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Examination of nutrient leaching dynamics of Solidago virgaurea in Hévíz Lake and Hévíz canal
207-211Views:255The different nitrogen and phosphorus elements are prime constituents of the ecosystem and can exert a major effect on aquatic species and the overall ecological cycle. During our investigation we examined the nutrient leaching dynamics in decomposing leaf litter (stem and leaf blades) of Solidago virgaurea. We chose four different sampling sites during the winter period with different water temperatures in the Hévíz Lake and Hévíz canal. The bottles containing the plant material and water were incubated at natural temperatures and the fluid was removed at particular times. Water parameters such as pH level, conductivity, nutrients (ammonium and phosphates) were measured. In the case of Solidago leaf, we obtained higher values for all parameters compared to the stem ones.
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Analysis of the Environmental Status of Nagykálló Subregion
362-367Views:189The third smallest region of Szabolcs-Szatmár-Bereg county is the Nagykálló subregion. Its territory is 377 km2 and its inhabitants number 32.526. Due to the fact that industrial development arrived late, the environmental status of this subregion was saved from serious ecological degradation. The quality of the environment shows a reasonable picture in many respects, comparing to the general survey of the country. The air quality of the region can be qualified as acceptable. Leaving some critical points out of consideration, it is better than the national average. It is favourable from the human environment point of view that the region is free of extremes, and has a balanced climate. The supply of drinking water is above 95%, and the remainsing water requirements are supplied by artesian wells. The water supply network is fully extended in the subregion. The most significant environmental noise source is traffic, including public road traffic, which causes a problem in the town of Nagykálló. The situation of the collection, transportation, and placement of the settlement’s solid wastes show a similar picture to the status of the country. The environmental status of the region is included in the SWOT analysis.
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Interpretation of the multifunctional agriculture’s function in regional dimensions
177-181Views:211Many branches of science have been examining the concept of multifunctional agriculture. Different interpretations have come into being on global and regional dimensions as well. This study deals with certain interpretations of the concept of multifunctional agriculture. It compares the concepts about multifunctional agriculture of the United States, the Cairns-group, the least developed countries (the LDC-s), as well as the developed countries which import food (the G10), the concept of the EU and Hungary too. It states that the different approaches to the concept have been started by the agricultural problems which are typical of certain areas. These problems have been formed in each and every area by the threefold functions (economic, social and ecological), which are characteristics of rural areas.
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Possibilities for Growing Fennel in Hungary
119-121Views:173Fennel appers to be cupable of enlarging our vegetable sortiments in Hungary. Ecological conditions favour production. For cultivation, 12,5 plants/m2 are recommended. Fennel requires 250-300 mm water over a 110 day growing period. No considerable pests have been found yet. 1-3 kg/m2 tubers can be harvested. Marketable tubers weigh 200-300 g. Smaller tubers can be dried, pickled or deep frozen.
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Comparative analysis on the fertiliser responses of Martonvásár maize hybrids in long-term experiments
111-117Views:233The results of experiments carried out in the Agricultural Research Institute of the Hungarian Academy of Sciences clearly show that in the case of hybrids grown in a monoculture greater fertiliser responses can be achieved with increasing rates of N fertiliser than in crop rotations. In the monoculture experiment the parameters investigated reached their maximum values at a rate of 240 kg/ha N fertiliser, with the exception of 1000-kernel mass and starch content. In both cases the starch content was highest in the untreated control, gradually declining as the N rates increased. Among the parameters recorded in the crop rotation, the values of the dry grain yield, the 1000-kernel mass, the protein yield and the starch yield were greatest at the 160 kg/ha N fertiliser rate, exhibiting a decrease at 240 kg/ha. Maximum values for the protein content and SPAD index were recorded at the highest N rate. It is important to note, however, that although the N treatments caused significant differences compared to the untreated control, the differences between the N treatments were not significant.
