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The study deals with the comparison of financial situation of farms in the Czech Republic. Three groups of farms are compared - co-operatives, business companies and individual farmers. The data were analysed within the years 1994 and 2000. The analysis of financial situation was done by the means of indexes describing liquidity, activity and profitability as well as some other additional indicators such as labour productivity and costs levels etc.

The resistance of six cultivars of winter oilseed rape (SL 509, SL 507, Darmor, Solida, Jet Neuf, Silesia) against Turnip yellow mosaic virus was studied. The number of over-wintering plants and plants with symptoms of TYMV infection were monitored. All plants were tested by the double diffusion test in agar and by DAS-ELISA to prove infection. ELISA was the most sensitive method, revealing 32-76% of latent virus infections in individual cultivars. The results clearly illustrated that monitoring of plant symptoms is not sufficient to prove TYMV infection in the field and that sensitive, large scale methods like ELISA must be employed to obtain reliable data.

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.

Several alterations of growth physiology and bulb formation in garlic (Allium sativum L.) crops, such as "rough" and "burst" bulbs, have been related by different authors with low temperatures during bulbs storage and crop development. These physiopathies affect both the yield and the quality of garlic crops. Incidence of such diseases in Spanish garlic (variety "purple of Las Pedroñeras") were studied during two consecutive years. Experimental design was factorial taking the bulb storage temperature (5°, 10°, 15° and 20°C) as variable factor. Growth indexes during crop development and final quantity of defective bulbs were evaluated. Experimental results show significant differences between treatments, with the higher incidence of both physiopathies in those bulbs stored at 5°C. The 15°C and 20°C storage temperatures clearly reduce the risk of these abiotic diseases and tend to increase the yield and the final quality of the crop.

Trace elements with a low mobility and with a low transfer are Cu, As, Be, V, Cr, Hg. Copper has at low mobility an increased transfer quotient (content plant/soil). The lowest mobility and transfer show Cr and Hg. Only at the very high contents or increased mobilities of trace elements, which accompany the anthropogenic contamination, soil critical loading for crops can be attained. Because of the amount of the examined extremes, it was not possible to derive the proper critical values. Therefore we were able to assess only critical protective values. They represent minimum total contents of trace elements or their mobile forms, which eliminate risks.

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.

A survey of development and prospects of the utilisation of doubled haploid techniques in rapeseed breeding in the world and in the Czech Republic is presented. The first utilisation of spontaneously occurred haploids from Brassica napus inbreeding programmes is described. The development of techniques of anther and later microspore culture is outlined. Special emphasis is given to the practical use of doubled haploids for the improvement of the effectiveness of breeding new productive cultivars. Some partial results of evaluation of yield parameters and resistance to important diseases in the obtained doubled haploid lines of winter oilseed rape are shown. The literary review and present results indicate, that the doubled haploid technique can be effectively used for the development of homozygous oilseed rape lines as an alternative to conventional methods.

Analytic measurement data acquired by an SFE/CGC analysis were compared with sensory evaluation of two wines from South Moravia. The sensory descriptive analysis showed a large variation in sensory quality from neutral character to full expression of the variety. Whereas the cluster analysis of volatiles was sufficient for differentiating both wines, the sensory observation data based on seven descriptors did not suffice either for bouquet or flavour characteristic. The descriptor citrus could be related to analytically established substances whose statistical significance was supported by a stepwise multiple analysis. The possibility of recognising vine cultivars via sensory descriptors is statistically feasible only by nutty and caramel descriptors in the case of bouquet and by big fruit for flavour.

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.

Ergot, caused by the fungus Claviceps purpurea (Fr.) Tul., belongs to the main constraints in seed production of Kentucky bluegrass (Poa pratensis L.). The level of ergot occurrence depends on the weather conditions during the growing period, harvest year, storage conditions of seed, and post-harvest treatment. The degree of resistance of the grown cultivar plays an important role. Based on greenhouse trials with four different ergot populations (Zubří, Czech Republic; Leutewitz and Munich, Germany; Pullman, Washington, USA) during 3 years, we found pathogenicity to be one of the most important factors. There were significant differences in the amount of ergot bodies formed between the Central European populations (Zubří, Leutewitz) and the American one from Washington State. The degree of pathogenicity has a major impact on the occurrence of ergot sclerotia in seed of Poa pratensis.

