Nitrogen Distribution in Annual Growth of ‘Italia’ Table Grape Vines

Abstract

Little information is available about nitrogen (N) content and its concentration in table grape vines. Knowledge of the quantity of N accumulated by the vine organs during the season could support sustainable fertilization programs for table grape vineyards. The aim of the present study was to determine the N content and its concentration in different annual organs, including summer and winter pruning materials, clusters at harvest, and fallen leaves at post-harvest. Specifically, biomass and N were analyzed at six phenological growth stages (flowering, berry-set, berry growth, veraison, ripening, and harvest) from 2012 to 2015. Nitrogen concentration was highest (>40 g/kg d.w.) in the leaves of the secondary shoots at flowering, whereas values >30 g/kg were measured in the leaves of the primary shoots. Nitrogen concentration in the clusters at harvest was 5.3–7.6 g/kg with an accumulation of 18.6–25.4 g/vine in the seasons. The decrease of N content in the primary leaves after flowering indicated a remobilization toward the clusters, which acted as a stronger sink. Later in the season (veraison-ripening), leaves translocated N to permanent organs and primary stems. Pruned wood and fallen leaves accounted for the largest N removal from the vine after clusters, 6.0–7.9 and 9.2–10.2 g/vine, respectively. With regard of the vine annual biomass, the growth followed a sigmoidal model reaching 7300–7500 g of d.w./vine at harvest. Vine leaf area, including both primary and secondary leaves, peaked at veraison (17–21 m2). Vines accumulated ≅35 g/vine of N at harvest, not considering the N removed with the intense summer pruning practices (≅7 g/vine) and the fraction mobilized toward the storage organs (10–15 g/vine). The overall N required by the vine was around 50–55 g/vine, which corresponded to ≅80 kg of N/ha in a vineyard with 1500 vines and a yield of 40 t/ha. Summer and winter pruning practices removed 29–31 g/vine of N which will be partly available (to be considered in the fertilization schedule) for the vine in the successive years if pruned residues were incorporated and mineralized in the soil.

Cover Crop for a Sustainable Viticulture: Effects on Soil Properties and Table Grape Production

“…Overall, cover crops slightly modified the grape color, with a more saturated and vivid yellow in the conventional plot, although without compromising the production quality in the cover crop treatment. In fact, the grape colorimetric characteristics observed in the presence of cover crops were in accordance with values usually detected for cv "Italia" grapes produced in the south of Italy [44]. Data reported in the literature about the effect of cover crops on grape color mainly refer to red wine grape varieties [10,39], thus no comparison can be done with our data.…”

Nutritional status differentially affect yield and must composition of hybrids andV. viniferavarieties established under cold climate conditions

“…Low N status may be associated with berry growth (Hilbert et al, 2003;Rogiers et al, 2004). Similar to our results, it was reported that in "Italia" ("Bicane"  "Muscat Hamburg") grapevines, the decrease of N content in the primary leaves after flowering indicated a remobilization toward the clusters, which acted as a stronger sink (Ferrara et al, 2018). As "Italia", "New York Muscat" ("Muscat Hamburg"  "Ontario") is a vigorous and woody grapevine that is characterized by clusters of edibles, juicy, sweet, dark maroon to blue-black fruit.…”

A Novel Machine Learning Approach to Estimate Grapevine Leaf Nitrogen Concentration Using Aerial Multispectral Imagery

“…Insufficient N limits vine vigor [6,7]. On the other hand, unnecessary application of N fertilizers needlessly increases the production cost, may cause unintended nutrient imbalances, contributes to environmental contamination [8]), stimulates excess vegetative growth, and reduces grape quality [9]. In fact, excessive application of nitrogen to crop plants has led to significant nitrate groundwater pollution in the SJV [10].…”