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Effect of different starter and foliar fertiliser rates on some compositional parameters of sweet corn (Zea mays convar. saccharata Koern.)
41-44.Views:198In recent years consumers tend to pay ever greater attention to food ingredients looking for foods with favourable compositional characteristics. Researches nowadays aim to find out what role the different vegetable species play in protection of the human organism. Consumption of vegetables and fruits more times a day plays an important role in this process. The valuable chemical components in plants can eventually be influenced, besides, by environmental characteristics, also by the elements of the production technology applied. Our work aimed to find out what eventual changes occur in the composition parameters of sweet corn (Zea mays convar saccharata Koern.) receiving different NPK fertilizations and top dressed with foliar application of Zn and Mg, destined chiefly for fresh consumption, in response to the treatments mentioned above. The fertiliser rates were compared with the help of the variety Spirit (normal sweet, very early ripening).
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Assessment of soil characteristics in orchard
11-14.Views:192The research field was at Siófok, in Hungary, which is situated in the South East side of Lake Balaton. The physical characteristic of the soil is sandy loam and loam and the peach orchard is irrigated. The detailed goals were mapping and analyzing of physical properties of the soil in water management point of view, mapping the acidity and CaCO3content of soil for precision liming, measurement of humus the element content. Sites with different physical characteristics (from sandy loam to loamy clay) could be distinguished. The reason for this is that besides the possible increase of clayminerals, the increasing rate of colloidal humus content contributes to larger soil plasticity. Statistics also proved positive and strong correlation (r=0.822) between the soil plasticity and humus content. In the case of pH, only a small part of the orchard is has to be limed, since most of the orchard has neutral pH, which is advantageous for nuts and stone fruits. It has to be mentioned, that the CaCO3 supply is also appropriate for the stone fruits. Based on the results hyperspectral imagery can be a good solution for detecting calciferous soils, although these measurements are still need validation.
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Tree growth and inner characteristics of fruits in pear cultivars
29-32.Views:110Summary The aim of study was to investigate growth (crown growth and trunk diameter) and fruit characteristics [dry matter content (%), pectin (%), total acid (%) contents] of 10 pear cultivars ('Móri császár', 'Nyári Kálmán', 'Mogyoródi óriás', 'Fehérvári körte', 'Szegfa körte', 'Piroska', 'Mézes körte'). The crown development of the cv. 'Fehérvári körte' can be regarded as outstanding among the examined cultivars. The growth of the cv. 'Mogyoródi óriás' was low, this cultivar showed the poorest growth vigour. The width of the crown in several cultivars developed at a similar rate as the height of the crown. Outstanding values were shown by cvs. 'Fehervári körte' and 'Móri császár'. The development of trunk diameter was the highest for cvs. 'Piroska' and 'Hóka', and large growth of trunk diameter can be seen on cv. 'Fehervári körte'. Cvs. 'Mogyoródi óriás' and 'Mezes körte'showed weak growth. Outstanding dry matter content of fruits was measured on cvs. 'Fehervári körte' and 'Mézes körte'. The total acid content of fruits of cvs. 'Mézes körte' and 'Fehérvári körte'' was significantly different from the total acid content of cv. 'Mogyoródi óriás'. Pectin content was low in fruits of cvs. 'Mogyoródi óriás' and 'Fehérvári körte', while cv. 'Mézes körte' contained significantly more pectin. Vitamin C content we found was rather high in cvs. 'Mézes körte' and 'Fehérvári körte'.
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Cultivation systems in plum orchards
125-129.Views:250In this review, we give an overview of recent cultivation systems in commercial plum orchards. The aspects of selecting the shape of the crown and the spacing of trees are discussed first and then growth characteristics and the structure of the crow are described in detail. Finally, the wound healing and regeneration characteritics of plum trees are detailed which have an influence on the applied pruning technique.
