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The influence of an interrupted K fertilisation on different K fractions of the soil, yield formation and K uptake by different crops was investigated in a long-term field experiment on Luvisol derived from loess. Irrespective of the previous K fertilisation, the interruption of K fertilisation resulted in a sharp decline of CAL extractable K. K concentration in the saturation extract as well as HCl extractable K were reduced while K fixation capacity increased within 10 years after omitting K. Omitting K fertilisation decreased yields of sugar beet and potatoes while cereals were not affected, although K uptake of all crops reacted to the differentiated K supply to a different extent.

Methods were elaborated that would specify factors affecting the accuracy of the output of LANDSAT satellite images used to evaluate the dynamics of changes in the health condition of birch stands. In the period of investigations, in 1994-2000, the foliage of birch stands was very thin as a consequence of the large-scale absence of flushing in 1997. The output of this method is also specification of the degree of foliage of birch trees based on the altitude, stand age and forest site types in the air-polluted area of the Krušné hory Mts. (Northern Bohemia). These methods can be applied to other broadleaved stands.

The article deals with the evaluation of competitiveness in milling, feedstuffs, pasta, spirits, wine, beer and malt industries in the Slovak Republic. It further evaluates the impacts of economic policy tools on the stated sections of food industry by means of the PAM analysis. The impact of the policies on income, costs and profits of food production in the selected food industry branches has been discovered, based on the effects of divergences and coefficients of nominal and effective protection.

The sugar industry in the Czech Republic is one of the branches of food production that since the end of nineties has been strongly protected by agricultural policy. Here, we will deal with the question how the Czech agricultural policy affected the competitiveness of the sugar industry during transformation. From the analysis, it can be derived that not only agricultural measures but also organisational changes inside the enterprises, as well as modernisation and increasing capacity of plants that all took place before the enforced political aid, supported the stabilisation of sugar beet farming and the sugar industry in the Czech Republic and its competitiveness in the national market.

Listeria monocytogenes represents serious danger for human health. Thus detection of this pathogen in food, which represents its main means of entry into the organism, is a topic of special importance. The original classic methods for the determination of Listeria monocytogenes are in general laborious and time-consuming procedures. In order to address this issue we developed a new rapid method for specific detection of Listeria monocytogenes in food samples. The method consists of three steps: i) enrichment of food microflora (16 h), ii) selective isolation of Listeria sp. exploiting immunomagnetic separation (2-3 h) followed by iii) precise identification of Listeria sp. and Listeria monocytogenes using duplex PCR. PCR primers specific to part of 16S rRNA were used in order to identify the members of Listeria genus. The specific identification of Listeria monocytogenes was accomplished exploiting a pair of primers specific to gene encoding invasion-associated protein - iap (4-5 h). Amplification products, 1003 bp and 593 bp respectively, were separated by electrophoresis and visualized by UV detection. The optimized IMS-PCR method was used to test the presence of Listeria sp. and Listeria monocytogenes in food samples (ground meat, low-fat milk and cheese [olomoucké tvarůžky]). A comparison of the efficiency of the bacteria enrichment step by IMS and centrifugation was also performed. The analysis time including enrichment is less than 24 h. The detection limit for Listeria monocytogenes was found between 101-102 cfu per 25 g of food sample.

