Combined effects of soil-applied and foliar-applied nitrogen on the nitrogen composition and distribution in water stressed "<em>Vitis vinifera</em> L." cv Sauvignon blanc grapes

Abstract

&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Aims&lt;/strong&gt;: The aim of this work is to test the effects of soil-applied nitrogen (N) at budbreak and subsequent foliar-applied N at veraison on the N composition and partitioning in berries of water stressed Vitis vinifera L. cv. Sauvignon blanc vines.&lt;/p&gt;&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Methods and results&lt;/strong&gt;: N fertilizer was applied to the soil at budbreak at doses of 30 or 60 kg N/ha, while the control did not receive any treatment. This did not increase N content of leaves and the vines showed symptoms of N deficiency from the beginning of the season. In order to overcome this deficiency, N foliar sprayings were applied at veraison at doses of 2.5 or 5 kg N/ha to vines having received 30 or 60 kg N/ha of soil-applied N, respectively. Total N of berry flesh responded to N foliar fertilization more than that any other berry part, whereas amino acids in skins were the more affected by N foliar fertilization than those of other berry parts. Only the 60 soil/5 foliar N treatment produced a measurable increase in the total, assimilable and amino N in berry juices at maturity. Assimilable N was a better indicator for N summer uptake by the vine than total N. Of all amino acids, arginine showed the highest increases following N fertilization and could be considered among the better indicators to distinguish between N summer fertilization treatments.&lt;/p&gt;&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Conclusion&lt;/strong&gt;: In conditions of severe water deficit and N deficiency, fertilization at a dose of 60 kg/ha soil-applied N combined with 5 kg/ha foliar-applied N improved fruit fermentability. Results support the use of foliar fertilization at veraison as a tool for enhancing grape quality and to a certain extent the style of wine.&lt;/p&gt;&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Significance and impact of study&lt;/strong&gt;: This work helps to provide insight into the effect of N soil fertilization along with foliar fertilization on waterstressed vines. This may be useful in fertilization programs in the Mediterranean area and may help to choose the type and the rate of the N fertilization in case of severe vine water deficit. Also, we provide information of utmost importance on the distribution of summer foliarapplied N in grape tissues.&lt;/p&gt;

Nitrogen and Sulphur Foliar Fertilisation

“…The nutrition levels of a grapevine can influence the grape's composition and eventually the wine's composition and quality (Bell & Henschke, 2005). A grapevine's nutrition can be affected by various factors, such as the canopy shading (Perez-Harvey & Witting, 2001), canopy temperature (Ewart & Kliewer, 1977), cultivar (Christensen, 1984;Huang & Ough, 1989), rootstock (Christensen, 1984;Huang & Ough, 1989), season (Bell & Robson, 1999), site (Huang & Ough, 1989), soil management (Bell et al, 1979), training system (Kliewer et al, 1991), and the timing, rate and form of application of fertiliser (Bell et al, 1979;Peacock et al, 1991;Spayd et al, 1994;Christensen & Peacock, 2000;Conradie, 2001;Dufourcq et al, 2007;Lacroux et al, 2008;Jreij et al, 2009).…”

“…Nitrogen foliar fertilisation can be applied using urea (Lacroux et al, 2008;Dufourcq et al, 2009;Jreij et al, 2009;Wolf, 2012;Garde-Cerdán et al, 2015;Juhasz, 2015;Verdenal et al, 2015a;Garde-Cerdán et al, 2016;Geffroy et al, 2016a;Hannam et al, 2016;Verdenal et al, 2016;Dienes-Nagy et al, 2017) or amino acids (Garde-Cerdan et al, 2015). Application levels for these studies ranged from 2 to 36 kg N/ha.…”

“…A synergy between nitrogen and sulphur results in interactions between the pathways (Téa et al, 2003;Lacroux et al, 2008). The timing of foliar sprays is critical, and nitrogen and sulphur can be applied at different stages, such as during véraison (Dufourcq et al, 2009;Jreij et al, 2009;Garde-Cerdán et al, 2015;Juhasz, 2015;Verdenal et al, 2015a;Garde-Cerdán et al, 2016;Geffroy et al, 2016a;Hannam et al, 2016;Verdenal et al, 2016;Dienes-Nagy et al, 2017), before véraison (Lacroux et al, 2008) or at the flowering stage (Wolf, 2012;Verdenal et al, 2015a).…”

“…Foliar fertilisation studies on nitrogen and sulphur applications cover a wide range of red and white cultivars and were performed in various places, such as Canada, Chile, France, Spain, South Africa, Switzerland and Virginia, USA. White cultivars included Chardonnay (Dienes-Nagy et al, 2017), Chasselas (Verdenal et al, 2015a(Verdenal et al, , 2015b(Verdenal et al, , 2016Dienes-Nagy et al, 2017;Koestel et al, 2017), Colombard (Dufourcq et al, 2005(Dufourcq et al, , 2009Geffroy et al, 2016aGeffroy et al, , 2016b, Gewürztraminer (Dienes-Nagy et al, 2017), Gros Manseng (Dufourcq et al, 2007(Dufourcq et al, , 2009Geffroy et al, 2016aGeffroy et al, , 2016b, Melon Geffroy et al, 2016aGeffroy et al, , 2016b, Négrette (Dufourcq et al, 2005(Dufourcq et al, , 2009Geffroy et al, 2016aGeffroy et al, , 2016b, Sauvignon blanc (Dufourcq et al, 2011;Lacroux et al, 2008;Dufourcq et al, 2009;Jreij et al, 2009;Geffroy et al, 2010;Lasa et al, 2012;Wolf, 2012;Helwi et al, 2014;Juhasz, 2015;Geffroy et al, 2016aGeffroy et al, , 2016bDienes-Nagy et al, 2017; and Viognier (Hannam et al, 2014). Red cultivars such as Cabernet Sauvignon (Hannam et al, 2014;Gutiérrez-Gamboa et al, 2017a), Carignan (Geffroy et al, 2012…”

“…Foliar fertilisation research studies have analysed °B, TA, pH, berry composition, total nitrogen content, berry volume, YAN, amino acids, ammonium, IBMP, and susceptibility to pathogens in the grapes during grape berry ripening and at harvest (Lacroux et al, 2008;Jreij et al, 2009;Mundy et al, 2009;Hannam et al, 2014;Dienes-Nagy et al, 2017;Kelly et al, 2017). No foliar fertilisation studies focused on all the methoxypyrazine compounds, except on IBMP, or on the composition of separate amino acids during ripening or at harvest.…”