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Preliminary results of renewal pruning an 18 years old sour cherry trees
41-42.Views:168Sour cherry is a light demanding fruit species. As most of the crop is developing from buds on one year old shoots and 2-yearold wood, the formation of bare wood can be seen apparently in a badly maintained canopy. The formation of „whip shoots” indicates the degree of bare wood. Unfortunately in many gardens and commercial orchards sour cherry trees resemble willow trees. Owners often decide to grub old orchards, although the useful cropping lifespan of the trees planted in a correct spacing can be 20-30 years on a move vigorous rootstock. Therefore renewal pruning can contribute to the full renewal of the orchard, but the length of its effect is depending on the growth characteristics and renewal capabilities of the cultivar. The growth characteristics of the cultivars are different. The regeneration capabilities of different aged wood are also different. These differences emphasize the need for cultivar specifi c pruning. Knowing the reactions to renewal pruning, we can ensure regular high crops with excellent quality by applying cultivar specifi c rotation pruning.
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Specialities of the vegetation start and level of primary fruit set affect fruit quality
17-22.Views:165Thinning is a h ighly crucial point of the apple production technology. According to results of numerous studies the earliest thinning is deemed to have the best amending effects. There can be considerable difference between trees of the same cul tivar and age in a plantation in respect to their flowering, in the numbers of fruits set and also in their canopy volume. Thus it can be crucial -just l ike in the case of pruning- to establish a fruit thinni ng su i ted for specif ic characteristics of actual trees. This experiment was established to examine how does primary fruit set (fruit load before thinning) and further on specific (fruit/TCS cm2) and absolute (fruit/tree) fruit-load of the trees affect quality attri butes at harvest. Our experiment was establ ished in a plantation on medium-tight loamy soil in north-east of Hungary. Harvest date was determined w ith the joint observation of the calendar date, starch-index, flesh firmness, background colour and fruit weight. Three fruit-load levels were established based on local experience and on data of several years, I Ot/ha lower and higher besides the advised optimum yield in the same orchard with slender-spindle shaped 'Gala must' cultivar standing on M9 rootstock in 1m x 3,8 m spacing. In the establishment of the 15, 25 and 35t/ha fruit-load levels on 20-20 apple trees total number of fruits set was counted at each tree. After this number of apples due to be removed was defined using an objective index on the basis of trunk cross sections (fruit/TCScm2) (Lafer, 1999). The following attributes were measured: weight (g), flesh firmness (lb/cm2) total soluble solid content (Brix %) and total titrate-able acid content (g/J).From the data on sugar and acid content quality index (Pomona value) was determined (Thialult, 1970). We could ascertain, that in an orchard, of the same aged but in concern to trunk cross sections somewhat different trees besides the specific index (apple/TCS cm2 the absolute fruit load (fruit/tree) can also be an important data, that has considerable effect on the internal quality. Secondly we could observe, that higher level of fruit load before thinning (primary fruit set) negatively affects quality index of the apples irrespective of the specific fruit load level (fruit/cm2 TCS) set later. Results underlines necessity of the earliest chemical thinn ing.
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Above-ground dendromass of sprouted black locust energy plantations: a case study
19-21.Views:239Black locust (Robinia pseudoacacia L.) can be considered as one of the most suitable tree species for establishing energy plantations due to its favourable growing characteristics such as vigorous growing potential in the juvenile phase, excellent coppicing ability, a relatively high resistance to pests. Based on national and international test results the mean annual increment of oven-dry weight of energy plantations regenerated by coppicing generally exceeds the first cycle plantations established by seedlings.
