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The role of disease resistance in the registration of crop varieties in Hungary
27-29Views:206Variety testing including disease resistance test of the major crops has been carrying out since the 1960’s in Hungary. Testing for resistance of the new candidate varieties is performed in the so-called VCU (Value for Cultivation and Use) trials under natural infection and in special small-plot or micro-plot trials using different disease provocative methods. Disease resistance, especially those of multiple and horizontal-type (race non-specific, partial or durable) resistances, has recently become a key limiting factor in the state variety registration. The role of disease resistance in the decision-making process of variety registration is demonstrated on the examples of winter wheat and sunflower as two major field crops in Hungary.
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Increase of Wheat (Triticum aestivum L.) Resistance to Leaf Rust (Puccinia tritici) via Gene Transformation
127-129Views:147Leaf 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. -
Fruit melanotic ringspot (FMRS) – a disease of resistant Capsicum genotypes infected with Tomato spotted wilt virus (TSWV) on the fruits
64-69Views:145Etiology of pepper fruit melanotic ringspot (FMRS) disease (Salamon, 2009) was studied on fruit samples collected in forced pepper populations. It was noticed that in spite of heavy thrips (Frankliniella occidentalis) infestations and of TSWV epidemy detected in the forcing houses, FMRS occurred only in plants having healthy foliage. Symptomatological surveys strongly suggested that FMRS appeared exclusively in specific pepper genotypes. The size of melanotic ringspots has been observed to grow at room temperature during postripening of diseased fruits. A mechanically transmitted plant virus was isolated from symptomatic parts of 9 white pepper fruits affected by FMRS. On test plants each of the virus isolates caused systemic symptoms characteristic to TSWV. Using cDNA/PCR technique and TSWV N-gene specific primers a ca. 300 bp long DNA fragment has been amplified from total nucleic acid extracted from symptomatic tissues but never from asymptomatic parts of the fruits showing FMRS. Plant progenies grown from seeds of FMRS diseased fruits segregated in respect of resistance and/or susceptibility to TSWV infection. TSWV was also detected in and isolated from three fruits showed non-melanotic yellow rings (one of them was infected with a tobamovirus, too). Seedlings derived from these fruits proved to be susceptible to TSWV. Based on the above results we could conclude that the FMRS disease developed on fruits of “cecei” type white peppers that carry a TSWV resistance gene, most likely the Tsw gene in heterozygous form. These fruits were infected with thrips transmitted TSWV and FRMS appeared as a hypersentive reaction (HR) manifested in fruits.
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Susceptibility of maize hybrids to corn smut diseas
39-42Views:336Corn smut disease is one of the most common maize diseases. In the previous years the disease lost from its importance, however nowadays it is becoming more and more important and widespread. The protection against it encounters great difficulties, therefore it is important to emphasize prevention and resistance based protection. The aim of the research was to investigate under laboratory circumstances the resistance of Hungary’s most commonly cultivated maize hybrids to corn smut disease. Twelve species were investigated. We distinguished two susceptibility groups within the hybrids based on the investigated parameters. The results are intended to assist the protection against corn smut disease and to make a suggestion for the farmers so that they could apply more environmental friendly and economical production.
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Examination of resistance against Aeromonas hydrophila infection on genetically different common carp variants (preliminary results)
7-11Views:181Septicemia disease caused by the bacterium Aeromonas hydrophila is a major problem for fish farmers around the world. In our experiment resistance to the disease was investigated on carp variants with diferent genetical backgrounds. 96 different genetic variants(„families”) were created by crossing various individuals of 4 carp strains (2 wild and 2 cultured ones). Families were reared until reaching the size of 10 gramms and 100 fish of each families were marked with an individual electronic identifier. Marked fish were divided into 5 groups. Fish from one group were infected with A. hydrophila and mortality were registered during 2 weeks. Based on mortality data, the most resistant and most susceptible families will be selected using population genetics methods.
