Search results for "Trissolcus basali"

Thermal stress affects patch time allocation by preventing forgetting in a parasitoid wasp

2015

Learning and memory allow animals to adjust their foraging strategies through experience. Despite the known impact of temperature on many aspects of the behavioral ecology of animals, memory retention in the face of realistic thermal stress has seldom been assessed. In the laboratory, we studied the behavioral expression of an egg parasitoid’s (Trissolcus basalis) memory when exposed to thermal stress that could be encountered in nature. We hypothesized that thermal stress would disrupt memory consolidation and/ or modify the optimality of memory retention, thus affecting patch time allocation strategies. Memory consolidation was resilient to 1 h of thermal stress following an unrewarded ex…

Contrasting reproductive traits of competing parasitoids facilitate coexistence on a shared host pest in a biological control perspective

2022

BACKGROUND: Interspecific competition in insect parasitoids is an important ecological phenomenon that has relevant implications for biological pest control. To date, interspecific intrinsic (=larval) competition has been intensively studied, while investigations on extrinsic (=adult) competition have often lagged behind. In this study we examined the role played by parasitoid reproductive traits and host clutch size on the outcome of extrinsic competition between Trissolcus basalis (Wollaston) and Ooencyrtus telenomicida (Vassiliev), two egg parasitoids of the pest Nezara viridula (L). Laboratory experiments were conducted by allowing both parasitoid species to exploit an egg mass made of …

Effect of host kairomones and oviposition experience on the arrestment behavior of an egg parasitoid

2006

SUMMARY Chemical residues left by walking adults of the southern green stink bug, Nezara viridula (L.) (Heteroptera: Pentatomidae) induce arrestment behavior in the egg parasitoid Trissolcus basalis (Wollaston)(Hymenoptera: Scelionidae) leading to prolonged periods of walking on contaminated areas and to systematic return to the stimulus after encountering the treatment borders. In this study, we quantified how the hierarchical value of residues from host adults and oviposition experience can influence the arrestment behavior of T. basalis females. Our results showed that:(1) female wasps perceived host residues at different hierarchical levels depending on the host gender, with a clear pre…

Host sex discrimination by an egg parasitoid on Brassica leaves.

2011

Egg parasitoids are able to find their hosts by exploiting their chemical footprints as host location cues. In nature, the apolar epicuticular wax layer of plants that consists of several classes of hydrocarbons serves as the substrate that retains these contact kairomones. However, experiments on chemical footprints generally have used filter paper as substrate to study insect behavior. Here, we explored the ability of Trissolcus basalis (Scelionidae) females to discriminate between footprint cues left by male and female Nezara viridula (Pentatomidae) on leaves of their host plant Brassica oleracea (broccoli). Furthermore, we analyzed the chemical composition of the outermost wax layer of …

The Egg Parasitoid Trissolcus basalis uses n-nonadecane, a Cuticular Hydrocarbon from its Stink Bug Host Nezara viridula, to Discriminate Between Fem…

2007

Contact kairomones from adult southern green stink bugs, Nezara viridula (L.) (Heteroptera: Pentatomidae) that elicit foraging behavior of the egg parasitoid Trissolcus basalis (Wollaston) were investigated in laboratory experiments. Chemical residues from tarsi and scutella of N. viridula induced foraging by gravid female T. basalis. Residues from body parts of female N. viridula elicited stronger responses than those from the corresponding body parts of males. Deproteinized tarsi still elicited searching responses from wasps, indicating that the kairomone was not proteinaceous. Hexane extracts of host cuticular lipids induced searching responses from T. basalis, with a strong preference f…

Intraguild interaction between egg parasitoids: the role of the host egg mass size and parasitoids’ reproductive capacities

2013

In Sicily, field collections of egg masses of the southern green stink bug, Nezara viridula (L.) (Heteroptera:Pentatomidae), revealed that two solitary parasitoids, Trissolcus basalis (Wollaston) (Hymenoptera: Platygastridae) and Ooencyrtus telenomicida (Vassiliev) (Hymenoptera: Encyrtidae), can exploit the same egg mass. Previous finding showed that parasitoid species differ in host location and larval competitive abilities and a host finding-larval competition trade-off may be important for coexistence. The aim of this work was to evaluate the role played by the host egg mass size and the importance of species reproductive capacities in the outcome of interspecific competition. Under labo…

Nectar-Inhabiting Bacteria Affect Olfactory Responses of an Insect Parasitoid by Altering Nectar Odors

2022

AbstractFloral nectar is ubiquitously colonized by a variety of microorganisms among which yeasts and bacteria are the most common. Microorganisms inhabiting floral nectar can alter several nectar traits, including nectar odor by producing microbial volatile organic compounds (mVOCs). Evidence showing that mVOCs can affect the foraging behavior of insect pollinators is increasing in the literature, whereas the role of mVOCs in altering the foraging behavior of third-trophic level organisms such as insect parasitoids is largely overlooked. Parasitoids are frequent visitors of flowers and are well known to feed on nectar. In this study, we isolated bacteria inhabiting floral nectar of buckwhe…

The role of chemical cues in the host finding behaviour of Trissolcus basalis from a Conservation Biological Control perspective

In assessing successful biological control programs by parasitoids, the knowledge of important traits, such as the host finding capability, i.e. the ability to find host and food resources, play the key role. Moreover, parasitoids in their natural environment parasitoids deal with a variable mixtures of natural cues. Some chemical cues are used by the wasps to locate their hosts, some ones drive wasps to feeding resources. The parasitoid response to these cues can fluctuate according to biotic factors and abiotic condition. This dissertation focus in details on the role of two important tools, such as selective flowering plants as food resources to add within a crop area and the traces left…

Effetto della localizzazione dello stress biotico sulle difese indotte in Vicia faba

2016

Le diverse fasi che caratterizzano l’attacco della pianta da parte del fitofago (contatto, alimentazione ed ovideposizione) inducono l’attivazione di meccanismi di difesa nell’ospite. E’ noto che le piante emettono composti volatili indotti in seguito all’attacco del fitofago e che questi volatili sono in grado di richiamare i parassitoidi. Nel caso specifico degli ooparassitoidi, tali difese indirette si esplicitano mediante rilascio di HIPV (herbivore-induced plant volatiles) ed in particolare di OIPV (oviposition-induced plant volatiles). Ad oggi non ci sono studi inerenti il ruolo giocato dalle tracce rilasciate dal fitofago sulla superficie vegetale nell’induzione di volatili utilizzat…

Impact of an invasive pest in local semiochemical networks

During the host location process, egg parasitoids rely on a series of chemical stimuli from the host/plant complex. In particular, in tritrophic systems consisting of plants, herbivorous stink bugs and their egg parasitoids, previous studies demonstrated that wasps are attracted by oviposition-induced plant volatiles (OIPVs). These compounds act as indirect plant defence mechanism allowing plants to recruit egg parasitoids, which are in general the most important natural enemies of stink bugs. Moreover, when wasps land on a plant, they can exploit chemical footprints left by male and female stink bugs walking on the leaves as indirect host-related cues, since chemicals lead them in an area …