Ergosterol is a major sterol in yeast cells. Intermediates of ergosterol biosynthesis or products of ergosterol biotransformation occur in cells too. Sterols mainly form components of cell membranes. Fluidity of membranes is affected by sterols. The amount of sterols in cells can be influenced above all by cultivation conditions and by the yeast genotype. Specific growth rate is an important factor which affects the amount of sterols present in yeast cells. We carried out a series of 24-hour cultivations to find out the impact of specific growth rate on sterol biosynthesis. Inflow of synthetic medium to the bioreactor was controlled by means of a profile of carbon dioxide concentration in the outlet gases. This profile was acquired by simulation according to a mathematical model of cultivation. Profile of carbon dioxide concentration corresponded to a precalculated profile of specific growth rate. Cultivation was divided into two phases with different growth rate values. A constant value of the specific growth rate was maintained in the 1st phase. The specific growth rate value decreased by controlling the inflow in the 2nd phase (beginning at 12th hour of cultivation). Other cultivations were carried out using so-called physiological control which consisted in determining the immediate physiological state (e.g., RQ) and the choice of control strategy according to the metabolic state. Selected control strategy ensures an immediate action (inflow of the medium). If the specific growth rate decreased in the 1st phase, the amount of total sterols in yeast dry biomass increased (to 2.7% in yeast dry biomass). But the purity of ergosterol decreased (amount of sterol contaminants increased up to 23.3% in the sterol fraction). If a constant value of respiratory quotient was maintained (at about 1.1), the amount of total sterols in yeast dry biomass and the purity of ergosterol were constant. If the value of respiratory quotient was changed in the growth and final phase of cultivation, the amount of total sterols in yeast dry biomass increased (to 2.83% in yeast dry biomass). However, the purity of ergosterol decreased (amount of sterol contaminants increased up to 21.2% in sterol fraction).

From 1992 to 1996 the voltinism of the European com borer, Ostrinia nubilalis Hbn., was investigated in Poland. During the study, over 6000 larvae were collected in maize stalks in autumn. In 1994, pupal cases were observed in stalks. This indicated the development of second generation adults of the pest. Pupal cases were not found in other years of the study. The difference between 1994 and the other years was found when the degree-days accumulation at base 10°C was calculated for the periods between July 1 and July 19 (daylight 15 hrs 58 min), or July 29 (daylight 15 hrs 32 min). These values were highest in 1994 and reached 246.5°C, or 414.0°C respectively. The results indicate that degree-days accumulation during the whole year is not responsible for the development of the second generation. It appears that high temperatures in July (not only at the beginning, but also at the end) influenced the development of the second generation of 0. nubilalis in Poland. Average July daily temperatures in 1994 were extremely high (24.5°C). Such temperatures can allow a small partial development of the second generation of O. nubilalis at a relatively cold location like Wroclaw in Poland with a standard annual mean temperature of 8.3°C.

Effects of thermostable lipolytic enzymes Pseudomonas fluorescens 66 ZB in pasteurized milk on concentration of free fatty acids (VMK) in milk were studied in selected milk samples. Identical bulk milk samples were analysed by the method specified in previous papers (Vyletělová et al. 1999a, b, 2000). Reference milk samples (without bacterial strains) and the experimental ones (containing Ps. fl. 150 th. CFU/ml and 2800 th. CFU/ml, resp.) were stored at 6.5°C and 14°C and analysed at regular time intervals (24 h) - Table 1. An extractive-titric method (Kadlec et al. 1996; Table 2 and Fig. 2) was used for monitoring of fatty acid (MK) liberation. Precise analyses of MK and VMK were made by the chromatographic method (Figs. 1, 3 and 4). Medium-chain fatty acids (C12-C16) are liberated first of all; short-chain acids (C6-C10) were found sporadically or in very small quantities (Table 2). Dissociation constant of the specific fatty acid liberated from milk fat affects principally relationships between pH and free fatty acid concentration. The predominating proportion of long-chain acids in liberated fatty acid formation is associated with lower reduction of pH as compared to the predomination of fatty acids with shorter chains associated with more substantial reduction of pH. In our study, a rapid decrease of pH was noted before 168 h (Table 24); this corresponds to low concentrations of short-chain free fatty acids. Vyletělová et al. (2000) found significant relations between pH and contents of VMK (measured by the extractive-titric method); in some samples, correlation coefficients amounted to r = -0.93*** (P ≤ 0.001). The extractive-titric method analysing VMK concentrations (mmol/kg milk fat) provides results characterized by a systematic rise (e.g., 32.0 mmol/kg instead of 13.0 mmol/kg in raw milk). According to Kratochvíl (1992) 20 mmol VMK/kg milk fat signalized the starting point characterizing flavour degradation of milk caused by activities of fatty acids C12-C14 above all; the transformed value (respecting specifics of the extractive-titric method) amounts to 49 mmol/kg. In case of higher storage temperature a significant break is found after 144 h; in case of lower temperature this break is after 192 h (Table 2). Limits determining potential lipolytic modifications of milk flavour (RLZCHV) as related to specific samples and temperatures at VMK levels amounting to 49 mmol/kg or 20 mmol/kg are outlined in Fig. 2. Milk samples No. 5 and No. 6 stored at higher temperature surpassed this risk limit at 56 h and 64 h, respectively (Table 2, Fig. 2). On the contrary, milk samples stored temperatures corresponding to the standard storage temperature (storage of raw milk, transport, storage of pasteurized milk) surpass the mentioned risk level after 90 h and 140.5 h. Obtained results document the predominant role of storage temperature in the whole complex (production and processing of milk as a raw material or an intermediate product); evident differences in contamination rates (105 an 106) can be characterized as secondary effects in this case (Table 2). As related to practical conditions, the mentioned facts imply immediate processing of raw milk and pasteurized milk. This postulate must be respected namely by da

