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  • Studies on the effects of growing substrates and physical factors in sweet pepper forcing in context with the generation of calcium deficiency symptoms
    61-65.
    Views:
    206

    In the publications available for us, exact levels of physical factors and those of the growing technology determining Ca2+ deficiency are rarely detailed. Although the influencing role of the various environmental factors (humidity, light, temperature) is known, we had only little information about their exact values which could be presented for the growing practice. Sweet pepper varieties of the same type grown in various substrates responded to the environmental factors in different ways. Our results revealed that increasing temperature of the root zone had the most significant effect on the incidence of Ca2+ -deficient fruits. Their amount, however, gave different results depending on the growing substrate. In forced sweet pepper grown in soil the proportion of Ca2+ - deficient fruits were significantly lower compared to the plants grown on rockwool. Fruits derived from forcing on perlite, in container were damaged the least by the blossom end rot deficiency symptoms. Our experimental results and technological suggestions are based on measurement results of three years.

  • Appreciation of ethrel on ripening dynamic and on the content of ingredients in processing tomato (Lycopersicon lycopersicum (L.) Karsten) varieties
    33-35.
    Views:
    164

    Tomato (Lycopersicon lycopersicum (L) Karsten) is an important crop cultivated in Hungary. Ethrel has been used to advance maturity and promote uniform ripening of processing tomato since 25-30 years in Hungary. The aims of the present study were 1) to evaluate the effects of two different ethrel concentrations on ripening rate, 2) to investigate lycopene content of different maturity stages, 3) to test the effect of ethrel on lycopene content. It is important to note that the experimental year (in July and August) was very rainy and cool. Ethrel was applied at two rates: 1500 and 3000 ppm. The results clearly indicate that Ethrel can be a useful and effective tool of maturity-enhancement, under present circumstances. Ripening concentration increased significantly by Ethrel. In spite of this, Ethrel treatments did not affect lycopene content of examined varieties significantly. The quality of tomato products are characterised by their lycopene content. Colour is highly important quality factor of food products. The range in lycopene contents from all samples evaluated was 48.7 to 113.0 mg kg-1 fresh weight. Also correlations between lycopene content and colour (a*/b*, and chroma) were investigated also.

  • Effect of maturity stage on content, color and quality of tomato (Lycopersicon lycopersicum (L.) Karsten) fruit
    41-44.
    Views:
    504

    Soluble solids (Brix°), carbohydrate, organic acid, lycopene, polyphenols and HMF content of indeterminate round type tomato Lemance F1 fruits were measured in six ripeness stages from mature green to deep red stage. Color of fruits was determined by CIELab system. The L*, a*, b* values were received directly and used to calculate from which the a*/b* and the chroma were calculated. The Brix', carbohydrate, lycopene and HMF content were the highest in the 6111 stake (deep red). Carbohydrate contents constitute nearly 50% of the Brix°. The mature green stage had the lowest acid content but in subsequent stages it was fundamentally unchanged. Polyphenol content changed little during fruit ripening. Lycopene content changed significantly during maturation and accumulated mainly in the deep red stage. Analyses showed that a*/b* was closely correlated with lycopene and can be used to characterize stages of maturity in fresh tomatoes.

  • Scheduling of irrigation in snap bean (Phaseolus vulgaris var. nanus) using canopy temperature
    89-94.
    Views:
    141

    The present paper evaluates the result of irrigation experiments carried out on snap beans sown in spring and summer and grown with and without irrigation. The experiments were run over the course of 12 years. In the average of 12 years, the yield was 2.8t ha-I for spring sown and 1.9 t ha-I in summer-sown plants without irrigation. The lowest level of profitable production, the 5.5t ha-I was reached twice in the case of spring sowing and only once in the case of summer sowing. Profitable yield production can be ensured only with regular irrigation and thus the yield may be increased by 4-5 times. In four of the twelve years we determined the canopy surface temperature of snap bean stands with and without irrigation. A Raynger II infrared remote thermometer determined the canopy surface temperature every day at 13.00 hours. The canopy temperature can well characterize the water supply of plant stands. This parameter may be used for describing the degree of drought and the water turnover of plant stands with different water supply. The positive values of foliage-air temperature differences (SDD) numerically express the degree of drought and the water supply of the crops. The results indicated that a 1 °C higher SDD value may cause 90-130 kg/ha yield loss.

  • Sustainable food production with greenhouse technologies
    99-105.
    Views:
    211

    The greenhouse fruit and vegetable production is one important area which supports sustainability. To achieve
    sustainable economy and growth, the given natural resources have to be used in a smarter, renewable way in order to avoid
    depleting them. New technologies and new methods are developed and implemented to utilize resources in more optimized way.
    Sustainable food supply is essential globally for the world, however it has to be managed and achieved on local levels. We present
    the greenhouse production market restructuring with new players. What kind of difficulties arise in the open field vegetable
    production and what benefits can be realized by the customers and producers from the covered greenhouse technology in the
    continental and desert climate? What are the technical boundary conditions to establish and operate greenhouse production in
    different regions and what are the benefits realized from local food production? As an example, we analyse Qatar’s energetics,
    climate conditions and food resources, Qatar’s food supply process and its barriers. We will show how the sustainability and
    food safety appear in Qatar’s National Strategy Plan.

