Foraging and Oviposition Decisions in the Parasitoid Aphytis lingnanensis: Distinguishing the Influences of Egg Load and Experience

Abstract

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Oviposition behavior of wild Zabrotes subfasciatus (Coleoptera, Chrysomelidae) females deprived of the host Phaseolus vulgaris (Fabaceae)

“…These inferences are in agreement with the study of ROSENHEIM & ROSEN (1991), who observed that the load of eggs influenced the intensity of the search behavior in the A. lingnanensis parasitoids, since the females with smaller load of eggs needed more time inside a foraging area to discover the host.…”

“…Notwithstanding, ROSENHEIM & ROSEN (1991) shows that the manipulation period with the host was inversely related to the load of eggs in the parasitoid A. lingnanensis, as well as of each component of the activities that comprise host manipulation, including preparation for oviposition, post-oviposition period, grooming and rest.…”

“…The studies about host deprivation and others closely associated studies have, in general, revealed increased amplitude in the variation of hosts and/or increased size of the aggregate, in response to deprivation and/or increased load of eggs (ROSENHEIM & ROSEN, 1991).…”

“…They concentrated oviposition in the 1 st seed that they found at 29° C and 70 % R. H. (SPERANDIO & ZUCOLOTO, 2004). ROSENHEIM & ROSEN (1991) also observed that in the A. lingnanensis parasitoid, the females with larger loads of eggs laid larger aggregates. Those observations are also in agreement with MINKENBERG et al (1992) and ALUJA et al (2001) that also observed that the load of eggs influences the size of the female aggregate at 26° C temperature and 59-72 % R. H.…”

“…A delay to find an adequate host probably limits the available time for oviposition and can result in physiological changes (ASMAN & EKBOM, 2006); this can have consequences on the insect fecundity (TAMMARU & JAVOIS, 2000). ROSENHEIM & ROSEN (1991) observed that when the parasitoids A. lingnanensis had a previous contact experience with the host, they laid aggregates of smaller sizes. This agrees with this study observations, where deprived females laid higher amounts of aggregated eggs in relation to the control females (in all moments of deprivation) (pers.…”