Academic literature on the topic 'Grape vine'

I. Chennin Blanc 107-cm bilateral cordon spaced 3.6 × 2.4 m, 1119 vines/ha, 14 spurs with 32 buds/vine. Yields were 8.8 t·ha-1 in the third leaf; 9.7 in the fourth, and 12.8 the 5th year, 1990, at the Jane Terrell Vineyard, Navasota, Tex. II. Cabernet Sauvignon with a two-trunk 122 cm bilateral cordon spaced 3.3 × 1.2 m, 2445 vines/ha with 48 buds/vine. Yields were 9.7 t·ha-1 for 1994 through 1997 at the mechanically harvested Newson Vineyard, Plains, Tex. III. Le Noir with a 91-cm trunk and a two-cane canopy; spaced 3 × 2.1 m, 1536 vines/ha, with 14 buds/vine. Yields were 13.3 t·ha-1 in 1996 and 11.2 in 1997 at Messina Hoff Vineyard, Bryan, Tex. IV. Merlot/110R with a 45° slanting cordon, 30 cm at south to 152 cm at north, spaced 1.5 × 1.5 m, 4308 vines/ha with 10 spurs and 20 buds/vine. Yield of 10.8 t·ha-1 in the third leaf, 1997, at Wolf Vineyard, Valley View, Tex. Four very different canopy systems were successful; the ideal system is yet to be determined.

A “terroir” is a cultivated ecosystem in which the vine interacts with the soil and the climate. The soil influences vine development and grape ripening through soil temperature, water supply and mineral supply. Soil temperature has a significant effect on vine phenology. Limited water supply to the vines restricts shoot and berry growth, which is critical for reaching a suitable grape composition to produce high-quality red wines. Secondary metabolites, like polyphenols (anthocyanins, tannins) and aroma compounds or their precursors, are impacted in particular by vine water status. Among nutrients vines pick up from the soil, nitrogen plays a key role. Nitrogen influences vine vigor, yield, berry size and grape composition. Low nitrogen supply stimulates the synthesis of polyphenols, while it can negatively impact certain aroma compounds in grapes and wines. Over the past decades, tools have been developed to quantify terroir parameters. Vine water status can be assessed by means of carbon isotope discrimination measured on grape sugar (so-called δ13C). Vine nitrogen status can be assessed with the measurement of Yeast Available Nitrogen (YAN). In this way, terroir parameters can not only be measured but also mapped. Ideally, vineyards should be established in areas where soil temperature (relative to air temperature), soil water holding capacity (relative to rainfall and potential evapotranspiration) and soil nitrogen availability are optimum for the type of wine which is intended to be produced. Terroir expression can, however, be optimized by choosing appropriate plant material, and via vineyard floor management, fertilization and other management techniques.

The present investigation was carried out during 1994 and 1995 seasons on `Roomy Red' grape vines cultivated in Minia and Beni Suef governates to study the effect of Dormex and/or overcropping on `Roomy Red' grape vines. Bud opening, number of clusters per vine, as well as the yield and its physical and chemical properties, were studied. Results indicated that Dormex overcame the irregularity of bud opening. At the same time, bud opening preceded the control by about 4 weeks. The percentage of bud opening, fruit set, as well as the number of clusters per vine, were increased. On the other hand, over-cropping had a vice versa effect on the previous parameters as compared with the control. Results also indicated that onion was of less effect than berseem in this concern.

Each of the grape cultivars [Vitis species, (L) Batch], `Concord', `Himrod', `Challenger', `Reliance', `Glenora', `Moored', planted June 1983, and `Mars' planted Spring, 1987, was trained to the 4-cane Kniffin (KN) and the Geneva Double Curtain (GDC) systems. Yield per vine, pruning weight, number of nodes, cluster weight, number of berries per cluster, berry weight, and percent soluble solids were recorded. Vines from `Reliance' trained to the KN system produced fruit with significantly higher percent soluble solids than did vines trained to the GDC. No significant differences in percent soluble solids were observed between the two training systems for the other cultivars. `Concord' produced more kg/vine of pruning weight when trained to the KN system than when trained to the GDC. Pruning weight did not differ significantly between the two training systems for the other cultivars. Cultivars more productive (yield/vine) on the GDC trellis were `Concord', `Himrod', `Reliance' and `Moored' whereas `Challenger' was more productive when vines were trained to the KN system. No differences between the two training systems were observed for `Glenora' or `Mars'.

The influence of soil type and preparation on vine development and grape composition was investigated in a 50 ha estate located in Saint-Emilion (Bordeaux, France) and planted predominantly with Merlot. Part of the vineyard was planted down the slopes and another part of the vineyard was planted on terraces, where soils were profoundly modified through soil preparation. Grape composition (berry weight, sugar, total acidity, malic acid and pH), vigor (pruning weight), vine nitrogen status (Yeast Available Nitrogen (YAN) in grapes) and vine water status (δ13C) was measured at a very high density grid of 10 data points per hectare. Water deficit was globally weak over the estate because of high soil water holding capacity whereas vine nitrogen status was highly variable. Vine vigor and grape composition were predominantly driven by vine nitrogen status. On terraces, where soils were deep, due to invasive soil preparation, water deficits were particularly small or non-existent and vine nitrogen status was highly variable. Grape quality potential was medium to low, except in places with low nitrogen status, but at the expense of low yields. On parcels planted down the slopes water deficits were recorded because vine rooting was limited by compact subsoils. Vine nitrogen status was homogeneous. Grape quality and yield were medium to high and relatively homogeneous. When possible, downhill plantations are to be preferred over terraces because in the latter vine yield and quality parameters are highly variable because of massive soil movements prior to plantation.

Background and aims: Seasonal differences in vine yield need to be managed to ensure appropriate fruit composition at harvest. Differences in yield are the result of changes in vine management (e.g., the number of nodes retained after harvest) and weather conditions (in particular, temperature) at key vine development stages. Early yield prediction enables growers to manage vines to achieve target yields and prepare the required infrastructure for the harvest.Methods and results: Bunch mass data was collected during the 2016/17, 2017/18 and 2018/19 seasons from a commercial vineyard on the Wairau Plains, Marlborough, New Zealand (41o2’23”S; 173o51’15”E). A Bayesian growth model, assuming a double sigmoidal curve, was used to predict the yield at the end of each season. The accuracy of the prediction was investigated using the Monte-Carlo simulation for yield prediction at various growth stages assuming different prior information.Conclusion: The results show that the model is sensitive to prior assumption and that having a non-informative prior may be more beneficial than having an informative prior based on one unusual year.

