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  • The salt tolerance of vegetable paprika varieties
    39-45.
    Views:
    157

    In our experiments, we have chiefly tested the salt sensitivity of sweet pepper varieties. In cold forcing, 0.3 1/plant nutrient solutions of different NaCI content were given twice weekly. EC of the nutrient solutions containing 0.25% Volldünger Linz complex fertilizer was made up to 6, 10, 14 and 18 mS/cm, respectively, by 2.51/9.17/17.97/26.76 g/m2 doses of pharmacopeal NaCI every week. The solution used for the control treatment contained Volldünger only (EC 4.4 mS/cm). Irrigation was made with pure water (EC 0.6 mS/cm) when necessary.

    The varieties chosen for the experiments were the following: Feherözön, HRF F1, Syn. Cecei (of white, conical fruit), Boni (of white, blunt, infolded fruit), Titan F1 (of pointed, hot fruit) and Pritavit F1 (of tomato shaped fruit).

    In general, the symptoms caused by NaCI treatments (with doses higher than 10 g/m2 weekly) have been the following:

    • They have reduced the leaf area, the height of the plants, the total and the early yield, the number of fruit set per square meter, the average weight of the fruit (and, in some measure, fruit length, too) and the thousand seed weight.
    • They have increased the calcium and the chlorine content of the leaves and fruits and the dry matter content of the fruits.
    • They haven't affected the dry matter content of the leaves, the nitrogen, phosphorus and potassium content of the leaves and fruits, and the germinating ability of the seed.
    • The effect on stem diameter and on seed production per fruit has been contradictory in some cases.

    The effects of the intermediate treatments haven't been explicit in several cases.

    The results of the examination of cuticular secretion have indicated the increase of the sodium and chlorine content of the leaves. This can be important in field growing where the rainwater may wash out a part of sodium and chlorine from paprika leaves.

    The hot, pointed variety and the tomato shaped paprika haven't shown clearly higher salt tolerance than the varieties of white fruit colour.

  • Optimization of sample preparation for determination of antioxidant parameters from one grape berry
    93-97.
    Views:
    185

    Berry quality is an important issue in wineprocessing, however evaluating characteristics in a single berry level is very complex. The Phenolic compound analysis is more challenging because of the limited amount of material and a mixture of skin, pulp and seed. No clear protocol exists for evaluating these compounds from single berries. The aim of our investigation was to develop such a protocol. Single whole grape berries samples were homogenized in 20 replicates by 5 different methods. The most effective method was when berry was placed in a mortar and was crushed with a pestle under liquid nitrogen until seeds were clearly visible. Seeds were then taken from the mortar and crushed between two stainless steel plates with a hammer, and returned to the mortar without residues. Homogenization continued until the sample had a powdery appearance. The homogenized samples were taken for further analysis such as total polyphenols, total anthocyanin contents and total antioxidant capacity. Our results demonstrate that single berries could be processed and that the homogenates were suitable for taking chemically uniform subsamples.

  • Eicosapentaenoic acid production by Phaeodactylum tricornutum under different culture condition
    133-136.
    Views:
    117

    Phaeodactylum tricornutum UTEX 640 strain of microalgae was screened under different culture conditions for their capacity to produce eicosapentaenoic acid (EPA) the most abundant polyunsaturated fatty acid (PUFA). In our experiments, the effect of sodium chlorid, nitrogen source, phosphate, initial pH, as well as the CO2 content of the medium on production of the eicosapentaenoic acid (EPA) by P. tricornutum were investigated. The EPA content of biomass was enhanced by the low pH of the medium, with increased concentrations of B17 vitamin and nitrate, and also with decreasing concentrations of sodium chlorid. The EPA is most likely associated with polar (membran) lipids and the role of EPA appears to be involved with membran permeability in microalge. The synthesis of phospholipids, enhances the EPA content of the cells, as expected. The maximum EPA yields were observed under optimum culture condition 43 — 48 mg/g of dry cell weight.