Effects of limited irrigation water volumes on near-isohydric ‘Montepulciano’ vines trained to overhead trellis system

The thermal increase, due to the changed climatic context, is leading to marked variations in the yield and quality of the grapes and causing an increase in the use of water resources in several viticultural areas. Nevertheless, in some environments, rainfalls are scarce and there is no water availability. In this study, we compared the impact of low water irrigation volumes (DI, replacement of 70% of crop evapotranspiration) with respect to non-irrigated vines (NI), on the physiological, yield and qualitative performances of near-isohydric variety ‘Montepulciano’, trained to overhead trellis system, which requires a high-water supply. The stomatal conductance and photosynthesis values, in basal and median leaves, were higher in DI vines. All NI leaves sufered water stress, showing in the youngest leaves (position 20 and 25 along the main shoot) higher carbon isotope discrimination (δ13C) (− 25.38‰ and 25–25.77‰, respectively). At harvest, DI vines showed yield higher of 30% and 33% than NI vines in 2005 and 2006, respectively, and 18% in 2007. In environments with prolonged water shortage and low water resource, near-isohydric ‘Montepulciano’ vines, trained to overhead trellis system and irrigated with limited volumes, determined a signifcant improvement of ‘vineyard efciency’ with a yield of 19.2 t/ha with respect to 13.4 t/ha of NI vines, ensuring also more sugar content (+31%), anthocyanin concentration (+13%) and polyphenolic substances (+8%) than NI vines

Effects of shading nets as a form of adaptation to climate change on grapes production: a review

Viticulture worldwide is threatened by the environmental modification caused by climate change. Higher temperature and atmospheric CO2 concentration determine an acceleration of the ripening process, which can be detrimental to wine quality. Hence, adaptation and mitigation strategies are necessary to reduce heat and water stress and improve the qualitative production levels. Amongst all the various techniques available, shading nets represent an interesting alternative for their effects on canopy microclimate and grape production. However, these effects vary strongly depending on the intensity of the shading treatment, the timing of its application, environmental conditions, and differences in cultivar response. The reduction in photosynthetic activity can improve water use efficiency and slow down the ripening process, preserving must acidity. Phenolic compounds, which benefit from light exposure for their synthesis, are negatively affected by shading, while aromatic composition can be improved by it. Vine reserve accumulation is reduced by the lower photoassimilates production. Photoselective nets, thanks to their colour, not only reduce light intensity but also change the quality of the light spectrum reaching the canopy, thus, determining specific responses in the plants

Vegetative development and berry growth in relation to heat accumulation in Sangiovese vines subjected to double pruning at three different times

The double pruning on Sangiovese based on pre-pruning and finishing in March, April and May applied over three years, induced a postponement of phenological phases, with repercussions on the vine vegetative and berry growth trends, with greater effects, according to the delay in the time of hand follow up during the season. The phenological development, the canopy and berry growth of Sangiovese, subjected to the three different finishing dates for the final pruning, were recorded during three years (2014-2016) and related to day of the year (DOY) and seasonal heat accumulation (growing degree days, GDD). A sigmoid growth model with high coefficient determination (R2 between 0.96 and 0.99), described shoot elongation and herbaceous berry growth, showing a temporal and thermal shift according to the finishing times. Despite the chronological delay, the vines revealed similar thermal necessities. Leaf area evolution of April and May finished vines showed 2 steps: a slow initial development followed by a rapid growth phase (91- 97cm2/GDD) beginning when shoots reached 7–10 leaves. GDD allowed to obtain simple models of vegetative development and berry growth of Sangiovese vines based on thermal evolution

Efficacy of Albumin Treatment for Patients with Cirrhosis and Infections Unrelated to Spontaneous Bacterial Peritonitis

Background & aims: We performed a randomized trial to determine whether albumin should be administered to patients with infections unrelated to spontaneous bacterial peritonitis (SBP). Methods: We performed a multicenter, open-label trial in which 118 patients with cirrhosis, non-SBP infections, and additional risk factors for poor outcome were randomly assigned to receive antibiotics plus albumin (study group; n = 61) or antibiotics alone (control group; n = 57). The primary outcome was in-hospital mortality; secondary outcomes were effect of albumin on disease course. Results: There were no significant differences at baseline between groups in results from standard laboratory tests, serum markers of inflammation, circulatory dysfunction, or liver severity scores. However, the combined prevalence of acute on chronic liver failure (ACLF) and kidney dysfunction was significantly higher in the study group (44.3% vs 24.6% in the control group; P = .02), indicating greater baseline overall severity. There was no significant difference in the primary outcome between groups (13.1% in the study group vs 10.5% in the control group; P = .66). Circulatory and renal functions improved in only the study group. A significantly higher proportion of patients in the study group had resolution of ACLF (82.3% vs 33.3% in the control group; P = .03). A significantly lower proportion of patients in the study group developed nosocomial infections (6.6% vs 24.6% in the control group; P = .007). Conclusions: In a randomized trial of patients with advanced cirrhosis and non-SBP infections, in-hospital mortality was similar between those who received albumin plus antibiotics vs those who received only antibiotics (controls). However, patients given albumin were sicker at baseline and, during the follow-up period, a higher proportion had ACLF resolution and a lower proportion had nosocomial infections. ClinicalTrials.gov no: NCT02034279