The grape yield per vine of cv. Cabernet Sauvignon (Vitis vinifera L.) was evaluated on the basis of digital image processing of vine part. Digital camera was mounted on tripod and used for taking photos of 1 x 1 m portions of canopy. The Adobe Photoshop software was used to analyse image for the colour counting of the blue pixels of grape in the quadrant region. The actual yield was obtained from the photographed vines by hand harvesting of sampled portions. Linear regression was used for calculation of the correlation between blue pixels and grape weight. The relatively strong relationship between blue pixels and grape weight (R2=0.91) was obtained. Based on these results, we can recommend this simple technique for yield forecasting.

Grape is one among the most delicious, refreshing and nourishing fruits of the world. It is one of the earliest fruits grown by man. The berries are a good source of sugars and minerals like Ca, Mg, Fe, and vitamins like B1, B2, and C. Grape has so many uses and is so unique that no fruit can challenge their superiority. Crop load is the most important factor affecting yield and cluster quality as well as vine vigor of both seeded and seedless varieties. Hence, an optimum canopy size and bunch number per vine are to be maintained for achieving better fruit Quality which warrants proper balancing between vigour and capacity. The pruning requirement of different varieties differs as per their growth behaviour. Therefore, variety-specific standardization of pruning is essential for any grape cultivars for harnessing potential yield and quality. In this view, it is essential to get scientific information on the pruning requirement of grapes. Pruning all the matured canes to fruit bud level, as adopted by local grape growers results in more exploitation of reserved food material leading to loss of vigour, quality and early setting of senility in vines. Heavy bearing of vines results in poor quality fruits with low TSS and high fruit acidity.

In the cool and humid climate of the northeastern United States, vegetation is typically maintained between the rows of wine grape (Vitis vinifera) vineyards, but the area directly beneath vines is conventionally kept bare using herbicides or cultivation, to reduce competition for water and nutrients. Yet with rising concerns of herbicide resistance, environmental contamination, and soil erosion, alternatives to maintaining bare ground in vineyards should be considered. In warmer and more arid climates, using cover crops as an alternative to bare soil has sometimes resulted in reduced vine growth and yields. In more cool and humid climates, like in the northeastern United States, where conditions can promote excessive vine growth, replacing bare soil with under-vine cover crops was hypothesized to improve vine growth characteristics and fruit quality from reducing excessive vigor. This study compared three annual under-vine cover crops of resident vegetation (RES), buckwheat (BW) (Fagopyrum esculentum), and annual ryegrass (ARG) (Lolium multiflorum), planted in the 1-m-wide strip directly under vines at the start of each growing season, against the conventional weed-free under-vine row maintained with glyphosate. The experiment was established in 2011 and repeated in 2012 and 2013 in a 20-year-old block of ‘Riesling’ wine grapes (clone 198 on S04 rootstock) in a commercial vineyard in the Finger Lakes region of New York State. Harvested grapes were fermented in duplicate using standard white wine procedures. Among the four under-vine treatments, no significant differences were found in measures of vegetative growth, yield, petiole nutrient concentrations at veraison, or predawn and midday stem water potentials. Under-vine treatments were not found to significantly affect soil organic matter, aggregate stability, and nutrient concentrations. Juice characteristics were also not significantly different among treatments. In this study, the mature vines in this rain-fed ‘Riesling’ vineyard likely had a well-developed and extensive rooting system that was able to overcome any competition effects for water or nutrients from the comparatively shallow root systems of the annually established cover crops. Without any induced competition in the conditions of this study, under-vine cover crops had no effects on vine growth, yield, or juice characteristics when compared with conventional herbicide use in the under-vine row. When multidimensional scaling (MDS) analysis was used to determine differences in aroma among wine treatment replicates, treatments were found to significantly impact the perceived aromatic properties of the wines, even though no measures of growth or juice characteristics were affected. Using under-vine vegetation may be a viable alternative to conventional herbicide use for vineyard floor management in mature wine grape vineyards in cool and humid climates.

Suckering is the process of removing the suckers that grapevine trunks put out in the spring. Suckering by hand is costly and time consuming and requires constant bending down, getting up and making repetitive motions. The mechanical removal of suckers with rotating scourges can damage the vine plants. Chemical suckering is a limiting factor for wine grape growers interested in sustainable and/or organic agriculture. The aim of this research was to test flaming as an alternative method to vine suckering. A three-year experiment was conducted on a 10-year-old Sangiovese vine (775 Paulsen rootstock). The treatments consisted of flame suckering at different phenological stages, hand-suckering and a no-suckered control. Data on the number of suckers, grape yield components, and grape composition were collected and analysed. The results showed that flaming significantly reduced the initial number of suckers. This effect on the suckers was highest when the main productive shoots of the vines were at the 18-19 BBCH growth stage. Flame-suckering did not affect grape yield components and grape composition. Future studies could investigate the simultaneous use of flaming for both suckering and weed control.

