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Blumeriella jaapii (Rehm) v. (Arx) infection of some sweet cherry cultivars in two years with different precipitation conditions
37-39.Views:256We examined Blumeriella jaapii (Rehm) v. (Arx) infection on 21 sweet cherry cultivars in the cultivar-collection of the Experimental Station Pallag of the University of Debrecen, in 2004 and 2005. Considerable differences were detected in the infection degree of the different cultivars. In 2005, due to the more humid weather, the average infection highly exceeded data of the previous year. No symptomless cultivars were detected in either year. The least sensitive ones were Linda and the cultivar 11/106. The most sensitive cultivars were Early Müncheberg, Biggareau burlat and Round Solymári. Infection degrees of Alex, Rita and Vega were different from those of other cultivars on the basis of the two experimental years.
It is important to consider both the specific weather conditions of the year and cultivar resistance at planning the plant protection system. It is recommended for each cultivar to perform a fungicide-spaying after the harvest.
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Effects of different cytokinins on the shoot regeneration from apple leaves of 'Royal Gala' and 'M.26'
69-75.Views:386The effects of different types of cytokinins on the shoot regeneration from leaf explants of apple scion 'Royal Gala' and apple rootstock 'M.26' were evaluated. Regeneration media contained either thidiazuron, or 6-benzylaminopurine, or meta-topolin, or zeatin, or kinetin, or their N9-ribosides, respectively, in the concentration range 0.5 to 8.0 mg 1-1. Effects of 'these cytokinins were evaluated on the percentage of regeneration (R%) and that of vitrification (V%) and on the number of regenerated shoots per explant (SN). Organogenetic index (0I) calculated from these data was used for the evaluation of efficacy of cytokinins. The course of shoot organogenesis also was followed using stereomicroscope. Types and concentrations of cytokinins applied in the regeneration media influenced each parameter significantly and the regeneration answer was strongly genotype-dependent. The best regeneration (SN: 11.08, 01: 7.5) was achieved in `Royal Gala' by using TDZ in concentration of 0.5 mg 1-1 (2.271,1M). There was a clear relationship between the effect on the regeneration efficacy and the chemical structure of cytokinins considering classical cytokinins, namely N9-ribosides applied in less concentration than nonribosides have the same or best regeneration effects except for 6-benzylaminopurine riboside. However, similar relationship could not be detected in the case of 'M.26'. SN was the highest (3.22) using 6.5 mg 1-1 (18.2011M) 6-benzylaminopurine riboside or 8.0 mg 1-1 (21.44 µM) meta-topolin riboside (3.18). SN was not significantly lower (3.12) by using 2.0 mg 1-1 (9.08 1M) TDZ, however, OI was about half as big (0.63 compared to 1.29 or 1.74 with 6-benzylaminopurine riboside or meta-topolin riboside, respectively). 'Royal Gala' had higher organogenetic ability, than `M.26': 3.5-fold higher shoot number per explant and more than 4-fold higher organogenetic index was reached with this cultivar than with 'M.26'. Moreover, the similar developmental stage of shoots could be observed 3-5 days earlier than in 'M.26' and if explants of 'Royal Gala' were further cultured with 3 weeks, SN increased from 11.08 to 24.42 on TDZ-containing regeneration medium, which might suggest higher organogenetic ability, too.