Innovative vine training system as a strategy for adaptation to climate change on Verdicchio

Grape quality is endangered by thermal increase caused by climate change. Hence, the necessity to find adaptation solutions moved research activities in the last few years towards experimenting innovative management techniques. In this trial an innovative training system, called High Cane, was compared with the traditional Guyot. High Cane trained vines showed lower photosynthetically active solar radiation values at the fruiting zone, a higher number of shoots per vine and total yield. At harvest, High Cane proved to have some effects in slowing down ripening, i.e. showing lower sugar content, higher titratable acidity and lower pH. The innovative training system is a candidate to be a valid strategy for the adaptation to the effects of climate change

Vegetative development and berry growth in relation to heat accumulation in Sangiovese vines subjected to double pruning at three different times

The double pruning on Sangiovese based on pre-pruning and finishing in March, April and May applied over three years, induced a postponement of phenological phases, with repercussions on the vine vegetative and berry growth trends, with greater effects, according to the delay in the time of hand follow up during the season. The phenological development, the canopy and berry growth of Sangiovese, subjected to the three different finishing dates for the final pruning, were recorded during three years (2014-2016) and related to day of the year (DOY) and seasonal heat accumulation (growing degree days, GDD). A sigmoid growth model with high coefficient determination (R2 between 0.96 and 0.99), described shoot elongation and herbaceous berry growth, showing a temporal and thermal shift according to the finishing times. Despite the chronological delay, the vines revealed similar thermal necessities. Leaf area evolution of April and May finished vines showed 2 steps: a slow initial development followed by a rapid growth phase (91- 97cm2/GDD) beginning when shoots reached 7–10 leaves. GDD allowed to obtain simple models of vegetative development and berry growth of Sangiovese vines based on thermal evolution

Post-veraison mechanical leaf removal delays berry ripening on 'Sangiovese' and 'Montepulciano' grapevines

Ripe berries often results too rich in sugar in recent years, though harvest is done in advance, thus the hypothesis of limiting berry sugar accumulation by lowering canopy carbon assimilation during ripening phase was tested in 2011 season. Post-veraison removal of the most functional leaves on the upper part of the canopy of vertical shoot positioned medium-vigour 'Sangiovese' and 'Montepulciano' grapevines was performed mechanically in a hillside vineyard established in 2006 nearby Ancona, Central Italy. Grapevines, 2.75x1.2 m spaced, were cordon trained and spur pruned. The tractor-mounted Plucker leaf stripper (Tanesini Technology, Faenza, Italy) operated on both side of the canopy on August 26, 2011 (i.e. 28 days after veraison and 34 days before harvest), when berry sugar concentration was already at 22°Brix and total acidity was still around 9-10 g/L. The leaf stripper removed from the upper part of the canopy (0.7-1.0 m above the cordon) 60 and 29% of the leaf area in 'Sangiovese' and 'Montepulciano' respectively. As a consequence, total leaf area per vine lowered by 25% in 'Sangiovese' and 14% in 'Montepulciano'. Leaf/fruit ratio at harvest lowered from 1.18 to 0.73 m2/kg in 'Sangiovese' and from 1.23 to 1.03 m2/kg in 'Montepulciano'. The significant reduction of total leaf area registered in post-veraison defoliated grapevines of both cultivars did not affect yield per vine, bunch and berry weight, total acidity and pH of the must, but lowered juice soluble solids concentration (-0.7°Brix in comparison to control in both cultivars). Post-veraison defoliation negatively affected anthocyanins and polyphenols concentration at harvest in 'Montepulciano' grapevines, but not in 'Sangiovese' ones. Thus mechanical leaf removal, quick and easy to perform late in the season to obtain grapes less rich in sugar, may be detrimental to berry colour according to genotype and should be carefully tested on black-berried cultivars before large scale application

Impact of crop control strategies on performance of high-yielding sangiovese grapevines

Climate change will require grapegrowers to develop improved viticultural practices to control vine yield and the rate of fruit maturation. The impacts of five canopy management regimens on vegetative growth, yield, and grape quality were investigated over three years, and carryover effects on vines in the fourth year were examined. Winter pruning (Wp, the control), shoot thinning (St), shoot thinning with preanthesis defoliation (St+Dpa), shoot thinning with preveraison defoliation (St+Dpv), and shoot thinning with preveraison defoliation plus cluster thinning (St+Dpv+Ct) were applied to Sangiovese vines from 2011 to 2013. Neither St nor St+Dpv changed yield or grape quality compared to Wp. The St+Dpa treatment reduced leaf area and yield by 33% compared to Wp and St and led to increased sugar concentrations and a carryover effect into 2014 that reduced vine capacity. A management strategy that combines shoot thinning with preanthesis defoliation, which will increase sugar concentrations and suppress yield, offers the strongest potential for long-term regulation of vine yield and grape quality. However, in a nonirrigated vineyard of medium vigor, Wp, St, and St+Dpv could be used to achieve yield and fruit quality levels that meet defined thresholds while reducing costs in respect to other additional interventions such as Dpa or Ct