Pressure-volume analysis of two grapevine cultivars ('Kékfrankos' and 'Portugieser', Vitis vinifera L.): water deficit, osmotic conditions and their possible relations with drought tolerance

Two grapevine cultivars, 'Kékfrankos'and 'Portugieser' rafted onto Teleki-Kober 5BB were investigated during regulated deficit irrigation under greenhouse conditions. Four-year old grapevine plants in 50 L white plastic containers were examined using perlite (20 %), loamy soil (30 %) and peat (50 %) (v/v) mixtureas a substrate. Two treatments were applied: 100 % (nonstressed)and 50 % (moderately stressed) field capacity.'Kékfrankos' has a stronger tolerance against water deficit compared to 'Portugieser' on tissue level. This characteristic is mainly due to the osmotic relations and the elastic tissue properties of this variety. Higher osmotic concentration resulted in delayed turgor loss point,and thus longer cell integrity

Water relations and photosynthetic responses of Kékfrankos grapevine (Vitis vinifera L.) in two terroirs with different ecological conditions

Behaviour of Kékfrankos (Vitis vinifera L.) grapevine in two terroirs (Eger-Nagyeged–hill and Eger-Kőlyuktető) were examined during the growing season 2003. There was a close relationship between physiological responses, yield, fruit quality and terroir environmental conditions. Lower water supply in Eger-Nagyeged-hill was detected during the season due to its sloping exposure and soil characteristics. Pressure-volume curves (PV-curves) indicated that there was no osmotic adjustment in the leaves of this variety. Higher osmotic concentration was measured in the leaves of the unstressed terroirs presumably due to higher photosynthetic activity. Differences in soil water content of the 2 terroirs resulted in altered cell wall elasticity of the Kékfrankos variety. Photosynthetic production per unit leaf area and total canopy surface was also affected by available soil water content being lower in Eger-Nagyeged-hill. Physiological distinction of the vines in the 2 terroirs resulted in altered yield and wine quality. Lower yield in Eger-Nagyeged-hill is partly connected to decreased photosynthetic production of the canopy. Improved wine quality of Eger-Nagyeged-hill is due to moderate water stress having positive effect at the end of the growing season and other microclimatic factors, i.e. elevated soil temperature and better sun exposure of leaves and clusters

Investigation of the stomata size and frequency of grapevine (Vitis vinifera L.) cultivar ‘Kékfrankos’

Grapevine (Vitis vinifera L.) leaves show high morphological diversity alongside the shoot. This variability has been investigated in this study to explore the change in leaf size, leaf thickness, stomata density and stomata size among the 1st, 5th and 10th leaves on the main shoots and leaves on the laterals. Results showed that leaf size altered from the basal abaxial leaves to the middle of the shoot, while the laterals had the smallest leaves. Number of stomata also varied significantly regarding the different levels of the canopy. First leaves on the shoots had the least stomata per unit leaf area while this number increased above. In contrast with this the size, i.e. length and width of the stomata did not differ. Leaf thickness was the lowest on the leaves of the lateral shoots, while the values decreased from the 1st to the 10th nodes. These results raised the question about the ontogeny and heteroblasty of the grapevine foliage

Stability of Ampelometric Characteristics of Vitis vinifera L. cv. 'Syrah' and 'Sauvignon blanc' Leaves: Impact of Within-vineyard Variability and Pruning Method/Bud Load

Historically, grapevine (Vitis vinifera L.) leaf characterisation has been a driving force in the identification of cultivars. In this study, ampelometric (foliometric) analysis was done on leaf samples collected from hand-pruned, mechanically pruned and minimally pruned ‘Sauvignon blanc’ and ‘Syrah’ vines to estimate the impact of within-vineyard variability and a change in bud load on the stability of leaf properties. The results showed that within-vineyard variability of ampelometric characteristics was high within a cultivar, irrespective of bud load. In terms of the O.I.V. coding system, zero to four class differences were observed between minimum and maximum values of each characteristic. The value of variability of each characteristic was different between the three levels of bud load and the two cultivars. With respect to bud load, the number of shoots per vine had a significant effect on the characteristics of the leaf laminae. Single leaf area and lengths of veins changed significantly for both cultivars, irrespective of treatment, while angle between veins proved to be a stable characteristic. A large number of biometric data can be recorded on a single leaf; the data measured on several leaves, however, are not necessarily unique for a specific cultivar. The leaf characteristics analysed in this study can be divided into two groups according to the response to a change in bud load, i.e. stable (angles between the veins, depths of sinuses) and variable (length of the veins, length of the petiole, single leaf area). The variable characteristics are not recommended to be used in cultivar identification, unless the pruning method/bud load is known