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Effect of hydroponic and peat-free media in transplant production of Rudbeckia hirta varieties under different photoperiodic lighting and their photosynthetic parameters
110-117Views:555The purpose of this research was to determine the effects of varieties, different light conditions (short day, long day, natural short day with light pollution), and different growing media (perlite, peat-free, peat-based, aeroponics system) on Rudbeckia hirta plant production under controlled conditions (greenhouse). The morphological effects of each treatment (photoperiodic lightings and media) on different Rudbeckia varieties determined at 11 weeks-old ’Napfény’, ’Toto Gold’, ’Autumn Colors’, ’Prairie Sun’ and 16 weeks-old ’Napfény’. Plantlets received 12 hours daylight did not initiate flowers, remained stage of the leaf rosette in case of all varieties. The 14 hours light treatment in the aeroponics system and the same treatment in perlite and control (natural short day with 14 hours light pollution) plantlets had developed inflorescences or flower buds. The inflorescence axis of ‘Napfény’ was appeared at 13 weeks under long-day conditions, with 1.7 (perlite) - 2.7 (aeroponics) flower buds in 16 weeks. ’Toto Gold’, ’Autumn Colors’, ’Prairie Sun’ varieties developed inflorescences at 8 weeks, 14 hours aeroponics system resulted in the most of flower buds (’Toto Gold’: 6.5, ’Autumn Colors’: 3.25,’Prairie Sun’: 4.8 flower buds) at 11 weeks. Long daylight manipulation could be minimized crop times and achieved flowering potted plants at 11 weeks. The peat-based and peat-free media effect was observed on ‘Autumn Colors’. The number of leaves of peat-free ‘Autumn Colors’ transplants (16.8-20.3) was significantly higher than peat-based media (13.5-15.5). Other morphological parameters were not affected by the media treatments.
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Effect of a nanotechnology-based foliar fertilizer on the yield and fruit quality in an apple orchard
29-32.Views:1042Nutrient management is a determining element of the technology in fruit production. Significance of foliar fertilization has been increased continuously over the last years, as it can improve directly the vegetative and generative performance of the trees. In this study we aimed to evaluate the effect of a nanotechnology-based foliar fertilizer (Bistep) with 1, 3, and 5 l/ha dosages on the yield and fruit quality parameters in an apple orchard during 2016 and 2018. According to our results, crop load increased with 29% in the third year of the experiment with the application of 5 l/ha Bistep treatment compared to the control treatments. Fruit weight was also improved in each year, as values of fruit weight in all treatments were higher than the control one (3.0-13.0% growth). Fruit surface color increased with 2-18% due to the foliar fertilizer. During the three years, leaf length was 9.5-9.9 mm on the control trees, as 9.8-10.4 mm was measured on the fertilized ones. In conclusion, yield and fruit quality can be improved in apple orchard using a nanotechnology-based foliar fertilizer.
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The evaluation of grape vine decline pathogens in the experimental field of the Georgikon Faculty of Agriculture in Cserszegtomaj
19-22.Views:278Vine decline causes important economic loss in viticulture, especially in longer view. Several causal pathogen were described lately, however little is known about the etiology or epidemiology of these pathogens on grapevine rootstock. It is well known that these diseases affect grafted and rooted grapevines and are not specific to any scion-rootstock combinations. Our aim was to determine what pathogens are presents in the experimental field, especially causal agents of the rootstock decline. Different grapevine rootstocks and scion varieties were tested in our trial. Isolations were made from the wood tissue and pathogenity tests were done with isolated Cylindrocarpon destructans. The possibility of infection during the propagation process was studied as well. Most commonly Cylindrocarpon sp. and Phomopsis sp. species were identified from the examined varieties. Cylindrocarpon destructans was able to spread to apical (shoot) and basal (root) direction from the point of infection with uneven speed. Callus development is not inhibited by the fungi causing the leaf symptom of the vine decline. Shoot development is reduced if unhealthy parts are grafted to each other.
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Changes of the characteristics of Satureja hortensis L. herb during flowering period
56-60.Views:230In this study the changes of the characteristics of Satureja hortensis herb were investigated during flowering period, in case of savories of 4 different origins. The change of drying ratio, leaf/stem ratio, essential oil content, the ratio of several essential oil components (carvacrol, y-terpinene, p-cymol, a-pinene, p-pinene and fi-caryophyllene) were studied from bud formation till seed ripening.
