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Investigation of Potato (Solanum tuberosum L.) Salt Tolerance and Callus Induction in vitro
51-55Views:97Potato production plays an important role in Hungary and the other countries of Europe. Consumption of potato products has increased to a large extent during the past several years. We can satisfy market demands with high quality and virus-free varieties.
Results of potato production depend on tolerance/resistance to abiotic stresses. In many cases, increased concentration of NaCl causes yield loss. Selection of salt tolerant varieties proved to be a difficult problem. Nowadays, the salt tolerance of potato varieties can be determined by cell/tissue/ protoplast techniques. Somaclonal variation provides a great potential for selection of lines resistant to salt stress. In vitro shoots and callus, derived plantlets selected for salt tolerance/resistance provide material for micropropagation.
In vitro shoot development of potato (Solanum tuberosum L. cv. Kuroda) was investigated under salt stress (40 mM, 80 mM, 120 mM NaCl) conditions. Shoot heights of plantlets cultured under salt conditions were lower than the control through the investigation. However, the shoot development of plantlets originated from in vitro meristems was almost at the same level as the control under 40 mM NaCl concentration.
There was no significant difference in the in vitro biomass production between control and treatment with 40 mM NaCl concentration. We measured a significant decrease in dry-matter mass under 120 mM NaCl concentration. There is a need for more investigation of different genotypes and for a conclusion as to whether in vitro tolerance could occur under in vivo circumstances in plants originated from somaclones as well.
Under in vitro conditions, we investigated shoot and leaf callus initiation using different culture media with different 2,4-D concentrations. Under dark conditions, callus induction of shoot/leaf decreased as the 2,4-D concentrations increased.
In light conditions, there was a little callus induction, while callus initiation from the shoot from 5 μM to 12 μM 2,4-D concentration showed a significant increase -
Development of a New Maize (Zea mays L.) Breeding Program
25-30Views:101Genetic manipulation may not replace any conventional method in crop breeding programs, but it can be an important adjunct to them. Plant regeneration via tissue culture is becoming increasingly more common in monocots such as corn (Zea mays L.). In vitro culturability and regeneration ability of corn decreased as homozigosity increased, which suggested that these two attributes were controlled primarily by dominant gene action. Pollen (gametophytic) selection for resistance to aflatoxin in corn can greatly facilitate recurrent selection and screening of germplasm for resistance at a much less cost and shorter time than field testing. Integration of in vivo and in vitro techniques in maize breeding program has been developed to obtain desirable agronomic attributes, speed up the breeding process and enhance the genes responsible for them. The efficiency of anther and tissue cultures in most cereals such as maize and wheat have reached the stage where it can be used in breeding programs to some extent and many new cultivars produced by genetic manipulation have now reached the market.
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Micropropagation of Leuce-poplar clones and its role in selection breeding
43-48Views:162Leuce-poplars (mostly white poplar and its natural hybrid grey poplar) are native tree species trough Hungary. They are covering more than 4.0 per cent of the Hungarian forested area (77 000 ha). The white (grey) poplars play a significant role in the forestation under sandy soil site conditions as well as they are of importance from nature conservation point of view as well.Long-term selection breeding work is going on at the National Agricultural Research and Innovation Centre Forest Research Institute (NARIC FRI), involving selection of fast-growing Leuce-poplar clones under dry site conditions.Micropropagation technology is relatively quickly spreading in forestry. In vitro multiplication of trees is applied mainly in fruit growing in Hungary, in case of forestry it is used mainly for selection breeding.This paper presents a short overview on the micropropagation trials with different Leuce-poplar clones and the early evaluation of the seedlings growing of the micropropagated clones/varieties. -
Examination of different fungicides against Macrophomina phaseolina in laboratory conditions
65-69Views:144In Hungary, sunflower is the third most important arable crop, which has a lot of pathogenic fungi. One of these fungi is the Macrophomina phaseolina, which is a well-known fungus in all over the world, since this pathogen has more than 700 host plants. In Hungary, several host plants can be found as well. The M. phaseolina produces microsclerotia, which can survive in the soil and residues for almost 10 years. For now, there is no efficient treatment against this pathogen because of this fungus, since it is extremely resistant and cannot be destroyed easily. The only effective treatment against the fungus is genetic defence. In this study, three different fungicides were tested in vitro against the fungus. The Mirage (prochloraz) seemed to be the most effective fungicide as it completely arrested the hyphal growth. In contrast, the Amistar Xtra (azoxystrobin and ciprochonazol) has only a minor effect on the growth of M. phaseolina. Thirdly, the Retengo (pyrachlostrobin) arrested the hyhpal growth of the fungus with 71% at 100 ppm, in other words, the use of this fungicide seems promising.
