Effects of surface and subsurface drip irrigation on physiology and yield of ‘Godello’ grapevines grown in Galicia, NW Spain

Abstract

SUMMARYIrrigation has been considered a controversial practice in European traditional viticulture due to potential alterations in the balance between vegetative growth and yield. In this regard, the influence of surface (DI) and subsurface (SDI) drip irrigation on physiological performance of the 'Godello' grapevine (Vitis vinifera L.) cultivar was compared with a non-irrigated control (R) over three consecutive growing seasons (2012)(2013)(2014) in NW Spain. Irrigation improved vine water status; R plants reached a minimum of midday leaf water potential of -1.5 MPa, whereas DI and SDI plants reached -1.3 MPa. Stomatal conductance was unaffected by irrigation as well as chlorophyll a fluorescence. However, photosynthetic pigments were present at higher concentrations in leaves from irrigated plants than in those from R plants in 2013. In addition, R plants showed higher values for the indicators of oxidative damage. No significant yield improvements were observed for irrigated plants, although the trend was to obtain slightly higher yields under irrigation in years with low rainfall amounts. This may not encourage growers to establish irrigation systems on their vineyards. However, these results may be important with the objectives of stabilizing yield from year to year. RESUMOA rega tem sido considerada uma prática controversa na viticultura tradicional Europeia devido a potenciais alterações no equilíbrio entre crescimento vegetativo e rendimento. A este respeito, a influência da irrigação por gotejamento superficial (DI) e subsuperficial (SDI) sobre o desempenho fisiológico da variedade 'Godello' (Vitis vinifera L.) foi comparada com uma testemunha em condições de sequeiro (R) ao longo de três anos consecutivos (2012-2014) no noroeste de Espanha. A rega melhorou o estado hídrico da videira; as plantas do tratamento R atingiram potenciais hídricos foliares ao meio-dia de -1.5 MPa, comparativamente a um valor de -1.3 MPa para as plantas dos tratamentos DI e SDI. A conductância estomática e a fluorescência da clorofila a não foram afectadas pela rega. No entanto, os pigmentos fotossintéticos apresentaram maiores concentrações em folhas de plantas regadas quando se comparam com as plantas do tratamento R em 2013. Além disso, as plantas do tratamento R apresentaram valores superiores para os indicadores de danos oxidativos. Não foi detectado nenhum incremento do rendimento nas plantas regadas, embora se tenha observado uma tendência para obtenção de rendimentos ligeiramente mais elevados sob rega em anos com baixa pluviosidade. Tal poderá não encorajar aos viticultores a implementar sistemas de rega nas suas vinhas. No entanto, estes resultados podem ser importantes para a estabilização do rendimento de ano para ano.

Effects of Two Different Irrigation Systems on the Amino Acid Concentrations, Volatile Composition and Sensory Profiles of Godello Musts and Wines

“…Previous studies reported data on the effects of irrigation on physiology and yield response of vines in this site [7,19]. In summary, rain-fed vines showed more negative midday stem water potentials than those irrigated; whereas yield and cluster weight were similar among treatments (Table 2).…”

“…These findings contrasted with the results from the current study likely because of the different cultivar/rootstock combination and climate conditions. In fact, soil water availability was adequate for bud-break and the development of leaf surface in our study [7,19], so no differences in grapevine metabolism were expected.…”

“…No stress conditions were observed in 2014. In summary, rain-fed vines showed more negative stem water potentials than those irrigated, especially from veraison onwards; these differences were more marked in 2013, the warmest growing season [19]. This explains the absence of significant differences among treatments in yield.…”

“…In summary, water was applied for 59, 46 and 34 days in 2012, 2013 and 2014, respectively, at a rate of 1.5 h per day. Average irrigation depths were 1.14 mm and 1.54 mm for DI and SDI, respectively [19]. Agricultural practices were the same for all treatments, except for irrigation.…”

“…Several variables were measured over the study period for characterizing the water status, vegetative growth and yield of vines in each treatment. Both methods and results about these determinations are out of the scope of this report and have been described elsewhere [7,19]. However, we summarized the most important findings in the Results and Discussion section.…”