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In small-plot field trials conducted in 2000-2002 we studied the effect of fungicides on the yield and selected technological parameters of grain of malt barley and on malt. For the treatment we used Cerelux (active ingredients: fenpropimorph, flusilazole), Amistar (azoxystrobin) and Caramba (metconazole) applied in two stages of stand development (DC 47 and 55). Compared to the untreated control plants the yield grains ranged between 6.9 and 16.5% after the application of fungicides. The application of fungicides increased the proportion of full grains and had a favourable effect on the chemical composition of grain. After the treatment with azoxystrobin the content of N-substances decreased from 11.43 to 11.07% as compared to the controls. The highest starch content of grain was observed after the application of the active ingredient metconazole; the average content ranged between 64.44 and 64.62%. Compared to the controls the highest relative yield of malt starch (124.2-125.2%) was achieved after the application of azoxystrobin or a combination of azoxystrobin and metconazole in the DC 47 stage. The highest average attainable degree of fermentation was 78.57% and was discovered in the untreated control.

In greenhouse conditions a 3-year small-plot experiment was conducted on loamy Chernozem originating from the humus horizon to investigate the effect of sodium humate application on yield, nitrate content and vitamin C content in green pepper fruits. The application of 5 kg of sodium humate per hectare in the form of watering 3 weeks after planting of pepper seedlings under full NPK nutrition (N nutrition was divided as follows: 2/3 of total N before planting and 1/3 of total N together with sodium humate 3 weeks after planting) resulted in a statistically significant increase in pepper yield by 13.6% at a concomitant significant reduction of nitrate content in pepper fruits by 12% and increase in vitamin C content by 28.6%.

Following measurements of dead wood (20 to 40 years) at various developmental stages of the life cycle of selected virgin forests of the 1^st to 7^th altitudinal zone the relation of its course was derived. The dynamics and course of dead wood in the life cycle of virgin forests were best represented by a polynomial of the third degree. An analysis confirmed that virgin forests consisting of stable tree species with approximately the same physical age (Boky) showed small differences between maximal increase and decrease in necromass during the whole development cycle. Virgin forests at sites rich in nutrients consisting of several tree species with various physical age had high values of necromass during their whole development cycle. Spruce stands at the upper forest boundary also had a relatively high ratio of necromass at the advanced optimum stage.

Summarization of the potential of introskeletal erosion (ISE) was done on the basis of field surveys in the Šumava Mts., Krkonoše Mts. and Jeseníky Mts. areas. The results give a rough estimation of the ISE extent in mountain forests of the Czech Republic. They indicate that in the mountainous areas of the Czech Republic there are 46,535 ha of forest lands endangered by these processes, which represents 10.1% of mountain forests and 1.7% of the total forest area in the country. The worst situation is in the Krkonoše Mts., where the considerable ISE potential is on 30.5% of forest area (in the Jeseníky Mts. 16.6%, in the Novohradské hory Mts. 13.3%, in the Šumava Mts. 8.2%). Because these areas are relevant production and water protection areas, the ISE processes have to be studied carefully and forest lands have to be protected, also using special technologies for forest protection and restoration.

In the paper, there is described using of the optimization models AGRO-3 SR for modeling food production chains in the Slovak Republic (the modified version of the Czech model AGRO-3) and ALOKA for optimal allocation of the domestic agricultural production computed by AGRO-3 SR into 4 different regions of the SR for simulation of consequences of various types of agrarian policies on the effectiveness of the Slovak agriculture to the medium-term horizon 2005. There are formulated and evaluated 4 scenarios for the model AGRO-3 SR and two alternatives A and B for the model ALOKA relating to all scenarios. Results of simulations have shown that the best result was reached in the scenario 4 by the price liberalization in the whole food chains.

The paper analyses the economic and policy gap between the agriculture in Slovakia and the EU member states from the perspective of the future accession of this country to the Union. As it concludes, the deterioration of terms of trade during the transition period creates also problems for the accession negotiations, because this fact seems to legitimate the equitable implementation of the CAP in all member countries after the East-enlargement of the Union. The paper is arguing, on the basis of income simulation, that that the Commission proposal on reduced direct payments for the newly admitted countries would, in case of Slovakia, generate an improvement of the sectoral income only if they are topped by rural development measures.

