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Improved clonal approaches to growing black locust (Robinia pseudoacacia L.) in Hungary: a case study
53-56.Views:286In 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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Fruit formation dynamics in parthenocarpic cucumber (Cucumis sativus L.) in spring forcing
111-114.Views:16820% of the cucumber crop of the world belongs to the parthenocarp type. Parthenocarp cucumber forcing has a great importance in Hungary, too. In our country the whole area of parthenocarp cucumber forcing was approximately 500 ha of the last years (2000-2002) and 75-85000 tons of yield has been harvested (MGYSZT, 2003). It means 15 — 17 kg/m2 as an average yield. In European forcing systems, parthenocarp cucumber is usually planted in January or February and it is harvested in spring or early summer. In Hungary cucumber forcing is the most profitable in two separate periods: spring and autumn, the reason for it is the changes of the average prices of fresh market cucumber, but spring forcing is still the most profitable. Forced cucumber cultivars are mostly parthenocarp; non-parthenocarp cultivars are grown in summer preferably. Cucumber cultivars, forced in our country, are hybrids, and 90% of them are offered by foreign seed companies (KristOfne, 1998.). The productivity of these hybrids is high and the productive period is quite short. All the mentioned details give the reason why it is important to know everything about the productivity, the dynamics of growth, and the possibilities of timing of parthenocarp cultivars, and it is also important to learn how to control all these parameters. Our spring cucumber-forcing experiment aimed to characterize of those parameters mentioned.
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Effect of reduced spray programmes on incidences of apple scab, powdery mildew and codling moth damage in environmentally freindly apple production systems
75-78.Views:737Still a large amount of pesticides and spary applications are used in environmentally friendly fruit production systems; therefore, the aim of our study was first to test the in vitro effeicacy of some fungicides against a key apple disease (apple scab), and secondly to evaulate the effectiveness of reduced spray programmes against apple scab, powdery mildew and coding moth in integrated and organic apple orchards. In vitro efficacy of 7 fungicides (Champion 50 WP, Kocide 2000, Nordox 75 WG, Olajos rézkén, Kumulus S, Rézkén, Rézoxiklorid) and another 6 fungicides (Score 25 EC, Efuzin 500 SC, Systane, Folicur Solo, Zato Plusz, Rovral) approved in organic and integrated production systems, respectively, were tested against apple scab. Altogether four spray programmes were performed i) standard integrated: sprays followed by forecasting systems during the season, ii) reduced integrated: sprays followed by forecasting systems but only 75% of the spray numbers used during the season-long spray programme, iii) standard oragnic: sprays applied every 7–14 days during the season and iv) reduced organic: 60% of the spray numbers used during the season-long spray programme. In vitro results showed that fungicides (with active ingredients of copper and sulphur) applied in organic production showed relatively high percent growth capacity of the apple scab fungus. Rézkén showed the highest and Kumilus S the lowest efficacy against apple scab. Fungicides applied in integrated production showed relatively low percent growth capacity of the apple scab fungus. Score 25 EC showed the highest and Rovral the lowest efficacy against apple scab. Field study showed that reduced spray programmes did not increase significantly scab incidence in the integrated field. However, scab incidence increased significanly (above 30%) in the reduced spray programme for the organic orchard.Mildew incidence was low (below 5%) in both integrated and organic spray programmes. Mildew incidence on both shoots and fruits increased significanly in the reduced spray programme for the organic orchard. Incidence of codling moth damage was affected the most by standard vs. reduced spray programmes. Though incidence remained below 10% in the integrated plots, the incidence was significantly higher in the reduced spray programme compared to the standard programme. Similar results were obtained for organic spary programmes, but the incidence was 10 times higher and the differences among the two programmes were larger.,
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The size of the canopy of sour cherry trees depends on the time of pruning
49-52.Views:175The intensive culture of sour cherry is achieved by training of trees to form smaller canopies not by means of dwarfing rootstocks but by growth moderation techniques. The rootstocks traditionally used cause vigorous growth, and it is up to the technology to apply procedures less utilised earlier for that purpose. One of those techniques is the transfer of hibernal pruning to the estival period. The best term of the latter is the period of 1-3 weeks after fruit harvest.