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Testing disease resistance in autumn wheat genotypes by means of field experiments
30-40Views:280According to our scientific results we can state that we have to use integrated pesticides management in crop protection against the diseases of winter wheat. One of the most important elements of IPM is to select a genotype characterised by good resistance to diseases (and by high yield ability and excellent baking quality). It is especially important that the wheat variety have tolerance against not only to one or two leaf and spike (grain) diseases, but „complex” tolerance. It is not necessary to give up the growing of a variety which has susceptibility to different diseases because we can protect it using appropriate chemical management. In the intensive growing stage of wheat (BBCH 32-37) we can use a noncompulsary fungicide-treatment (depending on e. g. the infection, ecological conditions) and, at the beginning of the flowering stage
(BBCH 59-65), we have to use a compulsary fungicide-treatment (in spite of e. g. special weather conditions, resistance genotype)to ensure high yield and good quality. -
Cytochrome b diversity of Hungarian Botrytis cinerea strains
18-21Views:221In the mitochondrion of eukaryotes, cytochrome b is a component of respiratory chain complex III. Cytochrome b is encoded by the
cytochrome b (CYTB) gene located in the mitochondrial genome. The fungicidal activity of QoIs relies on their ability to inhibit mitochondrial respiration by binding at the so-called Qo site (the outer quinol-oxidation site) of the complex III. Since their introduction, QoIs (like azoxystrobin) have become essential components of plant disease control programs because of their wide-ranging efficacy against many agriculturally important fungal diseases like grey mould on various crops. QoI resistance primarily arises from a target-site-based mechanism involving mutations in the mitochondrial CYTB. As the management of grey mould is often dependent on chemicals, the rational design of control programs requires the information about the diversity of genes connected with resistance in field populations of the pathogen.
Monospore B. cinerea field isolates has been collected during 2008-2009 from different hosts in Hungary. PCR fragment length analysis
indicated the high frequency presence of type large intron in the isolates while in a few strains G143A substitution could also be detected.
These results indicated the heterogeneity of CYTB in the Hungarian B. cinerea populations, which possibly involve the heteroplasmy of this
mitochondrial gene, moreover indicates the existence op azoxystrobin resistant populations in Hungary.
This work was supported by NKFP-A2-2006/0017 grant. Erzsébet Fekete is a grantee of the János Bolyai Scholarship (BO/00519/09/8). -
Sensitivity of maize hybrids to common smut under field artificial inoculation conditions
25-28Views:476Common smut disease of maize is one of the most frequent diseases of crop. In the last decades the importance of disease has decreased in feeding maize production, however its importance increasing again nowadays, especially at sweet maize hybrids. The aims of this work was to find hybrids possess of resistance, and to evaluate which ones are more or less susceptible under field artificial inoculation circumstances. Among feeding maizes the less susceptible hybrid was ‘P9578’, and the most susceptible ’NK Columbia’ hybrid, and differences in cob infection between them was significant (8.8%). At sweet corn hybrids the less susceptible was ’Prelude’, while the most susceptible was ’Jumbo’ with very high significant 74.6% differences.
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Studies on the Fusarium stalk rot infection of the maize genotypes using the Findex percentage and a computerised image analysis program
45-51Views:211In a continental climate, the pathogens causing the most serious problems are species belonging to the Fusarium genus. When the pathogen attacks the stalk, the plant dies earlier, reducing grain filling and resulting in small, light ears. In addition, the stalks break or lodge, resulting in further yield losses from ears that cannot be harvested. During the three years of the experiment, 14 inbred lines were examined. The genotypes were sown in a two-factor split-plot design with four replications, with the genotypes in the main plots and four treatments in the subplots: two Fusarium graminearum isolates (1. FG36, 2. FGH4), 3. sterile kernels, 4. untreated control. The results experiments showed significant differences between the genotypes for resistance to fusarium stalk rot. Among the inbred lines the best resistance to fusarium stalk rot was exhibited by P06 and P07, both of which were related to ISSS. The precision and sensitivity of disease evaluations carried out visually and using image analysis software were compared in the experiment, and with two exceptions the CV values were lower for the image analysis. As the CV for measurements can be considered as a relative error, it can be stated that image analysis is the more precise of the two methods, so this technique gives a more accurate picture of the extent of stalk rot. The extent of stalk rot developing in response to natural infection is extremely environment-dependent, so the use of artificial inoculation is recommended for selection trials.