A high level of communicative capabilities as an integral part of social skills in managers is an essential prerequisite of success in managerial position. The paper points out an opportunity of quantifying the level of communicative capabilities, as well as the way of delimiting deficiencies in communication and planning the process of development of communicative capabilities. The testing was done on a sample of 230 students of the Faculty of Economics and Management, Slovak University of Agriculture in Nitra, i.e. in the future agromanagers.

In the present paper genetic relationships of twenty varieties of cashew are described on the basis of morphological characters and RAPD (Randomly Amplified Polymorphic DNA) markers. Results obtained for the phenotypic characters based on similarity coefficient were divided into four clusters with 70% similarity. By means of similarity coefficients (SG), cluster I was found to consist of twelve varieties. Cluster II consisted of a single variety, NRCC-1, cluster III consisted of six varieties and cluster IV had only one variety, Vridhachalam-2. The analysis started by using RAPD markers that allowed us to distinguish 20 varieties. A total of 80 distinct DNA fragments ranging from 0.2 to 3.0 kb were amplified by using 11 selected random 10-mer primers. Genetic similarity analysis was conducted for the presence or absence of bands in the RAPD profile. Cluster analysis clearly showed that 20 varieties of cashew grouped into two major clusters based on similarity indices. The first major cluster comprised one minor cluster. The other major cluster was divided into two sub-minor clusters, one sub-minor cluster having three varieties and the other sub-minor cluster was represented by 15 varieties. Among the 20 varieties, Ullal-3 and Dhana (H-1608) showed the highest similarity indices (87%). It was noted that Vengurla-2 and Vengurla-3 were not grouped into a single cluster but Vengurla-4 has 82% similarity to Vengurla-3. The variety Vengurla-2 has very close similarity (85%) with variety Vridhachalam-3 (M-26/2). The analysis of genetic relationships in cashew using morphological traits and RAPD banding data can be useful for plant improvement, descriptions of new varieties and also for assessment of variety purity in plant certification programmes.

Sewage sludge application in agriculture is the simplest method of its management. Its content of organic and inorganic toxic components is a barrier to such management. Particular attention should be paid to the content of heavy metals whose presence in sewage sludge and later in soil poses hazard for plants, animals and people. The investigations aimed to determine the effect of vermicomposts obtained from tannery sludge on development of the root system and biomass of shoots as well as heavy metal concentrations in these organs. In the first year after the vermicomposts application their effect on the maize biomass increase was equal to the farmyard manure treatment but significantly worse than the mineral fertilization. The consecutive fertilizer effect of vermicomposts of tannery sludge ted on the increase in biomass of the shoots and roots of winter rape, sunflower and oats was comparable with the farmyard manure effect but notably better than the mineral fertilization. Heavy metal concentrations in individual plants were diversified; in the plants from vermicompost treatment they were as a rule lower than in the plants from mineral or farmyard manure treatment. Absorbed heavy metals accumulated primarily in the root systems, whereas the extremely high chromium content in vermicomposts did not cause its excessive accumulation in the cultivated plants.

A laboratory incubation experiment with zeolite and glucose was performed to evaluate the effects of zeolite amendment in heavy metal contaminated soils from two smelter areas on some microbial characteristics [Kremikovtzi (K1, K2) in Bulgariaand Příbram (P1, P2) in the CzechRepublic]. The content of microbial biomass showed a tendency to decrease in Kremikovtzi soils whereas in Příbram soils no significant effects were found after zeolite amendment. Respiratory activity and metabolic quotient (qCO2) decreased on the second and third day in Kremikovtzi soils amended with zeolite, no effects were observed in Příbram soils. Heavy metals decreased the content of microbial biomass in Kremikovtzi soils whereas the contaminated soil from Příbram area had the highest microbial biomass compared to non-contaminated soil during incubation, probably due to lower mineralization of carbon. The respiratory activity did not show any significant effects of zeolites on the evolution of CO2 and qCO2 in heavy metal contaminated Příbram soil. The respiratory activity in non-contaminated Příbram soil remained during the experiment lower in comparison to contaminated one, however the addition of zeolite increased qCO2.