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Micropropagation of Rudbeckia hirta L. from seedling explants
53-59Views:93We conducted experiments for developing an in vitro micropropagation protocol starting from meristems of Rudbeckia hirta L seedlings. We pre-soaked the seeds in sterile ion-exchanged water for 17 hours, and then achieved surface disinfection in two separate steps. First, we used concentrated household sodium-hypochloride solution for 20 minutes and, also for 20 minutes, we applied hydrogen peroxide of 10%, which was followed by washing with sterile ion-exchanged water three times. For the propagation of seedling meristems, the combination of half-strength solid Murashige and Skoog (1962) culture medium containing 10 mg/l of kinetin and 2 mg/l of kinetin + 0.1 mg/l of 2iP proved to be the most suitable. The average number of shoot-buds developed from the seedling axillary meristem in the best culture media varied between 5 and 17. Without separating them, we inoculated the shoot-bud clusters on MS culture medium containing 2 mg/l of IAA. After four weeks of incubation, we obtained elongated shoots, which we separated and inoculated into a new culture medium and from which we obtained elongated roots. The rooted plants were gradually acclimatised in the cultivation room, potted and carried to a greenhouse, and then planted in open field for subsequent observation. By adopting this method, our laboratory started the micropropagation of the superior and/or elite genotypes of the Rudbeckia hirta L. being of special value in respectt to breeding.
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Preliminary studies on in vitro sensitivity of Venturia inaequalis populations to some fungicide active ingredients
165-168Views:108Aim of this study was to investigate the sensitivity of conidia of Spilocaea pomi to main fungicide active ingredients (cyprodinil, pirimethanil, fluquinconazole, tebuconazole, difenoconazole, dodine és trifloxistrobin) at dosages of 0.5, 1 and 2 times incubated in vitro at 24 and 48 hours collected from three integrated apple orchards. Results showed that degree of conidial germinations at the fungicide treatnemts decreased in the order of dosages of untreated, 0.5, 1 and 2 times. Considerable conidial germination was observed at higher dosages of some fungicides (e.g. groups of strobilurines and EBI) which confirmed the possibilities of sensitivity reduction of Spilocaea pomi to some funigicides in the sampled Hungarian apple orchards.
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Cytokinin and auxin levels in micropropagating Red Fuji and McIntosh apple varieties
53-59Views:102Effects of media hormone content on in vitro shoot multiplication and rooting were examined in cv. Red Fuji and McIntosh apple scions. Multiplication responses of shoots to different concentrations (0.5 and 1.0 mg/l) of 6-benzylaminopurine and 6-benzylaminopurine riboside were tested at two levels (0.1 and 0.3 mg/l) of indole-3-butyric acid. The best proliferation rate was achieved on medium containing 1.0 mg/l 6-benzylaminopurine and 0.1 mg/l indole-3-butyric acid in cv. Red Fuji (5.3) and on medium containing 1.0 mg/l 6-benzylaminopurine and 0.3 mg/l
indole-3-butyric acid in cv McIntosh (10.3). The length of shoots on these media was enough for rooting (38.4 mm in cv. Red Fuji and 39.3 mm in cv McIntosh). Shoots developed on the best proliferation medium were used for rooting. Effects of different concentrations of auxin in the root induction media and presence of activated charcoal in the root elongation media were examined on rooting capacity. The best rooting rate (100% in cv. McIntosh and 83% in cv. Red Fuji) was achieved when the root induction medium contained 1.0 mg/l indole-3-butyric acid. In general, rooting was inhibited in the presence of activated charcoal. Because of high in vitro multiplication and rooting rate and high percent of survival during acclimatisation, the methods described here make effective micropropagation processes possible for cv. Red Fuji and McIntosh. -
In vitro analysis of the effect of ragweed extract against Monilinia laxa
117-120Views:109Nowadays in Hungary nearly 5 million hectares of agricultural area was infected with ragweed (Ambrosia artemisiifolia). According to the public opinion the ragweed is a weed. From agricultural and public health point of view it is exceptionally dangerous plant. As it contains a number of useful active ingredients, based on this the ragweed is consider a medicinal plant. Our goal was to present that the ragweed contains antifungal active substances as well. In the experiments we used the pre-flowering plants with roots and we extracted the biological active components of dried plant. We tested the biological activity of the extracts against Monilinia laxa in vitro. We related based on our examination that ragweed contains biologically active agents, by which it is hampered the reproduction of the Monilinia laxa.
