Successful controlling of Lobesia botrana (Lepidoptera: Tortricidae), using meso-dispensers for mating disruption in urban areas

Abstract

The European grapevine moth (EGVM), Lobesia botrana (Denis & Schiffermüller), is a severe pest of grapes, since detected in Chile in 2008 has been subjected to an official control program by the Chilean Department of Agriculture, mainly in vineyards and orchards. Lobesia botrana has also been found in urban areas, mostly on backyard grapes, those have become important refuges for large L. botrana populations and significant sources for both dispersal and re-infestation to agricultural settings, thus the need for control. Chemical sprays are not allowed for intensive pest management in residential areas; therefore, the mating disruption technique has been the main tool to control L. botrana in cities. However, it is not always feasible to evenly deploy the required amount of dispenser ha -1 in urban areas using conventional formulations. A new meso-dispenser (MeD), loaded with 10x the regular amount of pheromone of standard dispensers, and recommended at 50 units ha -1 , was evaluated in three consecutive seasons (2013-2016), in four cities in central Chile. This new dispenser yielded significantly lower male captures in traps in comparison with untreated areas. Cumulative male captures per individual flights per season, ranged between 292-2043 trap -1 (MeD) and 15 795-28 403 trap -1 (untreated), and significantly declined in the second and third seasons of MeD usage. Disruption index ranged between 68.9% and 98.9% considering flights individually, and above 88.0% considering whole seasons. The presence of eggs, larvae, and pupae infesting clusters, also significantly declined with the number of seasons treated with MeD.