In the given experimental year the values achieved for the untreated control in the crop rotation could only be achieved in the monoculture experiment at a fertiliser rate of 160 kg/ha N, indicating that N fertiliser rates could be reduced using a satisfactory crop sequence, which could be beneficial from the point of view of environmental pollution, crop protection and cost reduction.
The weather in 2006 was favourable for maize production, allowing comparative analysis to be made of the genetically determined traits of the hybrids. Among the three hybrids grown in the monoculture experiment, Maraton produced the best yield, giving maximum values of the parameters tested at a fertiliser rate of 240 kg/ha N. The poorest results were recorded for Mv 277, which could be attributed to the fact that the hybrid belongs to the FAO 200 maturity group, while the other hybrids had higher FAO numbers. Maraton also gave the highest yields in the crop rotation experiment at the 160 kg/ha N level. All three hybrids were found to make excellent use of the natural nutrient content of the soil.
It was proved that the protein content of maize hybrids can only be slightly improved by N fertilisation, as this trait is genetically coded, while the starch content depends to the greatest extent on the ecological factors experienced during the growing season. -
Using sensors in precision crop production
267-270Views:287Proper plant nutrition that takes into consideration both the requirements of plants and ecological conditions is one of the most important precondition of successful plant production. An important element of the N-fertilization of wheat is that the optimum zone of nitrogen supply is significantly narrower than that of other plant species, therefore it can easily happen that we apply higher or lower nitrogen doses than the optimal one. A possible solution to this problem can be precision agriculture. Applying the methods of precision agriculture we can take into consideration the heterogeneity of fields. By applying precision methods either online or offline we can intervene faster than if we would rely only on regular soil and plant analysis procedures. The determination of the doses of nitrogen and the timing of application are influenced also environmental and
economic aspects. The chlorophyll content of the leaves indicates the nitrogen status of plants, since there is a relationship between the nitrogen content and the amount of chlorophyll in the leaves. According to plant analysis results there was a strong and significant relationship between the values of the NDVI (Normalized Difference Vegetation Index)and the total nitrogen content measured in the leaves. -
Data on the bumblebee assemblages (Apidae: Bombus spp.) lives in lands under agri-environment commitment
31-35Views:483The goal of agri-environmental schemes (AES) and greening programs are protecting and increasing biodiversity in agricultural lands. The evaluation of effectiveness of AES needs further investigations. For the purpose of investigations, species and species groups should be selected which can indicate the effects of changes in landscape use on biodiversity. Bumblebees are good indicators for this purpose.
The role of bumblebees in pollination is well studied but in the case of different crops, much less detailed data are available. In 2018, bumblebee assemblages of 44 sites belonged to 8 different agricultural and semi-natural habitat types were studied in the surroundings of Sajószöged, Tiszaújváros and Derecske.
This study provides new distribution data of 8 bumblebee species in three 10×10 km UTM cells covering the sampling area. According to our results, the alfalfa and red clover fields and semi-natural grasslands has more species rich and abundant bumblebee assemblages than different crop fields (sunflower, oilseed radish and vegetable morrow) and can help protect bumblebee assemblages of agricultural lands. Based on the collected distribution and abundance data, the role of the bumblebees in pollination of the studied crops should be re-evaluated.
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Effect of year and irrigation on yield and quantity of different potato varieties
7-14Views:370dramatically in the last few decades. We are lagging behind Western European countries as regards yields. The ecological conditions are not favourable for potato, but the low yields other causes: the use of non-suitable seed, the low level of irrigation and nutrient supply and out of date machinery. The competitiveness of production is further decreased by the great alternation in yields from year to year, unpredictable market conditions, poor consumption habit, and often the lack of quality products.
The experiment was carried out at the experimental site of the University of Debrecen, Farm and Regional Research Institute, at Látókép. In our experiment, we examined the yield and selected quality parameters of 9 medium-early varieties in large parcels. Of the examined varieties, 3 are of Dutch, and 6 are of Hungarian breeding.