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The Effect of Forecrop and Plant Protection on the Pathology Parameters and Yields of Winter Wheat
84-89Views:265We carried out our experiment in the cropyears of 2000/2001, 2001/2002 and 2002/2003, on calcareous chernozem soil, at the experimental site of the Debrecen University Farm and Regional Research Institute, at Látókép. We examined the disease resistance and the yield quantity of Mv Magvas variety by adopting different forecrops and plant protection technologies, at 30+30 N level and at normal cereal row spacing. We applied two forecrops (wheat and pea) and two plant protection technologies (extensive and intensive). We measured the rate of infection by population survey in the first ten days of June.
In the course of our examinations, we found, that the rate of powdery mildew infection was higher in the thicker population sown after pea forecrop in all three years, as powdery mildew is not a typical cereal disease.
The infection rate of leaf mildew and DTR (Dreschlera tritici-repentis) was higher after wheat forecrop in all examined years, because these are typical wheat diseases and infection centres in the soil promote the spreading of these diseases. However, it was possible to parry the adverse effect of forecrops by intensive plant protection.
Due to the chernozem soil, wich has good water management features, and due to the good preparation of the seedbed, the effect of forecrops on yield quantity did not appear in the examined years. The quantity of the yield was only slightly larger after pea forecrop in the cropyears of 2000/2001 and 2002/2003 than after wheat. Nonetheless, the data of technical literatures state that the yield quantity can be larger, even by 15-20%, after pea forecrop.
In the course of intensive plant protection technology, we applied systemic pesticides, while in the course of environmentally sound technology, we used contact pesticides of sulphur content. In those populations that were treated with environmentally sound plant protection technology, infection rate was higher in all three years.
Yield quantities were somewhat lower in the course of applying extensive, environmentally sound technology, because diseases appeared in these populations to the higher degree. Powdery mildew does not, but leaf mildew and Dreschlera tritici-repentis have a significant yield decreasing effect. With appropriate, well-selected fungicides, we were able to keep every leaf diseases well in hand, and the rate of infection was almost independent of the influence of the breeding year. -
The examination of the agronomy, the amount of yield, and the yield stability of winter wheat varieties
61-72Views:208Our research was carried out at University of Debrecen Centre for Agricultural Sciences Faculty of Agriculture Institution of Plant Sciences Látókép Research Institute through the breeding year of 2003/2004, 2004/2005 and 2005/2006 using cherrnozem soil. In our research we tested 14 chosen autumn wheat varieties during the three crop years.
The different varieties showed very dissimilar ability of resistance against diseases through the three crop years. We could observe both susceptible and resistant varieties. Susceptible varieties got diseases even in favourable crop years. The observed winter wheat varieties showed higher susceptibility against helminthosporium (21.8%) and leaf rost (16.4%). Among the 14 varieties we experienced the least susceptibility in the case of ‘Gaspard’ and ‘GK Kalász’. The research showed that the disease of fusarium undoubtedly depends on the features of the crop year.
In terms of stem solidity we experienced big differences. Among all the observed winter wheat varieties the mid-late ripening ‘Gaspard’ showed the best results in the average of the three years, only 5.3% was beaten down.
The three ripening group of the winter wheat showed the following average yield in the average of three years: 7065 kg/hectare (early ripening varieties), 7261 kg/hectare (late ripening varieties), 6793 kg/hectare (mid-late ripening varieties). Among all the observed varieties the early ripening ‘Flori 2’ produced the biggest yield (7692 kg/hectare).