The genus Armillaria belongs to basidiomycetes and has been known to induce root rot disease and to cause extensive economic losses to a forest crop. We analysed about 40 isolates of Armillaria collected in Czech Republic by PCR and restriction analysis using gel electrophoresis and ion-exchange HPLC. Restrictase Hinf I was able to discriminate all investigated Armillaria species. The sensitivity and resolution of HPLC method was better than that performed by gel electrophoresis. HPLC was able to detect some heterozygous. The results prove the similarity of the species A. borealis, A. cepistipes, A. gallica, A. ostoyae in difference of A. mellea and A. tabescens.

Tan spot, caused by Pyrenophora tritici-repentis (Died.) Drechs., anamorph Drechslera tritici-repentis is one of the most important wheat diseases in the world, especially in the regions of intensive wheat growing. Tan spot had established for the first time in Latvia in 1994. Epidemic of this disease was observed in Latvia in 1998. Development of tan spot were investigated in field experiments at the Research and Training Farm "Peterlauki" of Latvia University of Agriculture in 1998-2001. Level of incidence and severity of tan spot differed depending on varieties and years. Severity of the disease was 16-71% in 1999; 0.1-5% in 2000 and 4-18% in 2001 depending on varieties at the time of ripening. 1999 summer was extremely dry, and development of disease was not observed. Explosion of disease was observed at the second half of June in 2000 and 2001, without reference to varieties. Date of increasing start differed, but in all cases important development was observed after flowering. Rate of increasing of disease was very high, during two weeks severity of disease increased from 0.1 till maximum of severity. Amount and frequency of rainy differed in 2000 and 2001, but increase on disease was very similar, it means, we need more information about favourable conditions for Drechslera tritici-repentis. Sexual stage Pyrenophora tritici-repentis was observed in Latvia for the first time. Further investigations are necessary, because relationships between meteorological conditions and stages of development are unclear.

In the framework of PVS eradication from breeding materials of Czech potato cultivars, the systematic research was devoted to: susceptibility of cultivars, occurrence of PVS in imported and domestic materials, and to maintenance of virus-free basic grades potatoes on breeding stations. In the field-exposure trials was proved high level of susceptibility of most cultivars to PVS and by contraries, gradualy increased proportion of maintained virus-free cultivars of foreign, as well as domestic origin. Nevertheless severe infestation still persist in some of them. The contemporary situation with maintenance of virus-free basic material in CR was demonstrated.

The effect of food products on temperatures reached in the microwave heating with and without susceptors was followed in experiments with certain types of food samples. A household microwave oven (650 W), susceptors from commercial packages for microwave popcorn, samples of two commercial pizza products and two types of dough were used in the experiments together with Luxtron temperature measurement system. The temperatures reached at the end of heating on the bottom surface of samples varied between 103 and 115°C at the heating without susceptor, and between 110 and 155°C at the heating with susceptor. Not only the susceptor but also the parameters of the heated samples (the moisture content, height/weight, the initial temperature) influenced the increase of the temperature on the bottom surface of the samples. The highest temperatures were found at the end of the heating of samples from dough with a lower content of moisture. The linear correlation between the temperature at the bottom of the sample and the logarithm of the time of heating (Zuckerman & Miltz 1995) was proved only with the heating of samples from one type of dough. The application of susceptor in the microwave heating alters not only the product temperature in the places of contact with susceptor but also - to a certain extent - in other places of the product. The change in the shape of the vertical temperature profile in the heated sample was found in the experiments with susceptor heating. For the optimal results of the heating with susceptor, the optimization of certain product parameters (namely the moisture content and the dimensions) have to be made