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Optimization of fertilizer use efficiency, soil quality and oil palm (Elaeis guineensis Jacq.) growth with biochar under drip irrigation conditions irrigation conditions
31-36.Views:332Biochar (BC) is an eco-friendly product characterized with high content of carbon and usually obtained by heating biomass without oxygen. Utilizing BC as organic material to amend the problematic soils and improve plant growth and yield has been proved previously. This study investigated the effect of vetiver grass biochar (VGB) on fertilizer use efficiency, soil quality, and oil palm growth performance. A net house experiment was conducted at the Farm Unit, UiTM Sarawak Branch, between August 2022 and March 2023. A factorial randomized complete block design (RCBD) with five treatments and four replications was devised. Treatments applied were: T0) absolute control; T1) 100% NPK fertilizer; T2) 100% vetiver grass biochar; T3) 50% vetiver grass biochar + 50% NPK fertilizer; and T4) 25% vetiver grass biochar + 75% NPK fertilizer. The BC application significantly improved the fertilizer use efficiency through reducing the rate of fertilizer applied. It also significantly enhanced most soil-measured chemical properties and soil nutrients. The growth performance of oil palm plant was significantly enhanced by BC application in terms of plant height, hump diameter, leaf number, chlorophyll content, and plant biomass. The BC application demonstrated its usefulness in managing soil and cultivating oil palm plant sustainably by reducing the rate of fertilizer applied and improve the fertilizer use efficiency. Based on the output, we suggest that treatment T3 (50% vetiver grass biochar + 50% NPK) can be used to improve the growth performance of oil palm.
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Integration of terrestrial laser scanning and spectral canopy scanner in horticulture applications
15-18.Views:684One of the most difficult challenge in the everyday practice to describe the canopy growing of fruit trees in an orchard. The photosynthetic activity is the basic of the primer production of plants. The measurement of leaf area and determination of the photosynthetic activity could be occurred with some elaborated methods between experimental conditions. In this article we present such an integrated methodology, which is ideal to determine the geometric and spectral characteristic of fruit trees between field conditions.We have carried out laser scanning technology to investigate the geometric-topological characteristics and parallel the active infra-red sensor to collect spectral data about an apple orchard. The surveys were worked out in an intensive apple orchard with drip irrigation system, protected by hail net in Study and Regional Research Farm of the University of Debrecen near Pallag. This study shows the filtering and interpretation methods of created data. The produced high accuracy data can be directly used in the precision horticulture. It could serve as a guiding data to implementation a future “virtual horticulture”. Higher spatial and temporal resolution could help for a better recognition of water balance of orchards.
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Comparative investigation on Hypericum perforatum L. populations of different origin
56-60.Views:375Widespread application for herbal medicines based on Hyperici herba has been experienced in the last few years, especially in the treatment of depression syndrome. As the wild origins could not satisfy the market demands neither in quantitative nor in qualitative respect, the necessity of the development of intensive growing methods has been raised. In the course of our investigations we intended to clear up the morphological and chemical variability among and within populations of different origin in order to start a new breeding program. According to our data, growth dynamics of populations could be characterised by a logistic curve. According to the time of flowering the populations formed early, middle and late groups. Morphological diversity among populations was measurable in differences of flower length, plant height, different leaf types and plant habit, according to which characteristics groups were distinguished. Generally, the accessions were the most homogenous in plant height (CV: 7-15%), followed by inflorescence-lengths (CV: 11-36%) and the least uniform characteristics proved to be the number of flowering shoots (CV: 14-59%). The greatest morphological heterogeneity was experienced in the accessions of wild origin as it has been expected. In the second vegetation period generally a much better homogeneity was obtained, than in the first year. The most outstanding accessions produced 1.2 t of dry flowers and 4 t of dry flowering shoots, calculating to one hectare area. The individual yields varied on a large scale in each population (CV: 18-70%).
The content of hypericin varied between 1,85 and 9,9 mg/g in 1996, and between 0,18 and 2,70 mg/g in 1997, showing high individual divergences. Flavonoid values -including first of all hyperosid, rutin and quercitrin - reached 17-39 mg/g in the first and 15-20 mg/g in the second year, respectively. Individual and seasonal variation was less than in hypericin. A joint high level of these two compound groups seems to have low frequencies.
The superior population were selected for further breeding.
