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  • Postharvest methyl jasmonic acid and hot water can reduce the internal breakdown and quality loss of apricot fruit at shelf life
    31-34.
    Views:
    241

    The aim of this study was to investigate the postharvest effect of methyl jasmonic acid (MJ) and hot water on internal break-down and quality loss of apricot fruit under shelf life conditions. Cultivar Flavor cot apricot fruit were used to treat with water as control treatment, with 0.2 mmol/L MJ and with hot water 35 oC for 5 min. Fruit were stored at room temperature and were examined every 2 days for internal break-down and quality loss. Results showed that treated fruits with MJ and hot water showed the lowest weight loss and the highest firmness during all assessment times. Control fruits showed losing of customer acceptance from the day 2 of shelf life and then decreased dramatically to approximately loss all the acceptance at day 8. The SSC showed sever reduction in untreated fruit after day 6 at shelf life. Total phenol content reduced and polyphenol oxidase (PPO) increased in all assessment times for all treatments. Meanwhile MJ showed the best values for phenol content and lowest PPO activity. The results supported the idea of using some elicitors like methyl jasmonic and hot water treatments to enhance shelf life of apricot fruit.

  • Effect of water supply on nutrient transport in grapevine varieties
    64-68.
    Views:
    142

    The effect of water supply on availability of macro nutrient elements (N, P, K) by the plants in the soil and their transport in the plants were examined. In a field experiment two grapevine varieties characterized by higher (White Riesling B 7) and lower (Kövidinka K 8) water requirement were compared on the basis of N, P, K concentrations of leaf blades, petioles and berries. A different water supply of the vineyard was achived by striped coverage of the soil with plastic foil to exclude rainfalls from the beginning of May to ripening. Humidity of the soil decreased as the vegetative phase advanced. Soil cover resulted in 25-30% decrease of the water content in the soil at flowering but this difference gradually disappeared till veraison (i.e. the start of intense growth of the berries). The water consumption in the White Riesling B 7 plantation was more intensive. Mobility and availability of N, P, K in the soil was restricted by water exclusion (i.e. plastic soil cover) at flowering. Nitrogen was slightly affected, whereas P and K were in a higher extent. Comparing the transport of nutrient elements in the two varieties, leaf blades of Kövidinka K 8 contained less N and more P and K than White Riesling B 7 at flowering and more N and P and less K at ripening. Water deficiency inhibited K accumulation in the berries of White Riesling B 7, while this effect did not appear in Kövidinka K 8.Water exclusion decreased the yield of White Riesling B 7 already at lower bud loading, the yield of Kövidinka K 8 was affected only at higher bud loading. The higher yields of the treatments in Kövidinka K 8 plantation support the superior performance of this variety under the hot and dry climate of the Hungarian Great Plain.

  • Relation between the germination and infection ratio on Sida hermaphrodita L. Rusby seeds under hot water treatment
    117-121.
    Views:
    202

    Sida hermephrodita or virginia mallow is a perspective perennial herb in the Malvaceae family able to yield a biomass crop through between ten and twenty years. Additionally, the plants have a lot of uses and benefits for instance it can use it as a fodder crop, honey crop, ornamental plant in public gardens. It has favorable features like fast growing and resistance against the disease and climatic fluctuations, etc. Sida is in base stage of domestication therefore has a serious disadvantage the low and slow germination as a big part of wild plants. Due to the expressly low germination percent the need of seed showing of driller is should tenfold, 200 thousand seed/acre instead of 10-20 thousand what is not available and expensive Therefore practical purposes of our research of seed physiology was to increase the seed germination percent in a disposable ,basically wild Sida population. We examined two factors relating to seed germination percent and seed germination power during our research: the influence of hot water treatment and the effect of exogenus or endogenus infection of seed. However, in our germination tests, utilizing scarified seeds with hot water (65, 80 and 95 oC), 29,33 to 46% germinated of the seeds collected from the population of S. hermaphrodita in Debrecen. The average germination for all season was 5-10 % wihitout treatment and rised using hot water up to almost 50%. When physically scarified used, the oldest seeds showed the best germination (46 %) after the hot water operation in spite of the previus studys (Spooner 1985; Chudik et al. 2010; Doliński R. 2009.). We discovered that there are a distinguished close relationship between the seeds collecting time and the infection, as well as germination percentage. Thus, 2009 season was the most favourable in case of contamination (control:17,33 and 80 oC treatment:0%) as well as germination percent. It could be concluded that, the best season for our findings was 2009 due to autumn harvest of Sida seeds. In our oppinion, the autumn harvesting should be the best time to overcome the problem of the low germination and high infection percentage.