The seasonal dynamics of the pea aphid, Acyrthosiphon pisum Harris, and entomopathogenic fungi from the order Entomophthorales attacking the aphid were analysed in alfalfa and field pea crops during the growing seasons of 1998 and 1999 at Nitra-Malanta. In both years, pea aphid populations on pea showed a pattern with one peak, culminated at flowering and pod formation. The infestation level on alfalfa was low in both years. Entomopathogenic fungi attacking the pea aphid were identified as Erynia neoaphidis Remaudičre and Hennebert and Conidiobolus obscurus (Hall and Dunn) Remaudičre and Keller. Both pathogens infected the aphid on pea, but only E. neoaphidis was found in the alfalfa plots. Infected aphids were not found on alfalfa during 1999. The maximum levels of infected aphids on pea were 10.30% and 48.39% in 1998 and 1999, respectively. During both years alate aphids were more frequently attacked than apteral ones. Correlation coefficients indicated a positive relationship between the number of infected aphids and precipitation, but this relationship was weak or moderately strong. A strong correlation was found between the number of dead aphids and number of alate aphids counted 5 to 10 days earlier.

Wheat semolina and its mixtures with 5% glucose, fructose of sucrose were processed in a sigle screw extruder at the maximum temperature of 140°C and the processing time of 30 s. The nonenzymic browning was only moderate, but it was substantially more intensive in mixtures with glucose or fructose than in the case of wheat semolina or its mixture with sucrose. Red and yellow pigments were mainly formed. The odour acceptability was affected by the presence of sugars almost negligibly, but the intensities were different, higher in extruded mixtures with glucose and fructose than in wheat semolina or its mixture with sucrose. Small differences were observed in the sensory profile. Extrusion of semolina with sugars produced more sensory active volatiles (52-69 identified compounds) than in extruded semolina (41 compounds). Pyrazines, furans and pyrans were the most important sensory active compounds. Their amounts increased by the addition of sugars to semolina; the mixture of semolina with glucose was particularly rich in active compounds. The formation of pyrazines was more enhanced by the addition of fructose than of other sugars. Maltol, butyrolactone and acetic acid were present in large amounts. Even if sensory characteristics were improved by addition of sugars to semolina, the difference was not very pronounced.

In the framework of the study of the mode of action of biocontrol agents (BCAs) it is important to know if BCAs areantibiotic-producers. Epicoccum nigrum 282 and Candida sake CPA-1 are BCAs effective against post-harvest pathogensof stone and pome fruits. The antibiotics produced by these BCAs and the relationship to biocontrol were studied.Production of antibiotics by E. nigrum in in vitro cultures began at 5 days of incubation being maximal at different timesdepending on media used. However, no antibiotic was detected when E. nigrum was grown in a solid state-fermentationsystem or in peaches. In the case of C. sake, no antibiotic was detected either in vitro, in liquid fermentation culturesof the yeast, or in apples.

