may be important for biological pest control. Successful parasitism of insect herbivores by insect parasitoids arises through several phases of host searching, which lead female wasps to the vicinity of, or in contact with, their hosts. During the host location process, females encounter and explore a variety of stimuli, among which chemical cues (i.e., semiochemicals or infochemicals) play a pivotal role. Female parasitoids are under selecti…
Inter and intra-guild interactions in egg parasitoid species of the soybean stink bug complex
2002
Abstract – The objective of this research was to evaluate the parasitism behavior of Telenomus podisiAshmead, Trissolcus basalis (Wollaston) e Trissolcus urichi Crawford (Hymenoptera: Scelionidae) oneggs of Nezara viridula L., Euschistus heros F., Piezodorus guildinii Westwood and Acrosternumaseadum Rolston (Heteroptera: Pentatomidae), in no choice and multiple choice experiments. For allparasitoid species, the results demonstrated the existence of a main host species that maximizes thereproductive success. The competitive interactions among the parasitoid species were investigated inexperiments of sequential and simultaneous release of different combinations of parasitoid pairs on thehosts…
The ovipositing female of Ooencyrtus telenomicida relies on physiological mechanisms to mediate intrinsic competition with Trissolcus basalis
2012
Ongoing studies by our group showed that the outcome of the intrinsic competition between two solitary egg parasitoids, Trissolcus basalis (Wollaston) (Hymenoptera: Scelionidae) and Ooencyrtus telenomicida (Vassiliev) (Hymenoptera: Encyrtidae), is dominated by O. telenomicida. In this article we investigated the role played by the ovipositing O. telenomicida female in the suppression of a T. basalis competitor. Laboratory experiments were conducted by allowing an O. telenomicida female to puncture the eggs of Nezara viridula (L.) (Heteroptera: Pentatomidae) with her ovipositor (= no oviposition) or to parasitize them. The results show that O. telenomicida relies on some physiological mechan…
Host Searching by Egg Parasitoids: Exploitation of Host Chemical Cues
2010
Insect parasitoids are considered “keystone species” in many ecosystems in terms of biodiversity, ecological impact and economic importance (Vinson 1985, LaSalle and Gauld 1993, Hawkins et al. 1999). In the last decades, several reviews have been published on the relationships among plants, hosts and parasitoids, which reflect a strong interest in these insects both as models for behavioral ecologists and as important organisms for classical and applied biological control programs (Hawkins et al. 1999, Vet 1999, Bale et al. 2008). The majority of these studies have considered the larval parasitoid s, besides the extensive use of egg parasitoids in biological control (Hawkins et al. 1999). I…