Search results for "egg parasitoid"
showing 3 items of 23 documents
INTRAGUILD INTERACTIONS BETWEEN EGG PARASITOIDS: FROM LABORATORY TO FIELD INVESTIGATIONS
Field studies on egg parasitoid guilds of herbivore stink bugs, serious pests for a wide number of crops, have shown that Trissolcus spp. and Ooencyrtus spp. can naturally co-occur in the same host, and generally the former parasitize more eggs than the latter. In many countries, to control such pests, biological control programs based on egg parasitoids have been used obtaining inconstantly success. Thereby, understanding the competitive interactions among Trissolcus and Ooencyrtus species may be useful in order to improve biological control of such pests but only few researchers have investigated the effects of competitive interactions among these egg parasitoids. The aim of this thesis w…
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…
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…