The research objective was to investigate the influence of different pipe drainage systems on the concentration and quantity of atrazine leached in drainage water, as well as in surface (0-30 cm) and sub-surface (30-60 cm) soil horizons in the production of agricultural crops on drained Gleyic Podzoluvisol. Investigations involved four different variants of drainpipe spacing (15, 20, 25 and 30 m, i.e. four variants in four repetitions). In a particular trial year, the same crop was grown and the same agricultural practices applied in all trial variants. Maize was grown in the first two trial years and wheat in the last year. Soil and water samples were qualitatively and quantitatively analysed for the presence of atrazine by gas chromatography. Atrazine concentrations in drainage water ranged from those within the limits tolerated for drinking water (out of the growing season) up to 458 ng.dm^-3. Maximum quantity of leached atrazine was recorded in 1998 (0.500 g.ha^-1), namely, from atrazine application in May 1997 to March 1998 incl., 0.630 g.ha^-1 or 0.052% of the initially added quantity was leached. Maximum atrazine concentration in the surface soil layer was recorded in traces or it was not recorded at all (0.013 mg.kg^-1), whereas no atrazine was recorded in the subsurface layer during the trial period. Analysis of variance produced no statistically significant difference in the atrazine concentration and leaching in drainage water and in the surface soil layer between different variants of pipe drainpipe spacing.

101 samples of faeces, colonic mucosa and rectal swabs taken from 100 pigs (29 commercial herds) were cultivated on Trypticase Soy Agar with 5% of sheep blood, spectinomycin (200 mg/l), vancomycin (50 mg/l), rifampicin (12.5 mg/l) and colistin (12.5 mg/l). Plates were incubated in an anaerobic container at 37°C for 5-7 days. 25 samples (10 faeces, 15 scrapings of colonic mucosa) were examined by darkfield microscopy for the presence of spirochaetes. In 80 samples (21 faeces, 31 rectal swabs, 28 scrapings of colonic mucosa) from diarrhoeic pigs 44 isolates of spirochaetes were identified by PCR method as Brachyspira hyodysenteriae. In 21 samples (20 rectal swabs, 1 scraping of colonic mucosa) taken from apparently healthy pigs in herds with swine dysentery were isolated weakly haemolytic spirochaetes: B. intermedia in 5 samples and phenotypic group III brachyspirae in 4 samples. Minimal inhibitory concentration (MIC) of tylosin, tiamulin and valnemulin was determined by the agar dilution method. To tylosin 16 out of 17 strains of B. hyodysenteriae were resistant (MIC 64 and 256 µg/l), one strain was susceptible (MIC l µg/ml). To tiamulin 17 out of 19 strains were susceptible (MIC from 0.016 to 0.25 µg/ml), one strain was intermediately susceptible (MIC 2 µg/ml) and one resistant (MIC 32 µg/ml). To valnemulin 17 out of 19 strains were susceptible (MIC from 0.016 to 0.064 µg/ml), one strain was intermediately susceptible (MIC2µg/ml) and one was resistant (MIC 8 µg/ml). Valnemulin resistant strain was also resistant to tiamulin.

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.

Phenomenalistic data of the development of prime costs in agriculture-oriented companies inSlovakia indicate that they have considerably increased in the main production, intracompany services and the company as a whole. Therefore, the management of a company has to apply an economic approach to cost management. Recommendations to build up a control structure of the cost system in the agricultural primary production are presented and its rational connection with actual costing, which uses algorithms of unconventional calculation methods, is analysed. In the cost system control structure, costs are recommended to be divided in two levels, namely by groups of activities and classification by elements of cost and by the relationship to outputs covering agricultural products. Using a general model, the objectives analysed are implemented in the livestock production aimed at dairy cow breeding.

On the basis of structure and qualitative parameters of agricultural soils, there are only 23.4% non profitable soils for the winter wheat growing in the total area of the Gemer Region. The same percentage for the corn maize growing is 78.7%, for the sugar beet growing 80.0% and for winter rape growing 46.0% of the total agricultural soils area in the mentioned region. Generally, for the crop production, it can be stated, that without production subsidies, at the present economic situation there are 65.9% soils non-profitable, 23.0% low profitable, 6.3% medium profitable and 4.8% high profitable in the Gemer Region. The calculated economic parameters can be used for a more effective production allocation and soil utilisation in different regions.