Mestrado Vinifera Euromaster - Viticulture and Enology - Instituto Superior de Agronomia - UL / Institut National D'Etudes Superieures Agronomiques de Montpellier
Estimating a Vineyard’s leaf area is of great importance when evaluating the productive and quality potential of a vineyard and for characterizing the light and thermal microenvironments of grapevine plants. The aim of the present work was to validate the Lopes and Pinto method for determining vineyard leaf area in the vineyards of Lisbon’s wine growing region in Portugal, with the typical local red grape cultivar Trincadeira, and to improve prediction quality by providing cultivar specific models. The presented models are based on independent datasets of two consecutive years 2015 and 2016. Fruiting shoots were collected and analyzed during all phenological stages. Primary leaf area of shoots is estimated by models using a calculated variable obtained from the average of the largest and smallest primary leaf area multiplied by the number of primary leaves, as presented by Lopes and Pinto (2005). Lateral Leaf area additionally uses the area of the biggest lateral leaf as predictor. Models based on Shoot length and shoot diameter and number of lateral leaves were tested as less laborious alternatives. Although very fast and easy to assess, models based on shoot length and diameter were not able to predict variability of lateral leaf area sufficiently and were susceptible to canopy management. The Lopes and Pinto method is able to explain a very high proportion of variability, both in primary and lateral leaf area, independently of the phenological stage, as well as before and after trimming. They are inexpensive, universal, practical, non-destructive methods which do not require specialized staff or expensive equipment
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La Flavescence dorée est une maladie contagieuse et incurable de la vigne détectable sur les feuilles. Le projet DAMAV (Détection Automatique des MAladies de la Vigne) a été mis en place, avec pour objectif de développer une solution de détection automatisée des maladies de la vigne à l’aide d’un micro-drone. Cet outil doit permettre la recherche des foyers potentiels de la Flavescence dorée, puis plus généralement de toute maladie détectable sur le feuillage à l’aide d’un outil multispectral dédié haute résolution.Dans le cadre de ce projet, cette thèse a pour objectif de participer à la conception et à l’implémentation du système d’acquisition multispectral et de développer les algorithmes de prétraitement d’images basés sur les caractéristiques spectrales et texturales les plus pertinentes reliées à la Flavescence dorée.Plusieurs variétés de vigne ont été considérées telles que des variétés rouges et blanches; de plus, d’autres maladies que ‘Flavescence dorée’ (FD) telles que Esca et ‘Bois noir’ (BN) ont également été testées dans des conditions de production réelles. Le travail de doctorat a été essentiellement réalisé au niveau feuille et a impliqué une étape d’acquisition suivie d’une étape d’analyse des données.La plupart des techniques d'imagerie, même multispectrales, utilisées pour détecter les maladies dans les grandes cultures ou les vignobles, opèrent dans le domaine du visible. Dans DAMAV, il est conseillé que la maladie soit détectée le plus tôt possible. Des informations spectrales sont nécessaires, notamment dans l’infrarouge. Les réflectances des feuilles des plantes peuvent être obtenues sur les longueurs d'onde les plus courtes aux plus longues. Ces réflectances sont intimement liées aux composants internes des feuilles. Cela signifie que la présence d'une maladie peut modifier la structure interne des feuilles et donc altérer sa signature.Un spectromètre a été utilisé sur le terrain pour caractériser les signatures spectrales des feuilles à différents stades de croissance. Afin de déterminer les réflectances optimales pour la détection des maladies (FD, Esca, BN), une nouvelle méthodologie de conception d'indices de maladies basée sur deux techniques de réduction de dimensions, associées à un classifieur, a été mise en place. La première technique de sélection de variables utilise les Algorithmes Génétiques (GA) et la seconde s'appuie sur l'Algorithme de Projections Successives (SPA). Les nouveaux indices de maladies résultants surpassent les indices de végétation traditionnels et GA était en général meilleur que SPA. Les variables finalement choisies peuvent ainsi être mises en oeuvre en tant que filtres dans le capteur MS.Les informations de réflectance étaient satisfaisantes pour la recherche d’infections (plus que 90% de précision pour la meilleure méthode) mais n’étaient pas suffisantes. Ainsi, les images acquises par l’appareil MS peuvent être ensuite traitées par des techniques bas-niveau basées sur le calcul de paramètres de texture puis injectés dans un classifieur. Plusieurs techniques de traitement de texture ont été testées mais uniquement sur des images couleur. Une nouvelle méthode combinant plusieurs paramètres texturaux a été élaborée pour en choisir les meilleurs. Nous avons constaté que les informations texturales pouvaient constituer un moyen complémentaire non seulement pour différencier les feuilles de vigne saines des feuilles infectées (plus que 85% de précision), mais également pour classer le degré d’infestation des maladies (plus que 74% de précision) et pour distinguer entre les maladies (plus que 75% de précision). Ceci conforte l’hypothèse qu’une caméra multispectrale permet la détection et l’identification de maladies de la vigne en plein champ
‘Flavescence dorée’ is a contagious and incurable disease present on the vine leaves. The DAMAV project (Automatic detection of Vine Diseases) aims to develop a solution for automated detection of vine diseases using a micro-drone. The goal is to offer a turnkey solution for wine growers. This tool will allow the search for potential foci, and then more generally any type of detectable vine disease on the foliage. To enable this diagnosis, the foliage is proposed to be studied using a dedicated high-resolution multispectral camera.The objective of this PhD-thesis in the context of DAMAV is to participate in the design and implementation of a Multi-Spectral (MS) image acquisition system and to develop the image pre-processing algorithms, based on the most relevant spectral and textural characteristics related to ‘Flavescence dorée’.Several grapevine varieties were considered such as red-berried and white-berried ones; furthermore, other diseases than ‘Flavescence dorée’ (FD) such as Esca and ‘Bois noir’ (BN) were also tested under real production conditions. The PhD work was basically performed at a leaf-level scale and involved an acquisition step followed by a data analysis step.Most imaging techniques, even MS, used to detect diseases in field crops or vineyards, operate in the visible electromagnetic radiation range. In DAMAV, it is advised to detect the disease as early as possible. It is therefore necessary to investigate broader information in particular in the infra-red. Reflectance responses of plants leaves can be obtained from short to long wavelengths. These reflectance signatures describe the internal constituents of leaves. This means that the presence of a disease can modify the internal structure of the leaves and hence cause an alteration of its reflectance signature.A spectrometer is used in our study to characterize reflectance responses of leaves in the field. Several samples at different growth stages were used for the tests. To define optimal reflectance features for grapevine disease detection (FD, Esca, BN), a new methodology that designs spectral disease indices based on two dimension reduction techniques, coupled with a classifier, has been developed. The first feature selection technique uses the Genetic Algorithms (GA) and the second one relies on the Successive Projection Algorithm (SPA). The new resulting spectral disease indices outperformed traditional vegetation indices and GA performed in general better than SPA. The features finally chosen can thus be implemented as filters in the MS sensor.In general, the reflectance information was satisfying for finding infections (higher than 90% of accuracy for the best method) but wasn’t enough. Thus, the images acquired with the developed MS device can further be pre-processed by low level techniques based on the calculation of texture parameters injected into a classifier. Several texture processing techniques have been tested but only on colored images. A method that combines many texture features is elaborated, allowing to choose the best ones. We found that the combination of optimal textural information could provide a complementary mean for not only differentiating healthy from infected grapevine leaves (higher than 85% of accuracy), but also for grading the disease severity stages (higher than 73% of accuracy) and for discriminating among diseases (higher than 72% of accuracy). This is in accordance with the hypothesis that a multispectral camera can enable detection and identification of diseases in grapevine fields

