Abundance, distribution, and associated forage losses of pest grasshoppers (Orthoptera: Acrididae) in the Argentine Pampas.

MARIOTTINI YANINA; MANCINI MICAELA; TROFINO CLARA; DE WYSIECKI MARIA LAURA; LANGE CARLOS

ANAIS DA ACADEMIA BRASILEIRA DE CIENCIAS.

ACAD BRASILEIRA DE CIENCIAS

Lugar: Rio de Janeiro; Año: 2023 vol. 95 p. 1 - 12

0001-3765

The goal of this study was to assess the status of Dichroplus elongatus and Borelliabruneri as actual agricultural pests in the Argentine Pampas by determining theirabundance, distribution, and associated forage loss. The study was conducted in Lapridaand Tandil, two counties in Buenos Aires province. In each county 20 sampling sites wereestablished and monitored from 2012 to 2018. B. bruneri was more abundant and with awider distribution in Laprida (91.4% of the sites) than in Tandil (42.1% of the sites) whileD. elongatus abundance was significantly higher from 2012 to 2016 in Tandil than inLaprida and its distribution was wide in Laprida (75% of the sites) and very wide in Tandil(77.14%). Under field-cage conditions forage loss caused at three different densities (8,16, and 32 ind/m2) of D. elongatus and B. bruneri adults on a pasture of Festucaarundinacea was estimated. Forage loss caused by D. elongatus was significantly higherthan that caused by B. bruneri. D. elongatus caused a significant decrease in biomass atthe three densities respect to the control, while B. bruneri only caused a significantdecrease at the highest density. Our study suggests that although the gomphocerine B.bruneri is an abundant and widely-distributed species capable of doing some damage inthe grasslands of the southern Pampas, it is comparatively much less harmful than themelanopline D. elongatus.