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The effect of different compost rates on the yield of ryegrass (Lolium perenne L.)
95-98Views:133Protection of natural resources and sustainable natural resources management are essential for the long-term survival of humanity. This makes necessary nowadays the development of environmentally conscious living and spread of that in the future. The amount of organic waste materials, produced during human activities, could be decreased by composting instead of dispose them in landfills. Applying appropriate treatment technology and additives, the compost could be used as fertilizer for horticultural crops and it could increase the easily available nutrient content of soils. Compost utilization prevents nutrient deficiencies and by using the optimal rate, we could reach significant yield increases.
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Describing Fusarium diseases on maize in 2013 using data from several production sites
60-64Views:217As in other parts of the world, the frequency of weather extremes has increased greatly in Hungary in recent years. This means that maize production is faced with greater risks from all aspects: nutrient replacement, irrigation, plant protection. This is especially true of fusarium diseases. In a continental climate, the pathogens causing the most serious problems are species belonging to the Fusarium genus. They infect the ears, which – besides reducing the yield – poses considerable risk to both human and animal health due to the mycotoxins produced by them. Depending on which Fusarium species are dominant at a given location, changes can be expected in the level of infection and in the quality deterioration caused by the mycotoxins they produce. Fusarium spp. not only damages the maize ears but when 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. The degree of infection is fundamentally determined by the resistance traits of the maize hybrids, but also a great role in that region Fusarium species composition as well.
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Fungi detected in trunk of stone fruits in the Czech Republic
121-127Views:240This study was focused on detection of the spectrum of fungi in the wood of stone fruits using molecular genetic methods. Samples were obtained from apricots, plums and sweet cherry trees from region of Moravia, one sample was obtained from Myjava (Slovakia). Segments of symptomatic wood were obtained from dying stone fruit trees with very significant symptoms. This study describes detection of the fungi in the wood of 11 trees in general in 5 localities. The cultivation of the fungi from symptomatic wood and sequencing of ITS was carried out. Eleven fungal genera were determined in the stone fruits wood, particularly Irpex lacteus, Fomes fomentarius, Neofabraea corticola, Calosphaeria pulchella, Cytospora leucostoma, Phellinus tuberculosus, Stereum hirsutum, Collophora sp., Pithomyces chartarum, Aureobasidium pullulans,Fusarium sp. The results of this study demonstrate that the reason of declining of stone fruit trees in Moravia is caused probably by trunk pathogens.
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Evaluation of the role of common vetch (Vicia sativa L.) green manure in crop rotations
161-171Views:206Common vetch (Vicia sativa L.) is an annual legume, grown as green manure provide rapid soil cover, can increase soil moisture and organic matter content and reduce soil erosion during fall. During the fallow period, legumes grown as catch crops are known by releasing large amounts of mineral nitrogen (N) for the subsequent crop. By taking advantage of these benefits, it is possible to increase the yield of the next crop in an environmentally friendly and sustainable way. The goal of this study was to determine the value of common vetch as a green manure, considering its effect on soil conditions and the yield of next crops. We examined three different common vetch seed rate as a green manure in a crop rotation with triticale, oat and corn. Next to the green manured treatments, we used fertilized and bare fallow control treatment for comparison. In our study we evaluated the aboveground biomass weight of spring vetch green manure and its effect on the moisture content of the soil. We examined the green manure’s effect on the next crops plant height and yield. We found that the moisture content of the green manured plots was significantly higher during summer drought. On the green manured plots, 37.9% higher triticale yield, 50% higher oat yield and 44% higher corn yield were measured compared to the control plots. The insertion of spring vetch green manuring into crop rotations could be a good alternative to sustainable nutrient replenishment methods. It can be used to reduce the input needs of farming, reduce carbon footprint, contribute to the protection of soils and increase the organic matter content of the soil.
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Environmental Conditions of the Berettyóújfalu Sub-Region
403-413Views:102The purpose of this paper is to introduce the environmental conditions of the Berettyóújfalu sub-region, which is geographically located in Hajdú-Bihar County. I specifically target the regions’ relief, soil and hydrogeological conditions, climate, flora and fauna, natural value and present nature conservation activities.