Thesis (PhD(Agric))--Stellenbosch University, 2012.
ENGLISH ABSTRACT: A lack of defects is required for successful table grape marketing, which pre-suppose optimal vine performance, berry development and post-harvest quality. The supply of mineral nutrients affects vine development, physiology and berry quality. Despite a vast amount of research conducted over decades, there remain many unresolved issues regarding table grape vine nutrition to ensure optimal table grape quality and shelve-life. Unjustified fertilisation practices often include excessive applications of nitrogen (N), potassium (K) and calcium (Ca). A four-year field trial was therefore conducted on a sandy soil in the Paarl district of South Africa, using grafted on Ramsey, and trained to a gable trellis system. Nitrogen, potassium and calcium were applied, singular or in combination, at rates up to 300% the calculated annual nutritional requirement. The effect of these excessive applications on table grape performance under typical South African cultivation conditions was investigated for Vitis vinifera L. cv. Prime Seedless, a very early seedless table cultivar that is produced with minimum berry diameter of 18mm, with special reference to 1) vegetative growth, 2) expression of grapevine nutrient availability through foliar analyses, 3) berry nutrient accumulation patterns of this early cultivar, 4) manipulation of berry nutrient content through soil and bunch directed applications and 5) the effect of berry nutrient content on its quality. No definite vegetative growth responses (expressed as shoot length, leaf surface area and shoot mass) and leaf chlorophyll content differences were obtained for all the treatments. These results were obtained in a vineyard on a sandy soil where excessive N fertilisation caused a reduction of soil pH to detrimentally low levels and where the excessive N, K and Ca applications reduced mutual concentrations and that of Mg, in the soil. A lack of stimulation in vegetative growth may therefore be ascribed to the combined negative effect of these excessive applications on soil pH and vine nutrition. Although the N content of petioles was higher for treatments where N was applied, consistent significant increases in petiole N with N fertilisation were not observed. Petiole N concentration showed a decreasing trend throughout the season. Petiole K concentrations were significantly increased by the K fertilisation at all phenological stages. None of the K fertilisation treatments, however, succeeded to raise petiole K concentrations above the accepted maximum norms and petiole K concentration at a specific sampling stage varied significantly between the four seasons. A general decrease in petiole K concentration was found for all seasons. Calcium fertilisation did not increase soil Ca content, resulting in a lack of differences in petiole Ca concentrations between treatments. An increase in petiole Ca concentration towards harvest was obtained. Correlations between petiole nutrient concentration and berry mineral content at harvest were poor. The only way of knowing the mineral content of berries would seem to be by measuring it directly instead of deducing it from the results of leaf or petiole analyses. The dynamics of berry growth impacted on berry nutrient concentration. Early rapid berry growth, predominantly due to cell division and cell growth, was associated with the most rapid decreases in N, P and Ca concentration. Due to mobility of K and Mg in the plant, that exceeds other nutrients, the decrease in concentration of these two mineral elements was not as pronounced as that of the others. Nutrient accumulation was most rapid during the pre-véraison period, but only Ca showed a definite termination during the early ripening period. The continued inflow of N, P, K and Mg, albeit at slower rates immediately after véraison, should be taken into consideration when fertilisation is applied. As a table grape, total accumulation of each nutrient in Prime Seedless berries also far exceeded that of other cultivars studied thus far. A particular difference is that the berry flesh:skin ratio is much higher than that of previously studied cultivars, leading to higher levels of nutrient accumulation in the flesh. Slightly larger berry size was obtained for N applications and is ascribed to slight increases in early vegetative growth, allowing a better response to GA3 treatments. The use of GA3 for berry enlargement is also considered the reason why K fertilisation, resulting in increased berry K levels, did not affect berry size, as is often found for wine grapes. Higher available NO3 - in the soil on account of excessive N applications resulted in higher levels of berry N, despite sub-optimal soil pH regimes that were created by these treatments. Berry K concentration and content were increased by K fertilisation. Rapid vine K uptake and translocation to the berries seem to negate the reduced vine nutritional status as observed in petioles for situations of over-fertilisation with N. Berry Ca levels were not increased by Ca fertilisation or by bunch applied Ca. The rapid rates of berry growth, together with low rates of berry Ca uptake and Ca uptake that terminates at the onset of ripening, are assumed to be the main reasons for this result. Low levels of decay as well as a lack of consistently increased decay were obtained for N containing treatments. Nitrogen levels in the berries above which their susceptibility to fungal infection is increased, should be established. Information on specific N compounds that may lead to more susceptibility is required. Potentially increased berry browning on account of high rates of K fertilisation needs to be further investigated; indications that this may occur were observed. Neither soil applied Ca nor bunch applied Ca improved berry quality, although Ca treatments seemed to reduce decay during the only season that significant differences were obtained. The negative effect of excessive fertilisation on soil chemistry of sandy soils has again been highlighted by this study. This annuls the fertilisation, leading to inefficient fertilisation and a lack of the desired responses. As indicator of vine nutrient availability, petiole analysis, was proven unreliable and should be evaluated in parallel with soil analyses, taking seasonal variation into consideration. The danger of being only guided by published norms for leaf nutrient concentrations when establishing fertilisation practices has again been highlighted by this study. This research indicated that for a very early cultivar like Prime Seedless, nutrient accumulation dynamics can already start to change during the pre-véraison period in some seasons. This is due to different edaphic and climatic conditions as well as berry size, which leads to much higher flesh:skin ratios. Future research on table grapes would need to develop an understanding of the various factors and dynamics that determine berry nutrient concentration and accumulation of early ripening, large berry sized, seedless table grape cultivars.
AFRIKAANSE OPSOMMING: Suksesvolle bemarking van tafeldruiwe is ten nouste afhanklik van die beskikbaarheid van druiwe sonder defekte, wat ‘n direkte verband met optimale wingerdprestasie, korrelontwikkeling en na-oes kwaliteit inhou. Voorsiening van minerale voedingstowwe beïnvloed die stok se groei, fisiologie en korrelgehalte. Ten spyte van ‘n oorweldigende hoeveelheid navorsing wat oor dekades reeds gedoen is, is daar steeds onopgeloste kwessies aangaande bemesting van tafeldruiwe vir optimale druifgehalte en houvermoë. Die gevolg is onoordeelkundige bemestingspraktyke wat o.a. aanleiding gee tot oorbemesting met stikstof (N), kalium (K) en kalsium (Ca). ‘n Vier-jaar-lange veldproef is gevolglik op ‘n sandgrond in die Paarl distrik (Suid-Afrika) onderneem deur gebruik te maak van Vitis vinifera L. cv. Prime Seedless geënt op Ramsey en op ‘n dubbel-gewel prieelstelsel opgelei is. Stikstof, K en Ca is alleen, of in kombinasie, toegedien teen hoeveelhede gelykstaande aan 300% van die wingerd se jaarlikse behoefte. Die effek van hierdie oormatige toedienings op tafeldruif prestasie onder Suid-Afrikaanse verbouingstoestande is ondersoek, met spesiale verwysing na 1) vegetatiewe groei, 2) uitdrukking van voedingstofbeskikbaarheid deur blaarontledings, 3) die voedingstof akkumulasie patrone van korrels van hierdie vroeë kultivar, 4) manipulasie van korrel voedingstofinhoud deur grond en trosgerigte toedienings en 5) die effek van korrel voedingstofinhoud op kwaliteit. Die doel van die proef was om bemestinspraktyke van Prime Seedless, ‘n baie vroeë pitlose tafeldruifkultivar met ‘n minimum korrelgrootte van 18 mm, te verfyn. Deur die akkumulasie patrone van die druiwe uit te klaar is daar ook ondersoek ingestel of oestyd en na-oes gehalte deur oormatige toediening van voedingstowwe affekteer word. Geen duidelike verskille betreffende vegetatiewe groeireaksies (uitgedruk as lootlengte, blaaroppervlaktes en lootmassas) asook verskille in blaar chlorofilinhoud is vir die behandelings verkry nie. Hierdie resultate is verkry in ‘n wingerd op ‘n sandgrond, waar oormatige N-bemesting aanleiding gegee het tot grond pH verlagings tot die peil van nadelige vlakke. Verder het die oormatige N, K en Ca toedienings wederkerige verlagings in konsentrasies, asook op dié van Mg, in die grond teweeggebring. Die tekort aan vegetatiewe groeiresponse op die behandelings kon dus toegeskryf word aan ‘n gekombineerde effek van die oormatige toedienings op grond pH en voedingstofbalanse. Hoewel die N-inhoud van bladstele hoër was vir behandelings wat N toediening ingesluit het, was daar nie konstante toenames in die vlakke verkry nie. Bladskyf N-konsentrasie het afgeneem deur die loop van die groeiseisoen. Vir alle fenologiese stadiums was bladskyf Kkonsentrasies betekenisvol verhoog deur K-bemesting. Nie een van die Kbemestingsbehandelings het egter daarin geslaag om bladskyf K inhoud vir enige monstertyd bo die algemeen aanvaarde maksimum norms te lig nie. Verder het bladskyf K inhoud by ‘n spesifieke fenologiese stadium ook betekenisvol tussen seisoene verskil. Die K-inhoud van bladskywe het afgeneem met verloop van die seisoen. Kalsiumbemesting het nie die grond se Ca inhoud deurgans verhoog nie, wat dus die tekort aan verskille in Ca konsentrasies tussen die behandelings verklaar. ‘n Toename in Ca konsentrasie en korrel Ca inhoud is vanaf set tot oes waargeneem. Swak korrelasies tussen bladskywe se voedingstofinhoude en korrels se voedingstofinhoude is verkry. Die enigste manier waarop korrels se voedingstofinhoude dus afgelei kan word, blyk te wees deur direkte bepaling daarvan. Voedingstofinhoude van korrels is deur groeipatrone daarvan beïnvloed. Vroeë korrelgroei, hoofsaaklik a.g.v. seldeling en selgroei, het met die vinnigste afnametempo van N, P en Ca gepaard gegaan. As gevolg van die hoër beweeglikheid van K en Mg in die plant in vergelyking met ander voedingstowwe, was die afname in konsentrasie van hierdie twee elemente nie so groot soos vir die ander nie. Voedingstofakkumulasie was die vinnigste in die periode voor deurslaan. Slegs Ca het ‘n beeïndiging van opname aan die einde van hierdie periode getoon. Die voortgesette opname van N, P, K en Mg, alhoewel stadiger kort na deurslaan, moet in ag geneem word wanneer bemesting toegedien word. Vir hierdie kultivar het die totale opname van elke bemestingstof dié van die ander kultivars wat tot hede bestudeer is, ver oorskry. ‘n Spesifieke verskil is ‘n baie hoër vleis:dop verhouding as wat vir ander kultivars verkry is. Dit gee aanleiding tot baie hoër vlakke van voedingstofakkumulasie in die vleis. Effens groter korrelgroottes is verkry waar N toedienings gemaak is. Dit word toegeskryf aan klein toenames in vroeë vegetatiewe groei, wat dus beter reaksie op GA3 behandelings tot gevolg gehad het. Die gebruik van GA3 vir korrelvergroting word ook beskou as die rede waarom K-bemesting, wat tot hoër vlakke van K in die korrels aanleiding gegee het, nie korrelgrootte, soos by wyndruiwe, bevorder het nie. Hoër NO3 - in die grond (water), na aanleiding van N toedienings, het aanleiding gegee tot hoer vlakke van N in die korrels. Dit het plaasgevind ten spyte van sub-optimale grond pH wat deur die oormatige N toedienings veroorsaak is. Korrel K konsentrasie en -inhoud is deur K-bemesting verhoog. Vinnige opname en translokasie van K na die korrels het ook geblyk die rede te wees waarom die verlaagde voedingstatus van die stokke a.g.v. oorbemesting met N nie die korrels se K inhoud geaffekteer het nie. Die vinnige groeitempo van die korrels, tesame met lae vlakke van Ca opname, asook korrels se Ca opname wat tydens rypwording ophou, word as die redes vir die tekorte aan behandelingseffekte beskou. Lae vlakke van bederf, asook ‘n tekort aan betroubare tendense dat bederf deur Nbemesting verhoog word, is verkry. Daar moet vasgestel word of daar N vlakke in die korrels is waarbo hul vatbaarheid vir swaminfeksies verhoog word, en of daar spesifieke N verbindings is wat die korrels meer vatbaar maak vir bederf. Indikasies dat K-bemesting interne verbruiningsvlakke verhoog het, regverdig verdere ondersoek. Korrelkwaliteit is nie deur grond- of trosgerigte toedienings bevoordeel nie. Die negatiewe effek van oormatige bemesting op die chemiese samestelling van sandgronde is weer deur hierdie navorsing uitgelig. Dit lei tot oneffektiewe bemesting en ‘n tekort aan die verlangde effekte. Blaarontledings blyk onbetroubaar te wees as aanduiding van voedingstof beskikbaarheid. Dit moet evalueer word saam met grondontledings en ook seisoenale variasie in ag neem. Die gevaar om slegs deur gepubliseerde norme gelei te word wanneer bemestingspraktyke bepaal word, is weer deur hierdie navorsing uitgelig. Voorst is daar in hierdie navorsing gevind dat voedingstof akkumulasiepatrone van ‘n baie vroeë kultivar soos Prime Seedless alreeds voor deurslaan begin verander a.g.v. omgewingstoestande en korrelgroei wat tot ‘n veel hoër vleis:dop verhouding aanleiding gee. Toekomstige navorsing op tafeldruiwe behoort die faktore en dinamika wat voedingstofkonsentrasie en -akkumulasie in korrels van vroeë, groot korrel, pitlose tafeldruifkultivars beïnvloed verder te ondersoek.