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Estimating of water consumption of cherry trees
15-17.Views:339Despite of its importance there is no exact information on water use of new scion/rootstock composite trees, which would be needed to optimized irrigation. Our research purpose is to define exact water-demand of different rootstock/scion composite trees, calculating seasonal weather changes and by using the results decrease irrigation costs. The investigations are carried out in Soroksár, at the Experimental Farm of Corvinus University of Budapest in May 2008. From among the investigated trees two are budded onto Prunus mahuleb `Érdi V' seedlings, two on "Korponay' seedlings. The sapflow measurements are carried out using Dynamax Flow 32 equipment with Dynagage trunk sensors. The first daily maximum of sapflow was around 10:00 a.m. (2.5 kghour I), the second maximum was always between 14:00-15:00 p.m. (2 kgday- I). Comparing to the very intensive morning water uptake by 20:00 p.m. the water flow slowly reached the minimal level. Significant differences can be seen on rootstocks: trees on `Korponay' rootstock always showed more intensive sapflow and a higher morning peak than trees on `Árdi V'. But later during the day they have the same run.Based on our results the water quantity transpired only by the trees reached in May 86-104 mm, while the precipitation was only 42.4 mm. This means a 40-60 mm deficit in the orchard, which should have been supplied by irrigation despite of the satisfying horticultural performance of the orchard. In the first half of the month beside the steady vapor pressure deficit the shoot and leaf surface growth could cause the increased sapflow.
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Effects of aromatic cytokinins on structural characteristics of leaves and their post- effects on subsequent shoot regeneration from in vitro apple leaves of 'Royal Gala'
41-46.Views:345The effects of different aromatic cytokinins applied in different concentrations and combinations were investigated on the histology of in vitro apple leaves and their post-effects on subsequent shoot regeneration from these leaves were studied. Great differences in the anatomical structure of leaves could be detected originating from media containing different types and concentrations of aromatic cytokinins. The number of regenerated shoots per explant and the organogenetic index were used for the evaluation of the post-effect of aromatic cytokinins on shoot regeneration. The histological structure of leaves used for regeneration and their regeneration response showed a good correlation. When the pre-treatment caused a juvenile-like or less-differentiated structure, the number of regenerated shoots per explant increased and often vitrification also decreased and consequently the organogenetic index also increased. A strong interaction between cytokinin-content (type and concentration) of the pre-treatment medium and that of the regeneration medium could also be detected.
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Anatomical study of the bud union in „Chip" and „T" budded 'Jonagold' apple trees on MM 106 rootstock
27-29.Views:599The traditional methods for vegetative propagation of apple and its varieties are the T-budding, and the winter grafting, but this latter way is a difficult and expensive procedure.
In our experiment carried out in the Fruit Tree Nursery Soroksár, the healing process of chip- and T-budded apple trees 'Jonagold' on MM 106 rootstock was studied.
The budding (T- and Chip-) was made in the first week of August, samples for microscope examination were taken monthly after this time until leaf fall.
The investigated part of plants was made soft with 48 % HF (hydrogenfluoride), then cross and longitudinal section were made and examined by microscope.
Based on analysis of microscope pictures in case of Chip-budding, it was established, that development had started quickly after budding on the rootstock and scion too. But the callus originated almost entirely from the rootstock tissue as new parenchyma cells fills the gap between the two components of graft (scion and stock), becoming interlocked and allowing for some passage of water and nutrients between the stock and the scion. This quantity of callus in case of T budding was under the scion buds larger, than the Chip-budded unions, where the thickness of callus mass is uniformly thick round the chip. The large mass of callus pushes the scion bud outwards from the shoot axis, which later results in a larger shoot-curvature above the bud union.
Following this process on the Chip-budding it can be observed also, that a continuity of the cambium is established between bud and rootstock. Then the newly formed cambium started typical cambial activity, forming new xylem and phloem.
Later the callus begins to lignify, and it is completed within about 3 months after budding.
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Preliminary study on micro area based spatial distribution of powdery mildew in an organic apple orchard
35-37.Views:362In this study, the objective was to report a preliminary study on micro area based spatial distribution of powdery mildew in an organic apple orchard. Results showed that number of symptomatic plant part ranged between 11 and 20 on shoot and between 9 and 24 on fruit. Number of asymptomatic plant part ranged between 85 and 109 on shoot and between 133 and 206 on fruit. Disease incidence ranged between 13.8 and 17.6% on shoot and between 9.1 and 11.3% on fruit. Disease aggregation index ranged between 0.098 and 0.228 on shoot and between 0.043 and 0.108 on fruit. One of the four trees showed significant within canopy aggregation of disease for shoot powdery mildew symptoms in both years. For leaf powdery mildew, all tree exhibited random patterns in both years.