During the three crop years we reached very different amounts of yield which means that weather conditions had a telling affect on yield. In 2004 we reached an excellent average yield in all the tree breeding groups because of the favourable weather conditions. In 2005 we had a moderate amount of yield because of the unfavourable weather conditions of winter. The year of 2006 showed the smallest amount of yield which is due to the fact that the plant grew less thick than usually.
There were significant differences among the observed varieties in the term of yield, which can be attributed to dissimilar biological basics.
One of he most important questions is the yield stability of the varieties. We had extremely different results at this field. Speaking in general terms we can state that both weather conditions and genetical abilities have a determining effect on yield. In the case of winter wheat varieties the rate of yield fluctuation was quite big, moving in the interval of 33.7-70.3%. Among all the observed varieties ‘Gaspard’ showed the best yield stability (33.3%). -
Current Conditions and Opportunities of Biofarming in Hungary
150-156Views:201The aim of organic farming is not to maximize income, but to achieve optimal product quality. It is completed by the tightest possible material, and energy flow within the farm. Organic agriculture significantly reduces external inputs by avoiding the use of chemo-synthetic fertilizers, pesticides and pharmaceuticals. Instead it works with nature to increase both agricultural yields and disease resistance. Total independence of external resources can not be achieved in Hungary due to the small-scale of organic animal husbandry. Some materials in limited quantities can be purchased from external resources, though the group of these materials is strictly regulated. Organic farming harmonizes with the concept of European multifunctional agriculture, because besides farming, it includes social considerations, as it helps to maintain natural resources and the relationship between people and their environment, and provides a living for those living in the region.
As regards organic farming the fertility of the soil and the health of vegetation can be influenced in various ways. Farmers have to be highly skilled and able to manage a farm with great expertise. Generally it can be stated that as the use of non-organically produced products is limited, the opportunities to correct failures made by the farmer are minimal, contrary to conventional farming. Farmers must be intent on developing the tightest material- and energy flow. This means that organic farms ideally have both animal husbandry and crop production. This energy and skill demanding system of farming is compensated by state subsidies, growing market share and relatively high prices for organic products. -
Impact of nitrogen and sulphur fertilization on the growth and micronutrient content of spring wheat (Triticum aestivum L.)
211-219Views:327Micronutrients are as important as macronutrients for crops. Each micronutrient has its own function in plant growth. Zinc is important for membrane integrity and phytochrome activities. Copper is an essential micronutrient required for the growth of wheat. Manganese is required for enzyme activation, in electron transport, and in disease resistance. The pot experiment was set up in greenhouse on calcareous chernozem soil Debrecen-Látókép with a spring wheat. In certain development stages (according to BBCH growth scale of wheat), at the beginning of stem elongation (29–30), at the heading (51–59), at the flowering (61–69) stage three average plants were removed from all pots for analysis. Fresh and dry weight of the plant samples were measured. Plant leaves after drying were digested by HNO3-H2O2 methods and manganese, zinc and copper contents of plant were quantified by atomic absorption spectrophotometry. At the flowering stage, when the nutrient uptake of plants is the most intensive, the weight of wheat ranged between 0.94–1.57 g plant-1. In this development stage, the NS2 treatment produced the highest weight of wheat, and compared to this the NS3 treatment decreased that value already. The results show unfavourable effect of NS3 treatment. On the basis of microelement content of wheat and the weight of a plant, nutrient uptake by plant were calculated. At the beginning of growth the starter treatment had positive effect on Cu-uptake compared to the NS1 treatment, where the same dose of fertilizer was stirred into the soil. Wheat is very sensitive to copper deficiency, so copper dissolved by starter treatment could be favourable to the early development of wheat. At flowering stage the Zn-uptake of wheat became the highest and it was between 133.7–234.6 mg plant-1. The Mn-uptake of wheat plant was higher than the Cu- and Zn-uptake of wheat.
This phenomenon can be explained by the fact that the untreated soil had higher Mn-content, than Cu- and Zn-content. To summarize the results, it can be stated, that the copper uptake of wheat was more affected by the different treatments in the stage of stem elongation, while Mn- and Zn-uptake of wheat were influenced primarily in the stage of heading and flowering.
