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  • Volatile constituents of Nepeta cataria L., N. glechoma Benth. and N. parviflora M. Bieb. from Hungary
    47-50.
    Views:
    122

    In the temperate zone live about 150 species of the Nepeta genus. Our investigations covered the examinations of the volatile oil containing species of the genus endemic in Hungary, Nepeta cataria and Nepeta parviflora. Latter is a relict of the ancient steppe-flora and endemic in Hungary as well. Phytochemical examination of the volatile oil containing plant material has also been carried out. Catnip growing in the Botanical Garden of PTE Department of Botany contained 0,67% volatile oil in May and 0,14% in November. Chemical character of the volatile oils were measured by gas chromatography/mass spectrometry and citronellol, citral-A, citral-B and geraniol components were identified. The composition of the oil of November samples shifted towards citronellol (65%). In both samples insecticide and repellent activity bearing compounds (+)-cis-p-menthane-3,8-diol, and (—)-trans-p-menthane-3,8-diol in 2-2.5 and 4-4.5% amount have been found. The catnip sample deriving from Germany contained a small amount of anetol, citronellol, neral, geraniol and geranial (6-13%), and possibly two isomers of nepetalactone in 23-31%.

    The Nepeta parviflora endemic in the Nagyvolgy valley near Nagykaracsony consisted of the same compounds in the investigated years (1998-2000). Its limonene, methyl chavicol, b-cariophyllene, b-selinene, b-cubebene, davanone, germacrene-D constituents have been identified. In the year 2000 different GC % of these compounds were detected in the different organs of the plants.

    The closely related species Nepeta cataria var. citriodora contained 83% citral, and the N. glechoma (= Glechoma hederacea) contained 41% a-cubebene, 20% patchoulenol, 7,7% spathulenol respectively. These compounds were identified by gas chromatography and gas chromatography / mass spectrometry.

     

  • The effects of growth regulators in proliferation of Sorbus redliana 'Burokvölgy'
    77-83.
    Views:
    204

    The Hungarian cultivar Sorbus redliana 'Burokvölgy' was proliferated on Murashige and Skoog (MS, 1962) medium with half-strength macroelements and 100 mg/1 meso-inositol, 20 g/1 sucrose, 11 g/1 agar-agar. Different combinations of kinetin (KIN), metatopolin (mT), benzyladenine (BA), benzyladenine-ribosid (BAR) and indolebutiric acid (IBA) were tested, and pH was adjusted to 5.6 every case using KOH. The cultures were incubated at 20-24 °C in 8/16 hours dark/light photoperiod for 50-52 days. The main aim of our research was to find the optimal growth regulator and its optimum concentration. Purthermore, to determine the chlorophyll contents of the in vitro propagated plants' leaves. During the proliferation, the highest number of shoots were observed in the case of using BA + IBA, and on the medium containing 0.75 mg/I BA + 0.05 mg/1 IBA 8.93 shoots were found. The addition of KIN + IBA decreased the number of shoots and increased the sizes of leaves — the widest (11.2 mm) and longest (17.8 mm) leaves were obtained on the medium containing 1.00 mg/I KIN + 0.05 mg/1 IBA. The longest shoots (36.46 mm) were found in the case of applying 0.75 mg/1 BAR + 0.05 mg/I IBA. The BA + KIN + IBA combination resulted the shortest shoots. Sometimes not only shoot regeneration but spontaneous rooting was observed during the multiplication. The highest chlorophyll content (1.569 mg/g total chlorophyll, 1.132 mg/g chlorophyll-a, 0.437 mg/g chlorophyll-b) was obtained in the presence of 1.0 mg/I KIN + 0.05 mg/1 IBA.