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In vitro multiplication and hardening of grapevine plants in aeriated media
15-18.Views:321In vitro cultures have widely been used in horticulture for rapid multiplication of new varieties and clones as well as to produce pathogen-free stock material. To improve efficient hardening and transfer in vitro grown grapevine plants were multiplied by cutting them into single-node internodes with the whole leaf. Microcuttings including the shoot tips were rooted in granulated perlite moisted with tapwater under sterile conditions. After 2-3 weeks the rooted microcuttings were supplied by nutrients and hardened by gradual opening and finally by complete removal of the lids of jars or plastic boxes used for growth. Using this method microcuttings of Vitis vinifera cvs. „Chardonnay", „Cabernet franc", „Riesling" and „Sauvignon blanc" and the rootstock varieties Vitis riparia x Vitis cinerea cv. „Barrier" and Vitis berlandieri x Vitis rupestris cv. „Richter 110" formed new roots and shoots and 100% of the tested plants survived the acclimatization procedure. Similar results were obtained when perlite was replaced with rockwool-, or pit-pot blocks. This method may highly increase the efficiency of producing pathogen-free propagating material and new transgenic lines.
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Results of cherry rootstock evaluations in Hungary
11-14.Views:358The paper gives a review on the results of the latest rootstock evaluation projects in Hungary. Several cherry rootstock evaluation projects were carried out in Hungary during the last two decades. The evaluated rootstocks are partly mahalebs selected in Hungary, but more or less all the most important new rootstocks from different countries are involved. The aim of these evaluation projects was to find appropriate rootstocks in a wide range of vigour for our climate and soil conditions. The conclusion of the last 20 years of research in Hungary proved just the opposite of believes, that high density orchard can only be planted with dwarfing rootstocks. Before choosing the right rootstock the most important is to consider adaptability, precocity and productivity. Dwarfing and semi-dwarfing rootstocks showed proper results only with irrigation or very good site conditions. These rootstocks are very precocious, but branches form easily blindwood. This must be corrected by severe pruning in the first years. The relatively small leaf surface area can also be disadvantageous, but it can be controlled by pruning, fruit-thinning, irrigation and fertilization. After studying different rootstocks semi-vigorous rootstocks seem to be the most adequate for different site conditions in Hungary. Fast initial growing and competent precocity are their favourable characters. From the vigorous group of clonal mahalebs or seedlings are highly recommended first of all for poor site condition (sandy, lime soils with high pH). They turn to bearing early and easy to find them in the Hungarian nurseries. But on vigorous rootstocks trees might need stronger summer pruning.
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Bud-, flower- and fruit-density in stone fruits
59-69.Views:752In 164 varieties of five stone fruit species, counts of flower buds, flowers and fruits set have been performed, regularly, between 1982 and 2002. The critical number and sample size has been determined for the purpose to estimate the yielding potential of peach plantations. For a rapid test, 10 shoots per variety are recommended. In sour cherry and peach varieties, the number and ratio of leaf and flower buds has been assessed on bearing shoots of different length.
The typical flower bud density of 129 peach varieties varies, as a rule, between 0.13 and 1.10 bud/cm. Three groups of flower-bud-densities could be distinguished: low (0-0.40 bud/cm), intermediate (0.41-0.60 bud/cm), high (more than 0.60 bud/cm). About 62% of varieties belong to the intermediate group. Negative correlation has been found between flower density and relative fruit set, whereas positive correlation between flower density and fruit yield.
The results are utilised in the description and choice of varieties, moreover, in choosing of optimal pruning policies. Varieties of high flower bud densities are recommended to be preferred for growing sites with frequent late frosts. Abundantly yielding varieties of low vegetative vigour are to be pruned more severely than those characterised by low yields, vigorous growth and low flower density. Sour cherry varieties, which are inclined to grow "whips" ought to be stimulated to grow longer shoots (40-50 cm per year), than varieties woid of that tendency (30-40 cm).