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Usability of vegetable extracts in the protection against Alternaria alternata
113-116Views:139In our country, wormwood ragweed (Ambrosia artemisiifolia) may cause serious problems. Nearly 5 million hectares of agricultural area was infected with ragweed (Ambrosia artemisiifolia), which is believed useless weed. Allergological point of view, most problematic weeds adventive. However, many physiologically very beneficial compound also included, those with the effects have been known also by the Indians. On this basis, herbs can be thought of as ragweed. Our goal was to present that the ragweed contains antifungal active substances as well. In this paper we tested the biological activity of the extracts against Alternaria alternata F.00750 in vitro. We related based on our examination that ragweed contains biologically active agents, by which it is hampered the reproduction of the Alternaria alternata. The minimum effective concentration was 300 mg extract in a Petri dish, which was three days inhibited the growth of fungus. Full fungicidal effect was observed over dose 525 mg.
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Sour cherry anthracnose and possibilities of the control with special regard to resident Glomerella population in sour cherry plantations of East Hungary
12-17Views:139Anthracnose is considered one of the most destructive diseases for sour cherry production due to the rapid development of the disease on fruits. Glomerella cingulata (Stoneman) Spauld. & H. Schrenk (anam.: Colletotrichum gloeosporioides (Penz.) Penz. & Sacc. in Penz.) has been the fungal pathogen responsible for anthracnose in last decades. Yield losses greater than 90% may occur under epidemic conditions. C. acutatum (J.H. Simmonds, 1968) strains were isolated of sourcherry plantations in East Hungary and this pathogen, new for Hungarian microbiont became recently dominant. Contrarily to the former species it is certainly transmitted with ants during fruit ripening. About third of strains proved to be cutinase producers that enable them to actively penetrate via cuticule, and these strains infect directly berries of blackberry, grape and tomato as well as plum and apple. Most of cutinase negative strains could also infect these fruits after mechanic injury. All strains of both species produce amylase, cellulase, lecithinase, lipase, polyfenoloxydase and protease in vitro, although the activity of these enzymes highly varied in the medium. The only C. acutatum strains produced noticeable amount of chitinase. Strains, tolerant to recently applied fungicides to control the anthracnose, could be isolated of sour cherry plantations that might be the cause of ineffectiveness of control measures in 2010. The mycofungicide containing mixture of three Trichoderma species in oil carrier could efficiently depress the development of anthracnose in ripening sour cherry.
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Nutrient Uptake of Miscanthus in vitro Cultures
23-24Views:78The large biomass production and the low necessary input fertilizer make Miscanthus an interesting, potential non-food crop with broad applications, e.g. for fuel and energy, for thatching, fiber production, for the paper and car industries, as well as for ethanol production.
Axillary buds of Miscanthus x giganteus were placed on a shoot inducing nutrient solution (modified Murashige and Skoog, 1962), basic medium supplemented with 0,3 mg l-1 6-Benzylaminopurin. After 40 days of culturing, the axillary buds produced three times more shoots than could normally be harvested. The nutrient content (N, P, K, Ca, Mg) was measured several times during culturing. The results showed that, after 35 days, nitrogen and phosphate were nearly completely taken up. From that time, shoot growth was not observed.
After shoot propagation, the plants were transfered into a nutrient solution for root formation (modified Murashige and Skoog, 1962), basic medium supplemented with 0,5 mg l-1 Indole- 3-Butyric acid, and could be potted in soil after about 14 days. -
Effect of arginine, putrescine and spermidine on the polyamine, proline and chlorophyll content of tobacco (Nicotiana tabacum L.)
