Summer pruning in table grape

This paper reviews cultural practices to improve fruit quality in table grape during vegetative and reproductive seasons. Summer pruning in table grape (Vitis vinifera L.) has more effects than winter pruning, above all with regard to plant productivity and final number of bunches for harvesting. Thinning is one of the most cultural technique and it consists in the elimination of vegetative or reproductive organs in excess. Other summer canopy management techniques include leaf removal, fruit shoots positioning, shoot trimming and girdling

Combined influence of bud load and bud position along the cane on vegetative and reproductive parameters of grape cv. Grillo

Cultivar Grillo vines are characterized by problems with flower biology (the fertility of basal buds) and fructification (millerandage). In this study, to manage the variability in bunch weight with winter pruning and to program others canopy management practices (i.e. early defoliation), three different treatments of bud load were set up by leaving the cane with 3, 6 or 10 buds. The effects of bud load and cane length were studies regarding bud fertility, shoot leaf area, and the number of flowers and berries, as well as the relationship between leaf area and percentage of fruit set, leaf area/flower and percentage of fruit set, and the number of hens and chicks berries. Shoots in the distal position had higher values of fertility and inflorescences with a greater number of flowers, while no ‘apical’ effect of the buds emerged. A good relationship was found between fruit set and the number of flowers, leaf area at flowering and yield, and square centimeters/flower and percentage of fruit set. Cane length was found to be a valid tool for managing bunch weight variability; the value of the leaf area/flower can be used to program early defoliation practice carried out to manage berry set

Analisi multitemporale delle relazioni tra parametri produttivi e indice di vegetazione in viticoltura

L’efficacia degli interventi agronomici dipendono dalla capacità di programmazione in termini di tempo e intensità di intervento. Questultimi aspetti possono essere calibrati tramite una corretta conoscenza delle caratteristiche produttive e qualitative dei parametric di campo e della loro variabilità nel tempo e nello spazio. La viticoltura di precisione fornisce un supporto valido alla definizione della variabilità di campo e temporale dei parametric vegetative e produttivi. Questo lavoro sintetizza due anni di viticoltura di precisione in Sicilia, nelle campagne agronomiche consotte nel 2012 e 2013 in due aziende vitivinicole “Tenute Rapitalà” e “Donnafugata”. L’indice di vegetazione normalizzato, ottenuto da immagini in multispettrale (Rapideye) acquisite nelle fasi di allegagione, pre-invaiatura e maturazione, è stato relazionato con alcuni parametri produttivi alla raccolta (zuccheri e antociani totali) nella cultivar Nero d’Avola allevata a controspalliera. Il lavoro ha lo scopo di evidenziare la forza del legame esistente nei modelli lineari di relazione tra l’indice di vegetazione ed i parametric produttivi e mettere in evidenza: 1) l’epoca migliore per acquisire le immagini da correlare con i parametri produttivi alla raccolta; 2) se le relazioni sono significative tra gli anni oppure necessitano di ricalibrazione; 3) la trasferibilità delle relazioni nello spazio. I risultati confermano le tre ipotesi indagate per il parametro “zuccheri” alla raccolta ma non tutte per “antociani totali”. Questi risultati evidenziano comunque un possible utilizzo predittivo dei modelli di relazione rilevati da satellite e la possibilità di trasferirli nello spazio, quest’ultimo aspetto necessità però di verifiche svolte in pieno campo

Quality of Grapes Grown Inside Paper Bags in Mediterranean Area

The aim of this study was to evaluate the influence of paper bagging of grape bunches on the morphological, mechanical, and chemical characteristics of berries of three table grapes varieties as an environmentally‐friendly technique for protecting clusters from biotic and abiotic agents. Clusters of Italia, Autumn Royal, and Regal Seedless grape cultivars were bagged and compared to a not‐bagged control. Air temperature inside and outside the bags was monitored. Bunch weight and length, number of berries per bunch, berry longitudinal and transversal diameter, berry mass, number of seeds per berry (normal in size and aborted), soluble solid content, titratable acidity, and skin color by CIEL*a*b* parameters were determined on four points of each berry. Berries were evaluated using texture analysis, and the main texture profile analysis parameters were compared. The air temperatures around not‐bagged clusters were slightly higher than inside the bags. In all the cultivars under evaluation, bagged bunches were heavier compared with not‐bagged ones. In Autumn Royal and Regal Seedless, these differences were mainly owing to the higher number of berries and higher berry weight of the bagged bunches. Regarding mechanical properties, in seedless varieties, the bagging treatment increased berry hardness (related to the berry firmness) and decreased berry cohesiveness and resilience, whereas an opposite behavior was found in cv. Italia. Berry skin break force was lower in the bagging treatment in all the analyzed varieties, indicating a softer and easier‐to‐chew berry skin. The findings demonstrate that the bagging technique affected the three variety parameters to different extents. The main differences were found in the seedless varieties in terms of berry size and bunch characteristics. For all varieties, bagged bunches achieved the quality level required by the market, confirming the suitability of this technique. However, the bag industry is proposing many different bag types (differing in material, shape, color, and closing system); therefore, further studies are needed to obtain more complete and exhaustive technical information