The experiment was set up in 2004 and 2005, on 50 m2 parcels on calcareous chernozem soil after winter wheat (2004) and two rowed barley (2005) as a forecrop. The varieties were examined in 4 repetitions in randomized blocks, of which two repetitions were irrigated, and two were non-irrigated. We examined the yields of the varieties, the distribution of tubers according to size and their percentages and changes, and selected parameters of quality and chemical composition due to irrigation. We studied the dry matter content, the starch content, the underwater mass, the amount of reducing sugars, and the colour index of frying of the tubers.
Summary, it can be stated that among the agrotechniques, year effect, variety and irrigation factors have considerable impact on potato yield quality and quantity. However, the impact of irrigation depends on the year effect. -
Phytocoenological researches on the grasslands of the middle and inferior basin of Crişul Negru river
41-45Views:265The meadowlands from the middle and inferior basin of Crisul Negru river form an area with rich flora and vegetation suitable for a complex phytocoenological research and an ecologic and bio-economical study of the floor vegetation.
After conducting a number of 80 phytocoenological surveys on the meadowlands near Apateu and Satu Nou villages (Arad county, Romania), respectively near Cociuba Mare and Mărțihaz villages (Bihor county, Romania) there have been identified a number of fifteen vegetal associations from which one is examined in this work.
The paper presents the hygrophilic association Typhetum latifoliae Lang 1973 on the grasslands of the middle and inferior basin of Crişul Negru river, association classified from the coenotaxonomic point of view in the alliance Phragmition communis Koch 1926, order Phragmitetalia Koch 1926, class Phragmitetea australis R. Tüxen et Preising 1942.
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Usage of interactions among plants and pests in biogardens
126-129Views:215Experiences has been gained in the last 25 years with plant extracts, fermented juices, infusions and brews of plant origin presented in present paper. Interactions among vegetables growing in mixed cultures have been also summarized with special regard to insect repellent plants and to those interaction when the target plant’s odour is covered and the pest cannot find it. These methods – after the ecological balance of the garden has been returned – can help the growers to keep the pest density under the economic threshold. The allelopathy can be the basis of the presented results.
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The dynamics of biodiversity structure of soil microorganisms under the impact of biopreparations during potato growing season
67-74Views:275The use of biological preparations such as Phytotsid and Planryz contributes the increase of the general number of soil bacteria population by 13.0–36.1% in the case of potato variety Scarbnytsya and by 4.5–24.6% for potato variety Oberig compared with control. It also increases the number of saprophyte microflora, which compete with plant pathogens, micromycetes, and causes 1.2–1.8 times reduction in the number of soil fungi – Fusarium and Alternaria. During the application of Rovral Akvaflo the Shannon ecological index of species biodiversity is lower than during the biopreparation use. The decrease of species biodiversity was observed as well as strengthening the dominance of some species (dark pigmentation in fungi).
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Status and Prospects of Integrated Pest Management in Apple Production in Hungary
307-316Views:216Farming methods supporting the ecological function of agriculture will play an even more dominant role in the near future than they do now, as much in Hungary as in the rest of the EU.
Several farming techniques supporting sustainable development have already evolved, and in this essay, I deal with integrated production i.e. integrated fruit production in Hungary and its perspectives. I analyze both European and Hungarian regulations on integrated production and their development.
It is obvious that in the orchards of Europe, integrated production is gaining ground. We can expect the increased spread of this western trend to Hungary, too, because one of the conditions for remaining on the market will be a product from integrated production. However, we cannot expect any rapid increase in the future. In my opinion, there are three ways to propagate integrated production:
− changes in the approach of farmers;
− vocational training of farmers because of the greater „knowledge-demand”; improving the consultant network;
− strict monitoring of the production process. -
A partial botanical survey of a gamepreserve
27-30Views:475Hungary is internationally well known for its high level game management. An important part of game management is indoor game keeping. In Hungary more and more game preserves were founded all over the country. The role of these game preserves to retain forest stands outside of the closed area. According to the law, in the game-preserves the game bearing capacity is not the most important parameter, because in these areas the feeding is continuous. In practice it means that in game-preserves we find a much higher density of games than in nature. This causes a relative big loading of the area (of the herbaceous and arboreal), where the game-preserves are located. Our aim is to study the ecological and management issues of forest- and game resources. The scene of these work is a game-preserve related to the Nyírerdő Corporation (Nyíregyháza).