INTERRELATION AMONG PRECIPITATION AND ELEMENTCONTENT OF GRAPE VITIS VINIFERA L. CV. KÉKFRANKOS, GROWN IN DIFFERENT TERROIRS

Total nutrient content of soils and quantity of potentially available part in plants are determined in this study. Main affecting factors of nutrient uptake might be the geochemical conditions of soils and the applied agro-technological methods, while the real uptake of plants can be influenced by precipitation and evaporation conditions beside the rootstock and the used grafted scions. The element content of grape berries of Vitis vinifera L. Kékfrankos cultivar was studied in identical rootstocks and scions at different production areas in Northern Hungary, during two consecutive years with somehow contrasting natural precipitation. Significant effect of the precipitation was found on the elements-uptake by the plants in general. Furthermore, it was also found, that the role of production area becomes increasingly important in grape production and quality, as well. Higher precipitation resulting greater elemental content and variability in comparison with the drier years

A ferritin szerepe a szőlő stressztűrő képességének fokozásában = The role of ferritin in enhancing the stress tolerance of grapevine

Embriogén kalluszt állítottuk elő Richter110 (alany) és Chardonnay (nemes) szőlő fajták portokajiból. Ezeket Medicago sativa ferritint (MsFerr) tartalmazó Agrobacterium vektorokkal transzformáltunk. A DNS beépülését genomikus PCR-rel ellenőriztük. Poliklonális ellenanyagot állítottunk elő, mellyel megállapítottuk, hogy a transzláció magas szintű volt, a transzkriptumból nagy mennyiségű, megfelelően processzált fehérjetermék keletkezett. A transzgenikus szőlő növények elkészültéig dohányban teszteltük az MsFerr gént tartalmazó konstrukciókat. A teljes növényeken végzett UV-B kezelés, ill. levélkorongok közvetlen oxidatív stresszre adott válaszai alapján megállapítottuk, hogy az MsFerr növények toleránsabbak voltak, mint a nem expresszáló kontrollok. Az MsFerr Richter 110 növények regenerálása, szelekciója és felszaporítása sikeres volt, az MsFerr Chardonnay növények felszaporítása azonban hajtásnövekedési problémák miatt nem sikerült. Három MsFerr Richter 110 vonalat vizsgáltunk. Gyökér stresszként fás szárú dugványok tápoldatához hidrogénkarbonátot adtunk, ami klorotikus és levél száradási tünetek okozott Ebben nem kaptunk lényeges különbséget a transzgenikus és transzformálatlan növények között. Ezzel szemben, a leveleket érő hatásokkal: paraquat, NaCl só-stressz és tBHP indukált lipid peroxidációval szemben az MsFerr expresszáló vonalak toleránsabbak voltak (kisebb stressz-indukált fotoszintézis csökkenést mutattak) mint a transzformálatlanok. | Embryogenic calli were started from anthers of Richter 110 (rootstock) and Chardonnay (scion) grapevine and transformed with Agrobacterium harbouring Medicago sativa ferritin gene (MsFerr). Genomic PCR and protein immunoblotting using a polyclonal antibody confirmed that the transcription and processing of MsFerr was successful. Regeneration, selection and propagation of MsFerr Richter 110 plants was successful, but transformed MsFerr Chardonnay plants did not grow sufficiently. Until transgenic grapevine plants became available, preliminary experiments were carried out with MsFerr expressing tobacco. UV-B irradiation of whole plants as well as treatments of leaf disks with various chemical elicitors showed that MsFerr plants were more stress tolerant than non-expressing controls. After regeneration and propagation, three transgenic MsFerr Richter 110 lines were tested. Roots of green cuttings were stressed by flooding and in this experiment transgenic plants did not show significantly higher tolerance to hypoxia/bicarbonate than non-transferred ones. Leaves, however, showed increased tolerance to paraquat, salt stress and tBHP induced lipid peroxidation: their photosynthesis was less affected by these stressors than those from non-transformed plants