La masse de la baie est le résultat de l’effet intégré de plusieurs facteurs. La recherche a été dessinée afin d’étudier l’effet simultané des facteurs majeurs influençant la masse et la composition de la baie, de les hiérarchiser selon leur degré d’impact à des échelles différentes, de séparer leur effet direct et indirect sur la composition du raisin et de comparer le profil de vins élaborés à partir de petites et grosses baies. L’étude a été conduite sur deux sites expérimentaux, localisés dans les régions de Saint-Emilion (France) et Alcamo (Italie), pendant les années 2014 et 2015. Sur le premier site, les vignes sont plantées sur deux types de sols, tandis que sur le deuxième, deux traitements hydriques étaient appliqués. A l’échelle intra-parcellaire, l’état hydrique de la vigne représente le facteur le plus important, tandis que l’effet du nombre de pépins par baie n’est pas significatif. Des résultats opposés sont obtenus lorsque les relations sont étudiées à l’échelle de la grappe et de la plante. A large échelle, les facteurs impactent directement et indirectement la composition du raisin et les petites baies produisent des moûts et des vins plus concentrés. A l’inverse, à l’échelle de la grappe et de la plante, la masse de la baie n’influence pas la composition du raisin. Seule la concentration en anthocyanes est significativement liée à la masse à toutes les échelles. Cette relation est particulièrement évidente sous conditions hydriques limitantes. Un déficit hydrique augmente le ratio pellicule/pulpe, indépendamment de la masse de la baie. Petites et grosses baies d’une parcelle ayant une condition hydrique homogène, tendent à avoir un profil similaire
Final berry mass is the result of the integrated effect of several factors. They also influence berry composition. The present work was designed to study the simultaneous effect of major factors influencing berry mass and composition, to hierarchize their impact at different scales, to distinguish their direct and indirect effect on berry composition and to compare the profile of wines made from large and small berries. The study was carried out simultaneously on two vineyards located in the Saint Emil ion (France) and Alcamo (Sicily) areas, during 2014 and 2015. On the first site, vines were planted on two soil types, while on the second site two different irrigation treatments were applied. Depending on the scale, some factors homogeneously impacted the berry mass and composition. At the intra-parcel scale, vine water status represented the most impacting factor, while berry seed number did not have significant effect. Opposite results were obtained when the investigation was carried out at the intra-bunch and intra-plant scales. At large scale, factors impacted directly and indirectly berry compounds and grape juices and wines produced from smaller berries were more concentrated. Neither at intra-bunch, nor at intra-plant scales, berry size effect on juice composition was significant. Only anthocyanin concentration was related to berry size at all scales. This fact was particularly obvious in berries produced under limited water conditions. Water deficit increased the skin to flesh ratio, independently of berry size. This means that small and large berries, produced from a single parcel with homogenous water uptake conditions, tend to have similar enological profiles

