Current challenges of the grape berry moth (Lobesia botrana) in the Douro Demarcated Region

OBJECTIVE

Considering the guidelines of Directive 2009/128/EC for the sustainable use of pesticides, the implementation of protection strategies against Lobesia botrana (Denis & Schiffmüller), is a fundamental practice for a more sustainable viticulture. The method of protection by mating disruption and monitoring with pheromone traps has been tested in the Douro Wine Region (DWR). This method consists of disrupting mating, through the saturation of the atmosphere with a synthetic sexual pheromone (E,Z-7,9- dodecadienyl acetate) released by diffusers placed in grapevines. The NOVATERRA project aims at evaluating the effectiveness of an innovative passive pheromone diffusion system.

SUMMARY

The grape berry moth, L. botrana is considered the main grapevine pest in several countries in Southern Europe, causing direct damage caused by the caterpillar, as well as indirect damage by promoting the installation of fungal diseases, such as gray rot caused by Botrytis cinerea. Due to the critical economic importance of the grape crop in the DWR in Portugal, this pest can cause notable losses due to the negative effect on the quality of grapes

and resulting wine. In DWR, L. botrana can develop three to four generations per year which can affect up to 50% of the bunches at harvest.

In this sense, the development of means capable of ensuring effective protection from this pest has deserved special attention on the part of the scientific community. The novel method of passive diffusion of protection against the grape berry moth, developed by partner CORTEVATM, consists of pheromone application under gel form (Press Enrapta Lobesia) on the grapevine’s bark, which is biodegradable once the pheromone release is over (Figure 1). Trials were carried out at vineyards in Quinta do Seixo (property of Sogrape, DWR – Portugal) and damage assessments were done after each pest generation and at harvest (Figure 2). Results indicate there are no significant differences in the performance of the new formulation and the standard diffusion method (ISONET L TT, generating a plastic residue), while both methods show significant protection improvements when compared to the untreated area which presented with a higher percentage of damaged bunches.