The prolongation of the period of favourable illumination and the reduction of the canopy size facilitate higher densities of planting (number of trees per hectare) and a better exploitation of the crown (specific yield). The regular use of summer pruning resulted also in a better quality of fruit.
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Eco-friendly methods to control infection of Botrytis cinerea during propagation of grapevines
53-56.Views:319Grey mould (Botrytis cinerea Pers.) is a pathogenic fungus which causes damage to the production of grapevine nursery plant materials especially on the stored canes or on graftings during the callusing period. The conditions, increased temperature and humidity, are ideal for the pathogen during the pre-forcing stage and in the storage Botrytis cinerea can easily infect the outbursting buds as large amounts of grapevine canes are stored in a relatively small place. The fungicide-based management is general in the prevention of gray rot infection but the palette of authorised chemical compounds is narrowed year by year due to the regulations of the European Union. Our aim is to develop an eco-friendly method which combines the use of natural materials with techniques used in organic farming. Effect of the ultraviolet-c light on the Botrytis cinerea was studied. The development characteristics of the pathogen were examined under daylight and dark conditions and experiments were set up with cow’s milk and acetic acid. UV-C light destroyed the developed conidia, however, the radiation stimulates the development of immature propagules. Larger quantities of conidiophores and conidia were formed in daylight compared to culture in the dark, while different conditions did not signifi cantly change the mycelial growth characteristics. The developed bacteria prevented the spread of pathogen mycelia during the test with cow’s milk in Petri dishes, although the smooth development of propagules that occurred did not change the vitality of the fungal colony. Furthermore the growth of Botrytis cinerea fungus mycelia was strongly inhibited by acetic acid.
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Vegetative parameters of sweet cherry (Cerasus avium L.) cultivars in two training systems
42-45.Views:340Hungarian sweet cherry production has been changed recently. Thanks to the favourable selling prices many new plantations were established in the last years. In the new orchards mainly spindle canopy are trained, although many type of crown forms are used all over the world. In our study slender spindle and bush canopy were evaluated with three cultivars (‘Petrus’, ‘Vera’, ‘Carmen’) grafted on Prunus mahaleb rootstock. Vigor of the 3-4 years old trees showed spectacular differences. The highest vigor with Spanish bush was found for cv. ‘Vera’, but on slender spindle canopy the thickness values were medium. Meanwhile cv. ‘Petrus’ showed the highest trunk thickness with spindle canopy, but the lowest with Spanish bush. On spindle canopy cv. ‘Carmen’ presented the highest ramification ability, but its 2-3 years old twigs started to bald very early, which can be considered an unfavorable phenomenon. Bush canopy still can be described with strong vegetative growth on 3-4 years old trees, as vigor of spindle trees are more moderate.
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Pruning of plum trees and maintenance of balanced yielding
131-138.Views:252In this review, we give an overview of the pruning techniques that should be applied in commercial plum orchards. First, a detailed description of pruning for shaping the different crown types for the first, second, third, fourth and fifth years and the phytotechnical works is given for crowns with a circular projection area. Then, pruning for open crowns forms, such as the vase form is discussed. Following the shaping of the crown, it should be maintained by pruning. Detailed information is given on pruning for maintenance with special emphasis on the comparison of winter and summer pruning. In the following part of the manuscript, pruning experience is described separately for the major commercial plum cultivars in Hungary such as Cacanska lepotica, President, Bluefre, Stanley. Recommendations for cultivation systems under non-irrigated conditions are also included. Finally, light requirements, growth characteristics and suggested crown forms of the different cultivars are described for cvs. Ageni, Althan Tingle), Besztercei szilva Nm. 122, Bluefre, Cacanska lepotica, Cacanska rodna, Debreceni muskotály, Montfort, President, Ruth Gerstetter, Sermina, Stanley, Tuleu gras and Zöld ringló).
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Factors affecting rhizogenesis in vitro and acclimatisation of three cherry rootstocks
40-46.Views:135Factors affecting rhizogenesis in vitro and acclimatisation of three rootstocks of cherry, i.e. Mahaleb, Maxma-14 and Weiroot -10 were investigated.
Rooting was easily achieved within 2-4 weeks on MS-based liquid or agar-gelled media containing auxins IBA at conc. 0.49 or 2.45 pM or NAA at conc. of 0.49 pM. On liquid media with 2.45 pM IBA, a maximum rooting efficiency of 95-100% was obtained. However, high concentrations of auxin delayed the time of root initiation for 3-5 days.