An effective and fast method for determination of deoxynivalenol (DON) in cereals and flours has been developed. The immunoaffinity column was used for the isolation of DON from wheat, corn, rice and flour extract. The determination was carried out by using the HPLC/UV method. The limit of detection was 0.02 mg/kg. The recoveries for the assay range 0.1 to 2 mg/kg were generally higher than 80%, ranging from 83 to 96% with an average relative standard deviation of 3.8%. The trueness of the method using the DON test - HPLC column was established by use of certified reference material CRM 379. The certified value was 0.67 mg/kg. The result obtained from three replicates was 0.68 ± 0.05 mg/kg. The corresponding confidence interval at 95% probability ranged from 0.63 to 0.73 mg/kg. A comparative study of the DON testTM - HPLC/UV and the Mycosep 225 - GC/ECD methods was carried out. Six naturally contaminated wheat samples were analysed by both methods. Linear regression analysis demonstrates that DON testTM - HPLC is a statistically significant predictor of the GC/ECD method using the Romer Mycosep 225 column.

Two wheat powdery mildew differential sets were tested in the seedling stage in the 2001/2002 season using 192 monoisolates. The data of genotypes carrying the same Pm gene in different genetic backgrounds were compared. Both varieties with gene Pm8 (Salzmünde14/44 and Disponent) were infected by all the isolates. Less than 10% of the isolates gave different responses on varieties with genes Pm2 and Pm3c (6 and 16, respectively). It is doubtful whether the degree of infection of genotypes carrying genes Pm1, Pm4b, Pm5, Pm6 or Pm7 can be compared, while it is completely impossible to compare the data for varieties from the old and new sets carrying genes Pm3a, Pm3b and Pm4a.

The main objective of this study was to determinate the occurrence and intensity of attack by the more important fungal diseases on soybean in Eastern Croatia. Four-year investigation (1998-2001) was undertaken on 10 domestic soybean cultivars with different level of disease resistance. The investigation was set in two planting date (optimal and delayed) on experimental fields of the Agricultural Institute Osijek. Following more important diseases were established: Downy mildew, Pod and stem blight and Stem canker. Significant differences in disease incidence were caused by genetic diversity of tested materials as well as different climatic conditions among growing seasons. According to planting date, significantly higher incidence of Downy mildew and Pod and stem blight was in optimal planting date.

In field trials in 1998-2000, ten varieties of the world collection of birdsfoot trefoil (Lotus corniculatus) were evaluated for herbage and hay yields. In all the years of testing yields from three cuttings and total annual production were evaluated. In 1999, seed yield was also recorded. As a control, alfalfa (Medicago sativa) variety was included in the experiment. The test varieties showed good productivity in the first and especially in the second year of testing, most of them exceeded alfalfa in herbage yield in individual cuttings and in total productions. As for hay yield, the differences were not so great. Local varieties showed very good productivity, predominantly in herbage yields. Of foreign varieties, the best herbage, hay and seed yielder was the Hungarian variety Puszta. There were no statistical differences in seed yield between the varieties. The yields were, however, relatively low.

In 1999-2001 sulfur and sulfate concentrations were studied in expanded young leaves of rapes of the line variety Lirajet and hybrid variety Pronto at the onset of stem elongation (DC 30), flowering (DC 64) and early maturity (DC 70) in different localities of the Czech Republic. Except the S-deficient site the concentration of total sulfur and sulfates in leaves considerably increased in higher growth stages. A less steep increase in S concentration in leaves was associated with rather humid growing season, especially with April precipitation. Great time variations in sulfur concentrations in leaves signal a possibility of diagnostic misinterpretation of plant analysis without exact definition of growth stage. The shape of trend of variations in S concentration in leaves indicates the S nutritive state of the site and the intensity of upward transport of sulfates with soil moisture in the crop nutrition with sulfur. Good yields of rapeseed were connected with minimum concentration of total sulfur 0.5%, and sulfate sulfur 0.2% in leaf dry matter at DC 30. The proportion of sulfates in total concentration of sulfur in rape leaves ranged from 30 to 60% at the onset of stem extension and it increased in higher phenophases. At flowering, sulfates accounted for 80% and more at sites where sulfate uptake from the soil environment was not problematic. Besides the S-soil test, the results of investigations indicate the importance of CEC value of soil for the preventive diagnosis of S-nutrient state of the site.

