Effect of Seasonal Nitrogen Applications on Grapevine N Status, Grape Yield and Quality, Amino-N Composition and Fermentation Dynamics for Merlot Grafted Onto Two Rootstock Cultivars that Differ in Shoot Vigor

Download or read book Effect of Seasonal Nitrogen Applications on Grapevine N Status, Grape Yield and Quality, Amino-N Composition and Fermentation Dynamics for Merlot Grafted Onto Two Rootstock Cultivars that Differ in Shoot Vigor written by Christine Marie Armstrong-Stockert and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Seasonal nitrogen (N) application and two rootstock cultivars that differed in potential growth rate (vigor) were compared for vine biomass, vine N status, fruit yield and quality, must amino-N composition and fermentation dynamics. The rootstock 1103 Paulsen (Vitis berlandieri x V. rupestris cv 1103P) has a root system that tends to provide high shoot growth. The other rootstock was 101-14 Millardet de Gramanet (V. riparia x V. rupestris cv 101-14 Mgt.), a root system associated with lower shoot growth. Vines were given N in the fall (FF) and spring (SF) or no nitrogen (NF) in an established Merlot (Vitis vinifera cv Merlot) experimental block in Oakville, CA. Merlot grown on the 1103P vines had two times the yeast-assimilable nitrogen (YAN) concentration as Merlot grown on the 101-14 Mgt. vines. In essence, the difference in nitrogen metabolite levels between the two rootstocks indicated 1103P roots are much more effective at absorbing and translocating N whether it was from fertilizer or the soil mineral pool. The data also suggest that Merlot vines on 1103P rootstocks in the Napa Valley may require little to no N supplementation while Merlot grown on 101-14 Mgt. may require N supplementation to avoid slow or stuck fermentations. Furthermore, within rootstock treatments, YAN levels alone did not explain observed rates of fermentation, suggesting that other metabolites may play an important role in fermentation dynamics.