Rooted plantlets were transplanted into pots with a mixture of 3:1 (v/v) peat:perlite and acclimatised gradually to field conditions with efficiency of 60%.
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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:853The 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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Nutrient demand of stone fruits
19-23.Views:155Effects of nitrogen, phosphorus and potassium fertilization were investigated on the change of nutrient content, vegetative and generative production of apricot, peach and sour cherry trees, as well as on frost hardiness in long term experiments. Nitrogen and phosphorus fertilization increased only the concentration of these elements in cherry leaves without effect on growth and yield. Consequent potassium effect was proved on these stone fruit species. Effect on yield appeared following the first higher crop load.
Potassium supply has positive effect on frost hardiness of apricot and sour cherry flowers and peach flower buds.
In peach, the lime content of soil decreased the yield but it could be compensated by potassium dressing to some extent. Favourable nutrient boundary values were determined for soil and foliage.
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Role of hydrogen peroxide and Pharmaplant-turbo against cucumber powdery mildew fungus under organic and inorganic production
39-44.Views:473Cucumber leaves have been sprayed with a solution of hydrogen peroxide (H202) or Pharmaplant-turbo combined with organic or inorganic fertilizers under plasic house. Under the influence of H202, leaves exhibited resistant against Podoshaera fusca fungus, the causal agent of cucumber powdery mildew. H202 (15 mM) was able to decrease the disease severity from 90.4% to 12% in two experiments conducted in two seasons. Pharmaplant-turbo (Turbo) is new chemical compound and used as an antifungal compound. Turbo in 1 ml/L was able to decrease the disease severity from 90.4% to 11.5% in the both experiments as well. Both of H202 and Turbo were combined with organic treatment (compost + compost tea + seaweed extracts) which showed significant effect against cucumber powdery mildew fungus and strongly suppressed it as compared to control leaves. Organic treatment produced higher vegetative growth characters and greater early and total yields as compared to inorganic treatment, also organic fruits produced the lower nitrate content and the higher ascorbic acid content as compared to inorganic fruits. Our study have indicated that, H202 and Turbo combined with organic fertilizers play a role in the resistance of cucumber against powdery mildew by decreasing the disease severity. We suggest to give more attention to the direct application of H202 in low concentration and Turbo against powdery mildew diseases and other plant diseases.
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Bee pollination and association of apricot varieties
20-24.Views:258Apricot yields are highly variable according to the season. The variation is caused mainly by the adversities during the critical processes of floral biology, i.e. blooming and fertilisation. On the basis of information concerning blooming time and mutual compatibility relations of apricot varieties a system of securing regular and adequate yields has been developed.
Winter frosts of the continental type are well tolerated by most of the apricots, however, after the end of rest period, flower buds are loosing frost tolerance, 'rapidly.
Being one of the fruit species blooming earliest during the early spring, apricot start to bloom in Hungary around the end of March or early April as a mean of many years, but it also happened, exceptionally that apricot started to bloom at February 20 (at Letenye South Hungary). The early season, exposes the floral organs to frost injuries. As a consequence, apricot orchards on the Great Plain produce low yields in 3 years, intermediate yields in other 3 years out of a ten-year-period.
Moreover, weather conditions during the blooming period are often unfavourable for pollination. Cool, windy and rainy weather prevents the flight of insects and on the other hand, warm spells shorten the blooming process, nectarines and stigmata get dry and the female gametes loose viability before effective pollination occurres.
The fertility of individual cultivars are meeting different obstacles. Apricot cultivars differ greatly in the rate of flowers bearing underdeveloped pistils, which may attain even 60% (e.g. Orangered). New commercial cultivars are often self-incompatible. Local varieties of that type in Hungary are the „óriás" varieties (e.g. Ceglédi óriás, Szegedi mammut), and the new hybrid Ceglédi Piroska. Many of the cultivars are variable in their self-fertility (partially self-fertile): Budapest, Harmat, Korai piros, Mandulakajszi.
Inter-incompatibility is also known in apricots. The „óriás " varieties do not fertilise each other. During the growth of fruits, cool spells (2-4 °C) caused severe fruit shed in Ceglédi óriás.