On the basis of my investigation of these points, I can state that although this sub-region has unfavorable soil conditions, polluted surface and subsurface waters, it is rich in thermal waters, nature reservations and wildlife. It’s disadvantageous characteristics can or should be amended, while the advantageous ones should be utilized by considering the principles of sustainability. At the end of this paper, I will make recommendations in connection with the latter point. -
The character of the Bódva by the composition of the fishassociations
37-44Views:120The Bódva is one of our rivers that flow outside the Hungarian borders and arrive to the country across the frontier.The Bódva is approximately 110 kilometres long, its upper course is mountaneous- like in its springfield in Slovakia and it reaches the Sajó by flowing among the lower hilly region. The river wall is ravine-like in more places, the river itself is devious, and the water basin is rather variable as in the underlay muddy segments and heavily shingly beds can also be found.
By its fish fauna and physico-chemical characteristics, the Bódva is such aliving water that-after Borne and others (Nowicki, Thienemann) river zone system- can be regarded as an almost uniform typical Barbel zone.
According to our research program (2001-2005) and literature resources we estimated the fish fauna of the Bódva on both the Slovakian and Hungarian course. From some four decades to the wide ecofaunistic examinations of the near past we surveyed the quondam and present fish species of the Bódva River. According to our survey some 40 species compose the recent fish fauna of this river.
In the fish fauna of the Bódva those fish species that presently own a tight ecospectrum, sensitive to the changes of the environment thus so called indicator species, can also be found just like the less sensitive, invasive, aggressively reproducing species. By examining the changes in the fishfauna, the complex of those biogen and abiogen processes that affect the river can be indicated well. It can be stated that the fishfauna of the Bódva is rather rich with a countrywide measure also, and maintain a lot of rare, regressive protected and worth while protection species.
In the last period of the construction, the racial and quantitive composition of the fishfauna of the upper course of the Bódva has changed significantly. Certain species (in the Hungarian course) has vanished almost totally or at least their number declined not ably. Among the vanishing species there are not only a few substantial, protected species of the fauna (e.g. Barbus pelononnesius petényi, Leucaspius delineatus, Zingel sterber, Barbatula barbatula), but the number of the once mass species also decreased appreciably (e.g. Rhodeus sericeus, Alburnoides bipunctatus, Cobitis elongatoides). With the above mentioned changes the number of other animals also decreased in the course that we examined (e.g. mussels, crabs). We examine the cause of these changes in the pollution of the river and according to that in the decrease of the food source and the negative changes of the physico-chemical parameters of the water. -
The effect of increasing compost rates on the yield and nutrient content of ryegrass (Lolium perenne L.)
127-134Views:156Satisfaction of the increasing needs of humanity causes large environmental load. To provide a livable environment for future generations we have to satisfy our needs with the use of sustainable management. This is one of the biggest challenges of nowadays.
The amount of wastes emitted in increasing volume can be decreased by the recycling of them. The disposal of waste materials formed in the public spaces of cities and during the processing of agricultural row materials and by-products in landfills is inconceivable, so they must be recycled.
These materials mostly with organic compounds could be the primary substrates of composts. Completed with suitable additives, and applied appropriate treating technology, composts are capable to supply horticultural plants with nutrients. Composting wastes and byproducts not just decreases the amounts of deposited waste materials, but increases the nutrient (macro- and micronutrients) content of soils, so this is an environmentally friendly and alternative way of nutrient management of plants. -
Biofuel production and its quality standards
137-141Views:130The increasing consumption due to the decreasing amount of fossile energy resources, as well as the increasing fuel prices and living standard will justify the better utilisation of the opportunities lying in biofuel production. Certain countries produce biofuels for their own use or they even export them. However, there are countries which have not decided which feedstock and technology to use. Biofuel – mainly biodiesel and bioethanol – use greatly contributes to environmental protection, decreased CO2 emission and reduced greenhouse effect.
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Chestnut tree: an appropriate choich for rural developement in Europe (review)
55-59Views:147In chestnut plantations or in associations many pathogens and pests can be found. They are causing more than a hundred year problem in chestnut protection, for example the blight fungus Cryphonectria parasitica. Lot of breeders hybridized the Castanea sativa and Castanea dentata with the tolerant asian species. Nowadays the presence of Dryocosmus kuriphilus seems to be the main risk. However, there are more and more chestnut plantations in Europe because of the extensive growth of needs. The food industry produces many products from chestnut, but the wood industry also use it more and more. In most of European countries the chestnut stands represent landscape aesthetics and touristic value, but probably the number of farmers inquiring the plantation will be increase in Hungary.
