Leaf and must nitrogen content two complementary indicators of grapevine nitrogen status

Abstract

<p style="text-align: justify;">Grapevine nitrogen status was assessed by nitrogen content in leaf blade and petiole at veraison, in must at harvest and in pruned wood in December. The comparison of these indicators were done in vineyards bearing adults plants in the Atlantic and Mediterranean climates. Soil nitrogen offer were changed by soil grass cover, fertilization and irrigation. Leaf blade nitrogen (LBN) content cannot be simply predicted from soil texture, training characteristics and climate. Petiole and wood nitrogen content was less precise indicators compared to LBN content per unit dry weight. LBN content based on unit of leaf area usually constant along the growing season provides a complementary information on the leaf photosynthetic capacity and nitrogen availability for grapevine in summer. LBN content informs on the early growth grapevine access to soil and reserve nitrogen.</p><p style="text-align: justify;">Must and leaf blade nitrogen contents are significantly correlated. But it is shown that must N content is also changed by the yield and the soil capacity to provide nitrogen to the grapevine in summer. A simple predicting model of N in must is proposed. It is based on the availability of N in spring and summer and the positive effect of spring N on berry set up. Leaf blade and must N content considered both provided a complementary information on the grapevine N nutrition along the season.</p><p style="text-align: justify;">Sampling conditions for LBN content was tested. Primary leaves of a rank above 6 are very similar in N content and most representative of the grapevine N status. The LBN content on a leaf area basis is a more versatile expression because less variable along the growing season. The expressions of LBN content on the dry weight and leaf area can be obtained from a simple analysis by sampling leaf disks.</p>

Influence of two different cover crops on soil N availability, N nutritional status, and grape yeast-assimilable N (YAN) in a cv. Tempranillo vineyard

“…In addition, under our experimental conditions, FAN and YAN decreased under B cover crop in the third season, and positive relationships between FAN and YAN with the leaf N content in grapevine at bloom were found. In agreement with our results, Gaudillere et al (2003) found correlations between blade N content and N in must in vineyards under Atlantic and Mediterranean climates in France, and Neilsen et al (2010) described correlations between petiole-N at veraison and yeast-assimilable N in cv. Merlot under different rate, timing, and form of N fertilization.…”

A leaf gas exchange model that accounts for intra‐canopy variability by considering leaf nitrogen content and local acclimation to radiation in grapevine (Vitis vinifera L.)

“…Specifically, fertigation in Mtp explained the higher nitrogen content measured in this situation. For both sites, seasonal evolution of N m and LMA was similar to that previously reported for grapevine (Wermelinger & Koblet 1990; Gaudillère et al . 2003).…”

Performance of reflectance indices and of a handheld device for estimating in‐field the nitrogen status of grapevine leaves

“…In 2018, samples were collected on six dates representing flowering, veraison, ripening phase (~19°Brix), harvest, beginning of leaf yellowing and advanced senescence (Figure S3). At each sampling date, five mature primary leaves at rank 5 (Gaudillère et al ) from each west and east side of the canopy were sampled from each block and petioles were discarded. Optical measurements were made immediately after leaf sampling at one point on the terminal lobe within the intercostal space.…”