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Left, right, up and downstage: leaves and lateral roots histological trait prospection for drought tolerance in commercial Coffea arabica cultivars
44-65.Views:568The climate change and water deficit challenges plant producers all over the world, and have consequences to coffee production and quality. In this research we have approached anatomical traits from vegetative organs of 13 Coffea arabica genotypes, selected based on their contrasting behavior to water deficit. Leaf blade, petiole and primary root cross sections were evaluated, and the epidermal, fundamental, and vascular tissues descriptive anatomy, histometric and histochemistry examined. Despite all plants were in the same environment (CEPC/EPAMIG, Patrocínio, MG, Brazil), there were differences among the genotypes and groups of more tolerant and more susceptible accesses. Petiole cross section, vascular tissue and phloem and cambium; and percentage of stele, pericycle and phloem and cambium in primary roots exhibited differences among the contrasting genotypes, highlighting an inborn association of vascular tissue and other features with water deficit resistance. This association was observed in the mild to medium correlations among vascular tissue, epidermis, phloem and cambium in roots and petioles. Possible relation of qualitative traits such as the lignification of root epidermis, lipidic substances in outer cortical cell layers, and area/number of cell layers in the cortex are approached as possible traits in the seek for water deficit tolerance in C. arabica.
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Effect of three organic fertilizers treatments on sensory evaluations of baby spinach (Spinacia oleracea L.)
59-63.Views:484Sources of fertilizer are one of the major factors influencing baby spinach leaf texture, sweetness, bitterness and after-taste. However, the effects of fertilizer sources on baby spinach growth performance and consumer preferences are not known. A survey was carried out at the Seke Teachers’ College (SKC) community, Zimbabwe to determine the consumer preferences on the baby spinach grown on the organic fertilizer (cattle, poultry and goat manures) as well as on control inorganic fertilizers (7% N, 14% P, 7% K). The study used 32 females and 30 males as panellists for sensory evaluations. Organoleptic tests were performed for the baby spinach leaves using a panel of 62 testers. An interval line scale (16 cm long) was used to measure the liking for sweetness, colour, bitterness and after-taste. A 9-point hedonic scale was used to decide the overall preferences. Organoleptic tests showed significant differences (P<0.05) in appearance and taste between the inorganic and organic fertilizers used. The baby spinach leaves grown on organic fertilizers was preferred more compared to that grown on inorganic fertilizer (control). Therefore, it is recommended to use organic fertilizers in baby spinach production in order to satisfy consumer preferences.
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Nutritional aspects of producing fruits organically
69-74.Views:613Recent interest to avoid use of agrochemicals in fruit growing to safeguard environmental and human health has stimulated interest in organic fruit production (OFP) all over the world. Organic production requires a holistic approach to agricultural ecosystem management. Because of the perennial nature of orchards, this is not a great departure from conventional orchard management, except that corrective techniques are limited primarily to naturally derived materials. Organic mineral nutrition management hinges on two principles: 1) practices that lead to the build up and maintenance of soil that is biologically active and high in organic matter; 2) supplementing the mineral nutrients provided by the soil with fertilizers from approved sources. Organic orchards should be sited on land with superior soils and preplant soil preparation to increase organic matter and correct any sub-optimal soil characteristics. For successful organic fruit growing the following statement should be considered:Weed management is critical to reduce competition for nutrients and water. Soil and leaf analysis provide the basis for correcting mineral nutrient deficiencies or imbalances in organic production. It may be necessary to use a number of strategies to supply mineral nutrients over the life of the orchard. The slower, natural methods applied require a management approach that is simultaneously patient and dynamic.
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The impact of location, row direction, plant density and rootstock on the sunburn damage of apple cultivars
19-30.Views:929The effect of row direction (N-S, E-W), plant density (conventional and intensive) and rootstock (M9, MM106 and crab apple) on the sensitivity of 41 apple cultivars to sunburn injury was studied at 6 locations (Derecske, Kálmánáaza, Nagykutas, Nagylapos, Siófok, Tornyospálca).