Apricot flowers produce pollen and nectar at average rates related to other fruit species, thus bees are attracted sufficiently. Bee visits are very variable according to growing site and season. Most of the bees are pollen gatherers but sometimes nectar suckers are in majority. Bee pollination is necessary not only for the self-incompatible varieties but also to enhance the yield of self-fertile varieties.
Taking the blooming and fertility relations of the cultivars into account, plantations should not exceed two rows to a particular self-incompatible varieties, and possibly two different polliniser varieties are suggested to be planted as flanking the block in question.
In commercial plantations 2 to 4 bee colonies per hectare are proposed to move for the whole blooming period.
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Morphological characterization of shallot (Allium cepa L. var. aggregatum) segregating populations obtained from natural-outcrossing in Ethiopial-outcrossing in Ethiopia
74-83.Views:70Shallot is a vegetable and condiment crop widely used in Ethiopia and globally. However, absence of improved and adaptable varieties has been the major cause of low productivity. Narrow genetic base of local shallot germplasm owing to vegetative reproduction of the crop, among others, has been the root cause of low productivity. Nevertheless, some plants within the germplasm were observed bolting and producing viable seeds, presenting an opportunity for genetic diversification. Consequently, a germplasm enhancement program was initiated using these naturally outcrossing genotypes where about eighty-one genotypes were generated. The present study was thus undertaken with the objective of characterizing, classifying, and selecting the eighty-one genotypes for future breeding activities. The genotypes were planted in 9x9 simple lattice design with two replications at Debre Zeit Agricultural Research Center (Ethiopia) during the dry (irrigated) season of 2021. The genotypes were evaluated for fifteen growth, yield, and quality traits. Significant variations were observed among the genotypes in terms of bulb yield, bulb height and diameter, total soluble solids, bolting percentage, and bulb skin color. Bulb yield of the genotypes ranged from 31.33 t/ha in DZSHT-79-1A to 9.63 t//ha in DZSHT-45-1A-1. DZSHT-51-2 (207.93 g) was the highest yielder per plant whereas DZSHT-065-6/90 (74.51 g) was the lowest yielder. DZSHT-14-2-1/90 had the thickest bulb (44.69 mm) significantly thicker than twenty two genotypes which had bulb diameter ranging from 28.92 mm to 20.29 mm. DZSHT-81-1/90 was a genotype with the longest bulb height (52.33 mm) while DZSHT-147-1C was a genotype with the shortest bulb (33.12 mm). DZSHT-307-1/90 had the highest TSS (16.78°Brix) significantly differing from DZSHT-002/07 which had the lowest TSS (11.17 °Brix). Dry matter of the genotypes ranged from 12.00% to 22.79%. DZSHT-004/07, DZSHT-111-2-1, DZSHT-41-2B and DZSHT-72-2 had DM% greater than 20% which coupled with greater than 14 °Brix could make them suitable for dehydrated shallots. Among the 81 genotypes characterized 4 (4.9%), 7 (8.6%), 13 (16.1%), 28 (34.6%) and 29 (35.8%) were yellow, golden, light red, red and dark red in colour, respectively. Fifteen of the genotypes had at least 50% bolting plants whereas twenty nine of the genotypes had less than 25% bolting. The results revealed that seven principal components explained approximately 76% of the observed variation. Cluster analysis grouped the genotypes into seven clusters, with the majority falling into three clusters. The study successfully identified genotypes with diverse and important traits and availed both the genotypes and the information for future breeding programs. These genotypes could be used for the development of improved hybrid and open pollinated shallot varieties with higher yield, quality and pest resistance/tolerance attributes.
