College of Enology, Northwest A&F University, Yangling 712100, PR China.
College of Enology, Northwest A&F University, Yangling 712100, PR China.
Food Res Int. 2020 May;131:109028. doi: 10.1016/j.foodres.2020.109028. Epub 2020 Jan 25.
Monoterpenes contribute to the varietal aromas of grapes and wines. We determined the effects of cluster zone leaf removal on the monoterpene profiles of Sauvignon Blanc grape berries and wines, and on the expression of key genes in the terpenoid pathway. Leaf removal at two intensities (half basic, 50%; full basic, 100%) was conducted at two weeks before veraison, veraison, and two weeks after veraison. Half basic leaf removal increased the pH and decreased the tartaric acid content in grapes and wines. The concentrations of most free- and bound-form monoterpenes in grapes were increased by early leaf removal. The total monoterpene contents were increased in wines in the defoliation treatments, but were significantly lower in wines from the full basic leaf removal treatments than in wines from the half basic leaf removal treatments. The defoliation treatments resulted in increased transcript levels of some key genes in terpene biosynthesis (VvPNLinNer1, VvPNLinNer2, VvPNLNGl1, VvPNLNGl2, and VvUGT88A1L1).
单萜烯贡献了葡萄和葡萄酒的品种香气。我们确定了在葡萄浆果和葡萄酒中，在葡萄转色前两周、转色期和转色后两周，分两次（半基础去除 50%，全基础去除 100%）去除果穗周围叶片对单萜烯谱的影响，以及萜烯途径中关键基因的表达。半基础叶片去除会增加葡萄和葡萄酒的 pH 值并降低酒石酸含量。早期叶片去除会增加葡萄中大多数游离和结合形式单萜烯的浓度。在叶片去除处理中，葡萄酒中单萜烯的总量增加，但在全基础叶片去除处理的葡萄酒中单萜烯的含量明显低于半基础叶片去除处理的葡萄酒。叶片去除处理导致萜烯生物合成的一些关键基因（VvPNLinNer1、VvPNLinNer2、VvPNLNGl1、VvPNLNGl2 和 VvUGT88A1L1）的转录水平增加。