During the observations the cultivars had rootstock-specific properties in respect of sunburn-susceptibility. Accordingly, the injury was decreased in the order: M9, MM106 and seedling rootstocks. The differences in sensitivity depend on the canopy of trees, caused finally by the growing vigour of rootstocks. Accordingly, the highest value of sunburn injury was observed on M9 rootstock, because this rootstock has a dwarfing effect upon the scion cultivars. Thus, vegetative area of these trees grow very slowly and the foliage is not enough compact to protect the fruit from solar radiation. The size and density of the foliage increased in the order: M9, MM 106 and crab apple seedling as rootstock. Moreover, relationships were demonstrated between the diameter of upper part of the crown, the leaf area, the number of fruits per tree and the injury of sunburn.
Authors categorized the cultivars in respect of values of sunburn incidence: 1. „Not sensitive", II. „Moderately sensitive" and HI. „Strongly sensitive" categories were constituted. Generally, Topaz and Gala cultivars showed low damage (or were free from symptoms), in contrast to this, Golden mutants suffered relatively much. The most sensitive cultivar was Jonica on all the three rootstocks. We searched for relationship between the fruit quality parameters and the frequency of sunburn. Significant correlation was found in the cases of fruit size and the extent of cover-colour. The latter is interpreted with the fact that the best coloured fruits are found on the periphery of crown as a consequence of more intense irradiation.
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In vitro rooting and anatomical study of leaves and roots of in vitro and ex vitro plants of Prunus x davidopersica 'Piroska'
42-46.Views:346The process of in vitro rooting and the anatomical characters of in vitro and ex vitro leaves and roots of Prunus x davidopersica 'Piroska' were studied. Best rooting percentage (50%) and highest root number (5.0) was achieved in spring on a medium containing 0.1 mg/I NAA + 30 g/1 glucose. At the end of rooting the parenchyma of the in vitro leaves was more loose and spongy, than during the proliferation period. In the first newly developed leaf of an acclimatised plant, the parenchyma was much more developed, contained less row of cells and less air space too, compared to the leaves developed in the field. The in vitro developed root had a broad cortex and narrow vascular cylinder with less developed xylem elements, but at the end of the acclimatisation the vascular system became dominant in the root.
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Chemical communication with volatile semiochemicals in Phyllotreta species (Coleoptera, Chrysomelidae): a minireview
93-100.Views:436Phyllotreta species (Coleoptera, Chrysomelidae, Halticinae) rank among the most important horticultural pests in the Northern Hemisphere. Leaf damage caused by flea beetles upsets the water balance, blocks plant growth and sometimes causes a high level of mortality of seedlings. Several species are known to act as vectors of numerous pathogens as well. Chemical communication plays an important role in the host finding, feeding and oviposition behaviour of flea beetles. In the first phase volatile mustard oils (isothiocyanates and thiocyanates) are released from the host plants through the decomposition of non-volatile glucosinolates (chemicals specific to Cruciferae) by myrosinase, and beetles are attracted to the source of release from a distance. Among the isothiocyanates, allyl isothiocyanate is the longest known and widespread compound utilized in the host-plant location of Phyllotreta species, but some species may have a stronger preference to other isothiocyanates or thiocyanates. The attractive effect of the plant volatiles is enhanced by the emission of a male-produced aggregation pheromone. The presence of such a pheromone was first demonstrated in Phyllotreta cruciferae Goeze. In this species R5R,5aS)-1,1,5,8-tetramethy1-1,2,3,4,5,6,5a-heptahydrobenzo[1,2-a][7]annulene] was found to be the main pheromone component. Significant attraction by the pheromone was recorded only in the presence of ALLYL ITCN. The biological activity of the pheromone compound was connected to the plus (+) chirality. The same component seems to be occurring also in the pheromones of several other Phyllotreta spp. as well, suggesting a wider occurence in the genus. Once attracted by the joint effect of plant volatiles and aggregation pheromone, the presence of the non-volatile glucosinolates in the plant tissues is necessary for continuous feeding. Aggregations of flea beetles on suitable host plants, which result from the joint effects of plant-derived and pheromonal chemical cues detailed above may also be good rendez-vous occasions, increasing the probability of encounters with the opposite sex and mating in the vicinity of the optimal oviposition site. Due to the horticultural importance of Phyllotreta spp., deciphering details of their chemical communication has considerable significance in the development of new methods of integrated control.