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The development of the scientific bases of horticulture and the history of horticultural innovation in the Northern Great Plain region and in Debrecen
17-20Views:90It can be told about the second half of the XXth century that, apart from preferring the large-scale growing of field plants and the largescale
livestock farming, corresponding to the central political will of the communist era, the significance and innovation output of
horticultural education in Debrecen was rather of follow-up trait, of secondary importance. The Tobacco Research Institute continued the
research work, and then even this activity was stopped. According to a survey finished in 1997, the mentioned institute had no invention,
granted patent, protection for registered model or any application for patent in progress at the Hungarian Patent Office. Until this time, invention activity at the University of Agricultural Sciences was of medium standard. In the National Patent Office, seven patent applications related to agricultural production and nine patent applications for other fields submitted under the inventors’ names were recorded. In the same period, the Cereal Research Institute (Szeged) led the absolute innovation list of Hungarian agricultural R+D institutions and university education institutes by submitting 164 own patent applications. Both in domestic and international terms, the horticultural innovation conducted at the University of Agricultural Sciences, despite the individual research results and achievements deserving recognition, without appropriate background – remained unnoticed. Let us put it this way: for the past decades, the light of the Debrecen Flower Carnival has not been thrown on the horticultural teachers and researchers of Debrecen. -
Plant growth analysis of wheat populations in a long-term field-experiment
147-151Views:150The experiments were conducted as part of the long-term trial adjusted, in triculture (pea-wheat-corn) and biculture (wheat-corn), at three nutrition levels, with the use of one crop protection technologie (conventional) at the Látókép Research Site of the Centre of Agricultural Scienses, University of Debrecen, on a chernozem soil. The wheat variety used in the long-term trial was GK Csillag, which was sown at 5,8 million germs/ha.
The effect of pre-crops and nutrient-supply levels on some growth-parameters (LAI, HI, LAD), just as SPAD-values and yield amounts of winter wheat has been investigated in this experiment. We tried to find out the extent of relationship between the different parameters, so we determined the relationships between different nutrient-supply levels, yield amounts, LAI- SPAD- and LAD-values – measured in the crop-year of 2010–2011 in different crop rotation systems – by using correlation analysis. It has been stated both in case of bi- and tri-culture crop-rotation systems that different fertilizer dosages had significantly affected the leaf area index dynamics and its maximal value, and that increasing N+PK fertilization has
significantly increased the duration of leaves, as well. The highest SPAD-values were measured during the flowering and grain filling stages. However, we haven’t revealed significant differences between all fertilizer treatments. In case of the bi-culture crop-rotation system harvest index values showed an increasing tendency parallel to the increasing nutrient-supply levels, while in case of the tri-culture system this tendency was rather decreasing. However, these differences were
not significant. Parallel to the increasing fertilizer dosages yield results were increased in a significant extent. At the same nutrient supply-levels 2088–4615 kg ha-1 higher yields were measured in the tri-culture than in the bi-culture system. The correlation analyses have confirmed that all of the investigated parameters (yield amount, LAI, SPAD, LAD) had almost in all cases close positive correlation to the nutrient-supply level and the yield amount in both crop-rotation systems. These results have confirmed that the leaf area, the leaf duration, the SPAD-values and the fertilization have altogether resulted in the production of maximum grain yields. -
Contributions to the 2014 and 2015 flight pattern and damages of Carpomyia schineri Loew.
96-99Views:143The fly Carpomyia schineri Loew is a pest of the berries of the feral Rosa canina group but is can also be found in the berries of grown rose cultivars. The larva damages the flesh of the berry, several larvae can develop inside a single berry. It can decrease the quantity and ascorbic acid content of the tea and jam, which are important human ascorbic acid sources during winter. At the same time in trapping experiments the adult can be confounded with adults of the walnut husk fly (Rhagoletis completa Cresson). In collections of berries at several sites in Hungary damage levels ranged from 0.88% to 65.08 %. Based on these damage levels we had the impression that the yellow sticky traps CSALOMON® PALz or PALs baited with the synthetic Rhagoletis lure caught moderate numbers of adults and were not satisfactory for detection, consequently improving trapping methods is necessary in the future.
