Influence of soil type and changes in soil solution chemistry on vine growth parameters and grape and wine quality in a central coast California vineyard

Grapevine vigour, defined as the propensity to assimilate, store and/or use non-structural sugars for allowing fast growth of shoots and producing large canopies[1], is crucial to optimize vineyard management. Recently, a model has been proposed for predicting the vigor of young grapevines through the measurement of the vegetative growth and physiological parameters, such as water status and gas exchange[2]. Our objectives were (1) to explore the influence of the association of two grapevine varieties (Tempranillo and Cabernet Sauvignon, grafted onto R110 rootstocks) with arbuscular mycorrhizal fungi (AMF) on the vegetative vigour of young plants; and (2) to assess the effect of environmental factors linked to climate change on the vegetative vigour of Cabernet Sauvignon.

The geology of a region is deemed to be an important component of terroir, as it influences the shape of the landscape and the climate of vineyard. The nature of rock and the geomorphological history of a terroir affect soil physical and chemical composition through a dynamic interplay with the changes of climate, vegetation and other living organisms, as well as with man activities.

It is widely known the impact that oxidation has on wine sensory degradation and eventually, in the shortening of its longevity.

On the market there are several wine grapes which are tolerant to the main fungal diseases. These varieties, commonly defined “resistant”, were developed in the grapevine breeding programs carried out mainly in Germany, France, Hungary and Italy. Some of these cultivars have been included in the national catalogues of wine grape varieties and have sometimes been allowed for specific kinds of wine. The VEVIR project, aimed at the enological evaluation of resistant vines, involves 33 cultivars achieved at the State Institute for Viticulture Freiburg in Germany, the Research Institute of Viticulture and Enology Pecs in Hungary and the Fondazione Edmund Mach S. Michele all’Adige (FEM) in Italy.

The phenological stage of the grapevine (Vitis vinifera L.) represents a fundamental element in vineyard management, since it determines key practices such as fertilization, irrigation, phytosanitary interventions and optimal harvest time (Mullins et al., 1992).