Different yield regulation strategies in semi-minimal-pruned hedge (SMPH) and impact on bunch architecture

Le vigneron européen est de plus en plus à la recherche de la valorisation de son terroir par la personnalisation de la typicité de ses produits. Dans ce contexte, il est apparu depuis longtemps que la part des facteurs technologiques ou humains est d’une importance capitale face aux conditions de l’envirormement naturel. Le terroir se construit plus qu’il ne se subit.

In sparkling wines, foam is a relevant aspect whose measurement method could affect the results. The shaking test (ST) is a simple method measuring foamability1,2

Farming management practices aiming at conserving soil moisture have been developed in arid and semiarid-areas facing water scarcity problems. Organic mulching is an effective method to manipulate the crop-growing microclimate increasing crop yield by controlling soil temperature, and retaining soil moisture by reducing soil evaporation. In this sense, the effectiveness of different organic mulching materials (straw mulch and grapevine pruning debris) applied within the row of a vineyard was evaluated on the soil and on the vine in a Tempranillo vineyard located in La Rioja (Spain). Organic mulches were compared with a traditional bare soil management technique (based on the use of herbicides to avoid weed incidence). Mulching coverages favourably influenced the soil water retention throughout all the grapevine vegetative cycle. However, the soil-moisture variation was not the same under different mulching materials, being the straw mulch (SM) the one that retained more water in comparison with grapevine pruning debris (GPD) based-cover. The changes of soil moisture in the upper surface layer (0–10 cm) were highly dynamic, probably due to water vapour fluxes across the soil-atmospheric interface. However, both, SM and GPD reduced these fluctuations as compared with bare soils. A similar trend occurred with soil temperature. Both organic mulches altered soil temperature in comparison with bare soil by reducing soil temperature in summer and raising it in winter. Moreover, the same buffering effect for the temperature on the covered soil also remains in the deeper layers. To conclude, we could see that organic mulching had a positive impact on soil-moisture storage and soil temperature and the extent of this effect depends on the type of mulching materials. These changes led to higher rates of photosynthesis and stomatal conductivity compared to bare soils, also favouring crop growth and grape yields.

Identification and characterisation of terroirs depends on knowledge of environmental parameters, functioning of the grapevine and characteristics of the final product. A network of plots of Sauvignon blanc was delimited in commercial vineyards in proximity to weather stations at 20 localities and their viticultural and oenological response was monitored for a period of seven years. These experimental plots were further characterised with respect to climate, soil and topography.

High temperatures influence plant development and induce a large set of physiological responses at the leaf scale. Stomatal closure is one of the most observed responses to high temperatures. This response is commonly considered as an adaptive strategy to reduce water loss and embolism in the vascular system caused by the high evaporative demand.