We have done a botanical survey (plant coverage, life-form spectrum) in the three previous units and in the control area (outside of the game-preserve) as well. Our results show the difference in case of the state of herbaceous plants between areas with higher and lower game density. -
Evaluation of reaction to plant density of sunflower hybrids by regression and Kang’s stability analysis
101-109Views:341The world production area and the total production of sunflower has significantly been growing. The harvested yield was 23.4 and 21.1 million ha in 2005 and 2001, respectively. The total sunflower seed production has also unexpectedly increased.
Although sunflower is produced on lower quality soils in Hungary, in 2005 the average harvested yield was 2.43 t ha-1, which was the highest in the world.
Sunflower is a typical commercial plant and fits well in the crop structure. Since in terms of acreage the most significant crops are corn and cereals, the partial monoculture cultivation cannot be avoided. Sunflower production is a way to eliminate this problem, therefore it has an important role both in cultivation and ecological points of view.
Accordingly, sunflower has an important role in reducing the monoculture cultivation of some plants, as well as increasing biodiversity. Sunflower well adapts to Hungary’s climatic conditions and its production is easily practicable in our country.
The reaction of sunflower hybrids on crop density change is different. Some hybrids are more some are less sensitive to this parameter. In different crop years, the crop density optimums of the different genotypes are also different. In Hungary, the yield and quality is primarily determined by fungal infections, while viruses and bacteria are less important.
The research was conducted at the Látókép farm and Regional Research Institute of the University of Debrecen, Centre of Agricultural Sciences. The research institute is situated by Road 33,15 km from Debrecen in the Hajdúság. The duration of the experiment was seven years, 10 hybrids were examined in each year.
Two hybrids used every year, Aréna/PR and Alexandra/PR hybrids were tested by Kang’s stability analysis. We found that Alexandra/PR was most balanced at every levels of crop density. Both hybrids performed most stable yield at 65000 ha-1 crop density level and less balanced at 35000 ha-1 crop density level. As a result of improved environmental conditions, the yield increase of Aréna/PR was higher than that of Alexandra/PR.
Our regression analysis found that the maximum yield of Lympil, Louidor, Hysun 321, PR63A82 and PR64A63 hybrids were harvested at 47000-60000 plant ha-1 crop density level. The statistical analysis showed that the highest yield was harvested from Lympil and Hysun 321. As regards the crop yield, the most stable hybrids were Louidor and Lympil. The optimum crop density interval of Rigasol/PR and Larisol (58000 plant ha-1) was wider than that of Diabolo (46000 plant ha-1). The maximum yield of Larisol was higher at the optimal crop density level. As regards yield, Diabol was the most stable hybrid.
The statistical analysis on the stability of the yield of Alexandra/PR and Aréna/PR showed that Aréna/PR is more stable, and its optimal crop density level is lower than that of Alexandra/PR. -
Recent data about the fish consumption of great Cormorant in the area of Hortobágy Fish Farm Co
75-80Views:478The cormorant (Phalacrocorax carbo) is a bird species that nests sporadically but in colonies, besides larger fishponds and rivers in Hungary. The number of its individuals has been increasing during the last two decades. The species eats solely fish, therefore it can cause serious depredation of the fish stocks in fishponds of intensive system and after the freezing of the ponds, in larger rivers, which are not yet frozen. The aim of our research was to reveal the damages the birds can cause on the studied areas and the extent of the losses the Hortobágy Fish Farm Co. has to realize.