  • Evaluation of fruit quality parameters of Rosa taxa from the Carpathian basin
    81-87.
    Views:
    162

    From the wide range of genetic sources available in Hungary, we have chosen as objective the evaluation of those rose taxa, which — on the base of their quality and morphologic features — are suitable for selecting fruit production varieties or parent varieties for further breeding. We examined physical and inner parameters of fruits of Rosa taxa, and evaluated the correlations by mathematical statistic methods. Namely, if a correlation can be found between physical and inner parameters, fruit production value can be determined by less examinations in the future. According to our results, there is a large variability in some physical parameters (weight, diameter of fruits; weight, number of achenes) as well as in inner content values (vitamin C, glucose, fructose, K, Ca, Fe, Zn and Cu content) of rosehip, regarding production year, habitat and even the individual of examination. Twice as much ascorbic acid can be found in achene-free fruits, and nearly five times as much in their dry product as in fresh whole fruits. It was established repeatedly, that vitamin C concentrates in fruit flesh, and ascorbic acid content can be preserved better in achene-free flesh. There is no essential difference in citric acid and carbo-hydrate content of whole and achene-free rosehips. However, macro- and microelement content of whole fruits is 30-40% higher than that of achene-free fruit flesh. The connection between fresh weight and diameter, as well as achene number and seed weight of fruits can be described by the function y=axb. A significant relationship can be found in case of K-Fe, Ca-Mg, Ca-B, Ca-Mn and Zn-Cu, between fresh weight and B content of fruits. According to our examinations, fresh weight of rose species with a higher citric acid content is usually higher, while their Fe content is smaller. Glucose content of fruits of rose species is directly proportional to their Ca and Zn contents. Zn content of rose species with higher fructose content is usually smaller.

  • Evaluation of lifespan values of six tree taxa in city streets
    25-27.
    Views:
    315

    The aim of this study was to evaluate lifespan values of trees in tree-row system in the streets of Debrecen in two years (2009 and 2017). Six selected taxa (Pyrus calleryana, Acer tataricum, Sorbus intermedia, Magnolia kobus, Acer platanoides and Crataegus x lavalleei) were estimated for the following lifespan parameters: i) trunk diameter (cm), ii) tree crown size (m), iii) trunk status (in 0-5 grades), iv) tree crown status (in 0-5 grades), and v) estimated tree viability (in 0-5 grades). Our results showed that the largest were achieved for Pyrus calleryana and the lowest for Acer tataricum. The largest tree crown diameters were achieved for Acer platanoides and the lowest Magnolia kobus. The best trunk statuses by 2017 were achieved for Pyrus calleryana and the worst Crataegus x lavalleei. The best tree crown statuses by 2017 were achieved for Pyrus calleryana and the worst for Acer tataricum. The best estimated tree viability status was achieved for two taxa (Pyrus calleryana and Acer platanoides). Overall tree values were 2.73 times higher in 2017 compared to 2009. In summary, this study demonstrated the role of appropriate choice of tree taxa for a tree-row system under city street conditions.

  • Comparative study of some nutritionally important components on different cabbage (Brassica oleracea L.) genotypes
    81-84.
    Views:
    146

    Vegetables of Brassicaceae are especially important because of their inner values, which play a provably positive role in curing and preventing diseases. Cabbage (Brassica oleracea L. convar. capitata provar. capitata) is still today one of the most frequently consumed green vegetables, which is known to brake the absorption of carcinogenous substances and to obstruct cell mutation. Different cabbage cultivars were compared growing under the same circumstance. The level of different carbohydrate fractions and some biologically active quaternary ammonium compounds were determined. In all cases we analyzed the antioxidant capacity of samples characterizing the free radical scavenging capacity.

    Clearly detectable significant differences were found between the varieties tested, which appeared suitable for selecting the most precious varieties for human nutrition.

  • The effect of Ferbanat L nano-fertilizer on the growing of Petunia x grandiflora ’Musica Blue’
    107-109.
    Views:
    250

    During our experiment, the effect of Ferbanat L concentrations were examined by Petunia x grandiflora ‘Musica Blue’ production. The leaf and shoot length, number of flower buds, diameter of flowers, and the date of appearing the first buds were measured. The solution of Ferbanat L in 0.1 % concentration was the most effective on shoot length (21.7 cm). Remarkable increase was observed by the other treatment groups as well comparing to the control group (5.6 cm), the plants treated with solution of Ferbanat L 0.2% (16.5 cm) and 0.3% (14.4 cm) had significant effect as well. The nano-fertilizer had not positive effect on the other examined parameters as leaf and flower size, number of flower buds or chlorophyll content. The culture period shortened five days.