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Morphological and phenological properties of sour cherry varieties grown in Hungary and their inter-incompatibility relations
114-117.Views:778Regular observations and experiments were performed during a 14 year period on 6 sour cherry varieties. The morphological traits of leaves and fruits were compared, and the phenology of blooming as well as of ripening dates served to start an estimation of the possibilities of mutual pollination and the planning of harvest operations. Experiments involved obligate autogamy, artificially controlled allogamy and open pollination in order to reveal self-fertility, self-sterility or inter-incompatibility relations.
The varietal characters represent, each, different values in the distinction of the items, because of their intra-varietal variability. From that point of view, the most reliable are the data of blooming and ripening time, fruit size and the fertility relations.
Inter-incompatibility was observed between the group of self-fertile, "Pándy type" varieties (`Újfehértói fürtös’, ‘Debreceni bőtermő’, ‘Kántorjánosi’) on one side and the selection of Pándy 7', a self-sterile variety on the other side. Unilateral incompatibility has been detected within the former group of new, self-fertile varieties, the combinations: (`Újfehértói fürtös’ x ‘Debreceni bőtermő’ as well as `Újfehértói fürtös’ x Kántorjánosi’.
Our results prove the close kinship between those three new varieties and the original Pándy variety on the base of being highly similar in their morphology and also of the fact of their inter-incompatibility, though unilateral.
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Field trials with non-bactericide products to control fire blight in apple orchards
55-60.Views:219Recently, novel strategies and chemical agents for prophylactic protection against the bacterial (Erwinia amylovora) disease fire blight are being sought. Resistance-inducing compounds, such as prohexadione-Ca represent promising alternatives. Prohexadione-Ca is the active ingredient of the bioregulator Regalis, currently being introduced in several European countries and overseas. Another product used in this study was Biomit Plussz, a leaf fertiliser providing harmonic supply of nutrient elements, the complete supply is assumed to improve the tolerance against diseases.
Treatments' effects of both of these products were compared to the effectiveness of treatments with antibiotics repeated twice, three or four times a season.
In the years of 2001 and 2002, the effectiveness of both Regalis and Biomit Plussz in reduction of incidence of shoot blight was similar, or proved to be superior to the check treatments consisting of repeated sprayings of antibiotics. Last year (2003) treatments of streptomycin resulted — although within the same magnitude — in a somewhat better control of shoot blight than sprayings with the other compounds.
As regards severity of blossom blight, inconsistent results were recorded concerning both Regalis and Biomit Plussz.
In general, prohexadione-Ca is less efficient for controlling flower infection by E. amylovora as compared to shoot infections, since successful prophylactic treatments are difficult to carry out early in the season. The highest effectiveness in fire blight management can, therefore, be achieved by using prohexadione-Ca (as preventive protection) in combination with streptomycin or other suitable antibiotics (as curative protection).
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Comparative study of effects of a complex fertilizer and a biostimulator on macroelement content of leaf and fruit quality on sweet cherry (Prunus avium)
91-94.Views:642In this study. we are partly focusing on consumer acceptance of fruit, like fruit cracking, weight and flavours, and maturation, fruit density and content of nutrients which are undelie consumer acceptance, and important equally to the growers and marketers. the results on the dynamics of N-uptake corresponded ti thephenological phases of cherry and independent on the applied treatments. Younger leaves contain more N than elder due to the effective N uptake of young leaves. Based on the measurements conducted in June, the P content of leaves was in low P supply category at the control and the Benefit treatment, while was in the lower range of optimal category at Damisol treatment. According to our measurements, the K of cherry leaves decreases continuosly until September, expcept the control at which it increased from the end of June to September. the fruit weight was increased significantly by applying Benefit PZ. the best results for fruit cracing observed at Benefit treatment too. The best result for fruit density was observed at Damisol treatment.
