Under-vine cover crops in viticulture: impact of different weed management practices on weed suppression, yield and quality of grapevine cultivar Riesling

Abstract

The regulation of weeds, particularly in the under-vine area of grapevines, is essential for the maintenance of grape yield and quality. This is achieved primarily through herbicide application or mechanical tillage. However, the use of herbicides is controversial due to potential environmental and human health impacts (VAN BRUGGEN et al. 2021). Mechanical tillage represents an alternative that can be employed in organic vineyards. This method also presents certain disadvantages, especially in regard to soil erosion potential, the risk of damage to the vines, inconsistent efficiency and the associated costs for energy, machinery and labour. Given these challenges, alternative, sustainable approaches to weed management are essential for modern viticulture.

The implementation of cover crops in the under-vine zone has been demonstrated to be an effective method for weed regulation, which simultaneously results in improvements in soil structure and soil temperature (ABAD et al. 2023). However, the impact of this approach on soil moisture levels remains relatively unclear (BAVOUGIAN & READ 2018). In terms of grape vine performance, a reduction in growth and yield has been evidenced (CHOU et al. 2018; CONIBERTI et al. 2018), as well as an increase in root length density at deeper soil layers (FLEISHMAN et al. 2023). A reduction in vigor and deeper roots of grapevine, as well as the impact on soil health, could lead to greater resilience in viticulture.

In order to benefit from the positive aspects of under-vine cover crops, it is essential to select appropriate plant species and establish them effectively. This research project was therefore initiated to address the limited number of studies on under-vine cover crops in European viticulture in non-irrigated vineyards with cool climate conditions. Furthermore, there is a need to explore the impact of different plant species, beyond the potential cost savings offered by perennial cover crops, which also possess ecological advantages.