  • The effect of nectar production to the gathering behaviour of honeybees and to the foraging activity of wild bees at apple flowers
    45-57.
    Views:
    172

    Intensity of bee visitation (honeybees and wild bees), foraging behaviour of honeybees and nectar parameters (nectar production, sugar concentration, sugar content in nectars) were inspected at 18 apple cultivars for three consecutive years. Honeybee visitation was calculated to be some 3.07 bee visits at a single apple flower a day but wild bee activity was very low, only some 0.11 wild bee visits per flower per day.

    The nectar production (nectar content) of apple flowers was fairly different according to the cultivars and the nectar production (nectar content) of flowers was negatively correlated with the sugar concentration in nectar. Interestingly, at the majority of the inspected 18 cultivars the nectar production has shown minor or no changes in the morning and at the afternoon. The nectar production (nectar content) of flowers clearly encouraged the total bee activity at the inspected cultivars (r = 0.54). Bees visited abundant nectars with greater sugar concentration most intensely than lees abundant nectars with smaller sugar concentration.

    Nectar parameters, however, affected the activity of honeybees with different types of gathering behaviour in different way. More intense activity by pollen gatherer and mixed behaviour honeybees was observed at cultivars producing abundant nectar (pollen gatherers: r = 0.65, mixed behaviour: r = 0.79). The activity of pollen gatherer honeybees and of mixed behaviour bees, on the other hand, was negatively correlated to the sugar concentration in nectar (pollen gatherers: r = -0.51, mixed behaviour: r = -0.73). This can be explained by the fact that their behaviour was much more affected by the amount of pollen than by any nectar parameters. Accordingly, "mixed behaviour honeybees" should probably rather be called as "pollen gatherers with nectar load" instead of "nectar gatherers with pollen load", as widely used in literature. The activity of ineffective side worker nectar gatherers was greatly encouraged by the sugar concentration in nectar (p = 0.63), similarly to the pure (top) nectar gatherer honeybees (r = 0.72). There was a negative relationship between the nectar production (nectar content) of flowers and the activity of these behaviour classes (nectar gatherers: r = -0.47, side workers: r = -0.36).

    Concluding the findings we can state that the activity of pollen gatherers and mixed behaviour honeybees is strongly encouraged by greater nectar production (greater nectar content) of apple flowers. Their activity, however, is mostly dependent firstly on the amount of pollen. This is the reason why the sugar concentration is in a negative relationship to the activity of pure pollen gatherers and mixed behaviour bee. On the other hand, pure nectar gatherers and side worker nectar gatherers are greatly encouraged by the sugar concentration of apple nectar the amount of nectar was not a definite influence on their activity.

    Side worker honeybees occurred at each cultivar inspected, however, their ratio varied widely among cultivars. So we can draw the conclusion that, in contradiction with earlier believes, side worker nectar gathering is a general phenomenon at apple flowers. The activity of side workers depends first of all on the relative position of stamens and petals; however, low sugar concentration of nectars can probably moderate their activity but probably do not affect pollen gatherers and mixed behaviour bees.

    Wild bee visitation was very low; the wild bee species observed (Osmia cornuta, Andrena flavipes, Anthophora acervorum, Bombus terrestris, Bombus lapidarius and Halictus simplex) comprised some 3.44 per cent of the total bee visitation at apple flowers only. Wild bee visitation was in a positive correlation with the nectar production (nectar amount) of flowers (r = 0,4) and with the sugar content of nectar (r = 0.46) but it was negatively correlated with the sugar concentration in nectar (r = -0,27).

    Our result calls the attention to the importance of nectar parameters in the effective honeybee pollination of apple plantations. Most effective pollinating activity of honeybees can be expected in plantations with cultivars of high nectar production because this feature seem so encourage the activity of those behaviour classes (pure pollen gatherers and mixed behaviour bees) that are the most effective pollinating agents among honeybees.