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Evaluation of the vegetative and generative performance of new apple cultivars in the Nyírség region
39-44.Views:221In this paper we examine apple varieties, which are planted expansively in the development apple orchards of the Western- European countries, but about its production characteristics we don’t have or just few practical experiences in Hungary. These varieties can be described with regular and high yields, aesthetic and alluring appearance in their origin places, what ensure profitable producing for the growers. Under the Hungarian climate which tends to be often extreme (hard cold winters, late spring frosts, summer drought, heat stress) these varieties may behave differently, so before the substantial planting it is expedient to carry out variety evaluations to avoid the later failures. The place of our experiments is located in the Nyírség representing adequately the ecological conditions of the surrounding areas, so the gained results can be adapted easily in the biggest apple production site of Hungary. Regarding the vegetative and the generative parameters of the 14 examined varieties (’Gala Venus Fengal’, ’Gala Decarli-Fendeca’, ’Galaval’, ’Jugala’, ’Gala Schnitzer (S) Schniga’, ’Red Cap Valtod (S)’, ’Early Red One’, ’Jeromine’, ’Crimson Crisp (Co-op 39)’, ’Red Topaz’, ’Wilton’s Red Jonaprince’, ’Red Idared’, ’Fuji September Wonder’, club cultivar) we found significant differences. The ratio of the thickness of trunk and the main branches showed that the trees have an optimal canopy structure in accordance with the Zahn principles, so they are in harmonious growing balance. The ‘Gala’ sport trained to slender spindle produced the highest yields, while the ‘Fuji’ and the ‘Red Delicious’ sport trained to super spindle can be described with the lowest values. All the cultivars reached the eating quality (65-70 mm), from which the ’Red Idared’, the ’Red Jonaprince’ and the ’Red Cap’ produced outstanding fruit size (81-85 mm).
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Review on rain induced fruit cracking of sweet cherries (Prunus avium L.), its causes and the possibilities of prevention
27-35.Views:740The rain induced fruit cracking is a big, serious and costly problem for cherry growers. Cracked fruits lose their value and they are not marketable because of the poor fruit quality. Cracked fruits have different storage diseases and shorter storage and shelf life.
There are many influencing factors of the cherry fruit cracking such as: water uptake; fruit characteristics (fruit size, fruit firmness; anatomy and strength of the fruit skin, stomata in fruit skin, cuticular properties, osmotic concentration, water capacity of the fruit pulp, growth stage of the fruit,); orchard temperature and other environmental conditions;
The most effective protection technique is the plastic rain cover over the tree rows. The installation of these equipments is too expensive for the cherry growers. That is the reason why researchers tried to find other less expensive and sufficiently effective ways against the Lim induced fruit cracking.
Several calcium formulas: calcium chloride (CaC1,), calcium hydroxide (Ca (OH)2) and calcium nitrate (Ca(NO3)2 ) can be sprayed in appropriate concentration. Spraying with other mineral salts (aluminium and copper salts, borax) and PBRs (Plant Bioregulators) may be also effective to reduce fruit cracking.
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Virus and virus-like diseases of grapevine in Hungary
25-36.Views:257Viruses and viroids are submicroscopic infectious particles which can cause disease symptoms on grapevine. These parasites are depending completely on the energy metabolism of the plant cell. To enter the host cell plant viruses depend on injuries or on transmission via invertebrates (insects, nematodes, etc.). Viruses are classified by many characters including particle morphology, host range and information content of the genome. At present about 70 viruses including 7 viroids infecting grapevine are known. In single or mixed infections they are potentially detrimental to the quality and quantity of grape production in any growing area of the world. Some viruses can cause severe economic damage in vineyards. In Hungary many important viruses and viroids have been detected in grape. This review summarises characteristics of viruses and the results of detection and characterization of virus and virus like diseases of grapevine in Hungary. The identification of the causal agent, its transmission, geographical distribution and the development of the diagnostic methods are also discussed.
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Translocation of diquat dibromide
105-107.Views:118The aims of our work were to answer the following questions: 1. Diquat dibromide at different concentrations is a contact or systemic herbicide? 2. if translocation occurs what is the extent and direction of it. 3. by what concentration it is translocated in hydroponics. It has been stated that diquat dibromide at different dilutions (40-5%) had systemic effect in Robinia pseudo-acacia in the fields. Its translocation has been occurred apically first, and later basipetally. The extent of translocation depended on the concentration. In hydroponics diquat dibromide has crytallized on the leaf surface of Galinsoga parvif lora and all concentrations (40-0.078%) proved lethal. Recognition and application of systemic characteristics of diquat dibromide is reported here for the first time. Improvement of application method is in the focus of our future work.