Height and diameter growth and volume production of 22 different clones of poplars were evaluated in Sliepkovce populetum at the age of 12 years. The populetum is situated on medium-heavy and medium humic uninundated alluvia of the Laborec river; typologically, the group of forest types is Ulmeto-Fraxinetum populeum. The results of evaluation documented that among the poplars under study the clones Gigant, OP-229 and BL achieved the best growth and maximum volume production while their mean height amounted to 22.9-23.8 m, mean diameter to 31.9-33.2 cm and average annual volume increment was 25.1-28.3 m³ per 1 ha. The growth of P. Rochester 20/66 poplar was considerably much slower: its mean height amounted to 17.3 m, mean diameter to 18.7 cm and average annual volume increment was 6.3 m³ per 1 ha. It will be necessary to carry out further studies to obtain more detailed values for these clones.

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 is a part of solution of a post-doctorate grant awarded by the Grant Agency of the Czech Republic (GAČR No. 402/02/P059) connected with the research plan of the FBE MUAF in Brno (GAMSM 431100007), and it focuses on environmental analysis of the brewing industry in the Czech Republic with a focus on the key driving forces in this industry. The basic types of analysed driving forces are the following: long-term growth rate of the industry, character of customers and how they use the product, product innovation, process innovation, marketing innovation, entry/exit of major firms, diffusion of proprietary knowledge, changes in cost and efficiency, buyer preferences for a differentiated product, regulatory influences and government policy changes, changing societal priorities and lifestyles, uncertainty and business risk, and globalisation. Factors identified in the above-mentioned areas are examined also owing to their period of influence, and the possible implications on actions and strategies of breweries are discussed.

In spite of the official goals of support for rural tourism promulgated by governmental bodies, rural tourism remains a marginal phenomenon. This lack of confidence in rural tourism has relatively deep roots. The basis for this is almost of an ontological nature and consists in opposition, although subconscious, against "commodified authenticity". Another source of this lack of confidence lies in the fact that rurality, the main attractive feature of tourism, has been substantially impaired as a result of trends in the 20th century. A third reason follows from the combination of rural tourism and mass recreation, as well as inadequate response by governmental bodies and authorities to the risks for regional stability, based on unmanaged mass tourism.

The reverse transcription polymerace chain reaction (RT-PCR) assay was successfully used for the detection of Apple stem pitting virus (ASPV) and Apple stem grooving virus (ASGV) in four apple cultivars of a 25 years old orchard. These two main pome fruit viruses were detected frequently in all tested apple cultivars. ASGV and ASPV occurred in as many as 16 trees (in the cultivar Spartan) and 13 trees (in the cultivar Idared) out of 20 tested trees, respectively. Mixed infection by ASGV and ASPV was found in all tested cultivars (as many as 9 out of 20 tested trees of the cultivar Spartan).

Control of SVBV relies completely on the use of virus-free planting material, that can be tested either by biological indexing or by molecular methods. A NASBA-based amplification was developed for the detection of SVBV. NASBA is a method based on the primer-dependent, specific amplification of RNA by concurrent activity of a special enzyme mix (AMV-reverse transcriptase, RNaseH, T7 RNA polymerase) at a single temperature (41°C). Specific and sensitive detection of the amplified sequence can be performed in the same tube using molecular beacons. Sensitivity of SVBV-NASBA was 102 molecules of in vitro RNA detected per reaction. Results of the NASBA-based detection of SVBV in indicator strawberry plants were well comparable to the results of PCR.