  • Evaluation of fruit tree waterstress condition and transpiration with heat fl ux sensors
    leaf area index, evapotranspiration, water stress
    Views:
    232

    In this study the transpiration properties and response to heat stress of Granny Smith and Jonagold apple species were measured. The examinations were set at an orchard near to Debrecen. The chosen trees were two years old, without fruits, in 20l container, placed in the mixture of mulch matrix, wood chips and sawdust and grown at the same climatic conditions. One of the most important goals was to determine the leaf area of the trees which is a basic data for transpiration modeling. Leaf area was larger (signifi cance level p<0.05) in the upper part of the canopy to achieve larger photosynthetic surface. Jonagold species with less leaf number (–18% compared to Granny Smith) reached almost the same canopy area, than Granny Smith, due to larger leaf area of Jonagold. Another aim was to measure the transpiration rate of the apple trees. The transpiration measurements were carried out by sap fl ow meter. Only a small transpiration difference can be found between species. During the investigation time there were wet and cool as well as dry and extremely hot periods. In the case of dry and extreme hot periods the transpiration is decreased, which causes decrease in transpiration and enhanced the water stress of trees.

  • Effects of salinity stress induced by hot spring water on tomato growth, yield and fruit quality under hydroponic cultivation in Japan
    23-28.
    Views:
    159

    The objective of this research was to test hot spring water as a source of salt to improve tomato quality under the hydroponic system. This research was conducted at Yamagata University, in Japan from February to July 2017. Salt stress was induced using salts of hot spring wastewater collected from Yupoka Onsen (Tsuruoka, Japan). The treatments were EC 2, 4, 8 12, and 16 mS/cm which were arranged in a Randomized Complete Block Design (RCBD) with five replications. Tomato plants were grown at EC 2 until flowering and then subjected to different EC concentrations until harvesting. The data were collected on plant growth parameters and fruit quality. Fruits were harvested at the red stage until the 5th truss. The results showed that fruits' Soluble Solids Content, organic acid, Nitrate contents and Sugar: Acid ratio increased significantly at EC 16 mS/cm and in the upper trusses compared to EC 2 and in the lower trusses. In contrast, fruit weight significantly decreased at EC 16 mS/cm and in upper trusses. Leaf thickness, size and SPAD, and specific leaf weight significantly declined at EC 16 mS/cm and upper leaves compared to EC 2 and in lower leaves. Plant height started to decline significantly after three weeks of treatment at EC 16 compared to EC 2.

  • Industrial-scale plantlet production by seed priming and nursery tray seeding method in Sida hermaphrodita L. Rushby
    71-74.
    Views:
    219

    Virginia mallow (Sida hermephrodita Rushby), Malvaceae family, is a perspective perennial herb able to yield a biomass crop through the last two decades. In our previous studies, we examined two factors relating to seed germination percent and seed germination power during our research: the influence of hot water treatment and the effect of exogenous or endogenous infection of seed. Following these recognition we modifi ed our technique, in such a way that we fractionated the seeds based on their fresh weight / or relative density before we carried out the treatment. When we fi ltered the fl oating seeds on the surface of water, the hot water treatment was performed considerably better on the sink seeds after separation. Therefore, by this special priming process we were able to reach 80% germination capacity of Virgina mallow seeds under laboratory conditions (26 oC without illumination). From all nurseries tray methods preliminary results, it is clear that, Sida seeds, which were treated with these methods, gave the best growing rate for industrial uses.

  • Phytoplasma diseases of grapevine and the possible measures to control them
    37-43.
    Views:
    301