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Study of a Turkey Population for Gene Preservation
48-52Views:173Genetic variability is very important in small populations. We examined an indigenous bronze turkey population which is bred for gene conservation in order to see if the current mating system maintains genetic variability. The present generation was surveyed using microsatellite markers and a computer model was used to simulate changes in the population over 100 generations.
The data was analysed using the concept of entrophy from information theory instead of genetic variance so that we could more accurately measure genetic variability.
The results indicate that the breeding method currently in use, rotational line mating, is acceptable with respect to preserving genetic variability, but new selection methods may provide additional protection against the loss of alleles. -
Agronomical and Economic Evaluation of Different Soil Cultivation Systems
17-22Views:88In the interest of profitable plant production and environmental protection we have to make an effort to protect and improve the productivity of our soils while moderating production limiting factors. Due to different soil cultivation methods, the quantity of yield and required expenses also differ.
We examined the production costs in four different production technology systems. Overall, it can be said that farming standards are good, since cost prices were low (2001: 14-15 HUF/kg, 2002: 15-21 HUF/kg, 2003: 39-49 HUF/kg) in the case of all main products per 1 kg. Cost prices were lowest in the case of direct sowing, probably due to low machinery costs.
All economic indicators have to be compared when choosing the most suitable production technology in a specific farming environment. -
The hydric stress influence on quantityand quality of the maize yield in the Crisurilor Plainconditions
21-27Views:134The paper is based on the researches carried out in an experiment placed on the preluvosoil from Agricultural Research and Development Station Oradea, Crisurilor Plain during 2008–2011in the following variants: V1=Irrigated, without irrigation suspending; V2=Irrigated, irrigation suspending in May; V3=Irrigated, irrigation suspending in June; V4=Irrigated, irrigation suspending in July; V5=Irrigated, irrigation suspending in August; V6=Unirrigated. The hybrid used: Fundulea 376. In the variant with optimum irrigation, water reserve on 0–75 cm depth was maintained between easily available water content and field capacity. Pedological drought was determined every year and the irrigation was also needed. The irrigation determined the increase of the total water consumption and yield gain in comparison with unirrigated variant. Irrigation suspending in different months determined the yield losses very significant statistically. The biggest protein content was registered in the variant without irrigation suspending; the values registered in the variants with irrigation suspending in May, June, July and August and in the unirrigated variant are smaller, with differences statistically assured. There was a direct link between de Martonne aridity index values and water consumption, yield and protein content and an inverse link between pedological drought and yield quantity and protein content. These are the arguments for irrigation opportunity in maize from Criurilor Plain.
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Change of soil nitrogen content in a long term fertilization experiment
39-44Views:159The most important aim of sustainable agriculture is to ensure our natural resources – such as soils – protection, which includes fertility preservation and the use of appropriate methods of cultivation.
If we want to get accurate information about the occurred changes, way and danger of changes, we should track the resupply and effect of the mineral nutrients and the removed quantity of nutrients with the harvest.
Nitrogen is an essential element for living organisms and it is present in the soil mainly in organic form. In general only a low percentage of the total nitrogen content can be used directly by plants in the soil. The mineral nitrogen is incorporate by plants into our bodies. This inorganic nitrogen is produced by the transformation of organic contents through mineralization processes and it gets into the soil by fertilization. This is how nitrogen turnover occurs when mineral forms become organic and organic forms become mineral.
The objective of this publication was to introduce – through some element s of nitrogen turnover- how changing the properties of soil in a long term fertilization experiment.
We established that the fertilization is influenced the soil pH. With the increase of fertilization levels increased the acidity of the soil, maybe it is related with the number of nitrification bacteria. The fertilization and the rotation affected to the quantity of nitrate.
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Previous data on the relationship between the intensity of pruning and the degree of damage in integrated and organic applegrowing systems
47-52Views:107In Hungary, fruit growers are increasingly interested in environmentally friendly growing methods, such as organic and integrated systems. Vital is the establishment of a strengthened system of cultivar-pruning-plant protection in production technology. Consequently, our aim was to examine the susceptibility of apple cultivars to diseases and pests and the effect of pruning technique on diseases and pests in organic and integrated growing systems.