Tree mortality was recorded in a selection orchard of maintenance breeding of cv. Bergeron LE-2 in 1993-2002. The beginning of blossoming was examined in individual trees in the same orchard in 1999-2002. Considering the effect of year, a maximum difference in the average beginning of blossoming was 10 days in the whole set of trees. The beginning of blossoming of individual trees was not identical in the same year. A difference in the onset of phenophase "beginning of blossoming" between early and late blossoming trees was 1-4 days in the particular years. The trees maintained their early or late blossoming for the whole period of evaluation. No tree died in the orchard by 1998. From 1999 to 2002 50% of early blossoming trees died and only 2.38% of late blossoming ones (average of three replications). Two thirds of early blossoming trees died during vegetation, a third died during vegetation rest. No commercially important viroses were proved to be present. It is the reason why viruses could not be a potential cause of the above-mentioned facts. The presence of phytoplasm (ESFY) was confirmed by the method NESTED PCR in one case in a randomly selected early blossoming tree. The test was negative in two randomly selected late blossoming trees from underplanting. The early beginning of blossoming did not influence productivity. Correlations between the beginning of tree blossoming and blossom abundance, or between the beginning of blossoming and productivity, were insignificant (r = 0.12 or r = -0.13). Even though the causative agent of higher mortality in early blossoming trees was not confirmed unambiguously, it is desirable to select the best individuals only from the group of late blossoming ones during maintenance breeding of cv. Bergeron. These individuals should be used as prebasic material in a certification process and as basic material after prescribed repeated testing.

The goal of the measurement of the tractor ZTS 164 45 equipped with digital electrohydraulical control EHR-D BOSCH during ploughing with ploughs KUHN (4 bottoms) and 5 PHX 35 (5 bottoms) was to obtain time dependent states of pressure in the hydraulic system of the three point hitch of tractor. From the point of view of comparison of obtained results testing conditions were determinated with respect to physical and mechanical properties of soil such as soil volume mass, soil humidity, penetration resistance and shear resistance of soil. Beyond these measurements also measurements of operation parameters as a ploughing depth, ploughing width, working speed and fuel consumption were accomplished. The measured results of physical and mechanical properties of soil show big content of loam elements and stones in the soil. Simultaneously the measured results of the operation parameters of the ploughing sets confirmed that the ploughs KUHN and 5 PHX 35 are suitable for tractor ZTS 164 45. Based on the measured results there is a possibility to infer following conclusions: Control system of the three point hitch offers a reliable function. Hydraulic circuit is equipped by an improper distributor which causes pressure peaks which are corres-ponding with safety valve adjustment. Hydraulic circuit has a low conductive resistance. Loading of tractor body is higher when using mounted plough than with semi mounted plough.

The paper is based on a special sampling survey of farms that was conducted under EU PHARE ACE research project P97-8158-R "Micro-economic Analysis of Farm Restructuring in Central and Eastern Europe" in 2000 in one of the NUTS 2 regions of the CR - in the South-East region. The region involves two administrative regions - Vysočina and South Moravian NUTS 3 and consists of subregions with different natural and market conditions (of hilly, lowland and suburban type) representing the conditions of agricultural production in the Czech Republic as a whole. The main results of the survey focused on farms of three different categories are presented: farms as legal entities (separately agricultural production cooperatives, joint stock companies and limited liability companies), officially registered individual farms of different size (formally licensed to business activities) and unregistered individual farms including small farming units - households with self-sustaining agricultural production.

The paper deals with statistical analysis of the registered regional unemployment rate in regions and districts of the Czech Republic from 1998 to 2002. Regional unemployment reaches significantly different levels; moreover, within the examined period, differences were increasing: variance between the minimum and the maximum increased approx. from 12% to 20% in the respective districts. By means of cluster analysis, regions are divided into more homogenous groups according to the registered unemployment rate by 31 December 2002. The following districts may be identified as the best ones: Praha-západ (Prague-West), Praha-východ (Prague-East), Praha (Prague) and Benešov; the following as the worst ones: Most and Karviná. Concerning regions, the lowest unemployment level may be identified in Praha (Prague); on the contrary, the highest levels were reached in Ústecký region and Moravskoslezský region. Variability, skewness and peak characteristics were calculated to evaluate the development of regional unemployment distribution. The average rose from 5.63% to 9.94%, the standard deviation rose from 2.53% to 4.15%, the variation coefficient stayed around 0.4. Thus, together with the increase in unemployment level, the absolute variability rose while the relative variability stayed approx. constant. The rate distribution was left-sided and increasing; the peak was only slightly higher than the standard peak. The development trend of the characteristics was evaluated by means of linear functions and higher order polynomials; their seasonal variation is described by seasonal indices differing in the degree of their seasonality and distribution in the course of a year. A correlation matrix demonstrates the relations between the trend of the characteristics and their seasonal indices.

