Scientia Horticulturae 202 (2016) 99–106 Contents lists available at ScienceDirect Scientia Horticulturae journal h om epage: www.elsevier.com/locate/scihorti Vegetative, physiological and nutritional behavior of new grapevine rootstocks in response to different nitrogen supply Maurizio Zamboni, Alessandra Garavani, Matteo Gatti, Alberto Vercesi, Maria Giulia Parisi, Luigi Bavaresco, Stefano Poni ∗ Department of Sustainable Crop Production (DI.PRO.VE.S.) – Università Cattolica del Sacro Cuore, Via Emilia Parmense, 84, 29122 Piacenza, Italy a r t i c l e i n f o Article history: Received 19 December 2015 Received in revised form 17 February 2016 Accepted 19 February 2016 Keywords: Vitis vinifera L. Mineral nutrition Vigor Gas-exchange Leaf chlorophyll Soil type a b s t r a c t Viticulture is in great need of new rootstocks sharing features of scion growth control and tolerance to major biotic and abiotic stress factors. A two year study was carried out in pots to assess performances of the two new M1 and M3 rootstocks vs. those of the commercial rootstocks 1103P and 101-14. Potted vines of M1, M3, 1103P and 101-14 rootstocks were grown in a calcareous and non calcareous soil and for two consecutive seasons subjected to three N supply levels at 0, 2 and 4 g of N per pot. Vegetative growth, leaf gas exchange, leaf greenness index (GI) and leaf blade nutrition were assessed. M1 and 1103P were the least vigorous genotypes in terms of total pruning weight; M1 also manifested a stronger apical dominance. Both M rootstocks and 101-14 showed increased leaf WUE at both N supply levels which was due to ability to maintain, at increasing N supply, similar leaf assimilation rates while significantly reducing leaf transpiration. Common tendency of any rootstocks was that increasing N supply corre- sponded to lowered leaf concentration of K, P, Mg and B. M1 was able to combine a series of desirable features including lower vigor, strong apical dominance, higher WUE at increasing N supply and quite well balanced leaf nutritional pattern. In the present trial M3 did not have the expected devigorating effect. © 2016 Elsevier B.V. All rights reserved. 1. Introduction Grafting is a standard practice in grape growing to overcome damage to the root system of Vitis vinifera L. vines caused by phyl- loxera (Daktulospheria vitifoilia Fitch) and to induce tolerance to other biotic and abiotic limiting factors (e.g. drought, flooding, salinity, etc.) (Cosmo et al., 1958; Carbonneau, 1985; Howell, 1987; Hardie and Cirami, 1988; Serra et al., 2013). Among these, toler- ance to high limestone leading, in turn, to severe iron chlorosis, has been successfully tackled in the past by selecting rootstocks which might thrive even at very high lime concentration in the soil (Pouget, 1980; Galet, 1988). Conversely, availability of root- stocks carrying tolerance to drought is still an open issue which is being exacerbated by the pressure of global warming. There are Abbreviations: C, calcareous; NC, non calcareous; tPW, total pruning weight; mcPW, main cane pruning weight; lPW, laterals pruning weight; A, assimilation rate; E, transpiration rate; gs , stomatal conductance; (WUE inst ), instantaneous water use efficiency; (WUE i ), intrinsic water use efficiency; (GI), greenness index. ∗ Corresponding author. Fax: +39 523599268. E-mail address: stefano.poni@unicatt.it (S. Poni). several grape growing districts worldwide which were tradition- ally non irrigated now facing the need of additional water supply (Palliotti et al., 2014). In such instances, availability of tolerant root- stocks could allow solving the problem without necessarily having to equip the vineyard with an irrigation system (Ezzahouani and Williams, 1995; Williams, 2010; Serra et al., 2013; Tramontini et al., 2013). Rootstock and graft union also exert profound influences on the vigor of the scion, yield and grape composition (Pouget, 1987; Wolf and Pool, 1988; Ollat et al., 2003). There is shared consensus that true semi-dwarf or dwarf rootstocks allowing permanent control of the vigor of the scion are still not available in viticulture. Therefore, unlike it usually happens in apple, there is little chance that vine growth and canopy size can be primarily controlled through the rootstock choice. More recently, the rootstock has gained attention as a quite reliable regulator of vine mineral uptake and transport (Delas and Pouget, 1979; Tardaguila et al., 1995; Keller et al., 2001; Bavaresco et al., 2003; Ibacache and Sierra, 2009; Peuke, 2009; Lecourte et al., 2015) showing significant impact on leaf and cluster mineral composition especially in regard to potassium (K), magne- sium (Mg) and iron (Fe). It is quite well known, for instance, that http://dx.doi.org/10.1016/j.scienta.2016.02.032 0304-4238/© 2016 Elsevier B.V. All rights reserved.