A quasi-complete mechanical model for a double torsion pendulum

We present a dynamical model for the double torsion pendulum nicknamed PETER, where one torsion pendulum hangs in cascade, but off-axis, from the other. The dynamics of interest in these devices lies around the torsional resonance, that is at very low frequencies (mHz). However, we find that, in order to properly describe the forced motion of the pendulums, also other modes must be considered, namely swinging and bouncing oscillations of the two suspended masses, that resonate at higher frequencies (Hz). Although the system has obviously 6+6 Degrees of Freedom, we find that 8 are sufficient for an accurate description of the observed motion. This model produces reliable estimates of the response to generic external disturbances and actuating forces or torques. In particular, we compute the effect of seismic floor motion (tilt noise) on the low frequency part of the signal spectra and show that it properly accounts for most of the measured low frequency noise.Comment: 15 pages, 6 figure

Flower abscission in Vitis vinifera L. triggered by gibberellic acid and shade discloses differences in the underlying metabolic pathways

Understanding abscission is both a biological and an agronomic challenge. Flower abscission induced independently by shade and gibberellic acid (GAc) sprays was monitored in grapevine (Vitis vinifera L.) growing under a soilless greenhouse system during two seasonal growing conditions, in an early and late production cycle. Physiological and metabolic changes triggered by each of the two distinct stimuli were determined. Environmental conditions exerted a significant effect on fruit set as showed by the higher natural drop rate recorded in the late production cycle with respect to the early cycle. Shade and GAc treatments increased the percentage of flower drop compared to the control, and at a similar degree, during the late production cycle. The reduction of leaf gas exchanges under shade conditions was not observed in GAc treated vines. The metabolic profile assessed in samples collected during the late cycle differently affected primary and secondary metabolisms and showed that most of the treatment-resulting variations occurred in opposite trends in inflorescences unbalanced in either hormonal or energy deficit abscission-inducing signals. Particularly concerning carbohydrates metabolism, sucrose, glucose, tricarboxylic acid metabolites and intermediates of the raffinose family oligosaccharides pathway were lower in shaded and higher in GAc samples. Altered oxidative stress remediation mechanisms and indolacetic acid (IAA) concentration were identified as abscission signatures common to both stimuli. According to the global analysis performed, we report that grape flower abscission mechanisms triggered by GAc application and C-starvation are not based on the same metabolic pathways

Effects of artificial canopy shading on vegetative growth and ripening processes of cv. Nero d’Avola (Vitis vinifera L.)

Introduction: The biology of the grapevine (Vitis vinifera L.) is clearly influenced by the climatic conditions of the growing environment, where temperature and light play a major role in modifying plant physiology. In the scenario of climatic changes, radiative excess, correlated to the increase in temperature, can concretely subject the photosynthetic apparatus to a condition of light saturation and cause a drastic reduction in photochemical efficiency, giving rise to chronic photoinhibition phenomena. Undoubtedly, the ripening behavior also undergo evident alterations; the problem of sugar ripening, which is often strongly accelerated, is induced not only by high temperatures but also by the excess concentration of carbon dioxide (CO2), which results in a higher ripening. In addition, high berry temperatures favor a reduction in the concentration of organic acids. The reported trends indicate that the need for urgent action is closely linked to the future environmental impacts that these changes could have on the entire wine sector. In recent years, shade treatments have been applied to the vine canopy to overcome this issue. Methods: The objective of this study was to determine how artificial canopy shading affects the vines vegetative growth and the ripening processes of Vitis vinifera cv. Nero d’Avola during the 2019-2020 vegetative seasons. Three treatments were established: shading treatment with a green net (shade factor 27%), shading treatment with a white net (shade factor 32%), and untreated vines, thus naturally exposed to light radiation. Results and discussion: Artificial shading, applied at full fruit set, interfered with the microclimate of the vines, causing partial effects on the grape ripening processes. At harvest, significant differences were found between the treatments in terms of sugars, also shading treatments increased must acidity and decrease pH. Results obtained on vegetative parameters, suggest that the shading treatment delays leaf fall, with potentially positive effects on the starch accumulation on perennial reserve organs to be exploited at the following season’s sprouting. Shading significantly reduced berry size, with obvious consequences on bunch weight and yield per vine. In 2020, shaded plants showed a delay in all the phenological phases. The total anthocyanins content was not changed by the shading treatment. The results obtained confirm the importance of net coverage on the microclimate of the vines, vegetative-productive activity, and grapes quality. From this point of view, the net covering technique can be a tool for controlling grapes ripening dynamics in the context of climate change