  • The effect of timing and IBA treatments on the rooting of plum rootstock hardwood cuttings
    7-10.
    Views:
    221

    In propagation of plum by hardwood cuttings, the success of rooting is affected by several factors. Many authors deal with the timing of cutting collections, others investigate the optimal extent of hormonal stimulation. However, there is no data, as yet, about the coherence between these two factors. The aim of this experiment was to find the most advantageous condition s, with regards to both timing and IBA doses, for rentable propagation of the examined varieties. Five varieties were studied: 'INRA Marianna GF 8- 1', 'Myrobalan B', 'MY-KL-A', 'INRA Saint Julien GF 655/2' and 'Feher  besztercei'. Cuttings were collected on  seven  occasions, during  late autumn  and winter, and were treated with IBA solutions of different concentrations. The optimal dose of IBA was found to be dependent both on the variety and the actual date of cutting collection . Results are reported, along with suggestions for optimal doses and collection periods.

  • Test of the utility of apple retrotransposon insertion patterns for molecular identification of 'Jonathan' somatic mutants
    7-10.
    Views:
    197

    Up until today, apple sport mutants proved to be indistinguishable from each other and their progenitors at the molecular level using random amplified polymorphic DNA (RAPD), amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) marker techniques. This is not surprising, since the genomes of these somatic mutants differ only in one or a few small regions that affect economically important characteristics, such as improved fruit colour, size, or flavour. In most cases, these genome differences are probably caused by retrotransposons which are able to convert their RNA transcripts to DNA with reverse transcriptase enzyme prior to reinsertion, but unable to leave the genome and infect other cells. Retrotransposon insertions can alter the expression of other genes and/or the structure of encoded proteins. The sequence-specific amplified polymorphism (S-SAP) technique is capable of revealing the genetic distribution of retrotransposable elements over the whole genome. The present study used this approach to try to characterize and distinguish 'Jonathan' somatic mutants via fingerprinting, which is an unsolved problem.

  • Effect of intensity of bee visitation and the foraging behaviour of honeybees on the fruit set and yield of apple (Malus domestica Borkh.)
    31-39.
    Views:
    147

    Based on the results of our experiments, both the relative and the effective intensity of bee visitation were rather different depending on the cultivars as well as the time of the day. While it varied between relatively extreme values (40-80%) in the morning for the varieties examined, there were much smaller differences between the intensity of bee visitation at the afternoon, because the relative bee visitation attained 70-90% at each cultivar. These results showed that the differences arising from intensity of bee visitation of different cultivars should be taken into consideration more carefully in the morning in orchard planning and in estimating the number of honeybee colonies required.

    The results showed that the greatest percentage of fruit set and the highest number of viable seeds per fruit were measured on branches of those cultivars that were most frequently visited by pure pollen gatherer bees as well as by bees collecting both nectar and pollen (mixed behaviour). The effect of pure pollen gatherers and of bees with mixed behaviour was highly significant from the statistical point of view on the fruit set and the number of viable seeds per fruit.

    Those bees that were sucking nectar only from apple flowers did not proved to be effective pollinators at all. Relationship between their number and the fruit set as well as the number of viable seed per fruit were not significant because the coefficient of correlation was close to nil.

    The ratio of side worker nectar gatherers was negatively correlated with the fruit set and the seed content of fruits of apple cultivars examined at both of our experimental sites, at Mosonmagyaróvár and Feketeerdő as well. The presence of side worker nectar gatherers resulted in higher decrease of fruit set and seed content of fruits at Feketeerd6 than at Mosonmagyaróvár, especially in the morning.

    The effect of flower visiting intensity by other pollinating insects was found to be fairly variable according to the time of the day. In the morning they had no effect on the fruit set as well as on the seed content of fruits either at Mosonmagyaróvár or at Feketeerdo. However, at the afternoon, when their intensity was greater, the correlation was a bit stronger.

  • Ornamental plants in Hungary Part II. Open-ground cultivation
    143-147.
    Views:
    160

    The main fields of open ground ornamental plant cultivation in Hungary are: Woody ornamental nursery products (trees, shrubs, conifers) (950 ha cultivation area and 4-6 million plants sold per years.; Rose bushes (around 140 ha and 2-4 million bushes per year); Perennial plants (20-30 ha and 3-4 million plants per year); Dried flowers (200-250 ha of land and a production value of 5-700.000 HUF per year). The paper is discussing in detail the structure, development and tendencies of ornamental nursery production (with figures in tabulated form) and later gives shorter assessments of the present state and perspectives of the other three fields. Finally, a list is given of the Hungarian professional associations and unions, education and research centres involved in ornamental plant growing and trade.

