title: Cumulative effects of volcanic ash on the food preferences of two Orthopteran species.
abstract: Inert dusts are an early form of insecticide which is still in use. One of the most common inert dusts is volcanic ash. In order to study the reaction of rangeland grasshoppers, Dichroplus vittigerum (Acrididae) and a katydid, Burgilis mendosensis (Phaneropteridae), to the presence of volcanic ash in their food sources and how this reaction changed as a function of time, we conducted paired preference tests between clean leaves of their preferred host plant and leaves exposed to volcanic ash of different grain size. The behavioral response was measured as the rating on the Thurstonian preference scale of leaves with ash in relation to clean leaves. The results showed that the avoidance of volcanic ash increased as a function of time in both species. Both species studied are occasionally exposed to volcanic activity, and come from an area in which a volcanic eruption had recently occurred. As their populations did not decrease after the ash fall, we propose that some behavioral responses such as avoidance of places with ash, works as tolerance mechanism to inert dusts exposure.
authors.affiliation: Instituto Nacional de Tecnología Agropecuaria, Estación Experimental Agropecuaria-Bariloche, CC277, Av, Modesta Victoria 4450 (8400), San Carlos de Bariloche, Argentina.|Centro Científico Tecnológico - Consejo Nacional de Investigaciones Científicas y Técnicas (CCT-CONICET) Patagonia Norte. Av. de los Pioneros 2350, San Carlos de Bariloche, Río Negro, Argentina.
authors.forename: Valeria
authors.initials: V
authors.lastname: Fernández-Arhex
authors.affiliation: Lab, ECOTONO-INIBIOMA, Pje. Gutierrez 850, San Carlos de Bariloche, Río Negro, Argentina.|Centro Científico Tecnológico - Consejo Nacional de Investigaciones Científicas y Técnicas (CCT-CONICET) Patagonia Norte. Av. de los Pioneros 2350, San Carlos de Bariloche, Río Negro, Argentina.
authors.forename: Maria E
authors.initials: ME
authors.lastname: Amadio
authors.affiliation: Instituto Nacional de Tecnología Agropecuaria, Estación Experimental Agropecuaria-Bariloche, CC277, Av, Modesta Victoria 4450 (8400), San Carlos de Bariloche, Argentina.|Centro Científico Tecnológico - Consejo Nacional de Investigaciones Científicas y Técnicas (CCT-CONICET) Patagonia Norte. Av. de los Pioneros 2350, San Carlos de Bariloche, Río Negro, Argentina.
authors.forename: Octavio A
authors.initials: OA
authors.lastname: Bruzzone
mesh_terms: D000818:Animals; D001118:Argentina; D005518:Food Preferences; D006110:Grasshoppers / Q000502:physiology*; D010316:Particle Size; D018515:Plant Leaves; D029622:Portulacaceae; D031205:Taraxacum; D013997:Time Factors; D018707:Volcanic Eruptions / Q000009:adverse effects*
keywords: Burgilis mendosensis; Dichroplus vittigerum; inert dust; preference test; thurstone scale