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In 1998 and 1999 a total of 84 samples of corn, predominantly from localities in southern and central Moravia, were collected either directly from fields (entire ears at harvest maturity) or as grain from merchants. The objectives of the experiments were (a) to determine, on the basis of the results from mycological and toxicological analyses, the basic spectrum of fungal contaminants of corn in the Czech Republic with special reference to the genus Fusarium, and (b) to determine by enzyme immunoassay the presence of major toxic metabolites such as deoxynivalenol (DON), T-2 toxin (T-2), zearalenone (ZEA), and fumonisins (FUM) in grain samples. From naturally infected corn, representatives of seven fungal genera were isolated under in vitro conditions in both harvest years. Most frequent were species of the genus Fusarium (mean contamination of 44.6%). The next frequent genus was Stemphylium (29.3%). Eight species of Fusarium were found. In both years the most frequent species was Fusarium graminearum (1998 - 42.75%, 1999 - 41.8%), followed by F. culmorum. DON was found in 95.2% of the samples; its content ranged from 25 to 285 µg/kg. The content of T-2 varied more than that of DON, ranging from 12 to 875 µg/kg. Zearalenone content was more varied than that of the trichothecene-type compounds; 17% of the samples did not contain ZEA, the maximum content was 110 µg/kg. No FUM were found in 17% of the samples; in the others, FUM ranged from 12 to nearly 1000 µg/kg. Compared with the other three compounds, fumonisins showed generally the highest levels.

An outline of past achievements in plant pathology in the CR and main recent problems of Czech plant pathologists are given. A description of the present state in plant pathology in the CR is preceded by data on the structure of CR, on its agriculture, research and development. The outstanding feature of the Czech agriculture is large-scale production. However, the CR still lags behind the EU in yields per hectare. Compared with the EU member states, the CR devotes less money (less then 0.7% of GDP) to research and development (R&D). The trend of state subsidies to R&D in the agriculture sector in current prices is stagnant. It represents an actual decline in the fixed prices. In the Czech Republic, approximately six hundreds persons are professionally engaged in plant health. It represents 6 professionals per 100 hundreds citizens in the CR. Around 160 persons deal with the research and/or teaching of plant pathology. Public service in the field of plant health (advisory work, extension or outreach activities) is one of the weak links in the system of plant health care in the CR. The reason is the lack of commitment for this field of plant health care activity together with absence of sufficient financial support. Minimum requirements for education should be set on advisors and provider of services in the field of plant health at the EU level. In the CR, there exists still some gap in scientific expertise of nematology and integrated pest management. The Czech Lands are proud of the role of some Bohemian and Moravian scientists who have been prominent in the development of plant pathology and related disciplines. These include: AUGUSTUS CARL JOSEPH CORDA and FRANTIŠEK BUBÁK in mycology, GREGOR JOHANN MENDEL in genetics, FRANTIŠEK KRÁL in bacteriology, BOHUMIL NĚMEC and EDUARD BAUDYŠ in plant pathology.

Like spores of many fungi, conidia of Blumeria graminis, the powdery mildew fungus of cereals, release extracellular material. It is released within seconds where conidial surface projections touch a leaf. This ECM is probably adhesive since centrifugation showed that forces greater than those due to normal wind speeds are needed to displace conidia. Also, ECM release is probably involved in rapid sensing of substratum contact, leading to germ tube emergence close to the contact site. Thus, ECM release apparently confers at least two benefits to pathogen survival.

Fourteen Potato virus Y (PVY) isolates were characterized. They represented PVYN strain only. However, application of serological and molecular genetic methods led to a more complicated characterization. For example, five isolates induced necrotic symptoms on tobacco plants typical of PVY^N, despite reacting as PVY^O serologically. Moreover, the PVY isolates were not identical according to molecular genetic properties. Typical PVY^NTN PCR products were observed for 11 isolates, but four of them (Hr220-5, Hr387-7, Nord 242 and Syn1Scot) did not produce potato tuber necrotic symptoms in infected cultivars. An immunocapture RT-PCR probing was developed using a set of 24 primer pairs derived from eight regions of the PVY genome. Using this method, five out of seven PVY^NTN isolates including the Czech standard PVY^NTN from the potato cv. Nicola were found to be identical. However, two PVY^NTN isolates and all the other probed PVY samples showed unique patterns, suggesting specific differences at the nucleotide level. This method enabled specific identification of individual isolates variability even within different PVY strains.

