Response of the parasitoidTelenomus podisito induced volatiles from soybean damaged by stink bug herbivory and oviposition

Abstract

Egg parasitoids have a short time frame in which their host eggs are suitable for parasitism, and in several systems these parasitoids respond to plant volatiles induced by oviposition on the plant (either in isolation or in combination with feeding damage) as a means of finding suitable hosts. It is known that the parasitoid of pentatomid eggs Telenomus podisi responds to damage done to soybeans by female Euschistus heros, its preferred host. In this study our aim was to determine the type of E. heros damage to soybean (herbivory, oviposition or a combination of both) necessary for attraction of T. podisi. In a Y-tube olfactometer the parasitoid has shown to respond to the undamaged plant over clean air and herbivory-damaged plants over undamaged plants. However, the parasitoids did not respond to the treatments where oviposition occurred, either in isolation or in combination with herbivory. Analysis of volatile blends revealed that herbivory plus oviposition damage to soybean induced a volatile blend different to those induced when herbivory or oviposition occurred separately. These results, along with other results from this system, suggest that T. podisi uses plant volatile cues associated with female E. heros damage in order to be present when E. heros lays its eggs, and thus ensure its resource is optimal for parasitism.

Egg parasitoid wasps as natural enemies of the neotropical stink bug Dichelops melacanthus

“…The parasitoids showed a differential ability to identify and use D. melacanthus eggs as a suitable host, and the proportion of parasitism reported here, for some of the species, showed differences with the parasitism previously reported in other hosts (Pacheco & Corrêa-Ferreira, 1998;Sujii et al, 2002;Laumann et al, 2008). Nevertheless, the present work corroborates previous observations for different species of Scelionidae (Kivan & Kilic, 2002, indicating that, despite being oligophagous or polyphagous (Austin et al, 2005) (Figure 1).…”

“…basalis (Colazza et al, 2004) or Te. podisi (Moraes et al, 2005(Moraes et al, , 2008. In addition, there is also some evidence that these parasitoids may selectively respond to semiochemicals from stink bugs (Borges et al, 2003;Conti et al, 2004;Salerno et al, 2006;Silva et al, 2006;Laumann et al, 2009) or substrate-borne vibratory signals used in the stink bug sexual communication (Laumann et al, 2007 complexes in tri-trophic interactions, as well as other relevant biological and ecological aspects need to be established.…”

“…These parasitoid wasps have biological attributes and behavioral responses to host density that could lead to density-dependent parasitism and efficient local regulation of stink bug populations (Laumann et al, 2008). In Brazil, Corrêa-Ferreira & Moscardi (1996) showed that inoculative liberation of Tr.…”

The chemical volatiles (Semiochemicals) produced by neotropical stink bugs (Hemiptera: Pentatomidae)

“…This compound has been tested in bioassays using a Y-tube olfactometer and in the fi eld (Peres 2004;Laumann et al, unpublished). However (E)-2-hexenal is a common plant volatile, and is produced in large amounts by soybean, a major host plant for E. heros (Moraes et al 2008a). Thus it is not yet possible to determine whether the parasitoid responds to this compound as a cue directly associated to their host or as a means of fi nding the habitat of their host.…”

Chemical Ecology Studies in Soybean Crop in Brazil and Their Application to Pest Management

“…Once the parasitoid is within a potential host community, shape and semivolatile factors increase in importance and when the host is contacted, contact chemicals, shape, size and texture then become important (Vinson, 1984). Scelionidae that parasitize eggs from stink bugs can use several types of semiochemicals for long-range localization of habitat, microhabitat, and hosts: volatiles from plants damaged by stink bug oviposition or feeding Moraes et al, 2005cMoraes et al, , 2008c; sex pheromones (Aldrich, 1995;Borges et al, 1998a,b;2003, Bruni et al, 2000Silva et al, 2006); volatile defensive secretions from the metathoracic (adults) or dorsal abdominal (nymphs) glands of stink bugs (Aldrich 1995, Mattiacci et al, 1993Borges & Aldrich 1992); or crude whole body extracts of stink bugs (Colazza et al 1999;Salerno et al 2006). Volatiles from non-host stages of stink bugs, such as pheromones or defensive compounds, as well as contact chemicals (traces left by walking insects) can also be used for host location, recognition, and acceptance leading to successful oviposition Borges et al, 1999bBorges et al, , 2003Colazza et al, 1999;Conti et al 2003).…”