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Economics of sea buckthorn production and processing in Hungary
21-25.Views:268This study focuses on the business management-related advantages and disadvantages of sea buckthorn production and processing based on economic analyses. It is the main objective of the authors to identify the expected economic findings in a high standard plantation with different average yields. A deterministic model calculation was performed on the basis of technological processes, using the primary data collected from enterprises dealing with sea buckthorn production. The calculation is based on the assumption of a 10 hectare plantation with intensive production technology (high soil quality (golden crown value: 32 GC per ha), irrigation, high plant density per hectare). The cost and income relations and the long-term return of the plantation were examined in the case of different average yields (12 t ha-1, 18 t ha-1 and 24 t ha-1). Under the economic circumstances of 2016, the planting cost of an intensive plantation is around 4-4.1 million HUF ha-1. In the years following the fruit-bearing stage, direct production costs are between 2.5-3.9 million HUF ha-1, depending on the given average yield. On the contrary, 5.6-11.1 million HUF ha-1 revenue can be reached based on the current market prices, resulting in a gross margin of 3.1-7.1 million HUF ha-1. Under the modelled circumstances, return is realised on the plantation’s costs in 6-8 years. The net present value (NPVr=3.24%) calculated for the 15-year-long life cycle of the 10-hectare plantation is between 151-466 million HUF, while the internal rate of return (IRR) is between 23-45%. From the business management aspect, the advantage of sea buckthorn production is that it provides better income and return at a planting cost which is similar to that of other small fruits and berries. At the same time, the disadvantage of sea buckthorn production is the fact that yields are harvested every two years due to the technological characteristics of harvesting. The negative impact of this bi-yearly yield on liquidity can be eliminated with the so-called delayed planting.
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Modelling and comparing two canopy shapes using FEM
71-74.Views:112Central leader and Vase form canopy models were built using FEM. Their main characteristics were chosen to be the same. The models were virtually exposed to the effect of steady-state horizontal forced vibration in the frequency range of 0-20 Hz. Acceleration-frequency curves were calculated and drawn to find the best frequency values for the effective detachment and also to see the acceleration differences in the limbs. For the same purpose the direction of shaking was also changed. It was found that for the Central leader canopy shape multidirectional shaking would bring uniform detachment while for the Vase form trees also the unidirectional shakers were appropriate. The acceleration achieved for the Vase form models were much higher than for the Central leader type. The acceleration-frequency curve of the shaker unit can be used to find the best frequency for shaking.
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Improved clonal approaches to growing black locust (Robinia pseudoacacia L.) in Hungary: a case study
53-56.Views:238In Hungary black locust (Robinia pseudoacacia L.) is considered as an important exotic stand-forming tree species and due to climate change effects its importance is increasing in many other countries. It has some desirable characteristics from both the practical and research standpoints. As a result of a partly new black locust selection programme new black locust clones were improved and a technology was developed for mass clonal micropropagation of juvenile trees. Clone trials with micropropagated plants were established in the country for evaluating the juvenile growth and the stem form of promising black locust clones under marginal site conditions. Significant differences (P<5%) were found for stem form value which partly verified the genetic gain of the selected clones against the common black locust. It was also proved that tissue culture could offer partly new prospects for the rapid mass cloning of selected genotypes.
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Healthcare values and potential uses of the new Hungarian apple varieties on the basis on fruit analysis
25-28.Views:179Biological active compounds and valuable characteristics of some apple varieties and candidates were measured in our trials. Fruits of ’Rosmerta’, ’Hesztia’, ’Cordelia’ and ’Artemisz’ are recommended to enrich the Hungarian assortments for fresh consumption and choice of new tastes. Based on examined parameters it can be assumed that novel Hungarian resistant varieties are suitable for juice and fruit concentrate production, and due to high pectin content of their remaining pomace these varieties can be raw material of pectin production as well as they are also suitable for jam production mixed with other fruit species. Furthermore, functional food industrial product having high quality can be produced by using novel resistant varieties because of their high pectin and polyphenol content. Beside of their high market value their suitability for growing among orchard conditions is confi rmed by lower costs of production because of less plant protection treatments.