     

  • Susceptibility of fruit of some plum and apricot cultivars to brown rot
    53-55.
    Views:
    283

    In this three-year study, incidence of brown rot (Monilinia spp.) on fruit of plum and apricot cultivars were evaluated in Kecskemét, Hungary. Results showed that most plum and apricot cultivars expressed symptoms caused by Monilinia spp, graded between 2 and 4 (10–75%) by the end of the summer in 2008–2010. Assessments on plum showed that only cultivars ‘Besztercei’, ‘Silvia’ and ‘Tuleu gras’ were partly tolerant to Monilinia spp., while the most susceptible cultivars were ‘Bluefre’ and ‘Stanley’. The most tolerant apricot cultivars were ‘Borsi-féle kései rózsa’, ‘Piroska’, ‘Pannónia’ and ‘Magyar kajszi’ while the most susceptible ones were cvs. ‘Budapest’ and ‘Mandulakajszi’. Susceptibility classes showed that only one plum (’Silvia’) and one apricot cultivar (‘Borsi-féle kései rózsa’) were available with low susceptibility.

  • The effect of day and night temperatures on apple skin colour formation
    21-25.
    Views:
    240

    The colour of fruits is considered to be an important quality indicator. Saleability greatly depends on how well covered the colour is of the specific type of fruits. It is a well-known phenomenon by growers that apples get nicer colours in one year while in other years the basically red and green colour cultivars can be differentiated only by morphological characteristic features. Cover colour is one of the phenometric variables and it is a well-known fact that significant differences can be experienced year by year. The experienced oscillation can be the cause of inappropriate water- and nutriment supply, however it can be the result of some kind of plant disease, extremely high or low temperature, setting rate above the average and outstanding fruit density. In the present examination it is postulated that the degree of cover colour is mostly influenced by day and night temperature. Therefore, our study aims to find out whether it is true or not. Cover colour belongs to those phenometric characteristic features, only the final value of which is taken into consideration; due to their nature of establishment or forming time it seems useless to follow closely the change in the time of vegetation. However, determining the start of colouring and knowing the dynamics of full colouring could carry very important information for growers. If it is possible to determine the curve describing the time change of colouring, we have a possibility to estimate it by means of enviroment variables. So it is also possible to model pigmentation in the future. Knowing this, colouring irrigation could be made more efficient in the future. For this, as a first step, it is inevitable to find out what the relationship is between the main meteorogical variables, namely day and night temperature and the difference between day and night temperature, and colour cover. In this study we summarize and show these interrelations.

  • Seasonal root development of Cabernet sauvignon grafted on different rootstocks
    61-63.
    Views:
    172

    The minirhizotron system gives opportunity to study the root development without disturbing the soil and root. We have found certified differences in root development during the year 2013 among the rootstocks grafted on ‘Cabernet sauvignon’. The number of roots varied according to the rootstocks in different depth of soil layers and also varied the development of ripeness of the root system. We conclude that root system development is affected by soil physical and chemical properties, but differences according to the rootstock genotype on the similar type of soil exist.

  • Summer pruning of sweet cherry trees and an inquiry of winter frost damages
    41-44.
    Views:
    279

    One of the most demanded research projects is the intensification of fruit production. The use of dwarfing stocks is a moderate solution as their effect is scarcely satisfactory. Climatic conditions of Hungary are continental in Eastern Europe, where Atlantic and Mediterranean effects are interacting with the continentals in a kind of basin with characters of its own. Capricious meteorological episodes are often disturbing the security of development and fruiting of trees:
    • winter frosts are damaging the cambium and fruiting structures of trees
    • late spring frosts destroy cambium and flowers
    • early autumn frosts hurt the leaves
    • excessive precipitation impairs the growing fruits
    • drought periods during the summer caused water stress disturbing water husbandry.

    Vigorous stocks still prevail in the practice, and they ought to withstand challenges of weather hazards. The strong vigour of plants delaysthe process of senescence and the tendency of getting bald, and regeneration of plants is a sign of vitality. In present research, the trees have been trained on vigorous Prunus mahaleb stocks. Summer pruning was one of the important tools of intensive growing techniques. They were compared with traditional techniques and with plastic foil protected trees observing the vegetative as well as generative growth of them.