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Advancement of a Common Wheat (Triticum aestivum L.) Selection System
8-11Views:167All the research in Hungary and other countries in Europe focus on improving the quality of crops and increasing the competitiveness of production.
In this respect, we have to advance the conventional technological elements, reduce the application of pesticides and fertilizers, and produce new varieties suitable for environmentally-sound production. In our crop breeding programs, we applied conventional and biotechnological methods (embryo rescue and double haploid methods) in order to get somaclonal and gametoclonal variations.
We produced winter wheat lines (HP-31-95, HP-82-96) by traditional way, which have high baking qualities and high nutrient efficiency. Some diseases can limit the quantity and quality of a wheat crop. We examined several wheat diseases in our winter wheat candidates, and we found that our progenies have resistance to leaf rust.
With respect to a serious problem was the small quantity of applied fertilizers and the other externals, our research focused onto advance a common wheat selection system, with the help of it, we can handle these problems. We have summarized that our selected progenies can compete with the registered varieties with quality and environmental respect. -
Susceptibility of stem infected sweet corn hybrids to common smut disease
55-57Views:795The common smut of maize (corn smut, Ustilago maydis /DC/ Corda) can cause large economic losses in susceptible sweet corn hybrids as well. The protection against this pathogen is fundamentally based on prevention. Many methods to control corn smut have been recommended or evaluated, including crop rotation, sanitation, seed treatments, modification of fertility, and biological control. In spite of these frequently mentioned control strategies, the host resistance seems to be the only effective method to manage common smut in those areas where Ustilago maydis is prevalent.
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The potential use of Pediococcus spp. probiotic in aquaculture: A review
99-106Views:475Aquaculture production has significantly increased over the previous few decades. However, antibiotics have been implemented regularly and extensively to overcome outbreaks of pathogens in aquaculture to cover the human needs for animal protein, leading to the appearance of resistant strains that may cause serious damages in the environment and also human health. In the last few years, the implementation of probiotics as an alternative technique to antibiotics use in fish production has achieved promising results in aquaculture due to their beneficial impact on fish health and growth performance. Among different types of probiotics, the Pediococcus spp. bacteria stand out as a promising probiotic for their beneficial impact to aquaculture. Thus, the current study has been conducted to give an overview about the interactions between Pediococcus spp. and aquaculture. In addition, this review highlights the role of Pediococcus spp in promoting growth performance, improving feed conversion ratios and the intestinal architecture, enhancing the immune response and inhibiting fish pathogens, thereby preventing or at least reducing the use of antibiotics. Practical use of Pediococcus spp. probiotic in aquaculture as feed additives through selected case studies is also considered.
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Seed biology and possibility of improvement of seed germination capacity on Virginia mallow (Sida hermaphrodita L. Rusby)
71-76Views:238Sida hermephrodita or Virginia mallow is a perspective perennial herb in the Malvaceae family able to yield a biomass crop through the last two decades. Additionally, the plants have a lot of uses and benefits for instance it can use as a fodder crop, honey crop, ornamental plant in public gardens. It has favourable features like fast growing and resistance against the disease and climatic fluctuations, etc. Sida is in the beginning phase of domestication therefore it has a serious disadvantage: the low and slow germination as a big part of wild plants. Due to the expressly low germination percent the need of seed showing of driller is should tenfold, 200 thousand seeds/acre instead of 10–20 thousand what is not available and expensive Therefore practical purposes of our research of seed physiology was to increase the seed germination percent in a available, basically wild Sida population. In the first stage of our experiments we examined two factors relating to seed germination percent and seed germination power during our research: the influence of hot water treatment and the effect of exogenous or endogenous infection of seed. However, in our germination tests, utilizing scarified seeds with hot water (65 oC, 80 oC, 90 oC), from 29,3% to 46% germinated from those samples which were collected from the population of Sida hermaphrodita in Debrecen. The average germination for all season was 5–10% without treatment and rinsed using hot water up to almost 50%. When physically scarified used, the oldest seeds showed the best germination (46%) after the hot water operation in spite of the previous studies. We discovered that apparently there are close relationship between the seed fresh weight or water uptake capability and the percentage of infection. Following these recognition we modified our technique,in such a way that we fractionated the seeds based on their fresh weight/or relative density before we carried out the treatment. When we filtered the floating seeds on the surface of water, the hot water treatment was performed considerably better on the sunk seeds after separation. Therefore, by this special priming process we were able to reach 80% germination capacity of Virgina mallow seeds under laboratory conditions (26 oC without illumination).