During 1996-2000 the secondary succession on a field left fallow was investigated. The experimental area was divided into a ploughed and an unploughed part. Both parts were divided into 5 × 5 m plots that were either left intact (control), mowed in June or July, or superficially cultivated in June. The position of the plots was identical each year. In successive years total dry matter production decreased in all experimental plots; in unploughed plots more than in ploughed ones. The spread of Cirsium arvense (L.) Scop. was increased by ploughing and superficial cultivation. Ploughing stimulated the spread of perennial dicotyledonous plants more than mowing in June and July. Superficial cultivation increased the spread of perennial dicotyledonous plants in the first years. Later on the proportion of perennial dicotyledonous plants decreased and after 5 years the plots were dominated by Anisantha sterilis (L.) Nevski. The incidence of Elytrigia repens (L.) Desv. was highest in the 5th year on unploughed control plots. The spread of perennial monocotyledonous plants was lowest in ploughed and superficially cultivated plots.

Application of the RAPD methods allowed to clearly characterization of isolates of Botrytis fabae and isolates of B. cinerea. Results from RAPD-PCR analysis indicate different groups. Clusters were related with groups based on conidial morphology, morphological characters of the isolates of Botrytis spp.

Apple cultivars were crossed according to the half-diallel and topcross mating design. Apple scab resistance of seedlings was estimated by using a 0-5 scale: 0 - no infection on leaves, 5 - more than 75% of leaf area infected. Percentage of scab resistant seedlings in crosses involving cultivars Prima varied from 35.8% to 67.6%, involving cultivars Florina and Arbat - 51.9-59.5% and 53.5-72.5%, respectively. Significant differences for resistance to scab were found among the crosses. Both general combining ability (GCA) and specific combining ability (SCA) were highly significant. The significance of GCA for scab resistance shows that genetic variability exists for this trait and selection should result in genetic progress, because the mean square for GCA was larger than that calculated for SCA. Therefore, selection of parents on its phenotype should be effective for development of resistant apple cultivars. The significant SCA estimates indicate that a large number of resistant seedlings from particular crosses should be selected.

The quality of eggs is tightly associated with freshness. New possibilities for the determination of egg freshness were studied. The volatile compounds of eggs and their changes during storage were followed. Three methods for extraction of volatiles were compared: dynamic headspace (Purge and Trap), static headspace (Solid Phase of Microextraction - SPME) and extraction according to Likens-Nickerson by simultaneous distillation-extraction (SDE) with diethyl ether as organic solvent. The extracts were analysed by GC/FID. The volatiles in an extract obtained by SDE method were identified by GC-MS. The extract includes aldehydes, alcohols, acids and esters. The volatiles in an extract obtained by SPME and Purge and Trap have not been identified until now. The changes in volatiles during storage of eggs using the above mentioned methods were studied.

The main goal of this work was to calibrate and evaluate the CERES-Barley and CERES-Wheat crop models. The experimental fields used for the model evaluation are situated in three different production regions (maize, sugar beet and potato main growing regions, respectively) with altitudes of 179, 204 and 560 meters above the sea level. Grain yield and date of anthesis together with maturity dates served as reference for the model evaluation. Two evaluation approaches were tested in this study. The first one uses historical data series and it is based on long-term field experiments with capability to reflect interannual weather variability. The second approach uses results of one-year multiple treatment experiment. The model evaluation is then based on a set of treatments differing e.g. in sowing date or an amount of used nitrogen fertilizer. Grain yields simulated by both models are acceptable when compared with experimental results: the coefficient of determination for historical series varied from 0.69 to 0.86 for evaluation of CERES-Barley at the three examined sites and reached values of 0.60 and 0.86 for the CERES-Wheat model at two experimental sites. The lower coefficient of determination of the wheat model was recorded at the locality with the highest altitude and coldest winter conditions. There, also the worst reliability of simulated phenological development was noted. At the second locality where the CERES-Wheat model was tested and at all three localities where CERES-Barley was applied, the simulated duration of vegetation period and anthesis dates were relatively accurate and yielded strong statistical correlation. The one-year multiple treatment experiment proved to be useful to determine the models sensitivity to differences in crop management. The combination of both approaches seems to be the best solution for evaluation of similar crop models if the detail long term experimental data are not available.