The occurrence and virulence of wheat yellow rust in Hungary was studied in the period of 1999-2001. Yellow rust in Hungary occurred only in traces in 1999, strongly spread and reached epidemic level in Röjtökmuzsaj (West Hungary) in 2000, and the epidemic explosion was in the whole country in 2001. Surveys of yellow rust showed the importance of pathotypes, whose virulence spectra (virulent for Yr2, Yr3, Yr6, Yr7, Yr8, Yr9, Yr17, YrA+, YrCV, YrSD) were able to math the unknown resistance genes. Among 78 Hungarian and foreign cultivars 29 were strongly infected by yellow rust.

The response of 22 winter wheat cultivars to artificial infection with Pyrenophora tritici-repentis has been studied in the field conditions for three years and in the greenhouse conditions as well. The set of cultivars included the cultivars registered in the Czech Republic and Swiss cultivar Arina known for satisfactory resistance to different foliar and head blights. High level of field resistance to Pyrenophora tritici-repentis was detected in cultivars Arina, Vlasta, Rialto, Athlet, Trane, Siria, Vega, Alana, Samara. Not all cultivars showed similar reaction in field and greenhouse tests. Correlation between results of the field and the greenhouse tests was significant for 18 of 22 cultivars. Arina, Vlasta and Vega showed acceptable field resistance and high resistance in the greenhouse tests to Pyrenophora tritici-repentis too. The greenhouse experiments helped to differentiate between examined isolates collected from the territory of the Czech Republic. Cultivar reaction to isolates No. 98001, 98007, 98010, 00071 correlated significantly with the field results.

During trials (1998-2001) in the strawberry's plantation of the cv. Marmolade we monitored the appearance of the most important fungal diseases, their biology and possibilities of integrated control. Monitoring the biology of the determined fungi we established the way of overwintering, appearance of fruiting bodies and discharging of spores as well as beginning of primary infection and first symptoms of the following fungi: Mycosphaerella fragariae, Diplocarpon earliana, Gnomonia comari, Phomopsis obscurans on leaves and Botrytis cinerea on fruits. While checking the efficacy of fungicides, those most effecting to leaf diseases were Folicur Multi and Quadris, and on B. cinerea Switch and Teldor. Testing the resistance on botryticides the fungus B. cinerea showed low level of resistance to anilinopyrimidines and phenilsulfamides and high level to dicarboximides.

In the last decade, the character of agro-food chains functioning has changed significantly. Globalisation elements in the food processing and distribution are changing conditions in agro-food sector and influencing also agrarian markets. Due to higher food finalisation and market force of processing and distribution stages in the agribusiness commodity vertical, farm value share in the final food price has decreased. Increasing competition makes agribusiness firms look for possibilities to strengthen their competitiveness, which is increasingly determined by the ability to develop successful partnerships within commodity verticals, i.e. vertical integration, eventually co-ordination, enforces. In this study, potential benefits and risks of these forms of vertical interconnection are reviewed with respect on specific market and production characteristics of agro-food chains. The problem is presented on the example of the commodity chain of bakery and pasta production in the Czech Republic. At the end of the paper, main arguments for the interconnection of particular stages of this vertical are derived, especially between mills and bakeries.

The paper is focused on the evaluation of the development of financial situation of agricultural co-operatives in the CzechRepublic in 1997-2000 operating in both productive and marginal regions. The comparison of financial situation in these two groups of agricultural firms comes from the classification of firms according to productive regions. Presented results cover firms from the sample of agricultural firms observed in the RIAE Praha. Development tendencies of agricultural co-operatives in these two regions are analysed by means of chosen debt, liquidity, activity and profitability indicators. Non-financial indicators enlarging the above mentioned characteristics of firms' financial situation are suggested and analysed in the last part of this paper.