  • Fruit formation dynamics in parthenocarpic cucumber (Cucumis sativus L.) in spring forcing
    111-114.
    Views:
    160

    20% of the cucumber crop of the world belongs to the parthenocarp type. Parthenocarp cucumber forcing has a great importance in Hungary, too. In our country the whole area of parthenocarp cucumber forcing was approximately 500 ha of the last years (2000-2002) and 75-85000 tons of yield has been harvested (MGYSZT, 2003). It means 15 — 17 kg/m2 as an average yield. In European forcing systems, parthenocarp cucumber is usually planted in January or February and it is harvested in spring or early summer. In Hungary cucumber forcing is the most profitable in two separate periods: spring and autumn, the reason for it is the changes of the average prices of fresh market cucumber, but spring forcing is still the most profitable. Forced cucumber cultivars are mostly parthenocarp; non-parthenocarp cultivars are grown in summer preferably. Cucumber cultivars, forced in our country, are hybrids, and 90% of them are offered by foreign seed companies (KristOfne, 1998.). The productivity of these hybrids is high and the productive period is quite short. All the mentioned details give the reason why it is important to know everything about the productivity, the dynamics of growth, and the possibilities of timing of parthenocarp cultivars, and it is also important to learn how to control all these parameters. Our spring cucumber-forcing experiment aimed to characterize of those parameters mentioned.

  • Simultaneous impact of the different water supply and year type on processing tomato yield
    79-81.
    Views:
    207

    A two year (2008 and 2009) open field experiment was conducted to study the effect of irrigation on the yield parameters and fruit components of processing tomato. Two different treatments were applied: regularly irrigated (RI), irrigation cut-off 30 days before harvest (CO), compared with unirrigated control (RF). The optimal water supply was calculated from average daily temperature. The aims of the study were to investigate the effect of different water supply on yield quantity. The regularly irrigated plant stands gave significantly higher yield, and unirrigated plants showed yield loss.Water supply had strong positive (R2=0.81) effect on marketable yield and average fruit weight (R2=0.78). Linear regression showed, that 46.5 mm more water supply caused 10 t/ha more marketable yield, and 13.4 mm more water supply caused 1 g more in the average fruit weight. The irrigation increased the Brix yield as well.

  • Relationship between flowering, fruit setting and environmental factors on consecutive clusters in greenhouse tomato (Lycopersicon lycopersicum (L) Karsten)
    111-116.
    Views:
    142

    The main season of greenhouse tomato begins late winter or early spring in the northern Temperate Zone. During this period decisive environmental factors affect flowering and fruit setting.

    In the present experiments, progress and dynamics of greenhouse tomato flowering and fruit set were examined in 1999 and 2001 spring. The beginning and the end of flowering and fruit set, the number of flowers and fruits set in each cluster were recorded. Flowering and fruit set characteristics were analysed with respect to the accumulated PAR and temperature were calculated for each cluster. One flower required 31.3 mol M-2 of accumulated PAR and 38 °C of sum temperature as an average for anthesis. One fruit required 27.9 mol m-2 of accumulated PAR and 33.3 °C of sum temperature as an average for fruit setting.

  • Effect of water supply on canopy temperature, stomatal conductance and yield quantity of processing tomato (Lycopersicon esculentum Mill.)
    13-15.
    Views:
    307

    Tomato (Lycopersicon esculentum Mill.) is one of the most extensively cultivated horticultural crops in the world.Water supply is important for yield quantity and quality. The aims of the present study were 1) to evaluate the canopy temperature and the stomatal conductance on processing tomato substances with different water supply, 2) to investigate the effect of different water supply on yield quantity. There were two irrigated treatments, one of them was the reguralry irrigated plant stand which got 333 mm water during investigated period, including the precipitation and the other was the cut off substance which means the irrigation (drip) was stopped at the beginning of the ripening process and there was a control as well which got 189 mm precipitation. The canopy temperature was measured row by row with a Raytek MX 4 type infrared remote thermometer. The stomatal conductance was measured by Delta-T AP4 type porometer. There were significant differences between the control and irrigated plants according to the water supply which was formulated the canopy values. The plants with a deficient water supply were decreased the transpiration rate, therefore its cooling effect didn’t show up. The regularly irrigated tomato plants’ yield exceeded the unirrigated ones more than twice. It is emerged from the study that the irrigation has a positive effect on the amount of the harvestable yield in this year type.