MORPHOLOGICAL ANALYSIS OF ANCIENT GRAPE SEEDS FROM A SINK IN THE MIDDLE-AGE TOWN OF PALERMO

The archaeological excavations in Piazza della Vittoria, in the Roman-Middle Age town of Palermo (Sicily) put in light a sink 3.20 m deep and 1 square m. large, partially filled by thin organic sediments. Grape seeds (grape-stones), fish scales and few vertebrate bones have been found in specific strata sealed under a stratum chronologically attributed to Islamic Middle-Age period (a post-quem limit). The finding of well preserved grape seeds is peculiar and their study opens the opportunity to improve the actual knowledge about evolution, cultivation, use and trade of Vitis L. in the Mediterranean area. This preliminary work focuses on morphologic and morphometric analysis of the ancient grape seeds with two aims: i) systematically describe the remains collection and, ii) define seeds typology and a consequent morphotaxonomic attribution. Over 200 seeds have been carefully dry cleaned (soft brush), photographed and analyzed for total breadth (B), total length (L) and length of stalk (LS) parameters, the most efficient for typological attribution (1, 2); Stummer index has been also calculated (1). Apical notch length (AN) has been for the first time evaluated. Measurements on digital images have been performed using ImageJ 1.31 platform; morphological parameters have been assembled in a dedicated database. Descriptive analysis and linear correlations have been performed using SYSTAT 10. Analysis of variance (ANOVA) and Tukey’s HSD (5% level of significance, α = 0.05) have been applied. All the parameters approximate a normal distribution. Major variation has been observed in LS (c.v. = 35.6%) and AN (c.v. = 35.6%), while B and L showed a c.v. of 9.5% and 12.6% respectively. All the analyzed parameters behave as independent variables with the exception of a significant correlation between Stummer index and L (R2 = 0.45; y = 8.17-0.047x with y = L and x = Stummer index). This correlation reveals that Stummer index depends more from the L and not from the B parameter. On the base of LS measures three subgroups have been arbitrarily created in relationship with the LS: LS1 0.90 mm (35 seeds). Analyzing together the LS groups toward AN, we have found a proportional and significant correlation (p = 0.05) between the extremes LS1 and LS3. In the entire collection, Stummer index varies from 55.76 to 100.86; in the LS groups, the range is 68.38-97.87 in LS1, 61.02-100.86 in LS2 and 55.76-81.70 in LS3. A small group (17) of seeds has been excluded for the impossibility to measure the stalk. The analyzed ancient grape seeds show a wide range of variability for all the considered parameters, revealing a polymorphic collection. In general, the seeds have a rounded heart-like shape, with a noticeable pointy stalk and a very invaginated apical notch. This typical shape is more marked in LS3 group. On the base of LS measures, LS1 is ascribable to wild grapevines, while LS2 and LS3 seem to be ascribable neither to wild nor to cultivated autochthonous Vitis. Furthermore, these seeds differ from those already described in other archaeological horizons in Italy (3) and in France (2). The Stummer index varies highly, exceeding the known range of wild Vitis vinifera (4), although values close to 100 have been already found in wild grapevines in Spain (5) and values above 80 have been also described in Extra-European Vitis species (6). A deep evaluation of the sample, including isotopic analysis and aDNA studies, is in progress. 1) T. T. Korenčič, J. Jakše, Z. Korošec-Koruza (2008) Veget. Hist. Archaeobot., 17(Suppl. 1), S93-S102 2) L. Bouby, I. Figueiral, A. Bouchette, N. Rovina, S. Ivorra, T. Lacombe, T. Pastor, S. Picq, P. Marinval, J. F. Terral (2013) PLoS ONE, 8(5), e63195 3) C. Milanesi, F. Antonucci, P. Menesatti, C. Costa, C. Faleri, M. Cresti (2011) Interdisciplinaria Archaeologica – Natural Sciences in Archaeology, II(2), 95-100 4) A. Stummer (1911) Mitt. Anthropol. Gesellschaft Wien, 41, 283-296 5) F. M. De Toda, J. C. Sancha (1999) Am. J. Enol. Vitic., 50(4), 443-446 6) D. Rivera, B. Miralles, C. Obón, E. Carreño, J. A. Palazón (2007) Vitis, 46(4), 158-16

Update on gingival overgrowth by cyclosporine A in renal transplants

Severe gingival overgrowth is one of the most frequent side effects in renal transplant patients associated with assumption of cyclosporine A. Several associations with age, sex, dosage, duration of therapy or interval since transplantation have been hypothesized. The introduction of alternative immunosuppressant drugs have been suggested to permit better long-term transplant outcomes and a decrease in incidence of gingival overgrowth. The aim of the present paper is to summarize current knowledge regarding aetiology, pathogenesis and management of gingival overgrowth induced by Cyclosporine A