The effect of infection with Prunus necrotic ringspot virus (PNRSV) and Prune dwarf virus (PDV) on vegetative and reproductive growth of sweet cherry trees (Prunus avium L.) was investigated. Infected trees were smaller and the growth reduction was more severe in Lapins than in Sam; when trees were infected in the nursery (early) compared to an infection two years later in the orchard; and when trees were grafted on the dwarfing Inmil rootstock compared to the more vigorous Damil. Tree mortality after establishment in the orchard was not a problem and only one virus infected tree died during the 5-year observation period. Reduced vigour was accompanied by increased blind wood formation. While the infected trees had a higher generative spur density the total number of generative spurs per tree was less than in the virus free controls, thus reducing yield. In addition the germination of pollen from infected trees was reduced. In general PNRSV has little or no significant influence on vegetative or reproductive behaviour, while PDV significantly reduced both characteristics. The combined infection had dramatic effects, especially on the dwarfing Inmil rootstock with the susceptible cv. Lapins. After four years in the orchard 10% of the initially virus free trees were infected by PDV and 48% by PNRSV.

In birch (Betula pendula Roth) stands of the Děčín sandstone uplands (northern Bohemia) 55 species of leafhoppers were captured using photoeclectors, ground traps and shaking down onto sheets (23,855 specimens of larvae and imagoes). The dominant representatives of the grass and herb undergrowth in birch stands are Jassargus allobrogicus, Anoscopus flavostriatus, Neophilaenus lineatus, Hyledelphax elegantula, Diplocolenus bohemani, Streptanus brevipennis, Macustus grisescens, Planaphrodes bifasciata and Cercopis vulnerata. A heavy abundance of the dominant Oncopis flavicollis and the less abundant O. tristis, weakens birch growth due to the leaf-sucking activities of the insects.

Superoxide dismutase (SOD) isoenzymes of the rumen bacterium Streptococcus bovis 4/1 were studied. Native PAGE showed a single band of Mn-SOD, unaffected by 10 mM cyanide or 5 mM hydrogen peroxide under both aerobic and anaerobic growth conditions. When the metals were removed from the growth medium by Chelex 100, the addition of manganese increased enzymatic activity, while addition of iron inhibited SOD activity. Changes in Mn-SOD and glutathione peroxidase (GSHPx) activities evoked by paraquat and increased values of TBARS indicated that these enzymes were not able to sufficiently prevent oxidative stress at given paraquat concentrations.

A monitoring system for Cameraria ohridella males based on a synthetic sex pheromone was tested in the Czech Republic, Germany, France and Greece. From the obtained data on the insect phenology we concluded that in Central Europe C. ohridella typically has three generations per year. The pheromone monitoring can be used to detect the pest when it appears in uninfested areas and is also suitable to determine population densities.

A rapid, easy to handling and sensitive RNA preparation procedure, RNA release protocol was described here for the detection of Apple stem pitting virus (ASPV) and Apple stem grooving virus (ASGV) by RT-PCR. Comparing total RNA extraction protocol, RNA release protocol give raised similar rate of ASPV and ASGV detection within the field-grown apple cultivars. Among sampling plant tissues, the bud leaf and leaf (during blossom) were showed efficient tissues for the routine detection, regardless the using RNA preparation procedures.

We characterized the genetic diversity of seventy-three C. lindemuthianum isolates collected from 10 different countries by Amplified Fragment Length Polymorphism (AFLP) analysis. The results of this research highlighted the fact that there is huge variation in the genetic diversity between isolates from different countries. The molecular profile of the isolates showed correlation with geographic origin of the isolates.

B. salicis was monitored in willow stands, sampling trees with and without watermark disease. The study focused on Salix alba and S. fragilis. B. salicis - presence was shown not to be restricted to diseased trees. With a B. salicis-specific PCR, B. salicis was frequently detected in the wood of healthy willows. This phenomenon was further studied with PCR-DGGE of endophytic bacterial populations in healthy and diseased willow. B. salicis concentrations were fluctuating during the year, synchronized with tree activity. Water stagnation in the wood as in winter was associated with a high B. salicis concentration, while the sap stream in active trees drained B. salicis from the wood vessels towards the leaves. We concluded that disease risk can not be assessed by testing the presence of B. salicis.