Our studies were carried out between April 2012 and November 2014. During cleaning, the investigation of the craw contents of the birds and their biometric studies were conducted. The results revealed the diverse food base of the species. In the samples, we have determined 379 fish individuals; in 368 cases, the exact fish species were determined, too. Significant differences were found between the consumed fish species rations of the units (P=0.05% beside). We have also found significant difference in the fish consumptions of adult males and females.
Under the ever harder fish production conditions, the presence and thus the permanent predation of the birds affect the fishermen. In favour of maintaining ecological balance as well as to hold the income of the fish farmers, elaboration of adequate protective and preventive methods will be needed in near future.
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Cannibalism and its importance in Aquaculture: A review
43-54Views:1082Intracohort cannibalism may lead to significant losses during the early life stages of farmed fish. The mechanisms driving cannibalism dynamics are common across many fish species and are closely linked to the factors that influence growth variation within a population. This genetically encoded behaviour allows the individual to eliminate competitors in the competition for resources and increases the chances of survival and reproduction. Many fish species display aggression towards individuals of the same species, which can often lead to cannibalistic behavior. This foraging strategy is also present in intensive aquaculture systems, and its economical, ecological and phylogenetic implications have been debated by many researchers. Many fish species can be produced economically in recirculation aquaculture (RAS) systems, but the efficiency of larval and juvenile rearing remains a bottleneck for most species. The success of initial rearing depends on many factors. In addition to genetic factors, the level of cannibalism is mainly influenced by the applied production and feeding technology. Literature suggests that mortality during larval rearing can be as high as 50%, largely due to aggression. In the case of predatory fish species, the presence or absence of certain husbandry conditions can lead to even higher levels of cannibalism, which significantly reduces production yields by causing mortality and secondary injuries, thus further decreasing the survival rate. This review therefore aims to identify and quantify the effects of biotic and abiotic factors that influence cannibalism.
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Regulation in Hungary of the Use of Waste Water and Sewage Sludge in Agriculture
143-149Views:308Regulating the use of waste water and sewage sludge in agriculture in such a way as to prevent harmful effects on soil, vegetation, animals and man.
In European Union there is a Council Directive (86/278/EEC) on the protection of the environment, and in particular of the soil, when sewage sludge is used in agriculture.
In the enlargement process of the European Union the Hungarian Government created a new rule (50/2001. (IV. 3.) Government regulation) which regulate using of waste water and sewage sludge in agriculture. This Hungarian rule is legal and reconcilable with the Council Directive.
The Regulation lays down limit values for concentrations of heavy metals in the soil, in waste water, in sludge and for the maximum annual quantities of heavy metals which may be introduced into the soil.
Waste water, sludge and soil on which it is used must be sampled and analysed.
Sewage sludge must be treated for six months before being used in agriculture.
The use of waste water and sludge prohibited on grassland, on nature reserved areas, in ecological farming, and soil in witch fruit and vegetable crops are growing, with the exception of fruit trees.
The states soil conservation authority must keep records registering the following:
– the quantities of waste water and sludge produced;
– the composition and properties of sludge;
– the type of treatment carried out;
– the names and addresses of the recipients of the sludge and places where the sludge is to be used.
The Government every four years must prepare a consolidated report on the use of sludge in agriculture, specifying quantities used, criteria followed and any difficulties encountered. This report must be forwarded to the Commission.
Last but not least in the light of Member States reports, the Commission will if necessary submit appropriate proposals for increased protection of the soil and the environment. -
Effect of cultivation factors on the yield and yield security of maize
263-265Views:383Cultivation factors have a significant effect on the yield and yield security of maize. Ensuring a suitable green crop is important. Tricultural crop rotation (pea–wheat–maize) in the average of 25 years provided a 2 t ha-1 higher yield compared to monocultural cultivation. A harmonious NPK nutriment supply determines yield and yield security, which can be especially realized by means of the application of precision cultivation technologies. Under average circumstances N 80 kg ha-1, P2O5 50 kg ha-1, K20 60 kg ha-1 active ingredient is the agro-ecological dosage of artificial fertilizer.
