Cover crops and rootstocks interaction on vine performances of organic ‘Autumn Pearl’ table grape: first results of OLTRE.BIO research project

Inter-row cover crops in organic viticulture are oriented to increase the biodiversity of soil and to promote healthy root status. The use of rootstocks on table grape cultivars is required due to phylloxera, nematodes, or soil difficulties, like high lime or salt content, drought and high groundwater conditions. The research was carried out in the Apulia region, in 2021 to determine the impact of two rootstocks (1103 Paulsen and 140 Ruggeri) on-field performance of organic ‘Autumn Pearl’ seedless vines grown on two different cover crops. The first one was a commercial mixture of grass cover and the second one a commercial grass-legume cover crop. ‘Autumn Pearl’ vines have shown the highest berry weight, equatorial diameter, and total soluble solid onto 140 Ruggeri and on grass cover crop. According to our data, grapevines onto 140 Ruggeri rootstock exhibited the highest photosynthetic assimilation rate and leaf transpiration. The use of inter-row cover crops (permanent or temporary) in viticulture has many advantages, of which the reduction of water runoff and soil erosion, restriction of evaporation from the soil surface, improvement of soil water holding and soil organic matter, the reduction of temperature fluctuations in the soil, as well as the regulation of the vine growth and vigor, with influence on table grape quality and quantity.