Four protein fractions: 1 - albumins and globulins, 2 - gliadins, 3 - glutenins (extracted in NaOH), 4 - glutenins (extracted in SDS) separated by SDS-PAGE were used as biochemical markers for evaluation of polymorphism level in three spelt wheat cultivars - Hercule, Altgold and Rouquin, three new-breeders' spelt lines - H92.27, H92.28 and M92.20 (originated from hybridisation between spelt and common wheat) and reference common wheat cultivar Brea. Electrophoretic phenotypes and zymograms were evaluated by means of digital image analysis and Nei and Li coefficient of similarity was used to evaluate the relation of analysed genotypes. Entire evaluation of all four-marker systems showed differences between common wheat cultivarBreaand spelt cultivars and spelt breeders' lines. Also significant differences between old spelt cultivars (Hercule, Altgold and Rouquin) and new spelt breeders' lines were found. The reality of the mutual passing of protein fractions (gliadins and glutenins), based on Osborne extraction was confirmed. In this sense it is necessary to see both fractions as dynamic overlapping structures.

Four kinds of cereal crops were grown without farmyard manure application. The effect of farmyard manure was supposed to be replaced by post-harvest residues (PH treatment) or by ploughing the total by-product, i.e. straw (PZ treatment) into soil. After seven years of application, this soil farming system did not influence the contents of Cox and Nt in soil. The amount of organic carbon had declined after the first year, but in the following years it remained at the same level (1.2%). The total nitrogen content increased from 0.143 to 0.166% without any considerable difference between the treatments. The amount of microbial biomass (C_mic) in PH treatment had been varying and in 2000 it decreased approximately by a half (from 215.96 to 132.00 mg C/kg of soil dry matter). The input of organic matter due to ploughing the whole by-product (PZ treatment) into soil acted favourably and the value of C_mic in 2000 was quite comparable with the average values of the individual years of 1994-1997. This land management and cereal growing caused a reduction of the ratio of microbial biomass carbon to soil organic carbon (C_mic/C_org). In the year 2000, the values decreased from 2.59 to 1.09% and from 2.88 to 1.82% in PH and PZ treatments, respectively. The amount of the biologically releasable nitrogen (Nbiol) and the intensity of nitrification were the highest in the year 2000. There was a moderate negative correlation (r = -0.474) between the N_biol values and biomass amount values in PZ treatment, and a very close negative one (r = -0.972) in PH treatment. This relation became strong in both treatments when the values Cmic/Corg and Nbiol were compared, i.e. r_PH = -0.863 and r_PZ = -0.921. The results confirmed that the amount and the quality of organic matter influence microbial biomass and its activity which is responsible for the nutrient release.

Biological and chemical (fertilising, liming) amelioration are among the principal tools used to restore degraded sites. These techniques were also used on the Ore Mts. plateau on plots prepared by bulldozing. We evaluated the impact of these amelioration techniques by measuring tree species primary production and humus form restoration. Begun in 1983-1985, this project studied growth reaction of forest stands by measuring height and diameter increment, for the following species (blue spruce Picea pungens Engelm., European larch Larix decidua Mill., lodgepole pine Pinus contorta Dougl., Eastern white pine Pinus strobus L., alder Alnus incana Moench., European beech Fagus sylvatica L.) during the period 1994-2000. The growth potential by species decreases in the following order: larch, alder, lodgepole pine, white pine, blue spruce. Beech was almost exterminated by red deer browsing and the harsh climate; pines suffered heavily from browsing and bark stripping. Holorganic horizons were measured and basic soil chemical and mechanical characteristics were determined - pH, soil adsorption complex characteristics (using Kappen's methodology), content of the humus and total nitrogen, exchangeable acidity and plant available macronutrients, granulometric composition of mineral soil horizons. Our results confirmed the relatively long-lasting effects of soil amendments, as well as the amelioration effects of alder, and the relatively inhibiting effects of larch and blue spruce.

Models evaluating static stability (resistance to breaking or uprooting of trees caused by wind, snow or ice) of forest stands in the seventh altitudinal vegetation zone were determined. The empirical material came from 180 research plots (High Tatra and Low Tatra Mountains) established within the research project Research on methods for mountain forest management based on sustainable Development. Static stability was characterized by the slenderness ratio that was calculated from the mean height and diameter of target trees. Then the particular forest stands were categorized with regard to slenderness ratio, mean diameter and absolute site class using either tables or graphic models. Particularly, four static stability classes were made up: 1 - very good, 2 - good, 3 - sufficient, and 4 - insufficient. Practical application of the models is shown for forest stands grown in the area of Vajsková and Lomnistá valleys.

