title: Rain-Shelter Cultivation Modifies Carbon Allocation in the Polyphenolic and Volatile Metabolism of Vitis vinifera L. Chardonnay Grapes.
abstract: This study investigated the effect of rain-shelter cultivation on the biosynthesis of flavonoids and volatiles in grapes, with an aim of determining whether rain-shelter application could help to improve the sensory attributes and quality of grapes. Vitis vinifera L. Chardonnay grapes, grown in the Huaizhuo basin region of northern China, were selected within two consecutive years. A rain-shelter roof was constructed using a colorless polyethylene (PE) film with a light transmittance of 80%. Results showed that rain-shelter treatment did not affect the accumulation of soluble solids during grape maturation. However, the allocation of assimilated carbon in phenolic and volatile biosynthetic pathways varied significantly, leading to alterations in polyphenolic and volatile profiles. The rain-shelter cultivation enhanced the concentration of flavan-3-ols via the flavonoid-3'5'-hydroxylase (F3'5'H) pathway, but reduced the level of flavonols and flavan-3-ols via the flavonoid-3'-hydroxylase (F3'H) pathway. In addition, the rain-shelter cultivation significantly enhanced the synthesis of fatty acid-derived volatiles, isoprene-derived terpenoids and amino acid-derived branched-chain aliphatics, but led to a decrease in the accumulation of isoprene-derived norisoprenoids and amino acid-derived benzenoids. Principal component analysis revealed some key compounds that differentiated the grapes cultivated under open-field and rain-shelter conditions. Moreover, the effect of the rain-shelter application on the accumulation of these compounds appeared to be vintage dependent. The alteration of their profiles caused by the rain-shelter treatment was significant in the vintage that received higher rainfall, which usually took place in the first rapid growth and veraison phases.
authors.affiliation: Center for Viticulture and Enology, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Gao
authors.affiliation: Center for Viticulture and Enology, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China.
authors.forename: Xiao-Xi
authors.initials: XX
authors.lastname: Li
authors.affiliation: Center for Viticulture and Enology, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China.
authors.forename: Mei-Mei
authors.initials: MM
authors.lastname: Han
authors.affiliation: Center for Viticulture and Enology, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China.
authors.forename: Xiao-Fan
authors.initials: XF
authors.lastname: Yang
authors.affiliation: Food Science and Human Nutrition Department, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, Florida, United States of America.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Li
authors.affiliation: Center for Viticulture and Enology, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Wang
authors.affiliation: Center for Viticulture and Enology, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China.
authors.forename: Qiu-Hong
authors.initials: QH
authors.lastname: Pan
mesh_terms: D000383:Agriculture / Q000379:methods*; D002244:Carbon / Q000378:metabolism*; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D005419:Flavonoids / Q000032:analysis / Q000096:biosynthesis*; D053858:Metabolic Networks and Pathways; D010940:Plant Proteins / Q000378:metabolism; D059808:Polyphenols / Q000032:analysis / Q000096:biosynthesis; D025341:Principal Component Analysis; D011891:Rain; D027843:Vitis / Q000201:enzymology / Q000254:growth & development* / Q000378:metabolism
chemical_list: D005419:Flavonoids; D010940:Plant Proteins; D059808:Polyphenols; D002244:Carbon; D003577:Cytochrome P-450 Enzyme System; C084258:flavonoid 3',5'-hydroxylase; C038888:flavonoid 3'-hydroxylase