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Estimating of water consumption of cherry trees
15-17.Views:210Despite 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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New sweet cherry cultivars in intensive plantings
13-16.Views:390The study took place in the largest sweet cherry plantation in West Hungary. The purpose has been the identification of those varieties, which will be suitable for intense cultivation, early fruiting and excellent fruit quality, moreover, the selection of the optimal phytotechnical procedures. At the same time, scion-rootstock combinations have been tested also from the point of view of growing intensity and fruiting in high-density plantation. The dense planting is induced to start fruiting early and yield regularly by special methods.Yielding was stimulated by maintaining the balance of vegetative-generative growth by binding the shoots, by summer pruning, by cuts on the trunk and root pruning. Best experiences have been found in yield and quality in the following varieties: Canada Giant, Carmen, Firm Red, Giant Red, Katalin, Kordia, Regina. Dense planting has been feasible also on vigorous rootstock, like P. mahaleb. Dwarfing rootstocks like P-HL-A, Gisela 6, accelerate the formation of flower buds and yielding earlier with fruits of adequate size. ‘Firm Red’ and ‘Giant Red’ excelled with their large fruit (>27 mm diameter) in all combinations, thus being promising under Hungarian conditions.
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Evaluation of hot pepper (Capsicum annum L.) varieties for green pod yield and quality under rain fed production at Teppi, South Western Ethiopia
45-49.Views:244The trials were designed with three replications in a randomized complete block design in order to evaluate the phenological, growth and yield potential of hot pepper varieties such as ‘Mareko fana’, ‘Melka Zala’, ‘Melka Awaze’, ‘Melka Shote’ and local check. Significant difference was observed between growing year and used varieties. The varieties also performed significantly different (p<0.05) for most of the considered traits in the study. The result revealed that varieties ‘Melka Zala’, ‘Mareko fana’ and ‘Melka Awaze’ were scored highest green pod yield of 8.39, 8.71 and 11.39 ton per hectare, respectively. However, ‘Mareko fana’ variety was susceptible to disease attack as compared to other varieties. Therefore, promoting both ‘Melka Awaze’ and ‘Melka Zala’ varieties for widespread production for Teppi and the areas with similar agro-ecological conditions could contribute to boost the productivity of hot pepper. ‘Mareko fana’ could also be used for dry pod purpose due to its attractive color.
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Sunburn incidence of apples is affected by rootstocks and fruit position within the canopy but not by fruit position on the cluster
45-51.Views:278Authors investigated sunburn incidence of apples on the combinations of three different growth inducing rootstocks (M.9,MM.106 and seedling) and five varieties (‘Smoothee’, ‘Golden Reinders’, ‘Granny Smith’, ‘Gloster’ and ‘Jonagold Jonica’). Symptoms were classified as sunburn browning, sunburn necrosis and photooxidative sunburn. The frequency of symptoms was recorded at various parts of the canopy (N, E,W, S, and lower canopy, upper canopy) and on the cluster (terminal, lateral). Cultivar susceptibility varied between 0.30 and 5.65% on M.9 rootstock, ‘Granny Smith’ seemed to be the most susceptible cultivar whereas relatively low percentage of damaged fruit was observed for ‘Gloster’. On MM.106 and seedling rootstocks, damage level was significantly lower than on M.9. Remarkable differences were not observed in the share of the three sunburn types between cultivars. The most common symptom observed was sunburn browning. Far less fruit was affected by sunburn necrosis and photooxidative sunburn. Photooxidative sunburn symptoms were not found on ‘Granny Smith’ and ‘Gloster’ fruits on MM.106 rootstock. Latter cultivar did not show sunburn necrosis symptoms either. With increasing growing vigor of the rootstocks the share of sunburn browning increased. Fruits with sunburn symptoms were found in a great majority on theW quadrant of the trees. This was true for all cultivars. Remarkable differences in the location within the canopy of affected fruits between the three types of sunburn were not observed. Specific distribution of sunburned fruit was observed along the vertical axis of the canopy, too. Most of the damaged fruit were found in the upper canopy. This is particularly true for trees on vigorous stocks such as MM.106 and seedling. On M.9 rootstock, depending on cultivars 5.9 to 38.9% of sunburned fruit was located in the lower canopy. Most common symptom in the lower canopy was the sunburn browning, however symptoms of sunburn necrosis were not found at lower canopy level. Low rate of photooxidative sunburn was observed such lower canopy conditions. Sunburn incidence was very similar on king or side fruit. Significant differences were not found in the share of each sunburn types between fruit positions on the cluster. This was not influenced by rootstocks either.