39-43Views:133Polyamines, such as spermidine (Spd) spermine (Spm) and their direct precursor, the diamine putrescine (Put) are vital and essential aliphatic amines which are also present in plants. Although ethylene and polyamines are also involved in fruit ripening, the genes coding them must also take part in other biosynthetic pathways. In the ethylene and polyamines play an important role in development of salt stress tolerance, and in responses for biotic and abiotic stresses. Exogenous application of all three main polyamines (Put, Spd, Spm) increase salt tolerance of plants, but, accordingly to previous experiments, spermidine has the main effect on the enhancement of salt tolerance. Nicotiana tabacum L. plants were grown in vitro on MS medium, the treatments were as follows: arginine (150 mg l-1), putrescine (10 mg l-1), spermidine (10
mg l-1). Proline, chlorophyll a, b and polyamine contents were measured. The obtained results show that the arginine decarboxylase and the spermidine synthase genes involved in polyamine metabolism, cannot be enhanced by exogenous addition of their precursor molecules. On the contrary, the spermine synthase gene has a positive effect to the lower-class forms of polyamines. -
Increase of Wheat (Triticum aestivum L.) Resistance to Leaf Rust (Puccinia tritici) via Gene Transformation
127-129Views:72Leaf rust is one of the most significant fungal disease of wheat not only in Hungary but also in other parts of the world. For improving leaf rust resistance of winter wheat variety (Hajdúság, 2003) produced by conventional breeding methods, verified by results of variety tests, showing outstanding results in the aspect of the most important economic values, integration of tissue culture technics, genetic engineering and traditional
methods may provide facilities. Building the gene(s) responsible for resistance into the determined genome can improve the resistance in a way that changes other features of the plant slightly or not at all. In the course of genetical transformation of the variety Hajdúság we applied one of the wheat’s own effecient green-tissue specific insurer genetical regulator, the promoter of ribulose carboxylase 1-5 bisphosphate (RuBisCo) ‘s small
subunit to control the expression of the gene cmg1. -
Effect of Selenium Supplementation on in vitro Radish and Green Pepper Seedlings Germination
149-155Views:167Selenium (Se) is an essential trace element for animals, microorganisms and some other eukaryotes. It has become increasingly evident that Se plays a significant role in reducing the incidence of lung, colorectal and prostate cancer in humans. Although there is evidence that selenium is needed for the growth of algae, the question of essentiality of Se in vascular plants is unresolved. Therefore Raphanus sativus (Se accumulator) and Capsicum annuum (non Se accumulator) were treated with 0-200 mg/l natrium-selenate. The results showed that lower (2 mg/l) concentration natrium-selenate increased the fitomass and total antioxodant capacity in seedlings.
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Testing the antimicrobial activity of essential oils
71-74Views:140The vapor phase of some essential oils proved to have antimicrobial activity. Utilization of the vapor phase of Eos is presently understood as one of the possible alternatives to synthetic food preservatives which could be used in the future. However, testing the vapor phase of EOs against microorganisms causing food-borne diseases (e.g. Salmonella enteritidis or Staphylococcus aureus) or food spoilage is relatively new. Consequently, due to the large number of known EOs, research on their antimicrobial activity is still largely in the phase of in vitro rather than in vivo testing. Moreover, no standard and reliable method for fast screening of a wide range of samples exists. Thus, the aim of this study is to show results concerning tests of the antimicrobial activity of EOs against S. enteritidis or S. aureus, which were conducted by two modifications of the disc volatilization method we developed. The lately developed method has the potential to become widely used for fast screening of EO antimicrobial activity in the vapor phase.
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The recent state of cryopreservation techniques for ex-situ gene conservation and breeding purposes in small ruminants: A review
81-87Views:290The viewpoint of the recent cryopreservation techniques (CT) suggests the use of a reduced volume of cryopreservation solution, high concentration of cryoprotectants and ultra-rapid cooling and warming rates help to reduce cryo-injury and maximize the viability of the preserved animal genetic resources (AnGR). The CT had now become widely accepted as one of the best methods of choice for the ex-situ conservation of AnGR due to its high success rate recorded and no-invasive nature as compared to the conventional slow rate freezing (CSRF). Rapid advances and wide acceptability of the use of assisted reproductive technologies (ART’s) particularly artificial insemination (AI) in animal breeding had resulted in a greater loss of a large number of good quality genes in virtually almost all the native breeds of animals across the globe. Small ruminant (SR) animals are not an exception in such present predicaments situation of erosion and dilution of the valuable AnGR among the native breeds. As a result of this, 148 and 16 breeds of sheep and goats respectively have already become extinct in Europe and the Caucasus. In view of the aforementioned situation, the present review aimed at exploring some of the current states of development, roles played and potentials of CT in the conservation of SR genes and genome for the immediate and future breeding purposes for sustainable development. It basically covers; animal genetic resource, the need to conserve AnGR, tools for ex situ in vitro conservation of AnGR and recent developments in breeding and cryopreservation of SR AnGR.