Organic mulches and cover crops mulched in situ were assessed for their effects on B. cinerea primary inoculum and disease levels in inflorescences at flowering and/or bunches at harvest. Organic mulches were used to enhance biological degradation of vine debris to reduce levels of B. cinerea primary inoculum the following season. Four mulch types (anaerobically and aerobically fermented marc (grape pressings), inter-row grass clippings and shredded office paper) were applied under ten-year-old Riesling vines in a ten-replicate randomized block design in New Zealand over two consecutive years. Plastic mesh bags, each containing naturally infected vine debris, were placed under vines on bare ground (control) and at the soil-mulch interface, in winter (July) 2003 and 2004. In each year, half the bags were recovered at flowering (December) and the remainder at leaf plucking (February), for assessment of B. cinerea sporulation from the vine debris and debris degradation rate. Bait lamina probes, which measure soil biological activity, were placed in the soil-mulch interface three weeks before each of the two bag-recovery dates in both years and were then removed and assessed at the same times as were the bags. All mulches led to a reduction in B. cinerea sporulation. This reduction was significantly correlated with elevated rates of vine debris decomposition and increased soil biological activity. Over both years, compared with the controls, all treatments gave a 3-20-fold reduction in B. cinerea sporulation, a 1.6-2.6-fold increase in vine debris degradation and in the two marc and the paper treatments, a 1.8-4-fold increase in activity of soil organisms. The mulches also altered vine characteristics and elevated their resistance to B. cinerea through changes to the soil environment. Functional soil biological activity, as measured by Biolog Ecoplates and bait lamina probes, was increased 2-4 times in the two marc and paper treatments, compared with the control, an effect relating to the elevated soil moisture and reduced temperature fluctuations under these mulches. Soil nutrient levels and the C:N ratios were also affected in these treatments. The mulched paper lowered vine canopy density by up to 1.4 times that of the other treatments, an effect which probably led to elevated light penetration into the canopy and consequent increased canopy temperature, photosynthesis and lowered canopy humidity. These changes to soil and vine characteristics increased grape skin strength by up to 10% in the paper treatment and sugar concentrations by 1.2-1.4 °Brix in the two marc and paper treatments. The severity of B. cinerea infections in the anaerobic marc, aerobic marc and paper treatments were reduced to 12%, 3% and 2.2% of the control, respectively, in field assessments averaged over two consecutive harvests. Cover crops mulched in situ had similar effects to those of the organic mulches, increasing soil biological activity and reducing B. cinerea primary inoculum and the severity of B. cinerea infection in grapes at harvest (2006). Inter-row phacelia and ryegrass were mulched in winter 2005 and compared with a bare ground control, under 10-year-old Chardonnay vines in a ten-replicate randomized block design. Functional soil biological activity increased by 1.5-4.5 times in the two cover crop treatments compared with the control, an effect possibly related to elevated soil moisture in these treatments. This increase in soil moisture and soil biological activity increased vine debris degradation, reduced B. cinerea primary inoculum on the debris and decreased B. cinerea severity at flowering (December 2005) and harvest (April 2006). These results show the potential of organic mulches and cover crops mulched in situ to enhance soil ecosystem services and improve the sustainability of viticultural practices.