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The importance of Hungarian melon (Cucumis melo L.) landraces, local types and old varieties (Review)
83-87.Views:143While supermarkets devote whole aisles to hybrids, traditional varieties are hard to find, and becoming scarcer day by day. Unfortunately, countless old melon varieties have already been lost. Luckily we succeded in collecting most of these varieties, and thus conserving them in Gene Banks. Landraces, local types, and old breed races show many characteristics that could be useful in organic farming. It is important to get acquainted with these varieties and cultivars, because they have greatly adapted to the climatic and pedological conditions of the Carpathian basin. Therefore their conservation is essential for the protection of Hungarian genetic variability. With the help of utilising our landraces in organic farming; careful selection; and the usage of marketing strategy in order to enhance quality features, such as unique flavour; we could reclaim the one-time excellent reputation of Hungarian melon.
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Test of the utility of apple retrotransposon insertion patterns for molecular identification of 'Jonathan' somatic mutants
7-10.Views:171Up 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.
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First selections of the Hungarian apple breeding program for multiple resistance
9-13.Views:138The aim of the first Hungarian apple breeding program for multiple resistance started in the beginning of the nineties is to widen Hungarian apple assortment by good quality, resistant apple cultivars with excellent productivity and ecological capability to the most important fruit growing areas in Hungary. In the first years of seedling production we made early selection for susceptibility to apple scab in greenhouse. Alter this, field observation of susceptibility to powdery mildew, scab and canker and a yearly negative selection was carried on. From 1997, fruit quality was evaluated as well, and from 2001 the resistance of shoots to Erwinia ainylovora (Burrill/Winslow et al.) was examined using inoculations in greenhouse conditions. From the progenies of crosses in 1992 and 1993, six candidates were announced to national recognition out of hybrids examined for more than a decade. Descriptions of these selections from 'Prima' progenies and the most important data of their resistance, growing habit, morphological characteristics and fruit quality are shown in this article.
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Comparative study of the vegetative and generative organs in pear varieties
21-25.Views:118An assortment of 17 pear varieties was examined in 2006 at Keszthely, Department of Horticulture, Georgicon Faculty of Agriculture, Veszprem University. The selected varieties were planted in 1980, grafted on seedling rootstock and represented the majority of existing pear plantations in Hungary. The main objective was the determination of suitability of the most important varieties for the purpose of intensive growing technologies even when grafted on vigorous seedling rootstock. The most important growing and fruiting characteristics of the varieties have been assessed and evaluated from the point of view of productivity. We stated that the relations of the trunk or the main axis to the lateral branches and fruiting structures are all subject to varietal effects and are valuable indices of the growing character. The quotient of the diameters of trunk and branch should be around 0.3-0.4, and the relative frequency of fruiting structures (Dárda, nyárs, vessző) meaning the ability of branching and regeneration associated with accurate pruning policies are decisive from the point of view of promising success.
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Evaluation of essential oils by gas-chromatography and a new method: "electronic nose"
85-89.Views:141The chemical quality of the essential oils is determined by their composition as well as by the complex aroma features. For the evaluation of odour and aroma, sensory tests are practised, especially for applications such as aromatherapy, food industry or perfumery. In the recent studies we investigated eight Mentha origins (populations of Mentha iperita, M. spicata and M. arvensis) of our genebank collection using a new and effective instrumental sensory evaluation method parallelly with the usual GC analysis.
The results show that the examined mint clones possess different essential oil accumulation levels and special flavour characteristics, too. The GC analysis of the essential oil revealed characteristic differences at both inter- and intraspecific level in the proportion of mentol, menthon, carvon, limonene, menthyl acetate and in two not identified monoterpenes.
In the sensory tests the special complex aroma enables a reliable distinction with a single exception among the populations by the help of the "electronic nose" equipment. The distinction among the samples based on the sensor signals of the instrument — evaluated by multivariate methods — shows a close relation with the detected monoterpene components of the essential oil.
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Work quality assessment of a cherry sorting machine
57-62.Views:233The conditions of the cultivation of marketable cherries are diverse. Choosing the production site on the basis of the climatic conditions, selecting the most appropriate variety taking into account the region and the purpose of the production, utilization of the optimal production method, to ensure the required water and nutrients supply, frost and hail protection techniques, modern technology in crop protection, and professional performance of harvesting and handling, to name just a few of the most important issues. The objective of present study is to determine the qualitative characteristics of the UNITEC cherry sorting machine.