The objective of the trial in the test station was to evaluate productive performance with respect to sire-line No. 101, 102, 103 in C-position for LWs × (LW×L) genotype in pigs. The productive performance as to growth capacity, feeding intake and quantitative traits of slaughter value was examinated for 136 hybrid pigs divided in three groups of offsprings of LWs boar No.101, 102,103. The feeding of all pigs were ad-libitum. On the base of obtained results, one could say that inside the LWs-breed, considerable differences exist between lines, importantly affecting the overall economics of fattening.

In all partial aspects, subsidies can be effectively realised only if the adequate system of information is set up and used both on the level of subsidy suppliers (government) and on the level of subsidy recipients (agricultural organisations). It is essential to control and evaluate the usefulness of providing the support. The GPS technologies are ones of many options how to contribute to this effort. The proceeding rapid progress and upgrade of these technologies, miniaturisation of the apparatus along with the decreasing price and increasing technological efficiency, accuracy and reliability are together granting significant preconditions for their practical utilisation in agriculture. GPS is practically being used in agriculture in the system of precise agriculture and our experts belong among the world-wide recognized specialists in this direction. The GPS utilisation is additionally offered at the allocation of LFAs as well as at marking the places suitable for agro-environmental measures. In combination with the IACS system and its databases and registers, it is functionally and operatively useful at the land control of fulfilling the conditions of support programmes.

Dependently on planting conditions caraway fruits contain 1-9% of essential oils consisting of about 30 compounds. Carvone and limonene account for the main portion, about 95%. To evaluate the quality of various registered caraway (Carum carvi L.) cultivars (Kepron, Prochan and Rekord) planted during 1998-2000, regarding the effect of sample grinding and preparation, plant treatment and time of harvest, the amounts of essential oil and the carvone/limonene ratio were determined. Both whole and ground caraway seeds were extracted. As obvious from the results, SFE is not suitable for the determination of essential oils in whole seeds since the results are lower in comparison with those of ground caraway. The way of grinding was also examined. Of the three mills used, a splintery mill VIPO seemed to be the most suitable. Further, the amount of essential oil was studied in caraway gathered at the beginning of maturation (sample A) and at full ripeness (sample B) of caraway seeds. It was found that the samples gathered at full ripeness (samples B) had more essential oil. It was also concluded that the use of the regulator Roundup Bioaktiv during caraway maturation to unite the ripening of achenes in the main umbel and the first-order umbels, and the use of fungicides (Alert S and Prelude 10) affected positively the amount of essential oil in caraway. Possibilities of SFE application for the essential oil determination in small samples gathered during breeding were investigated. The results were used as a one of the criteria during breeding. Classical way of the essential oil determination does not allow this option. An alternative method for the isolation and determination of essential oils - supercritical fluid extraction (SFE) - was investigated in this study.

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.

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).

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

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.

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.

Due to the transformation of the agricultural subjects realized after 1990, the new ownership relations occurred in the sectors of agriculture and food processing. The entrepreneurs started to build their activities on the base of market economy principles. The farmers started founding of specialized or universal-trading organizations aimed to sale of the agricultural production. The legal forms of the companies were cooperatives or companies incorporated. In practice, the subjects proved the reasonability of their existence not only on the side of agricultural production sale, but also on the side of purchasing inputs necessary for the agricultural production process. One of the best trading organizations is Agropork-družstvo in Brno, which is specialized in purchasing and sale of pigs, cows and recently poultry as well.

The development of rural areas is solved by the regional policy from a great part. Since every country implicating and applying this support system is identified by its geographical and political specifics, many problems rise also in the Czech Republic and they complicate the implementation of the regional policy principles in the final result. The possibility of improving this situation is given through identification of the relevant problems and the realization suggested actions. The problem areas in rural municipalities development requiring solution are as follows: poor transport services, non-existing cooperation inside the transport and mutual losses compensation, poor technical equipment of municipalities, securing a constant support of rural development, establishing functioning ties to the community center areas in the micro- regions, establishment of foundations, decomposition of rural development aims, public administration. Respecting of the proposed solution areas in municipalities would help to decrease regional disparities in rural areas.