Vineyards in the Mid-Atlantic often have large, vigorous vines that can be costly to manage and produce inadequate fruit for wine production. Dense canopies increase the incidence of fungal disease, require greater allocation of resources to manage, and inhibit fruit development. The primary objective of these studies was to determine effective vine-size modification treatments that would optimize fruit quality, while reducing labor and chemical control. Research factors included root manipulation, under-trellis ground cover, and rootstock. Treatment levels were root bag (RBG) or no root manipulation (NRM); under-trellis cover crop (CC) or herbicide strip (HERB); and one of three rootstocks: 101-14, Riparia Gloire, or 420-A. Effects of these treatments were measured in two experiments: Experiment I compared combinations of all three treatments, while Experiment II explored the individual effects of root restriction using root bags of varying volumes. Root restriction consistently demonstrated the ability to reduce vegetative growth and vine water status. In the first experiment fruit-zone photosynthetic photon flux density (PPFD) was increased by 234% in RBG vines. Timed canopy management tasks indicated that RBG canopies required about half the labor time of NRM canopies. Anthocyanin concentration and total phenolic content were increased by 20% and 19% respectively in RBG fruit. CC increased fruit-zone PPFD by 62%, and increased soluble solids and color compounds. The 420-A rootstock reduced potassium uptake, resulting in lower must potassium concentration. Results demonstrated that these treatments significantly reduce vegetative growth in a humid climate, decrease management labor, and produce higher quality fruit.
Master of Science

The influence of rootstock and canopy density on grape berry composition was investigated over the summer of 2003-2004 on a commercial vineyard at Waipara, North Canterbury. This experiment was designed to investigate the influence of rootstock and canopy density on the acid composition, potassium (K) content and final pH of harvested fruit (Pinot Noir AM 10/5 Lincoln Selection). The trial block consisted of eight rootstocks laid out to an 8 x 8 latin square, each plot consisting of five vines of the same rootstock. Two canopy treatments were overlaid the block (down whole rows, assigned randomly, four rows to each treatment); one treatment allowed to grow naturally, in the other treatment the canopy was thinned removing double burst shoots and laterals. The bunch numbers were adjusted in the Unthinned canopy treatment (UCT) to match the Thinned canopy treatment (TCT). Information was gathered to assess: the canopy size and density (Pinot Quadrat Leaf Layer and Percent Gaps and canopy porosity), the plant yield (and berry size, berries per cluster, cluster weight, clusters per plant), plant K levels at flowering and veraison (from petioles and leaf blades) and berry composition at harvest (soluble solids (as brix), K, titratable acidity (TA), tartaric acid concentration, malic acid concentration and pH). The trial area was non-irrigated on clay loam soils and viticultural management was to best commercial practice. It was found that although rootstock influenced the levels of K in the plant and in the juice at harvest, the level of K in the juice did not influence pH in this experiment (range of rootstock juice K: 808 ppm to 928 ppm, l.s.d. = 75 ppm). The level of tartaric acid concentration in the juice was found to be the dominant influence on the level of pH in this experiment (rootstock pH range: 3.21 to 3.39, l.s.d. = 0.05). The juice concentration of tartaric acid was influenced by both rootstock (rootstock range 4.0 to 4.7 g/L, l.s.d = 0.4) and canopy density (UCT = 4.1, TCT = 4.7, l.s.d. = 0.4), decreased shading positively increasing the level of tartaric acid. The malic acid concentration in the juice was positively influenced by increasing canopy density (UCT = 4.7 g/L, TCT = 4.1 g/L, l.s.d = 0.4) and this played a minor role in the determination of pH in this experiment; an influence of rootstock on the level of malic acid concentration was found. The malic acid concentration strongly influenced the determination of TA (UCT = 11.0 g/L, TCT = 10.2 g/L, l.s.d = 0.5); tartaric acid concentration had a minor influence on the recorded TA. Attempts to characterise the influence of rootstock on malic acid, tartaric acid and pH were inconclusive. Rootstock was found to influence the canopy variables measured in this experiment and the recorded average plant yield. Crosses of Vitis rupestris were found to exhibit the most canopy vigour and those derived from Vitis berlandieri and Vitis riparia the least. The Canopy treatment did not show an influence over yield but the rootstock was found to influence plant yield, through the numbers of berries set in a cluster and the final harvest cluster weight. The influence of rootstock on pH may be described by the influence it exerts on canopy growth and yield but this was thought unlikely. Further research is required to describe the nature of the rootstock influence on K, malic acid, tartaric acid and pH.

O objetivo deste trabalho foi comparar a resposta da videira a dois tipos de poda (poda em vara e talão; e poda em cordão bilateral com talões) e duas dotações de rega (rega deficitária tradicional e rega melhorada) em duas castas: “Touriga Nacional” e “Antão Vaz”. Avaliou-se a resposta das plantas a estes fatores em termos de produtividade e qualidade das uvas (grau Baumé, acidez total, índice de polifenóis totais e antocianas). O ensaio foi realizado em Reguengos de Monsaraz, em cerca de 600 videiras de cada casta, sendo deixada uma carga de gomos idêntica para os dois tipos de poda. Após o tratamento estatístico, concluiu-se que para a casta “Touriga Nacional” a produção foi cerca de 10% superior para a poda em talões, que registou maior número de cachos embora com menor peso médio. A rega aumentou ligeiramente o peso do cacho na poda em vara e não teve efeito neste parâmetro na poda em talões. Em termos de qualidade não se registaram diferenças significativas em relação à poda. A rega melhorada subiu o teor de açúcar e a acidez total, tendo pouco efeito a nível de índice de polifenóis totais (IPT) e antocianas. Na casta “Antão Vaz” a produção foi cerca de 25% superior na poda em vara face à poda em talões. Estas diferenças devem-se a um maior número de cachos na poda em vara, que também registaram maior peso médio. Os diferentes tipos de poda não se traduziram em diferenças significativas na qualidade (registou-se uma subida no teor de açúcar e descida da acidez total devido à menor produção para a poda em talões). A rega melhorada subiu o teor de açúcar e desceu a acidez total para os dois tipos de poda; Study of the pruning system and irrigation management in two grape varieties in Reguengos de Monsaraz region ABSTRACT: The objective of this work was to compare the vine response after two pruning systems (cane pruning and spur pruning) and two deficit irrigation treatments (traditional deficit irrigation and improved irrigation) in two grapes varieties: “Touriga Nacional” and “Antão Vaz”. The plants response to these factors in terms of yield componentes and grape quality (sugar content, total acidity, total polyphenol index and anthocyanins) was evaluated. The test was carried out in Reguengos de Monsaraz, in about 600 vines of each variety, leaving an identical load of buds for both pruning systems. After statistical treatment, it was concluded that for “Touriga Nacional” variety the yield was approximately 10% higher for spur pruning, which registered a higher cluster number although having a lower average weight. Irrigation slightly increased the cluster weight in the cane pruning and had no effect on this parameter in spur pruning. In terms of quality there were no significant differences in between pruning systems. The high water availability increased, in grapes, the sugar content values and the total acidity, having a low impact on the total polyphenol index (TPI) and in anthocyanins. In the “Antão Vaz” variety the yield was about 25% higher in the cane pruning compared to spur pruning. These differences are due to the greater clusters number in cane pruning, which also recorded higher average weight. The different pruning systems did not translate into significant differences in quality (there was an increase in the sugar content values and a decrease in the total acidity due to lower yield for spur pruning). Improved irrigation incresed, in grapes, the value of the sugar content and lowered the total acidity for both pruning systems.