  • Development in intensive orchard systems of cherries in Hungary
    76-86.
    Views:
    317

    High density central leader systems, the so called "spindle trees" are spreading in intensive stone fruit orchards established for hand picking in Hungary. Results of Brunner (1972, 1990) and Zahn (1967, 1996) inspired the researchers to implement their theories into practice under our climate and special soil conditions. For sweet cherry it is essential to apply an orchard system appropriate for hand picking because of the European market requirements. In intensive sweet cherry orchards two new training and orchard systems are developed and adapted to environmental conditions in Hungary based on previous inventions. The first step of the development is represented by modified Brunner-spindle, which applies the delayed heading of the central leader and the sectorial-double-pruning system from Brunner (1972), resulting intensive orchard of 600-800 trees/ha density, planted on standard vigour rootstocks. Modified Brunner-spindle trees are developed with a central leader and wide-angled branches on it. Light bearing wood is positioned on the central leader and wide-angled branches. During training, shoots for branches are bent or a sectorial double pruning is used. The growth of central leader is reduced by delayed heading, and the strong upright shoots are pinched in summer. Based upon tree size spacing of 5 m between row and 2.5-3 m between trees is recommended, tree height is around 3.5-4 m. This training system is useful for hand-picking; 60-70% of the crop can be harvested from ground. Modified Brunner-spindle is suitable for either standard or moderate vigorous rootstocks. The cherry spindle is an intensive orchard planted with 1250-2300 trees per hectare and it is recommended for sweet and sour cherries on semi dwarf to vigorous rootstocks, depending on soil fertility and quality. Trees are 2.5-3.5 m high, 75-80% of the crop can be harvested from the ground. Permanent basal scaffolds are developed on the basis of the canopy to counteract the stronger terminal growth. The tree is headed only once, after planting, from the following year the central leader grows from the terminal bud. The central leader developed from the terminal bud results moderated growth in the upper parts of the tree head. The strong upright shoots that may develop below the terminal bud are pinched to 3-4 leaves in the summer or removed entirely. The weaker, almost horizontal shoots growing from the central leader form fruiting twigs in the following year if their terminal bud is not removed. Brunner's double pruning is used only once or twice on the permanent basal branches because of its good branching effect. Trials on various rootstocks are running to find optimum spacing and fruiting wood management. The training and pruning guidelines are discussed in the paper. The average crop of bearing years is around 20-30 t/ha depending on site and cultivars. This new system is spreading in Hungary, around 70 ha sweet and sour cherry orchards are trained according to our guidelines.

  • Flowering performance of some Modern Rose Varieties in Hungary
    69-75.
    Views:
    144

    A variety trial has been accomplished to study the flowering performance of some modern roses. Blooming time and blooming intensity were studied in Hungarian and Western European varieties. 120 Floribundas, polyanthas and climbings were observed. Our work shows that valuable Hungarian varieties can be found in all the three studied classes. The best Hungarian climbing roses at blooming intensity were `Futótűz', `Rozalia', ‘Sarolt and 'Szent Erzsébet emléke'; best floribundas were ‘Báthory István emléke', 'Munkács', 'Szent Margit emléke; and the best Hungarian polyanthas were `Csinszka', `Domokos PáI Péter emléke'. Some really good flowering Western-European rose varieties have also been found, the best ones were 'Clg. Gertrude Westphal' climbing, 'La Sevillana' floribunda and 'Beauty of New South Wells', 'Happy' polyanthus. 'La Sevillana' and 'Picasso' were in strong bloom for the longest time.

    In Hungary, the floribunda and polyantha classes had good flowering intensity to the almost the same extent, floribundas had stronger, and polyanthas had longer flowering waves, but the ever-blooming ability of the climbing roses was moderate in the dry midsummer.

  • Scheduling of irrigation in snap bean (Phaseolus vulgaris var. nanus) using canopy temperature
    89-94.
    Views:
    133

    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.