    Phytoplasmas are a special group of phloem-living pathogens in several plant species. Grapevine yellows (GY) is a term for phytoplasma diseases occurring on Vitis vinifera and inducing the same or very similar symptoms and causing severe losses worldwide. Flavescence Dorée (16SrV) phytoplasma (FD, species name: ‘Candidatus Phytoplasma vitis’) is considered a quarantine pest in several countries due to its epidemic character and high economic loss it provokes. The leafhopper Scaphoideus titanus is the univoltine and monophagous vector of FD. Bois noir disease caused by stolbur (16SrXII-A) phytoplasma (species name: ‘Candidatus Phytoplasma solani’) is described under different disease names in different countries. Hyalesthes obsoletus (Cixiidae) is the only proved polyphagous vector of BN. However, distribution of BN disease is increasing also on those areas where H. obsoletus is not prevalent or only in a very low number. Therefore the presence of other vectors cannot be concluded. The ‘Tuf-a’ type Stolbur phytoplasma is associated with stinging nettle (Urtica dioica) and the tuf-b type one to field bindweed (Convolvulus arvensis). There are only preventive control measures against phytoplasmas: the use of pathogen-free propagating material, hot water treatment of propagating material, as well as control of vectors and weeds. S. titanus can be efficiently controlled by insecticide treatments. However, in case of H. obsoletus, insecticides are not effective due to the biological characters and feeding habits of the vector.Weed control can reduce H. obsoletus specimen and their abundance to a certain extent. Extensive research is needed on wild hosts of GY phytoplasmas especially on BN phytoplasma and its vectors to the better understanding of their epidemiology.

  • Relation of sour cherry blooming dynamics and meteorological variables
    17-23.
    Views:
    264

    The aim of our research was to identify the role of weather parameters in the development of the start date and length of blooming. In order to achieve this, we examined how meteorological conditions of a particular year influence the start date and length of blooming in different years (dry, wet, cool, hot, sunny, cloudy). The meteorological parameters were the following: maximum temperature, minimum temperature, average temperature, precipitation, length of sunlight, difference of daytime and nightime temperatures, potential evaporation-PET, Huglin-index,Winkler-index, climatic water balance which can be calculated as a difference of precipitation and potential evaporation. In this study we wanted to find out whether early start of blooming results in a longer blooming period or if there is a generally faster blooming period when blooming starts later. Based on the results we can say that early start of blooming resulted in extended blooming period for three sour cherry varieties at the examined production sites. The start of blooming showed the closest relation with the difference of average daytime and nightime temperatures of the 30-day period prior to blooming. Significant relation was also detected with the thermic indexes as well as with maximum temperatures, climatic water balance and the degree of potential evaporation.We examined how weather 30 days prior and during blooming influenced the length of phases. Results showed that precipitation prior and during blooming is in significant relation with the length of blooming. We detected significant relation between daytime and nightime temperature differences and the length of blooming. The nature of the relation indicates that blooming periods were shorter in case of increasing temperature differences.We found that shorter blooming lengths occurred when maximum temperatures averaged between 13.5–14.5 ºC 30 days prior to blooming when examining the relation between blooming length and maximum temperature. If the average of maximum temperatures was below 13 ºC or exceeded 15 ºC during this period, then we could calculate with a blooming period longer than ten days. We proved that little precipitation and high temperature accelerates physiological processes, therefore we could calculate with an accelerated blooming and shorter blooming period.

  • The salt tolerance of vegetable paprika varieties
    39-45.
    Views:
    171

    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.

  • Fruit drop: II. Biological background of flower and fruit drop
    103-108.
    Views:
    350

    The most important components of fruit drop are: the rootstock, the combination of polliniser varieties, the conditions depending of nutrition, the extent and timing of the administration of fertilisers, the moments of water stress and the timing of agrotechnical interventions. Further adversities may appear as flushes of heat and drought, the rainy spring weather during the blooming period as well as the excessive hot, cool or windy weather impairing pollination, moreover, the appearance of diseases and pests all influence the fate of flowers of growing and become ripe fruits. As generally maintained, dry springs are causing severe fruit drop.

    In analysing the endogenous and environmental causes of drop of the generative organs (flowers and fruits), the model of leaf abscission has been used, as a study of the excised, well defined abscission zone (AZ) seemed to be an adequate approach to the question. Comparing the effects active in the abscission of fruit with those of the excised leaf stem differences are observed as well as analogies between the anatomy and the accumulation of ethylene in the respective abscission tissues.

  • Bacterial diseases of grapevine
    45-49.
    Views:
    398

    Grapevines are affected by three major bacterial diseases worldwide, such as bacterial blight (Xylophilus ampelinus), Pierce’s disease (Xylella fastidiosa) and crown gall (Agrobacterium vitis). These bacteria grow in the vascular system of their host, thus they invade and colonize the whole plant, independently on symptom development. Latently infected propagating material is a major factor in their spreading. Therefore the use of bacteria-free planting stock has a basic importance in viticulture. Today several innovative diagnostic methods, mostly based on polymerase chain reaction, are available to detect and identify bacterial pathogens of grapevines. For production of bacteria-free plants, the use hot water treatment followed by establishment of in vitro shoot tip cultures is proposed.