The use of Precision Agriculture in the vineyard chain has had a strong evolution over the last years, due to the need to risks control derived by pest and climate change. The great variability of the specific environment, dimension and infrastructure have determined more research development than market ready technologies, in comparison with what is happened in tillage crops. In viticulture, pest and climate dangerous event risk control, with IoT technologies is the core of innovation, then there is the vigour control of the vines by monitoring an agronomical management. For the high value chain of wine traceability and sustainability, key indexes are fundamental. Digital and high tech territorial platforms are essential to increase PA technologies acquisition in grape and wine value chain.

AbstractResearch demonstrates that positive emotions contribute to students’ greater engagement with the learning experience, while negative emotions may detract from the learning experience. The purpose of this study is to evaluate the effect of a computer-based training program on the emotional status and its effect on the performance of two students with learning difficulties: a second-grade student of a primary school with Simpson-Golabi-Behmel syndrome and a fourth-grade student of a primary school with learning difficulties. For the purpose of this study, the “BrainHQ” web-based cognitive training software and the mobile app “AffectLecture” were used. The former was used for measuring the affective state of the students before and after each intervention. The latter was used for improving students’ cognitive development, in order to evaluate the possible improvement of their initial emotional status after the intervention with “BrainHQ” program, the possible effect of positive/negative emotional status on their performance, as well as the possible effect of high/poor performance on their emotional status. The results of the study demonstrate that there is a positive effect of emotion on performance and vice versa and the positive effect of performance on the emotional status and vice versa. These findings suggest that the affective state of students should be taken into account by educators, scholars and policymakers.

Rooted plants can often be obtained and transferred from one environment into another either in order to increase the number of vines producing a specific grape in a vineyard or to introduce a new variety or propagate a new cultivar. It has been found that some vines can be grown from hardwood cuttings. The technique of hardwood cutting involves removing a cane (Figure 4.1, a and b) from a successful vine once the vine has gone dormant for the winter, trimming it appropriately, and then planting it in well-fertilized soil either with or without growth stimulants (i.e., phytohormones, vide supra). It is clear that the conditions of planting, reported by various sources, are a function of variety and terroir. Interestingly, it appears that the cutting, which may have been grown on a rootstock different from the variety of grape produced, will produce roots that are true to the variety of grape. Once the vine, from seed, grafting, or cane begins to grow, it must be “trained” so that its growth can be monitored and successful grape crops harvested. The training includes proper spacing of vines and the establishment of a trellis system or posts for each vine. Trellis systems are set up during the first or second year of the growth of the vine since harvesting of grape crops before the third year is rare. The trellis, which will need to bear the weight of the vine and grapes, is built much like a fence. Thus, the row of grape vines is held up by end posts at the end of the row and line posts about 20 feet apart between the ends. Usually, there is a line post for every two or three vines with some species needing more space than others. Generally the end posts are thick treated wood, concrete, or steel and are strongly anchored. The line posts are thinner, and the trellis itself is made of twelve (12) gauge or heavier wire with the number of wires a function of the weight to be supported and the height to which the grapes are to be grown.

Tillage practices in viticulture are very important, with major effects on quantitative and qualitative production, on vines phenology and stages of growth. In this study the aim was to identify the most appropriate vineyard floor management, located on flat land or mild slopes, with medium or high soils fertility. The research was carried out during 2011–2013 in the vineyard of the BUASVM Didactic Station from Timisoara and focusing exclusively on several variants of soil maintenance in order to replace the need for manual labor. Leaf area was estimated by concentric circles method and sugar concentration was evaluated by refractometry. Total acidity in must and wine was determined by titration. Grape yield was estimated by bunches counting and weighing, for each variety and productive potential (kg ha-1) was appreciated by multiplying the average yield per vine with the number of vines per hectare. Statistical analysis was performed using GraphPad Prism 6. Performance of Burgundy variety for superior red wines group and Silvania table grape variety – with a medium ripening, were analyzed in the experiment. For both Burgundy and Silvania varieties the sixth variant (V6–bare soil by tillage middles row (tractor and rotary hoe)/rotary hoe undervine (tractor and adjustable offset rotary tiller) registered the highest grape yield during the research. The lowest grape yield fulfils to the seventh variant of vineyard floor management. Burgundy variety had the average must sugar content of 195 ± 4.27 g l-1 and that of the leaf area of 7.09 ± 0.58 m2 while in Silvania variety the average of grape must acidity was 4.66 ± 0.35 g l-1 H2SO4 and the leaf area of 7.42 ± 0.51 m2/vine. Between must sugar content and leaf area, in Burgundy and Silvania variety has been established a significant positive linear correlation (r = 0.94 ***) and (r = 0.88 **; p <0.001) respectively, variables being virtually indistinguishable.

The latest generations of interspecies grapevine hybrids are increasingly attracting the attention of producers, especially due to increased production safety and reduced use of pesticides. The economic effect is evident, and the obtained product follows modern world trends in the production of safe food. The aim of this paper is to examine the technological characteristics of three varieties of Morava, Johanniter and Riesling Rhine in the conditions of the Banja Luka region. Varieties Morava and Johanniter belong to the group of interspecies hybrids. The mentioned varieties were compared with the Riesling Rhine variety, which belongs to the varieties of the noble vine and represents the standard for the comparison of the given varieties. The focus of the research was on examining the yield of varieties, the characteristics of grapes and berries, as well as the quality of grapes. Elements of the mechanical composition of grapes and berries were made according to the method of Prostoserd (1946), and the characteristics of grape juice (% Brix, titratable acidity and pH value) according to official OIV methods. The variety Johanniter had the lowest weight of grapes (73.85 g), and the variety Morava had the highest weight (128.61 g). The varieties Johanniter and Riesling Rhine had a relatively high sugar content in grape juice (22.1%), while the variety Morava had a high sugar content (25.93%).