## 2 Materials and Methods  
### Experiment Location and Plot Settings  
This study was conducted for one growing season (2017) on 11-year-old homogeneous potted vines (average number of leaves/vine 103.5; average shoot length after topping 73.2 cm; average canopy leaf area/vine 1.13 m\({}^{2}\)) (_Vitis vinifera_) of cv. Pinot nor (clone Entav 115), grafted on 1103 Paulsen rootstock and grown outdoor at CREA-VE, Arezzo, Italy (Lat. 43.476\({}^{\circ}\) N, Long. 11.824\({}^{\circ}\) E; 260 m a.s.l.). Pots (70 L) were filled with a clay-loam soil with the following average characteristics: clay 40%; silt 35%; and sand 25%, with a volumetric soil water content of \(\sim\)34% at field capacity, collected from a vineyard of the Chianti Classico D.O.C.G. district in Tuscany, Italy [51]. The vines were trained on vertical shoot positioned trellis, with spur cordon pruning and an average of 10 buds per vine. Every year, at the end of February, each container was fertilized with 40 g of controlled-release fertilizer (Nitrophoska, 12N-12P-17K, Eurochem Agro, Cesano Maderno (MB), Italy). To avoid excessive soil over warming, which can negatively affect roots, and maintain a stable temperature, pots were protected by wrapping their lateral surface with a shade net.  
At the beginning of the experiment (veraison, modified Eichorn and Lorenz (E-L) stage 35; 13 July 2017), 20 plants were maintained at 90% of maximum water availability as controls (WW, well-watered vines) until harvest (E-L stage 38), while the other 20 plants were subjected to a water deficit at 40% of maximum water availability (WS, water-stressed) [52]. The water regime was imposed later in the season, because post-veraison water deficit tends to have greater effects on berry ripening as compared to pre-veraison stress, which, conversely, affects primarily berry size [53]. Until the beginning of treatment, all plants were maintained at field capacity. During water limitation, the surface of the plant containers was covered with aluminum foils to avoid rainfall interference and to minimize soil water evaporation. The water supply per pot was determined monitoring the soil moisture, as volumetric content, by time domain reflectometry using Trace System 1 (Soil Moisture Equipment Corporation, Goleta, CA, USA). Readings were taken every day in the early morning with 30 cm long electrodes located in the pots. In each pot, water was supplied at 2 day intervals with drip irrigation emitters.  
During the differential irrigation period, ten of the WW vines and ten of the WS ones were treated twice with 3 g/L of a noncommercial _A. nodosum_ extract (SWE) [35; 46; 49]. This extract is mainly rich in amino acids, among which the most abundant were alanine, phenylalanine, proline, and methionine. A full extract characterization was provided in [PERSON] et al. [46]. The first application was performed approximately 20 days before the expected harvest (E-L stage 36; 27 July 2017) and another one was repeated after 14 days (E-L stage 37; 10 August 2017) on the same plants. On the same days, the other ten vines of WW and ten vines of WS were sprayed with the same amount of water (CTRL).  
At three stages, on 10 vines/treatment, berries samplings and eco-physiological measurements were conducted: t\({}_{0}\) (before _A. nodosum_ treatments and one week after irrigation regimes differentiation; E-L stage 36; 20 July 2017), t\({}_{1}\) (7 days after the first _A. nodosum_ treatment; E-L stage 37; 3 August 2017), and t\({}_{2}\) (7 days after the second _A. nodosum_ treatment; E-L stage 38; 17 August 2017).