The effect of whole cluster at 50% (50% WC) and 100% additions (100% WC), as well as that of Dried stems (DS) on Pinot noir wines from the Edna Valley AVA of California (USA) were investigated over two consecutive vintages at commercial scale. Additions of 100% WC led to significant increases in pH and volatile acidity. Anthocyanins, polymeric pigments, and color were more influenced by vintage than by the winemaking treatments, but in the case of 100% WC wines, they were either unaffected or negatively affected. Conversely, the tannin content of the wines increased more or less proportional to the percentage of whole clusters and stems added, that is, 68% (50% WC), 100% (100% WC) and 90% (DS) in 2016 and 61% (50% WC), 123% (100% WC) and 137% (DS) in 2017, relative to Control (C) wines. GC-MS data showed higher relative levels of ethyl cinnamate and benzaldehyde in 100% WC wines and relative abundance of esters in DS wines. Descriptive sensory analysis showed that 100% WC additions led to vegetal, cooked fruit flavors and spicy (clove) notes, whereas DS additions produced wines that were more herbal, fruity and astringent, with lifted fruity notes related to esters, and astringency sensations related to enhanced tannin extraction from the stems. Both whole clusters and dried stem additions led to variable increases in perceived astringency, suggesting that they can be used to add mouthfeel and improve texture in Pinot noir wines.

Unlike most crop industries, there is a strongly held belief within the wine industry that increased vine age correlates with quality. Considering this perception could be explained by vine physiological differences, the purpose of this study was to evaluate the effect of vine age on phenology and gas exchange parameters. An interplanted, dry farmed, Zinfandel vineyard block under consistent management practices in the Central Coast of California was evaluated over two consecutive growing seasons. Treatments included Young vines (5 to 12 years old), Control (representative proportion of young to old vines in the block), and Old vines (40 to 60 years old). Phenology, leaf water potential, and gas exchange parameters were tracked. Results indicated a difference in phenological progression after berry set between Young and Old vines. Young vines progressed more slowly during berry formation and more rapidly during berry ripening, resulting in Young vines being harvested before Old vines due to variation in the timing of sugar accumulation. No differences in leaf water potential were found. Young vines had higher mid-day stomatal conductance and tended to have higher mid-day photosynthetic rates. The results of this study suggest vine age is a factor in phenological timing and growing season length.

Background and Aims. No-till is considered a core practice of conservation and climate-smart agriculture. Nevertheless, recent evidence suggests that the benefits of this practice for climate change mitigation might be overestimated, particularly in the short term. Methods and Results. In a three-year field experiment, we investigated the environmental and agronomic performance of this practice by looking at changes in soil physical properties, C and N pools, as well as vine yield and grape quality. No-till increased stratification in the distribution of active soil C (POXC), further accentuating the already existing difference between top and subsoil. No-till also slightly reduced the daily efflux of CO₂ from the soil during the rainy season, showing that these plots were less prone to lose C than tilled plots. Nonetheless, no-till did not increase total soil C stocks. This, together with the lack of differences in cumulative N₂O emissions, resulted in similar global warming potential in till and no-till plots. Vine yield and grape quality remained unchanged in the no-till compared to the tilled plots. Conclusions. Even though no-till did not result in short-term climate change mitigation, results of this study suggest changes in the ecological processes leading to C accumulation and mineralization and that may result in future C sequestration. There were no deleterious effects of no-till on grape yield and quality. Significance of the Study. This study shows that reducing tillage intensity in vineyards is a feasible strategy from an agronomic standpoint.