Two pathogens (Venturia inaequalis, Podosphaera leucotricha) and two pests (Leucoptera malifoliella, Pannonychus ulmi) were observed in organic and integrated systems under „strong” and „weak” pruning techniques. Our results on six cultivars showed that the pathogens and pests infested the trees more in the organic system, as compared to that of integrated production. The pruning technique affected mainly the susceptible
cultivars to diseases and pests. The „weak” pruning technique caused a higher level of diseases and pests infestations than the „strong” pruning technique, especially in the organic growing system. The likely reason is that the shoots grow fast and powerfully under “strong” pruning technique. This supports better preservation of the trees supported by susceptibility of plant tissues to diseases and pests. -
Bioreactors in Hungary
248-254Views:122The transformation and utilization of organic materials must occur with the highest degree of environmental conformity. This conformity – in accordance with the guiding principles of the European Union – will result in a new economic and systematical approach. We can establish the profitability of projects with the utilization of surplus effects which characterize multiple-product lines.
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Violation prooxidative-antioxidant stability at maize shoots at different level of accumulation of cadmium and nickel
89-94Views:75Joint influence of cadmium and nickel was investigated on the feature of their accumulation by the vegetative organs of 10-days' old maize shoots. It was established that most intensively noted metals are taken in by the roots of shoots in the first 7 hours stressing influencing, while in leaves they appear only after a 7-hour long exposition. It was stated that the absorption process of the noted metals by a root system is carried by two-phase character. The indexes of inner-tissue contamination are calculated. Activating by the cadmium and nickel ions of lipid peroxidation as marker of the stressing influencing, and also was shown the proper increase of intensity of functioning of ascorbate peroxidase as the antioxidant enzyme protection of cell.
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Alternatives of microclimate control in orchards
209-212Views:172The aim of the study was to find out which of the methods used to avoid damages of late frosts would be the most effective for the fruit growing practice. We tested the antifrost irrigation method in Debrecen-Pallag. For that purpose microjet sprayers are used, which are thrifty and does not need for that purpose large containers. With the aim to secure an even distribution of water, the sprayers are distributed on three levels: above and inside of the crown as well as on the level of trunks. On a large scale, a single microjet above the crown level would be sufficient. By means of a detailed analysis served to set the optimum intervals between spraying phases: with each 15, 10, 5 and 3 minutes during half a minute. The synchronous presence of water and ice below the freezing point, the released freezing heat plus the water used much above the freezing point
(9–10 °C) altogether maintains the temperature above around 0 °C near the flowers or growing fruitlets, meanwhile, the surrounding air cools down to -8 °C. The effectiveness of the generally used antifrost would be increased substantially by the former application of cooling irrigation, which delays the blooming date. -
Practical experiences of a designing and operating a pilot aquaponic system
27-32Views:335Aquaponics is the combination of fish farming (aquaculture) and the soilless cultivation of plants (hydroponics). The aquaponics system is an artificial, recirculating ecosystem, in which bacterial processes convert the waste materials in the water used for fish rearing into plant nutrients, and therefore with the generated heat it is suitable for culturing economically valuable plants, and thus it mitigates the nutrient laden and quantity of the intensive fish producing systems’ effluent water.
The primary goal of our 12 separate unit’s aquaponics system was to gain experience. We would like to find the right plant species, which are fit for that medium, and their crop can be sold. Besides the plants, our attention focused on the fish. Two fish species were included in the experiments, the common carp and barramundi. It was difficult to create them a perfect living space, besides a constantly changing conditions temperature. Apart the above mentioned we had a problem with the number of individuals per tank, the deformity of the fish body and the too high volume of pH (we registered continuous values above 8.4). We get by carps 4.7 grams of weight gain during 15 weeks, because of the bad conditions.
The main problems at the plants are caused by aphesis and protection against sunburn. Even so we have got the multiples of field yields for each plant species. At salad has grown twice of field yields, tomatoes one and half, kohlrabi than 3.5 times more. The causes of multiple yields are the continuous balanced water and the nutrient uptake of plants. Each plant species fit for cultivating in aquaponics and their crops are delicious, chemical -free, safe and marketable. The plants should be more concentrated. After the experiment, it has been determinated that the carp is suitable for aquaponics, but greater weight gain could be achieved with optimal selection of size of rearing units.