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The Carpathian lingonberry, raspberry and blackberry fruit extracts feature variable antimicrobial efficiency
27-32Views:493Wild berry is an excellent source of phytonutrients and/or bioactive compounds associated with significant therapeutic properties, so that they have been utilized in folk medicine and traditional nutrition throughout centuries. Multiple health-promoting effects, such as anti-inflammatory, anti-diabetic, anti-heart and coronary disease properties were attributed to such wild berries. It has also been proved that berries could feature antimicrobial effects that could be of a great importance for the prevention of food-feed poisoning and fighting back antibiotic resistance.
In this study, we investigated the antimicrobial properties of lingonberry (Vaccinium vitis-idaea), raspberry (Rubus idaeus) and blackberry (Rubus fruticosus) crude and ethanolic extracts prepared from fruits obtained from the spontaneous flora of Eastern Carpathian Mountains situated in Transylvania. The antimicrobial effect of crude and alcoholic extracts were assessed on four Gram-negative, five Gram-positive bacteria and one yeast species using the agar diffusion method. The studied bacteria can cause food or feed spoilage and foodborne diseases. Our results indicate the significant inhibitory effect of lingonberry extracts in the case of Gram-negative bacteria like Proteus vulgaris and Salmonella Hartford, while among Gram-positive bacteria the strongest inhibitory effect was observed for Bacillus species like B. cereus, B. subtilis, B. mojavensis and Micrococcus luteus. The raspberry and blackberry extracts featured milder inhibitory effects in the case of the studied bacteria species. Furthermore, we have studied the crude or ethanolic extract combinations associated antimicrobial effects synergistic/additive or antagonistic properties. Interestingly, the triple and double ethanolic extract mixes had stronger antimicrobial properties, whereas the crude extract mixes showed relatively reduced effects, if any. Our results indicate that the antimicrobial activity of studied fruit extracts obtained from wild berries can vary upon the applied extraction method and their combination formulae, so that all these considerations must be taken into account when such fruit extracts are considered for foodstuff development.
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Effect of fish feed containing two Chinese herbal extracts (Ganodema Iucidum and Lonicera japonica) on the non-specific immune system of Nile tilapia, Oreochromis niloticus (preliminary results)
9-14Views:200The effect of two Chinese herbs (Ganoderma lucidum and Lonicera japonica) on non-specific immune response of tilapia was examined. In addition to the control (no herbs), three diet variations were used. These contained 1.0% of Lonicera, 1.0% of Ganoderma and a mixture of Ganoderma (0.5%) and Lonicera (0.5%). The respiratory burst and phagocytic activity of blood leukocytes were monitored. Three weeks after feeding, the fish were infected with Aeromonas hydrophila. The results of this study showed that feeding tilapia with Ganoderma and Lonicera alone or in combination enhanced the phagocytosis of blood leukocytes, but not the respiratory burst activity. Both herbs, when used alone or in combination, reduced mortality after challenge with A. hydrophila. The highest mortality was observed in the control fish – 56.66%, and fish fed with Lonicera extract – 43.33% while 30% of fish died in the group fed with Ganoderma and the lowest mortality (20%) was observed when the fish were fed with a combination of the two herbs. It can be concluded that the herb extracts added to this diet act as immuno-stimulants and appear to improve the immune response and disease resistance of tilapia.