Effect of Covering Crops between Rows on the Vineyard Microclimate, Berry Composition and Wine Sensory Attributes of ‘Cabernet Sauvignon’ (Vitis vinifera L. cv.) Grapes in a Semi-Arid Climate of Northwest China

Abstract

Covering crops was a commonly used viticultural technique to adjust the vineyard microclimate, thus affecting the grape and wine quality. In this two-year study, the purslane (Portulaca oleracea L.) was used to cover the lands between rows in the vineyards located in the semi-arid Northwest China, Xinjiang. Results showed that the photosynthetically active radiation around the fruit zone and the temperature with the purslane covering treatment decreased. Compared with the clean tillage, covering purslane had lower TSS and higher TA in the grape berries, while lower alcohol content and higher TA was also found in their corresponding wines. Covering purslane treatment significantly increased the contents of anthocyanin and flavonol in the grapes and wines in the year 2018, but no significant effect on flavanols was observed in the wines. Norisoprenoids, esters, and C6 alcohols in the grapes and wines were increased in the purslane covering treatment, respectively. Additionally, compared to the clean tillage, the purslane covering treatment significantly improved the sensory value of the wines, especially the floral aroma and the complexity of the wines. This study helped us to better understand the feasibility of applying covering purslane in viticulture in the semi-arid climate of Northwest China.

Effect of Inter-Row Peanut Growing in the Vineyard on the Quality of ‘Cabernet Sauvignon’ Grape Fruits and Wines in Northwest China

“…In 2018 and 2019, when this experiment was conducted, the two consecutive years were normal years in Xinjiang according to local weather reports. We chose the same experimental vineyard as Peng et al [ 19 ], which is located in Manas County, Xinjiang Uygur Autonomous Region, at the Northern Foot of the Tianshan Mountains. The variety used in the experiment was ‘Cabernet Sauvignon’ ( V. vinifera L.…”

“…We installed microclimate stations (Hobo ® micro station, Onset Corporation, Bourne, MA, USA) in the fruit-zone of clean tillage and covering peanuts. The temperature and photosynthetically active radiation (PAR) were recorded every 5 min on a sunny day during the post-veraison and pre-harvest periods [ 19 ].…”

“…At harvest, the grape yield was monitored by weighing the cluster weight of the vines. During winter pruning, the canes were pruned and weighed on five vines per replicate [ 19 ].…”

“…The TSS in grapes was measured using the PAL-1 digital handheld refractometer (Atago, Tokyo, Japan). The TA was analyzed by titration with NaOH (0.05 M) to a final pH of 8.2 and expressed as tartaric acid equivalents according to the National Standard of the People’s Republic of China [ 19 , 21 ]. The value of pH was measured with the Mettler LE438 pH meter (Mettler, Toledo, Switzerland).…”

“…To the best of our knowledge, there were only a few studies in Northwest China on the use of covering crops to determine the quality of grapes and wine, and there are no studies on inter-row peanuts in vineyards, especially those based on sensory evaluation [ 17 , 18 , 19 ]. In this study, the results show that covering peanuts could improve the aroma and taste expression in wines, offering great potential for producing high quality wines in this region, compared to clean tillage.…”