  • The quality and storage efficiency of some apple varieties as a function of picking date, area of production and duration of storage
    99-103.
    Views:
    148

    Numerous apple varieties have been tested parallel with traditional Jonathan varieties during four years, 1990-1994 on three different geographical areas of Hungary. The picking time took place at three different times in a year: ten days before the probably optimal picking time, at close-to-optimal picking time, and ten days after the optimal picking time. The effect of storage on quality of fruits have been tested in February, March, and April under circumstances of a semi-industrial storage experiment.

    The results of experience can contribute to answer numerous current, from point of view of practice important topics:

    • The stochastic relations between various fruit quality parameters at different varieties
    • The change of fruit — quality during storage
    • The effect of different picking date on storage losses
    • The possibilities of storage — loss predicting by the utilization of multiple regression analysis.

    The most important results of experiences are as follows :

    1. The starch — degradation test and Streiff — index are well applicable for practical purposes to determine the optimal harvest-date.
    2. On base of analysis of various losses and physiological diseases the high importance of mass loss is obvious. In the variety Jonnee the earlier picking date considerably increased the mass loss. The effect of variety on mass loss is rather limited. In the Jonathan varieties the Jonathan spot was a rather important physiological disease. The late picking time increased the frequency of Jonathan - spot. At optimal date of harvest at Jonnee the frequency of Jonathan -spot was lower, than at Jonathan M 41. In the Jonathan M41 and Jonnee the importance of scald was rather limited, but in the Wellspur Delicious and Smoothee this disease occurred relatively frequently. In the Smoothee the earlier picking time considerably increased the probability of scald.
    3. The multiple regression analysis yielded reliable results, fit for prediction of storage losses and diseases on the base of chemical and physical properties, determined at the time of picking.

     

  • Leaf number and plant height of three Canna x generalis cultivars
    22-24.
    Views:
    249

    The aim of this three-year study was to evaluate the effect of three treatments (thiophanate methyl, charcoal dust, and control) on leaf number and plant height on three Canna x generalis cultivars (City of Portland, Richard Wallace and Robert Kemp). Results showed that the 3-year means of leaf number ranged from 13.9 to 23.1 for the three cultivars. The largest leaf numbers were for cultivar Robert Camp (23.1 in 2010) and the lowest for cultivar City of Portland (13.9 in 2011). Thiophanate methyl treatment produced the highest number of leaves and the values were significantly different at P< 0.05 from the control for all years and for all cultivars. Numbers of leaves in charcoal dust treatments were larger than the control treatments but it was not significantly different. Results on plant height ranged from 69.2 to 160.5 cm for the three cultivars. The largest plant height was for cultivar Robert Kemp (160.5 cm in 2011) and the lowest for cultivar City of Portland (69.2 cm in 2011). Thiophanate methyl treatment produced the highest plant height and the values were significantly different at P< 0.05 from the control for all years and for all cultivars. Plant heights in charcoal dust treatments were larger than the control treatments but it was not significantly different.

  • Effect of Erwinia amylovora infection on peroxidase enzyme activity in resistant apple cultivars
    37-39.
    Views:
    155

    Two apple cultivars that display enhanced resistance to fire blight (causal agent: Erwinia amylovora) were selected. The aim of the present study was to characterize the peroxidase (POD) enzyme activity of `Szemes alma' (a historical cultivar) and MR-03, (a Hungarian multiresistant hybrid of 'Prima') and compare them to susceptible 'Jonathan M 40' and resistant 'Remo' controls. Peroxides enzyme activity during E. amylovora infections was investigated in artificially infected apple shoots. Increases in enzyme activities were observed in a `Jonathan M40' and in 'Remo', MR-03, `Szemes alma' cultivars. There was a consistent relationship between total enzyme activity and fire blight disease severity. High activity of the peroxidase was positively correlated with the degree of resistance to fire blight. A general hypothesis that POD activity is related to fire blight susceptibility/resistance is supported by our results.