Plant density is a factor that determines yield. Optimal plant density – beside the genetic characteristics of the hybrid – is mostly influenced by the level of water and nutriment supply. -
Challenges and agroecological approaches in crop production
75-89Views:296Never has the need been greater for an ecosystem approach to agriculture. As our global population exceeds 9 billion in the next 30 years, with a concomitant demand for agricultural products, ever more pressure will be placed on our agricultural systems. Meanwhile, climate change is altering the ecological settings in which agriculture is practiced, demanding adaptation. Knowledge generated by long-term research will help to address one of the grand challenges of our time: how to meet sustainably the growing world demand for agricultural products – in a way that minimizes environmental harm and enhances the delivery of a diverse array of ecosystem services.
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Possibilities of ecological farming in the North Great Plain Region
69-71Views:186Agriculture plays a significant role in the North Great Plain Region. Organic farming is a sustainable farming method controlled by regulations. Active environmental protection and conservation play significant roles in organic farming, along with food quality and safety, originality and the monitoring of products. Organic farming offers opportunities to create employment, social safety and high profitability. As a result of these characteristics, organic farming could become one of the most important means of developing our region in the future.
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Fish consumption of the great cormorant in the area of Hortobágy Fish Farm
81-84Views:351The cormorant (Phalacrocorax carbo) is a bird species that nests sporadically but in colonies, besides larger fishponds and rivers in Hungary. The number of its individuals has been increasing during the last two decades. The species eats solely fish, therefore it can cause serious depredation of the fish stocks in fishponds of intensive system and after the freezing of the ponds, in larger rivers, which are not yet frozen. The aim of our research is to reveal the damages the birds can cause on the studied areas and the extent of the losses the Hortobágy Fish Farm Co. has to realize.
Our studies were carried out between April 2012 and November 2013. During cleaning, the investigation of the crop contents of the birds and their biometric studies were conducted. The results revealed the diverse nutrition base of the species. In the samples, we have determined 300 identified fish individuals; in 289 cases, the exact fish species were determined, too. Although statistical differences were found between the given pond unit and the consuming of the corresponding fish species (P=0.05% beside), this cannot be considered as absolutely certain.
Our investigation is of considerable significance in terms of nature preservation and not least, it has substantial financial concerns too. Under the ever harder fish production conditions, the presence and thus the permanent nutrition of the bird affect the fishermen. In favour of the maintaining of the natural ecological balance and the income of the fishers, the elaboration of adequate protective and efficient preventive processes will be necessary in the near future.
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Economic Aspects of Rural Tourism
55-71Views:214necessary to ensure the livelihoods of those leaving the agricultural sector and to supplement the incomes of those working in agriculture. I research rural development in four settlements in Hajdú-Bihar County, in Balmazújváros, Hortobágy, Tiszacsege and Egyek, all bordering Hortobágy National Park.
There are many alternative income sources in settlements in the Hortobágy area, such as organic farming, production herbs, hungaricums, small animals and arts and crafts, as well as rural tourism. Rural tourism is not for subsistence, but a supplementary income source, mainly available during the summer time. I made a survey of rural hosts in the four examined settlements, and according to my results, I constructed a model reflecting the cost-benefit relation, as well as the payment period conditions of rural tourism. I am going to show whether it is worth dealing with rural tourism, and if yes, under what conditions. Rural tourism contributes to the maintenance of rural modes of living, in this way it has significant cultural, economic, ecological and social aspects, as well. It is crucial for settlements to create the appropriate conditions needed for joining rural tourism, if it is worth joining at all, and to realise investments for all these. Rural tourism has strict requirements for the levels of environment, infrastructure and services. Studying the Western-European practices, Hungary is lagged behind in the conditions of rural tourism and rural hosts have done their activities mainly out of necessity and not to maintain traditions. Rural tourism may result in success only by co-operation and over the long-run. -
The possibilities and limitations of organic fruit production
41-45Views:192In this review, direct and indirect technological elements of organic production are discussed. Today, there is a growing interest in production prepared without chemicals. We discuss the following issues: site selection, soil, rootstock and cultivar requirements, plant material, planting distances, crown formation, phytotechical operation, irrigation, soil tillage, soil covering and muchning, nutrition supply. Separate section deals with methods of plant protection.