Field trials were conducted at two sites Troubsko near Brno and Prague-Ruzyně in 1996-1999 with three varieties of safflower (Gila, CW-74, Sironaria). Three rates of nitrogen fertilization were used: N0 = no fertilization, N₁ = 40 kg/ha, N₂ = 80 kg/ha. Sowing rates were 50 and 70 germinable seeds per m2. The average values of oil content were highest in seeds of CW-74 variety (27.2%). Gila had on average the lowest oil content (24.5%). Linoleic acid was dominant in all three safflower varieties. Variation in content of linoleic acid in different years was not so high as in oil content. The highest average content of linoleic acid was found in Gila variety (81.2%), the lowest in Sironaria (77.4%). At Ruzyně average seed yield on dry basis was 2.7 t/ha and average straw yield was 7.56 t/ha. At Troubsko seed yield was 2.56 t/ha and straw yield was 3.69 t/ha (by 50% lower than at Ruzyně). The effect of year of growing and site on seed yields and on other parameters was highly significant. N fertilization increased safflower seed yield at Troubsko site only, where the dose of 40 kg/ha N increased the yield by 0.08 t/ha on average of years and the dose of 80 kg/ha N increased the seed yield by 0.2 t/ha in comparison with no nitrogen fertilization treatments. Increased N rates and especially higher plant density resulted in an increase in straw yields. Neither were thousand seed weight nor number of flower heads influenced significantly by different N rates or the above-mentioned differences in plant density.

Partial characterization of iron binding compounds in spinach above ground biomass and differences between binding of Cd, Zn and Fe in spinach biomass were investigated on two soils treated by sewage sludge in model pot experiment. After application of sludge to both soils, Cd and Zn accumulation in spinach biomass was increased in sludge treatments. Total Fe content in biomass showed opposite trend with these treatments and was decreased 2.5-2.7 fold. Results of sequential analysis of spinach biomass showed lower portions of iron in all individual fractions of both sewage sludge treatments compared to control treatments. The largest differences in iron content between control and sludge treatments were determined in ethyl acetate fraction. While majorities of Cd and Zn were found in fractions methanol + H2O and H₂O and methanol + H₂O + HCl, iron content determined in these two fractions was only 7-8% in control treatments and 15-20% in sludge treatments of total iron. In fraction, Fe portion was 87.7-90.7% in treatments without sludge and 76.1-83.5% in sludge treatments in spinach biomass. Results showed tighter iron binding to plant cell membranes in contrast to cadmium and zinc.

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.

Agriculture is a traditional branch for the Republic of Bulgaria. The favourable agriclimatic and soil conditions further the growth of 145 agricultural crops and the production of various products, many of which have leading positions in the international market. The aim of this paper is to examine the nature and specific features of the reform of the land relationships in the Republic of Bulgaria during the period of transition towards market economy. The development of land relationships in this country reflects the economic interests of its society, which show their specific nature in the relationships between the owners and the leaseholders of the plots. It is typical for this country that during the collectivisation period, which took place in the middle of the last century, the land, being the basic production factor in the agricultural branch, was public property, the private character of which was never abolished. During the transition period, a process for restoring the land 'within its real borders' was started. This led to delay in the reform and a significant fragmentation of the land. The completed agricultural reform contributes to the recovery and precipitation in the process of developing of the land relationships in the country. A sign of this is the formation of land market. In the year 2001, 28 878.1 ha changed their owners, and another 280 000 ha were leased. The aim is, through active laws, to achieve synchrony of the social interests with the interests of the owners and leaseholders and to create conditions for optimisation of the production process in agriculture. A favourable economic environment will contribute to increasing the efficiency of the agricultural branch in the Republic of Bulgaria and to the formation of the land relationships, which will facilitate the process.