Search Results

You are looking at 1 - 10 of 105 items for :

  • Refine by Access: All Content x
Clear All

process biometrical data from Vitis spp. Leaves . Am J. Enol. Vitic. 47 ( 3 ): 257 – 267 . Bodor , P. , Baranyai , L. , Bálo , B. , Tóth , E. , Strever , A. , Hunter , J. J

Restricted access

Alessandri, S., Vignozzi, N., Vignini, A. (1996) AmpeloCADs (Ampelographic Computer-Aided Digitizing System). An integrated system to digitize and process biometrical data from Vitis spp. leaves. Am. J. Enol

Restricted access

Grapevine fanleaf virus (GFLV) is the causal agent of a widespread disease that affects vineyards. Since it is difficult to culture viruses, the availability of an easy and efficient method of virus maintenance in the laboratory would be of interest to virologists. The objective of this research was to determine an adequate culture medium that promotes callus growth and permits the preservation of GFLV on Vitis vinifera tissue. Fragments of in vitro cultured leaves (25 mm 2 ), originated from Cabernet Sauvignon positive for GFLV, were cultivated on a Murashige and Skoog (1962) medium, and the callus was monitored for the presence of GFLV every two weeks using ELISA. Higher 2,4-D concentration induced a higher growth, particularly when combined with a low BA concentration. The medium enriched with 1.0 ppm of 2,4-D combined with 0.5 ppm of BA showed the best result, with the callus area reaching more than 250 mm 2 after 8 weeks in culture. ELISA absorbance observed on callus tissues during the whole period was, at least, three times higher than that observed on leaves positive for GFLV kept either in vivo or in vitro and more than 18 times higher than that of the negative control. Any remarkable difference in absorbance was recorded during the period of callus cultivation. It was concluded that the viral load on the callus was not affected during this time, suggesting that this kind of in vitro culture is an efficient method to preserve GFLV.

Restricted access

The procedure involving water and water-methanol extraction, RP-HPLC-C18 column chromatography with PDA detection was developed for determination of cinnamic acid and benzoic acid derivatives in grapevine’s dietary supplements (LV, RW, VIN, VIC, and DK) available on the Polish market. Phenolic acids were analysed before and after acidic and basic hydrolysis and identified against standards. Totalamount of studied phenolic acids determined by HPLC-PDA was compared with total polyphenols content (TPC) by Folin-Ciocalteu method. The average content of studied phenolic acids (70.54±0.21; 122.95±0.49; 87.67±0.10; 132.21±0.24; 266.78 ±0.39, and 18.16±0.09 mg/100 g d.m. (dry mass) for LV, RW, VIN, VIC, DK, and WW, respectively) were higher than the TPC (1489.91±0.39, 1648.19±0.14, 1574.38±0.33, 1643.64±0.12, 1984.75±0.97, and 715.55±0.36 mg/100 g d.m. for LV, RW, VIN, VIC, DK, and WW, respectively). The new developed method was validated for specifi city, repeatability, and accuracy and can be suitable for routine quality and quantity analysis of dietary supplements containing grape vine (Vitis vinifera).

Restricted access

The eriophyid mite Calepitrimerus vitis is a common pest in many vineyards in Hungary. Deutogynes (winter-form) of Calepitrimerus vitis in the vineyards of Szekszárd emerge from their overwintering sites in spring. Protogynes (summer-form) start to appear at the beginning of May, replacing deutogynes gradually. The process lasts until the end of May when the deutogynes disappear. The mite population increases slightly during the summer months. In August a rapid increase occurs. The maximum density of mites is reached at the middle of August or at the beginning of September, when the first deutogynes appear. The mite density declines in September rapidly and it is very low in October. The hibernation shelters are in the buds and at the cane base with the 2 year old wood. The most females are found at the cane base and in buds 1–4. In upper buds mite density gradually declines. A washing technique is described to estimate the population of Calepitrimerus vitis and useful for sampling of eriophyid mites either in summer or winter.

Restricted access

Bálo , B. ( 2018 ). Landmark-based morphometry reveal phyllometric diversity along the shoot axis of the grapevine ( Vitis vinifera L.) . Progress in Agricultural Engineering Sciences , 14 ( S1 ): 1 – 9 , https://doi.org/10.1556/446.14.2018.S1

Open access

To estimate the effects of hydroethanolic red grapes seeds extract obtained from Vitis vinifera, Burgund Mare variety, Recaş , Romania (BMR) on oxidant-antioxidant ballance, as compared to ascorbic acid, during pregnancy in rats. Thirty Wistar female rats were assigned to three groups (n=10) which were administered by gavage: Group I, 3 × 100 mg/kg body weight saline, Group II — BMR 3 × 30 mg gallic acid equivalents/kg body weight; Group III — vitamin C 3 × 100 mg/kg body weight on days 1, 7 and 14 of pregnancy. On day 21 blood samples were collected. Malon dyaldehyde, lipid peroxides, protein carbonyls, nitric oxide (as oxidative stress parameters) and hydrogen donor ability and total thiol groups (as antioxidant parameters) serum concentrations were measured. Vitamin C significantly enhanced the antioxidant capacity of plasma (hydrogen donor ability, p=0.0001; thiol groups, p=0.0001), as well as nitric oxide levels (p=0.001). The extract increased the plasma antioxidant capacity (hydrogen donor ability, p=0.001; thiol groups p=0.001) and did not elevate the nitric oxide plasma levels in pregnant rats.In conclusion, in the chosen dose, the red grapes seed extract enhanced the plasma antioxidant capacity and did not influence the nitric oxide levels in pregnant rats.

Restricted access

, 53 ( 26 ): 10034 – 10041 . 10.1021/jf0503513 OIV . ( 2009 ). OIV descriptor list for grape varieties and Vitis species , 2nd ed. Office International de la Vigne et du Vin , Paris, France . Ozturk , B. , Kucuker , E. , Karaman , S. , and

Open access

Digital seed image analysis of seed remains of three ancient vinegrape samples excavated from 15th-century sites of Hungary was conducted and compared to those of ten currently grown old grapevine varieties. Digital seed images were analysed by Fovea Pro 4.0 computer program, with the final aim to identify the ancient grapevine cultivars with a final genotype reconstruction. Discriminant analysis, XY plot and histogram analyses revealed that seeds of two archaeological samples (11–13) show the closest similarity to the currently grown old vinegrape Vitis v. vinifera cv. ‘Mézesfehér’ (sample 6). Histogram analysis of seed parameter Equiv.Diam. (cm) of the archaeological seed sample ‘Budai vár’ (sample 11) showed diverse multimodal distribution compared to the unimodal distribution of cv. ‘Mézesfehér’ (sample 6), which results indicated that cv. ‘Mézesfehér’ went through a selection through the last five centuries, which narrowed the morphological diversity of this seed character.

Restricted access

The first winter-forms (deutogyne) of the eriophyid mite Calepitrimerus vitis appear in the vineyards of Szekszárd at the beginning of August and then the mites continuously take refuge in their hibernation shelters until end of October. Most winter-forms move to the buds during September. There is no connection between the moving period length and the yearly infection. In spite of the low mite population in the years with weak infestation (1999, 2001) the movement lasts the same late, until end of October. Ratio of the mites taking refuge in hibernation shelters is the best at the beginning of the moving period in August and it is decreasing continuously until October. Considering the directions of movement to the hibernation shelters, 74.7% of the mites seek for the hibernation shelters moved down and 25.3% of the mites moved up. A new method is described, useful for practical purposes in an effort to evaluate the number of mites moving towards their hibernation shelters.

Restricted access