不同形态氮素施肥配比对'赤霞珠'葡萄酒氮素代谢和质量的影响OA

Different forms of nitrogen fertilization affect the grapevine growth and fruit quality.This study employed the wine grape variety'Cabernet Sauvignon'as the test material to explore the impacts of different nitrate-to-ammonium(NO3-∶NH4+)fertilization ratios(100∶0,75∶25,50∶50,25∶75,and 0∶100)on the sugar and acid content of grape berries,the fermentation characteristics of wine,the basic physicochemical indicators of wine,and the content of aroma compounds.Aroma sensory analysis and a comprehensive evaluation using membership functions were carried out,with no fertilization set as the control(CK).The results demonstrated that treatments with NO3-∶NH4+ratios of 50∶50 and 75∶25 significantly increased both reducing sugar content in berries and ethanol concentration in wines compared to the CK.During the process of alcoholic fermentation,nitrogen fertilization treatment promoted the nitrogen metabolism of wine.The order of free amino acids and assimilable nitrogen metabolism amounts from high to low among the treatment groups was 50∶50＞75∶25＞25∶75＞0∶100＞100∶0＞CK.Nitrogen treatment led to a reduction in the levels of isoamyl alcohol and isobutyric acid in wine.Meanwhile,it significantly increased the content of ethyl hexanoate and ethyl acetate,and the characteristic compounds benzyl alcohol and heptyl acetate were detected.Principal component analysis of the sensory aroma evaluation demonstrated that wines from the 50∶50 ammonium nitrate treatment presented the most diverse aroma profile types.Subordinate Function Comprehensive Evaluation showed that the 75∶25 and 50∶50 ammonium nitrate treatments had superior effects.This study offers theoretical support for selecting the optimal nitrogen fertilizer ratios in different forms for wine grapes and enhancing wine quality.