Nutrient uptake and distribution in young Pinot noir grapevines over two seasons

Authors: Schreiner, Roger - Paul

Submitted to: American Journal of Enology and Viticulture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/20/2016
Publication Date: 10/1/2016
Citation: Schreiner, R.P. 2016. Nutrient uptake and distribution in young Pinot noir grapevines over two seasons. American Journal of Enology and Viticulture. 67:436-448. doi: 10.5344/ajev.2016.16019.

Interpretive Summary: Nutrient uptake and use in 4-year-old Pinot noir grapevines was determined over two years in order to quantify the amounts of nutrients required, the time that nutrients are actively taken up from soil, and how they are used within the vine. For nitrogen, maximal uptake had occurred early in the season with most uptake occurring before bloom. Uptake of phosphorus and sulfur were also early compared to other nutrients with similar quantities of these elements taken up between budbreak and bloom, and between bloom and véraison. All other nutrients had peak uptake between bloom and véraison. Even in these young vines, about 35% of the nitrogen required by the canopy by the time fruit coloration began was remobilized from reserves in the roots and trunks. A smaller amount of potassium and sulfur were reused from stored reserves in the roots and trunks. The total quantities of different nutrients that were taken up from soil are presented and discussed.

Technical Abstract: The seasonal timing of biomass and nutrient uptake and distribution among different vine organs was determined over two growing seasons in 4-year-old Pinot noir grapevines carrying their first full crop and grown in field microplots. Vines were fertilized in spring and the biomass and nutrient contents of nine separate vine parts were measured at six phenological stages (budbreak, bloom, véraison, harvest, leaf-fall, and winter dormancy) each year. The uptake and distribution of four micronutrients (B, Zn, Mn, Cu) was determined for the first time in grapevines due to greater control of the soil environment and access to all roots within microplots. Whole vine N uptake was maximal early in the season with most N uptake occurring before bloom. Uptake of P and S were also early compared to other nutrients with similar quantities of these elements taken up between budbreak and bloom, and between bloom and véraison. All other macronutrients (K, Ca, Mg), and micronutrients (B, Zn, Mn, Cu) had peak uptake between bloom and véraison. Even in these young vines, remobilization of nutrients from permanent vine structures helped supply early season canopy needs for N, K, and S. More N was remobilized from reserves and this lasted until véraison, supplying about 35% of the N increase in the canopy between budbreak and véraison. Remobilization of K and S occurred only until bloom and contributed about 30% of the canopy increase in these elements up to that time. The small root fraction (that included fine primary and small woody roots) was the main source of remobilized nutrients for all three of these nutrients. A net annual gain of nutrients within the permanent vine parts had occurred for P, K, Ca, Mg, Zn and Cu, but none were as large as the relative gain in root and trunk biomass. The quantities of each nutrient required by young Pinot noir grapevines carrying a typical crop yield for the region are presented and discussed.