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Mutation induction in sweet basil (Ocimum basilicum L.) by fast neutron irradiation
30-38.Views:381Basil species are highly sensitive to exterior environmental conditions and its consequences lead to great economic and agronomic losses. In this research, a mutation method was optimized out for creating a new variety of Ocimum basilicum L., which could tolerate the extreme/extraordinary climatic circumstances or biotic stresses, such as fungal diseases. Fast neutron irradiation was performed on the Hungarian commercial variety seeds with doses of 5 to 60 Gray and grown into fully developed plants. Numerous phenotypical changes like deformed congestion, leaf mutation, and low growth occurred, especially at higher dosages. Then to confirm whether the plantlets had mutation or not, and to detect the molecular variation and relationship, fingerprinting profiles of the developed mutant regenerants and donor plant have been assessed using ISSR markers. 115 loci were yielded, ranging from 0.2 to 1.5 kb, out of which 110 loci were polymorphic in nature, representing 95.6% polymorphism. The most suitable primer to determine the genetic diversity within the Ocimum species was the UBC-856 with 0.42 PIC and 4.1 MI values.
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Carbohydrate utilization of Erwinia amylovora in vitro
31-34.Views:188Nectar is a multi-component aqueous solution that promotes bacterial multiplication. The concentration of nectar in plant flowers is not stable since it is under the influence of environmental conditions, especially free moisture and relative humidity. Experiments were conducted with "artificial nectar" and directed along two lines: (1) determination of the optimal concentrations of carbohydrates for the growth of E. amylovora development (2) consumption of different carbohydrates besides basic sugars.
Solutions of "artificial nectar" were prepared in different compositions by changing the dominance of basic sugars (fructose — glucose —sucrose) in proportions of 2:1:1, 1:2:1, 1:1:2 and between concentrations of 10-0.6% (diluted with Basal minimum broth) in order to determine optimal conditions for the development of E. amylovora.
At a basic sugar concentration of 10% bacterial multiplication started and continued until I log degree (from 106 to 107 cfu/ml). At concentrations of 5% and 2,5 % cells developed with nearly the same kinetics (from 106 to 8x107 cfu/ml and from 106 to 9x107 cfu/ml, respectively). Multiplication was more pronounced and nearly the same at concentrations of 1.2 % and 0.6 % (from106 to 2x108 cfu/ml). At a basic sugar concentration 30% total sugars bacterial multiplication did not occur, while at 20 % it was negligible, not measurable photometrically.
At minimal concentrations of F, G, S (between 1-0.1 %) bacterial cells were still able to multiply, producing organic acids from sugars.
Our study showed that E. amylovora requires only a small amount of sugars (0.1%) for multiplication (acid production) while high concentrations inhibit multiplication. There was a negative correlation between sugar content and cell density. The optimal range of sugar concentration was at about 1%.
Effect of "less frequent carbohydrates" to E. amylovora multiplication was also determined using the API 50 CH strip. We could provide information on utilization of 39 carbohydrates by the bacterium at different categories as follows: Not utilized-, Slowly and weakly utilized-, Slowly and completely utilized-, Quickly and completely utilized carbohydrates. We suppose that carbohydrates that belong to the latter two groups could play an important role as nectar components in promoting E. amylovora multiplication in the blossoms of pome fruit trees.
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Sustainable food production with greenhouse technologies
99-105.Views:224The greenhouse fruit and vegetable production is one important area which supports sustainability. To achieve
sustainable economy and growth, the given natural resources have to be used in a smarter, renewable way in order to avoid
depleting them. New technologies and new methods are developed and implemented to utilize resources in more optimized way.
Sustainable food supply is essential globally for the world, however it has to be managed and achieved on local levels. We present
the greenhouse production market restructuring with new players. What kind of difficulties arise in the open field vegetable
production and what benefits can be realized by the customers and producers from the covered greenhouse technology in the
continental and desert climate? What are the technical boundary conditions to establish and operate greenhouse production in
different regions and what are the benefits realized from local food production? As an example, we analyse Qatar’s energetics,
climate conditions and food resources, Qatar’s food supply process and its barriers. We will show how the sustainability and
food safety appear in Qatar’s National Strategy Plan. -
A study of processes active in regeneration of different sweet cherry varieties
55-57.Views:232Cherries belong to the group of fruit trees, which require little attention in pruning. The process of getting bald branches is less accentuated, which is associated with the light requirement of organs changing along with the aging process. The growing habits of the varieties (length and number of growing shoots, etc.) is closely related with the productivity of fruiting parts. The ability of regeneration and the functional effectiveness of fruiting structures are expressed by the distribution according to their age. The differences registered justify the necessity to develop pruning policies for each particular type of variety. For that purpose, we have to examine the age dependency of the processes related to regeneration, which may serve as starting point of a pruning strategy. Growth of some parts should be stimulated in order to develop or regenerate fruiting parts. Some branches need to be rejuvenated, partially, as an antidote to progressive senescence. Every intervention is aimed to strengthen the development of the most productive constructions. Reactions induced by rejuvenation should be expressed in fruiting intensity. A pruning program adapted to the particular variety as well as to the actual phase of a rotating pruning system should anticipate results.