The differentiation between anthropogenic and geogenic loads of the soils by potentially risky elements was observed. The collection of soil horizon samples from 21 localities with different anthropogenic loads (imission fall-outs, floods, historical mining) and geogenic loads (lithogenic, chalcogenic) was composed. The soil characteristics (pH, C_ox), total content of 13 potentially risky elements, content of potentially risky elements in the extract of 2M HNO₃, 1M NH₄NO₃ (mobile forms) and 0.025M EDTA (potentially mobilizable forms) were detected. The solubility as the ratio of total content and the content of risky elements in the other extracts was calculated. The differences between the solubility for each risky element and for each type of the load were determined. It was concluded that the highest solubility was determined in the fluvisols contaminated by the floods and in the soils contaminated by imission fall-outs. Significantly lower solubility of potentially risky elements was determined in the soils with geogenic loads. The efficiency of the used extracts for the differentiation of the soil load was assessed (2M HNO₃, 0.025M EDTA). The types of geogenic loads were characterised in the extent of used soil collection. Geochemically anomalous parent materials and soil types developed on these parent materials were described.

This paper deals with the changes in soil active acidity, mobile aluminium, base saturation, iron and manganese under the influence of quicklime (QL), mixture of soft lithothamnian limestone (SLL) and dolomite (D), and special natural amendments (SNA) based on zeolite tuff. Investigations were carried out on pseudogley of mesoelevations, dystric. The four-year trial was set up according to the Latin rectangle method with 18 trial treatments in four replications. While SNA based on zeolite tuff had little effect on changes of the studied parameters, traditional lime materials (LM), owing also to the fact that they were applied at several times higher rates, had a very positive effect. Soil acidity, iron and manganese were reduced under their influence, mobile aluminium, particularly under their higher rate, was fully blocked or reduced within tolerable limits, and base saturation was raised to a satisfactory level. Effects of SNA depended on the ratio of zeolite tuff and the lime component in them. It could be presupposed that their main efficiency happened in the domain of ion exchange with a positive impact on soil fertility.

Seven cultivars of common buckwheat were tested in field trials under two levels of nitrogen fertilisation on two experimental sites during 1998-2000. The aim of the experiments was to evaluate the influence of cultivar, nutrition and year on main technological quality parameters (thousand achenes weight, volume weight, proportion of fractions on sieves 4.5 and 4 mm, proportion of husks and yield of groats). The differences were observed between buckwheat cultivars in all observed parameters of technological value. Nitrogen fertilisation before sowing (50 kg.ha^-1) did not influence any parameter. On the contrary, buckwheat technological value was influenced by sequence weather (particularly rainfalls) during flowering and achenes formation periods (July). The influence of year was manifested especially on development of endosperm and husks of achenes. Better growing conditions on experimental site Uhříněves caused lower values of volume weight, lower proportion of pericarp (husks) and considerably higher proportion of fraction over 4.5 mm.

Recently we can mention in the CR a step by step enterprise number increase in the area of production, transport services, services and financial organisations, which practically apply internal departments of controlling or audit into their managerial structures. That is why it is required to dedicate a wider publication space to the information on the role and principles of managerial instruments, which are provided by controlling and Internal Audit for business administration and financial management. The goal is to ensure a higher quality of preparation or response on the still emerging forms of our enterprises co-operation with foreign business subjects and to match step at the level of building and in particularly in effectiveness of business informational systems usage for managerial process (especially for planning and decision making procedures control) in all areas of business functions. Internal controlling instruments application and using results of risks evaluations by internal audit simultaneously contributes to the improvement of level and effectiveness of intra-enterprise monitoring as a modern conception of control usage in business management. Management level increase and increase of management competency are the conditions of ensuring our enterprises competitiveness.

The paper addresses the behaviour of Czech farmers in the frames (structures) created by the agricultural policy in Czechia during the period of the Czech agriculture revitalization. The theoretical background of the paper is formed by the duality of actor and structures. The text considers the ideas embedded in the rules of agricultural policy in investigated period as they are confronted with actual behaviour of the Czech farmers. The main assumption is that the circumstances of agricultural policy should primarily increase the competitiveness of the Czech agriculture. Because this issue is a new one, the qualitative approach to deal with these problems was exploited. In-depth (less standardized) interviews with representatives of six farms were conducted. These farms are typical by various strategies of action. The results focus on information about the level of systematic knowledge of agricultural policy, about the specific reactions to particular areas of this policy (incl. farmers evaluation of particular measures related to Czech integration into EU) and about experiences related to the SAPARD program implementation.