Cryopreservation is playing a pivotal role in ex-situ gene conservation of AnGR. Decline in genetic diversity among SR breed population was high in Europe and the Caucasus. There is therefore, need for improvent on current stringent measures on conservation of AnGR in this region of the world.
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Azoxystrobin resistance of Botrytis cinerea Pers.:Fr. isolates
56-63Views:98Fungicide resistance is one of the most important problems endangering the effectivity of practical plant protection today. The frequent and subsequent usage of specific fungicides results the emergence of resistant fungal populations. This threatens is especially high in case of Botrytis cinerea Pers.:Fr. being an endemic pathogen with frequent infection. Nowadays the main method of protection as against Botrytis cinerea is the application of chemical fungicides chemicals. Therefore, a better knowledge of local populations is necessary for the planning of the protection procedures.
Based on the results of our examinations we may establish that the growth of the examined samples showed a significant difference under in vitro circumstances, which shows a great deal of variability of the Botrytis cinerea populations in Hungary. Twenty-five Botrytis cinerea samples from different hosts were analyzed in this study. High resistance was found towards azoxistrobin in seven cases, and low resistance in eight cases.
It was also proved, that the B. cinerea is able to bypass the inhibition site of the azoxistrobin via the alternative oxidase. The presence of this altermative mitocondrial electrotransport route considerably reduces the effectivity of the chemical. -
Investigation of host-specificity of phytopathogenic fungi isolated from woody plants
155-160Views:149Host-specificity is an important characteristic of fungal pathogens. Changing climate could create more appropriate environmental conditions for phytopathogens, thus formerly host-specify fungi could be able to colonize new hosts. Noxious plant pathogen fungi, which can infect several plant species are well-known worldwide. These genera may expand their range of hosts because of the appearance in new geographic areas due to climate change. This new exposure can result in serious problems in agriculture because of the lack of immunity. The susceptibility of apple tree was studied through testing pathogenicity in vitro with species isolated from walnut twigs and nuts, and identified by ITS sequences. Three of four tested species, Botryosphaeria dothidea, Diaporthe eres and Diplodia seriata colonized and necrotized the infected apple branches, while Juglanconis juglandina was not able to infect the twigs. Members of Botryosphaeriaceae were the most virulent, causing the largest lesions in the fastest way. This experiment draws attention to the threat of new host-pathogen connections, which can arise because of the favourable weather conditions and can spread between neighbouring cultures.
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Qualitative detection of genetically modified organisms in plant samples
309-313Views:124We analysed the GMO content of corn samples by polymerase chain reaction following the appropriate optimization of the reaction. The analysis included two main steps: extraction of DNA from the sample, and detection of the GMO content by polymerase chain reaction. The polymerase chain reaction is an in vitro method to multiply chromosomatic or cloned DNA (cDNA) sequences through the enzymatic pathway. The reaction is sensitive enough to produce DNA in sufficient amount for the analysis from a single DNA. We identified the PCR products by agarose gel electrophoresis. When optimizing the reaction, the MgCl2 concentration, reaction time and temperature have to be taken into consideration. The temperature of the anellation has to be increased until the highest specificity and yield is reached. If the temperature of the anellation is too high, the primer is linked to non-specific sites as well; in the gel visualization, more lines can be seen at one sample. If the temperature of the anellation is too high, the primer is insufficiently linked or is not linked at all (too few lines in the gel visualization). After optimization, the GMO content in the unknown sample can be determined along with the appropriate positive and negative controls.
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Vitrification of mouse embryos by vitroloop technique
81-83Views:103The objective of the study was to vitrify mouse embryos with the cryoloop technology using a new combination of vitrification mediums. Embryos were exposed to a 2- step loading of CPA, ethylene glycol and propylene glycol, before being placed on the surface of a thin filmy layer formed from the vitrification solution in a small nylon loop. After warming, the CPA was diluted out from the embryos by a 3-step procedure. Our data show that a high percentage of embryos survived (92.7%) vitrification in the mixture of EG and PG combined with cryoloop carrier and developing normally (89.1%) in vitro after thawing.