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Effects of different pollination treatments in genotypes of Prunus salicina Lindl.
141-146.Views:128The low productivity in the Japanese plum (Prunus salicina Lindl) is related with self-incompatibility characteristics, so other species or varieties that act as pollinators need to be present to improve fruit production. The objective of this work was to study the efficiency of pollination in different genotypes of P. salicina using treatments of natural self-pollination, cross-pollination with P. armeniaca cv. Giada and open pollination. These treatments were evaluated through viability techniques and in vitro and in vivo germination of pollen grains; the growth of pollen tubes along the pistil was also observed. Genotypes used in this study showed differences for each one of the pollination treatments. Some genotypes showed signs of self-sterility and interincompatibility with P. armeniaca cv. Giada, while others showed partial self-fertility characteristics or pseudocompatibility. Moreover, some genotypes showed a higher affinity coefficient with cv. Giada and these will be indicating a possible intercompatibility. These studies will be an important contribution breeding and selection of intra and intercompatible genotypes to be used in commercial orchards.
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Experimental approach in apple tree nutrition
9-13.Views:134Authors present synthesis of experimental work, performed in the last decades, for better understanding nutritional behaviour of apple trees and related problems in fruit quality. There were evidences supporting possible deteriorating role of potassium in feeble physiological status of apples, if applied in excess. More intensive studies proved that higher potassium uptake into leaves and fruits might be also the result of increased sink power of individual fruits. Nevertheless early senescence of apples during storage and also sensibility to bitter pit were successfully related to the increased sink power of fruits, casual relations in excessive NPK fertilization, although increase in sink power need further investigations. Impaired weather conditions during early development of fruits, hostile orchard practices in pruning, thinning, irrigation and also unskilled application of growth regulators may also contribute in the enhancement of sink power and in weakened physiological status of apple fruits.
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Effect of N, P, K and Mg fertilizers on some vegetative and generative parameters of a sweet cherry cultivar
27-30.Views:458This two-year-study was aimed to provide results on the effect of nitrogen, phosphorus, potassium and magnesium fertilizer treatments (control, NP, NPK, NPKMg) on vegetative and generative features of the sweet cherry cultivar ‘Carmen’. Examinations were performed in an orchard planted in 2012 on Prunus mahaleb rootstock with spacing of 5 x 2.5 m. All treatments improved the vegetative features of the sweet cherry trees in both years of 2016 and 2017. Fertilizer treated trees increased trunk cross section area (TCSA) with 51.3-63.1%, while control trees showed 48.3% trunk growth increase. Yields of control trees were lower in both years (5.9-7.2 kg/tree), than that of the fertilized trees (7.8-11.3 kg/tree). Treatments also increased the phosphorus (16-22%), magnesium (12-20%) and potassium content (3.5-18%) of the fruits compared to control treatments.
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The comparison of several soil cultivation methods in the Tokaj-wine region
35-37.Views:214Our results show that the different cultivation methods have higher effect on the yield than on the grape quality. In 2007 the weather was extreme dry (from May to August only 195 mm precipitation was recorded) the straw mulch proved to be the best solution regarding the yield and the grape quality. Although no significant differences were observed in the sugar- and titratable acidity content of the must, the ratio of noble rotted berries was higher on the straw mulched plots. Straw mulch could conserve the moisture content of the soil and it seems to be contributed to the conformation of suitable microclimate for Botrytis infection, but for long distance conclusions further examinations need to be investigated. The less yield and ratio of rot was observed in case of barely covered vines and the vegetative growth of the grape was less intensive in case of these vines.