Cover crops in the inter-row of a table grape vineyard managed with irrigation sensors: Effects on yield, quality and glutamine synthetase activity in leaves

Researchers, farmers and viticulturists have focused on the development and adoption of alternative management strategies that are more environmentally and economically sustainable. One strategy could be cover crops, which are often sowed as a mix of non-leguminous and leguminous species, with positive effects on nitrogen nutrition of the vines. Irrigation of cover cropped vineyards can be managed with the use of wireless soil sensors. Nitrogen (N) is the most important soil mineral nutrient for plant growth and glutamine synthetase (GS) is not only responsible for N assimilation, but is also involved in different responses to both biotic or abiotic stresses. Therefore, the aims of this this study were to determine the effects of two different soil management practices (cover crops and tillage) on the vegetative activity of Italia table grape, as well as on fruit yield and quality and on the GS enzyme activity at different phenological stages of the grapevine. White clover reduced the canopy of Italia vines but increased the GS activity; no effects were reported for yield and quality of harvested clusters.