Wang Yu, Li Hui-Qing, Gao Xiao-Tong, Lu Hao-Cheng, Peng Wen-Ting, Chen Wu, Li Shu-De, Li Sui-Ping, Duan Chang-Qing, Wang Jun
Center for Viticulture & Enology, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China; Key Laboratory of Viticulture and Enology, Ministry of Agriculture and Rural Affairs, Beijing 100083, China.
CITIC Guoan Wine Co. Ltd., Manas 832200, Xinjiang, China.
Food Res Int. 2020 Nov;137:109688. doi: 10.1016/j.foodres.2020.109688. Epub 2020 Sep 22.
In this study, fruit-zone microclimate was modified by three treatments, including inter-row mulch (M), the combination of leaf removal applied at the onset of veraison and inter-row mulch (MLR-BV), and the combination of leaf removal applied at complete veraison and inter-row mulch (MLR-EV), in a semi-arid climate in three consecutive years (2015-2017). M decreased fruit-zone reflected solar radiation from vineyard floor and low temperature (10-20 °C) duration, whereas it increased soil temperature and high temperature (> 30 °C) duration. MLR-BV and MLR-EV increased fruit-zone incident photosynthetically active radiation while decreased the duration of 20-25 °C compared to M. Notably, M significantly decreased grape total norisoprenoid concentrations in 2015-2017, and total terpenoid concentrations in 2015-2016. Applying leaf removal applied at the onset of veraison could compensate the decreases of total norisoprenoids and terpenoids caused by M when two treatments were applied together. Besides, M significantly increased grape total C/C compound concentrations, besides, (Z)-3-hexen-1-ol concentrations were significantly higher in grapes of M than those of MLR-BV in 2015-2017. Light exposure and high temperature duration after veraison had strong positive correlations with total norisoprenoids and terpenoids, besides, low temperature duration was positively correlated with total norisoprenoids. In addition, light exposure after veraison had strong negative correlations with total C/C compounds. With respect to the volatile compounds in wines, M significantly decreased the concentrations of isopentanol and ethyl acetate, and the concentrations of ethyl cinnamate, phenylacetaldehyde, phenylethyl alcohol and 3-methylthio-1-propanol were significantly lower in MLR-BV and MLR-EV than in M. The outcome of this study can assist winegrowers to properly adjust vineyard managements to optimize the concentrations of desired volatile compounds in grapes and wines.
在本研究中，在连续三年（2015 - 2017年）的半干旱气候条件下，通过三种处理方式对果实区域的小气候进行了改良，包括行间覆盖（M）、在转色初期进行去叶处理并结合行间覆盖（MLR - BV）以及在完全转色时进行去叶处理并结合行间覆盖（MLR - EV）。M降低了果实区域来自葡萄园地面的反射太阳辐射以及低温（10 - 20°C）持续时间，而提高了土壤温度和高温（> 30°C）持续时间。与M相比，MLR - BV和MLR - EV增加了果实区域的光合有效辐射入射量，同时减少了20 - 25°C的持续时间。值得注意的是，M在2015 - 2017年显著降低了葡萄中的总类异戊二烯浓度，在2015 - 2016年显著降低了总萜类化合物浓度。当两种处理方式一起应用时，在转色初期进行去叶处理可以弥补M导致的总类异戊二烯和萜类化合物的减少。此外，M显著提高了葡萄中的总C/C化合物浓度，而且在2015 - 2017年，M处理的葡萄中（Z）- 3 - 己烯 - 1 - 醇浓度显著高于MLR - BV处理的葡萄。转色后的光照和高温持续时间与总类异戊二烯和萜类化合物呈强正相关，此外，低温持续时间与总类异戊二烯呈正相关。另外，转色后的光照与总C/C化合物呈强负相关。关于葡萄酒中的挥发性化合物，M显著降低了异戊醇和乙酸乙酯的浓度，并且MLR - BV和MLR - EV中肉桂酸乙酯、苯乙醛、苯乙醇和3 - 甲硫基 - 1 - 丙醇的浓度显著低于M。本研究结果可帮助葡萄种植者适当调整葡萄园管理措施，以优化葡萄和葡萄酒中所需挥发性化合物的浓度。