From 2000 to 2001 the population dynamics of Psammotettix alienus Dahlb. were recorded using a sweep-net or a biocoenometer. The investigations were carried out in Zscherben near Halle (Middle German Dry Region). The imagines of the first generation of P. alienus could be observed for the first time at the beginning of May (2000) and at the end of May (2001), respectively. According to our results, in this area three generations of P. alienus are developed. In both years of our observations the barley-strain of Wheat dwarf virus (WDV) occurred. The main important infections appeared in autumn. Furthermore, during the whole period of our investigations the percentage of viruliferous individuals which were caught was recorded by means of a biological test. In June this percentage achieved 84.0% (2000) and 76.7% (2001), respectively. In the course of summer months of both years the percentage of viruliferous P. alienus decreased. In autumn of the year 2000 an increasing portion followed once again. However, in the year 2001 a continual reduction from > 70% in June to < 5% in late autumn could be observed.

The studies were carried out in a greenhouse of the Agricultural University of Szczecin, during two growing seasons. The aim of this study was determine the effect of the product obtained from radiational SO₂ and NO_x removal from combustion gases on the populations of Globodera rostochiensis nematodes - one of the most common quarantine organisms. The analysis of the effect of the applied product on the population of nematodes demonstrated their varied character of response. In the combination with the product of radiational purification of combustion gases, also significantly lower population density (number of eggs and larvae in 1 g of soil) and lower fecundity of Globodera rostochiensis females were observed compared to the control combination. And in the second year of the experiment, the number of cysts in the combination with the product of SO₂ and NO_x removal from combustion gases was significantly lower compared to the control, and was less than half of the quantity of the previous year.

The monitoring was carried on in the years 1996-2000 in the polyfactorial P-A field trial in Lukavec, Pelhřimov district. The given locality is characterized by low fertility sandy-loamy cambisoils, by long-term average annual rainfall of 653 mm, by average annual temperature of 7°C and its altitude is 620 m. The field trial included different organic fertilizations; graduate N-doses, different soil tillage as well as different forecrops. It manifested in this group of field trials that the forecrop value of red clover and dung manured potatoes before winter wheat was practically the same in the given locality. The optimal N dose for potato yields was about 80 kg N.ha^-1. In oats the yields after red clover with using the Horsch system in spring were significantly lower than after embedding of red clover in autumn. In cereals, graduated N doses increased the numbers of ears (panicles) per m2, but the mass of 1000 grains often decreased. In addition, N content in grain and straw increased with N doses, while pH annually decreased by 0.1 to 0.4.

Parameters characterizing N mineralization and nitrification were measured in soils of ten monitoring areas of the basal soil monitoring carried out by the Central Institute for Supervising and Testing in Agriculture. A remarkable seasonal cycle was found only for nitrate concentrations that reached their maxima in the spring (April-June), and late summer and/or autumn, starting in August. Ammonium ions were nitrified immediately after fertilizer application. Anaerobic N mineralization represented a variable parameter, which was not directly affected by mineral N fertilizers. Nitrification measured by means of one-week incubation was significantly stimulated by N fertilizers confirming that substrate availability was a limiting factor of this process. Short-term nitrification activity (SNA) showed no remarkable seasonal fluctuations, which meant that the potential nitrification rate remained relatively constant during the season. Urease activity was mostly constant during the year and was only slightly related to N mineralization.

A new method for evaluating damage caused by tenthredinids to Norway spruce stands is based on defoliation of the top whorls. A scale with four classes of defoliation was established that is easy to use. Defoliation can be displayed graphically on a grid map (Central European system), in which the map fi elds are delimited by parallels of latitude (6 by 6 minutes) and meridians (10 by 10 minutes) with an approximate size of 11.2 × 12.0 km. The degree of defoliation for an entire forest can be marked by circles of different size in the map field. The range and intensity of an infestation, and the change in defoliation from year to year are easily seen.

Even ten years after the revolution in 1989, Slovak agriculture is characterized by the predominant position of cooperatives. There were shifts towards other types of agricultural entrepreneurship, and some of these trends we documented in our article, based on the data gained by surveying agricultural enterprises. We drew a conclusion that cooperatives are more labor demanding. This also means that they still preserve a social role as a main employer in rural areas. Our paper also differentiates between Southern and Northern (less favorable for agriculture) regions, represented by the Nitra and Žilina region, respectively. We examined soil quality, labor intensity, wages, and finally main crops yields in these two regions.