USING COVER CROPS TO CONTROL LOBESIA BOTRANA IN ORGANIC VINEYARDS

Abstract

This work aim to develop new viticultural systems based on increased plant diversity within vineyards intending to plant cover crops species with repulsiv or insecticide effects for the control of the grapevine moth (Lobesia botrana). Lobesia botrana is a major pest in European vineyards that can cause economic damages. SCV identified six potential candidates to repel L. botrana from grapes. In autumn 2018, SCV prepared extracts of these plant species and provided them to Agroscope. Over the winter, Agroscope tested the efficacy of these plant extracts in the laboratory. The tested extracts had neither a strong effect on the survival of L. botrana larvae, nor did they repel larvae from feeding. However, three of these extracts repelled L. botrana females from egg laying. Considering these results obtained by Agroscope, these plant extracts were prepared and tested by SCV in 2019. In an experimental vineyard in Murfatlar (Romania), the three extracts were applied either on their own or in a mixture of all three together at the ripening phase (BBCH 83-85). Pheromone traps were used to observe the impact on the adult pest population of L. botrana. Treatments in which the Artemisia absinthium extract was applied on its own or in the mixture recorded the smallest number of adults. Moreover, only 0.25% of grapes where infested by L. botrana in the mixture treatment compared to 3.8% of clusters in the treatment with the Tagetes sp. extract. We therefore conclude that the mixture of Artemisia absinthium, Tagetes sp. and Allium sativum might have an interesting potential to protect grapes against L. botrana infestation.