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Essential oil extraction from herbs and their use in the food industry
59-74Views:383Essential oil extraction of wild caraway and thyme was performed using a classical (HD) and microwave hydro-distillation (MWHD) and a laboratory supercritical fluid extraction (SFE) with a carbon dioxide as solvent. Our experiments demonstrated that the extraction yield of the essential oil performed in same conditions was influenced by the location of growth area; the maximum extraction yield of 10 ml 100 g-1 caraway was obtained from dried seeds collected from Csíkmadaras. This quantity far exceeded the yield of the Újtusnád samples. In the case of wild caraway (Carum carvi L.), the extraction method influenced thecomposition of the essential oil (carvone/limonene ratio), the highest limonene content being achieved by classical hydro-distillation. In the case of thyme, this effect was not detected, the thymol/carvacrol ratio was independent from the given extraction method. The obtained thyme essential oil possesses high antimicrobial activity demonstrated by agar diffusion test. The thyme extract provides a good protection against microorganisms collected on the surface of fresh vegetables following bacterial stains: Citrobacter portucalensis, Pseudomonas hunanensis, Pseudomonas baetica, Pseudomonas parafulva, Bacillus mojavensis and Enterobacter cloacae. Protective effect was also detected on the vegetable surface of by chitosan-based edible film coating during a 6-day-long storage period at a temperature of 4 °C. The caraway essential oil used as soft cheese seasoning with a direct, dilution-free method, proved to be unsuitable because the uneven distribution and confer a strong, unpleasant taste to the product in comparison with the ground wild caraway seed-dressed cheese.
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Environmental Indicators – Agri-Environmental Indicators
248-255Views:90close relation. This means that policies related to the economy and the environment cannot be handled without each other. The United Nations Conference (Stockholm, 1972) was the first global conference to signal that environment concerns have increasingly become subject of mainstream socio-economic policies. The process started in the Seventies, laying emphasis on environment protection, plays an important role in the policy of international agencies. The use of environmental indicators is essential for monitoring the effects of environmental measures. The best way of evaluating sustainability if the results can be compared on a global level. International efforts are being made by the United Nations (UN), the Organisation for Economic Co-operation and Development (OECD), the Statistical Office of the European Commission (Eurostat) and other international agencies to develop a framework for environment statistics. This study deals with these frameworks, paying attention to agri-environment indicators. Hungary became a member of the UN in 1955, of the OECD in 1996, and will become a member of the European Union in 2004. The first summary in connection with environmental indicators of Hungary, taking the OECD Pressure – State – Response framework as a basis, was published in 1994. As a result, comparability of environmental indicators for Hungary with those used international are given.
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Occurrence of woolly cupgrass (Eriochloa villosa /Thunb./ Kunth) in Hajdú-Bihar county, Hungary
119-123Views:104Woolly cupgrass (Eriochloa villosa /Thunb./ Kunth) is native to East Asia, it spreads in several parts of the World and causes difficulties in plant protection, especially in maize. Difficulties in control of Eriochloa villosa originated from several reasons: seeds continue to germinate later in the season, significant part of seeds emerges from a deep layer of the soil, and the species is less susceptible to some herbicides applied to maize than other annual grass weeds.
The first report on the occurrence of woolly cupgrass in Hungary was published in 2008, and it reported about the appearance of this species near to Gesztely village (Borsod-Abaúj-Zemplén county), however, no information has been added about spread of the weed in Hungary until now.
A significant population was discovered next to Debrecen (Hajdú-Bihar county) in summer, 2011, and then weed associations were examined in maize, sunflower and stubble-fields on several km2 in the area to estimate the Eriochloa villosa infection. The weed species was found on every maize field bordering with a ground cover of 0.5-4%. Woolly cupgrass occurred inside of the 50% of maize fields, and reached a ground cover of 76% in case of most infected area, in addition it was found in sunflower and stubble-fields.
The spread of woolly cupgrass is expected in this area, which requires the consideration of this species in the planning of weed management technologies. -
Old-new disease is maize smut (Ustilago maydis)
43-46Views:216Corn smut disease (Ustilago maydis) is one of the most common maize diseases. In the previous years the disease lost some from its importance, however nowadays it turns into more and more important and widespread one. The control encounters great difficulties, therefore it should be emphasized the preventive and resistance-based protection.