This study deals with the founding and development of agrarian political parties and movements in selected postcommunist states (with the emphasis put on the Czech party system in the early 1990's). The topic is discussed from the point of view of classic political science theories, namely the historical conflict approach of Stein Rokkan and Seymour Martin Lipset, complemented with Derek Urwin's theory regarding emergence of agrarian parties as a means of defense of country against urbanization. The results of research into the urban - rural cleavage and its influence on the genesis of agrarian political parties in selected post-communist countries after 1989 seem to support the above mentioned theories (even though those were originally formulated for a much earlier period when the Western party systems were first coming into existence. These can be applied also to the Czech environment, where several profession-based political parties were established in the early 1990's, some of which were concerned with the defense of peasants' and farmers' interests. The attempts to create profession-based parties in the Czech political system were destined to fail for several reasons. The first was a striking ideological profiling of the bipolar party spectrum, causing general parties to pick up the themes and voters concerned with economic recession, and radicalization of electorate. The second reason lied in the diminishing numbers of potential voters, a result of agriculture modernization and general urbanization of society, which caused that the city-country conflict was reflected in the election results only marginally. The result was similar to other post-Soviet states, with a specific exception of Poland: agrarian parties and movements lost their former influence.

The aim of this study was to develop a protocol for production of polyploid M1-generation plants of Viola × wittrockiana Gams. Two variants of colchicine treatment were compared for their efficiency. Early detection of novel ploidy levels was achieved by screening of stomata size, leaf index value (leaf blade length/width), and other morphological characteristics of the M1-generation. Secondary screening for novel ploidy levels was performed by flow cytometry (FCM). Hexadecaploid, aneuploid, and mixoploid plants were successfully identified by FCM.

From the economic point of view the issue is comprehensive namely for its long-term character. At present, there is little experience in complexly understood economic calculations concerning the effect of climate change on forest management. Therefore a new methodology had to be proposed to solve the assigned task, i.e. to analyse the results of research on the effect of climate change on forest management. The issue is closely related to changes in production characteristics of commercial species, i.e. site quality and species composition or health conditions and rotation period of each species and stand. In this case it concerns with a higher proportion of deciduous species at the expense of conifers, namely spruce. This issue also includes the question of further afforestation of non-forest agricultural land, that means the question of land delimitation between agriculture and forestry.

TPY agar supplemented with mupirocin (100 mg/liter) and glacial acetic acid (1 ml/liter) was effective in the enumeration of bifidobacteria in animal (11 species) fecal or intestinal samples. On the other hand, less than 50% of isolates from pig feces were identified as Bifidobacterium sp. using this medium. Subsequently TPY agar modified by the addition of mupirocin (100 mg/liter), glacial acetic acid (1 ml/liter), and colistin (25 mg/liter) was developed for the enumeration of bifidobacteria in pig feces. The results suggest that the bifidobacteria selective media should be chosen in respect of the animal species origin of the samples tested.

ocids are commonly found to be a persistent pest in structures of grain stores. Grain residues are potential pest reservoirs that serve as sources of grain re-infestation. Weight losses caused by psocids on broken wheat kernels were measured. Average weight loss of grain samples was 9.7% after 3 months of Liposcelis bostrychophila infestation. The weight losses were positively correlated with progeny production.

The molecular basis of organ specificity in plant diseases is little characterised. Downy mildew of Arabidopsis caused by the oomycete Peronospora parasitica is characteristically a leaf disease. Resistant host genotypes recognise the pathogen in a gene-for-gene dependent manner and respond with the production of H₂O₂ and the execution of a genetically programmed hypersensitive cell death (HR). We inoculated the roots of Arabidopsis genotypes Col-0, Ws-0 and Wei-0 with the NOCO and WELA races of the pathogen and compared the responses with those observed in infected leaves. Combinations of incompatible genotypes of host and pathogen showed the expected responses of an oxidative burst and the HR in leaves but, surprisingly, roots showed no signs of active defence and appeared completely susceptible to all the P. parasitica isolates tested. RT-PCR showed that the R genes RPP1 and RPP13, which mediate resistance in leaves to P. parasitica isolates NOCO and WELA, respectively, were expressed in leaves as well as in roots. Similarly, NDR1 and EDS1, two components of RPP1-mediated gene signalling pathways, are also expressed in both tissues. Thus, we show for the first time that expression of R genes and at least some of the known downstream components of the signalling cascade are not sufficient for the induction of avirulence gene-mediated defence mechanisms.