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Testing of paraffin oil efficiency against grape powdery mildew in Eger wine region
73-80Views:597The aim of the present study was to examine the efficiency of paraffin oil against powdery mildew in Eger wine region. The experiment has been carried out in 2013 and 2014 with Chardonnay and Kékfrankos grape varieties, which have different resistance against powdery mildew. The effectiveness of the oil was examined on leaves and clusters (frequency and intensity). This oil was effective against Erysiphe necator infection on field trials in Chile and Brazil. The spread of downy mildew (Plasmopara viticola) was also inhibited by this material in some experiments conducted in Spain and France.
The differences between oil treatments represented the sensitivity of the grape varieties in accordance with the applied dosages. The oil was effective against powdery mildew with different extent as a result of the so called ”vintage effect”. In 2013, the treatment of the highest dosage (D3) didn’t differed significantly in frequency and intensity of infection from the regular treatment (clusters of Kékfrankos, leaves of Chardonnay). In 2014, the oil was not so effective against powdery mildew compared to 2013. No remarkable differences were detected between the treatments due to the strong pressure of powdery mildew. Furthermore, no any effect of the lowest dosage (D1) was detected in the case of the sensitive clusters of Chardonnay and leaves of Kékfrankos in both experimental years.
In summary, the oil treatment has an effect against powdery mildew, however this efficiency largely depends on the vintage characteristics and the pressure of powdery mildew. Further investigations are neccessary, for example field trials with combinations of other sprays. The oil can be useable as fungicide with proper care in eco-friendly integrated and bio (ecological) viticulture.
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Determining elements of variety-specific maize production technology
157-161Views:304Our aim was to work out such new maize fertilizer methods and models which can reduce the harmful effects of fertilization, can
maintain the soil fertility and can moderate the yield fluctuation (nowadays 50-60 %).
The soil of our experimental projects was meadow soil. The soil could be characterized by high clay content and pour phosphorus and
medium potassium contents. In the last decade, out of ten years six years were dry and hot in our region. So the importance of crop-rotation
is increasing and we have to strive for using the appropriate crop rotation.
The yields of maize in monoculture crop rotation decreased by 1-3 t ha-1 in each dry year during the experiment (1983, 1990, 1992,
1993, 1994, 1995, 1998, 2000, 2003, and 2007). The most favourable forecrop of maize was wheat, medium was the biculture crop rotation
and the worst crop rotation was the monoculture.
There is a strong correlation between the sowing time and the yield of maize hybrids, but this interactive effect can be modified by the
amount and distribution of precipitation in the vegetation period. At the early sowing time, the grain moistures were 5-12 % lower compared
to the late sowing time and 4-5 % lower compared to the optimum sowing treatment.
There are great differences among the plant density of different maize hybrids. There are hybrids sensitive to higher plant density and
there are hybrids with wide and narrow optimum plant densities.
The agro-ecological optimum fertilizer dosage of hybrids with a longer season (FAO 400-500) was N 30-40 kg ha-1 higher in favourable
years as compared to early hybrids.
We can summarize our results by saying that we have to use hybrid-specific technologies in maize production. In the future, we have to
increase the level of inputs and have to apply the best appropriate hybrids and with respect to the agroecologial conditions, we can better
utilize the genetic yield potential.