Organic mulches improve vine vigour, yield and physiological response in a semi-arid region

Field-grown crops such as grapevines, rely on ambient environmental conditions for growth and development.

High-volume mass-market white wines production method by means of harvest-deferred fermentation from desulphited musts allows an efficient business management by avoiding the seasonality in wine sector.

The ‘fresh mushroom off-flavour’ has been recognized by the wine industry as an emerging defect since the 2000s. For many years, this off-flavour was not specifically characterized and rather grouped under ‘earthy’ and ‘musty’ taints. However, it has become increasingly problematic due to its rising prevalence. In some vineyards, incidents of this off-flavour now occur as frequently as once every five years. This trend may be associated with climatic changes affecting regions that are more prone to warm and wet seasons.

The current climate changes are directly threatening the balance of the vineyard at harvest time. The maturation period of the grapes is shifted to the middle of the summer, at a time when radiation and air temperature are at their maximum. In this context, the implementation of corrective practices becomes problematic. Unfortunately, our knowledge of the climate effect on the quality of different grape varieties remains very incomplete to guide these choices. During the Innovine project, original experiments were carried out on Syrah to study the combined effects of normal or high air temperature and varying degrees of exposure of the berries to the sun. Berries subjected to these different conditions were sampled and analyzed throughout the maturation period. Several quality characteristics were determined, including anthocyanin content. The objective of the experiments was to investigate which climatic determinants were most important for anthocyanin accumulation in the berries. Temperature and irradiance data, observed over time with a very thin discretization step, are called functional data in statistics. We developed the procedure SpiceFP (Sparse and Structured Procedure to Identify Combined Effects of Functional Predictors) to explain the variations of a scalar response variable (a grape berry quality variable for example) by two or three functional predictors (as temperature and irradiance) in a context of joint influence of these predictors. Particular attention was paid to the interpretability of the results. Analysis of the data using SpiceFP identified a negative impact of morning combinations of low irradiance (lower than about 100 μmol m−2 s−1 or 45 μmol m−2 s−1 depending on the advanced-delayed state of the berries) and high temperature (higher than 25oC). A slight difference associated with overnight temperature occurred between these effects identified in the morning.

Characteristics related to the climate and the soil of Montefalco in the centre of Italy have been defined in order to evaluate their influence on the red cv.