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Nutritional values of traditional open-pollinated melon (Cucumis melo L.) and watermelon (Citrullus lanatus [Thumb]) varieties
29-31.Views:218The aim of our experiments was to investigate the internal quality parameters of some old melon and watermelon landraces or varieties whether they have any desirable characteristics. Measurements were carried out using 8 different types of melon (Cucumis melo L.) and 8 accessions of watermelon (Citrullus lanatus [Thumb]), which were self pollinated under greenhouse conditions. Besides the determination of dry matter content; soluble solids, titratable acidity of the fruit juices, investigation of carbohydrates, total phenol content was measured by spectrophotometer. Total antioxidant capacities were determined spectrophotometrically using the FRAP method. We found some accesions both among melon and watermelon varieties, which could be characterized by outstanding inner content.
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Chemical characteristics of nectarine genitors used for breeding program in Romania
41-43.Views:117The geographic location of Bucharest area, the nature of its soil and its climate offer remarkably favourable conditions for nectarine growing, with juicy and well flavoured fruit, good for fresh consumption and processing.
The five years' investigation (1996-2000) has helped to identify some nectarine cultivars and hybrids (NJN 58, ARK 165, ARK 139, Morton, ARK 107, Romamer I, ARK 125, Firebrite) with exceptional fruit quality (dry matter content, titratable acidity, vitamin C content, overall sugar, and amount of pectic substances).
Dry matter content varied over the three years from 8.3 to 18.5% (NJN 68), meanwhile titratable acidity varied between 0.26 and 1.08% (Romamer I). Sugar / acidity ratio was within the limits of 8.6 and 36.5 (Nectared 7). Nectarines have high vitamin C content, over 10 mg/100g (Fairlane, NJN 67, Regina, Harko), glucides were found in Firebrite, Romamer I varieties and NJN 21, CIR1T127, HFSR3P4, HNA hybrids.
Some cultivars have been recommended for planting in this southern area of Romania (Crimsongold, ARK 125, Harko, Hardyred, ARK 134), others used as quality genitors (ARK 85, Nectared 7, NJN 21, ARK 21, ARK 134, Fantasia) in breeding projects.
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The after-effect of paclobutrazol on morphological characteristics of in vitro Narcissus poeticus ssp. radiiflorus plants
43-46.Views:178After different pre-culturing period (12, 23 or 34 days) on ½ MS medium with 1 mg l-1 paclobutrazol, 1 mg l-1 N6-benzyladenine and 0.1 mg l-1 1- naphthaleneacetic acid , 3 groups of Narcissus poeticus ssp. radiiflorus bulb scales were kept on the same medium without hormones. The results were evaluated monthly and the final one happened after 7 month. The best results were achieved due to the shortest pre-culturing period (12 days; Group 1), with 4.9 bulblets and 4.54% hyperhydricity. The result of the second treatment (pre-culturing period of 23 days; Group 2) was not different significantly but the number of bigger bulblet were higher (4.54 bulblets). After the longest pre-culturing period (34 days; Group 3), the number of bulblets was low (3.68) and more hyperhydricity (18.18%) was detected. The highest number of roots (13.91) was observed in this group
very likely due to the strong after-effect of paclobutrazol. -
Relations of phenometrical indices of apple fruits with weather variation in the assortment of varieties of an apple gene bank
115-120.Views:195The purpose of phenometry is to examine the measurable parameters of the plants in order to follow up the consequences of weather processes. We should fi nd the reasons, why the diameter of fruits grows larger in one season and smaller in the next. Variation may occur as a response to insuffi cient provision of water or nutrients, but also because of pathological effects and of extremely high or low temperatures, moreover, of extraordinary heavy fruit load. There are phenometrical characteristics, which consider the fi nal consequences (density of fl owers, fruits set, drop of fruits), whereas other parameters could be followed up (size, length and width of fruits) as the dynamic components of growth. The quantitative parameters of growth are functionally related to each other, where the weather conditions, soil humidity and nutrients are on the input side, thus it is possible to model the growth of fruits as a function of the environment. Initially, the relations between the main weather variables and the phenometrical data have to be cleared. In the present study, the interactions between the mentioned phenomena are presented and numerically defi ned.