  • Results in the determination of some Hosta varieties by the method of isoelectric focusing
    90-92.
    Views:
    121

    Mass propagation of 5 newly introduced Hosta varieties was carried out by the method of micropropagation. Our aim was to determine exact variety specificity after the micropropagation period in the pattern of peroxidase isoenzymes by isoelectric focusing in pH 3-9 range and to determine that phenological phase of mother plant in which the isoenzyme pattern of mother plant can safely be comparable to the isoenzyme pattern of micropropagated descendants. The isoenzyme patterns of descendants were similar to the mother plants of the same hybrid lines. The older leaves seemed to be not so suitable for examination than newly developed ones despite of the higher activity of peroxidase enzymes. There were big differences in isoenzyme patterns of leaves in different phenological phases. With this quick and easy method Hosta varieties could be selected already in the very early stage of micropropagation.

     

  • Ecological drought resistance and adaptability of apple varieties
    113-122.
    Views:
    397

    For adequate yields in apple plantations, during the long growing period of the fruit primordia, one of the decisive factors is water supply. Indicators of stress are valuable signs for the diagnosis of drought and necessity of watering, i.e. planning the irrigation of plantations. The aim of the present study was to find reliable signs of water stress on apple trees and at the same time conclude on the drought tolerance of different varieties. The plantation of apple varieties grafted on various stocks and cultivated according to different systems (irrigated, non irrigated, integrate and biological) has been examined continuously by leaf analysis. Along the period of growing fruits, measurements were made in the field, then the leaf samples were analysed in the laboratory for composition of pigments, carbohydrates and antioxidants, as well as the histology of the tissues checked. Without irrigation, the mean leaf mass and the relative chlorophyll content (SPAD) of the variety Idared on M4 stocks increases beyond the values of 50 SPAD, whereas on M26 stock and integrated system, it declines. In the collection of varieties, grown according to the „integrated” system, during the development of fruits, ‘Gála’ and ‘Remo’ varieties have been affiliated to the “less susceptible” group regarding drought tolerance because of the leaf morphology, structure and content of SPAD and antioxidants. However, ‘Idared’ and ‘Jonagold’ belong to the “susceptible” group. To the same group are ranged the ‘Akane, Red Rome vanWell, Pink Lady’ varieties. Those varieties reacted to a short period of drought by increased production (content) of carbohydrates. Regarding changes of carbohydrate content ‘Greensleeves’ and ‘Ozark Gold’ varieties belong to the moderately water dependent (requiring) group. In the field, SPAD-tests facilitated the measurement of nutrient-uptake and incorporation, which is proved by the tight correlation between the data of SPAD and the increment of leaf weight (r=0.76–r=0.88), however, this depends on the variety too. SPAD is an indicator of water supply and is related with the density of stomata, cannot used for the selection of water-exigent varieties but for (drought) tolerant ones. In integrated culture, the (drought) susceptible varieties display (water-soluble) hydrophilic and lipophilic antioxidants (ACWand ACL resp.) the quantity of which may have some role in drought tolerance.

  • Fruit drop: The role of inner agents and environmental factors in the drop of flowers and fruits
    13-23.
    Views:
    515

    The basic conditions of fruit set (synchronic bloom, transfer of pollen, etc.) still do decide definitely the fate of the flower (Cano-Medrano & Darnell, 1998) in spite of the best weather conditions (Stösser, 2002). Beyond a set quantity of fruits, the tree is unable to bring up larger load. A system of autoregulation works in the background and causes the drop of a fraction of fruits in spite of the accomplished fertilisation and the equality of physiological precedents (Soltész, 1997). There are also basically genetic agents in action. The further development of fruits maintained on the tree depends mainly on the growing conditions (e.g. water, supply of nutrients, weather adversities, pruning, fruit thinning, biotic damages, etc.), which may cause on their own turn fruit drop especially at the time of approaching maturity.

  • Shoot induction and plant regeneration from cotyledon segments of the muskmelon variety "hógolyó"
    61-64.
    Views:
    144

    Cotyledonary segments of the casaba type muskmelon variety "Hógolyó" were used to induce organogenesis. Fifty different hormone combinations were applied to enhance the induction of shoot formation on the edge of the segments. The phases of organogenesis were followed with light- and scanning electron microscope. Shoot induction was achieved with high frequency. The shoots were transferred to hormone free media for root induction. The rooted plantlets were planted out to soil.

    NAA was feasible and the method can be applied in transformation experiments.