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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.

Surveillance on cyst nematodes in Slovenia started already in 1963. We have found Globodera rostochiensis for the first time in 1971 and for the second time in 1975 (two cysts). In 1999 cysts of yellow potato cyst nematode were found again. A small hot spot was detected along the Slovene Austrian border. Cysts of Globodera rostochiensis were extracted from samples taken in 1.6 hectare field. In 2001 we surveyed 194 fields with the surface of 468.29 ha. We discovered another hot spot of Globodera rostochiensis in the Central Slovenia. Cysts of Globodera achilleae are seldom discovered in Slovenia. During the period between 1980 and 2000 we extracted altogether 206 cysts. In 2001 we found three fields where we extracted at first seven cysts. With more detailed survey we extracted another 30 cysts. In a few soil samples taken from the imported potatoes from Italy we have intercepted cysts of Globodera pallida. For that reason shipments were returned. In a similar way in 2002 shipments from Croatia were returned because of G. rostochiensis presence. Specimens of Globodera rostochiensis and G. achilleae species found in Slovenia were morphometricaly handeled.

Arabidopsis thaliana accessions were inoculated with incompatible isolates of downy mildews, following pre-inoculation with compatible Albugo candida. Three isolates of Hyaloperonospora parasitica subsp. A. thaliana, an isolate of H. parasitica subsp. Brassica oleracea and one Bremia lactucae (lettuce) isolate were included. All downy mildews sporulated on A. thaliana, suggesting A. candida suppresses broad-spectrum downy mildew resistance. The white rust resistance gene, RAC5, is being investigated. The resistance phenotype associated with RAC5 seems not to involve a hypersensitive response. RAC5 has been mapped telomeric of nga106 on chromosome 5, in a region lacking NB-LRR genes, the most common structural class of resistance genes known in A. thaliana.

Microbial solubilization of hardly soluble mineral phosphates in soil is an important process in natural ecosystems and in agricultural soils. Regulation of the P-solubilizing activity by the presence of soluble phosphates in medium was determined. For this reason we decided to test a number of soil bacteria showing a high P-solubilizing activity for its sensitivity to the presence of soluble dihydrogen potassium phosphate in medium. At these studies, the direct determination of the solubilized phosphate in medium was masked by the presence of relatively high concentrations of soluble phosphate added. Therefore, we have modified the method, determining the residual tricalcium phosphate. The effect of soluble phosphate in medium on the P-solubilizing activity of rhizosphere isolates and strains of Rhizobium were tested in liquid cultures with the addition of various concentrations of soluble KH₂PO₄. The medium was filtered after incubation and the remaining tricalcium phosphate was separated by filtration. Filter papers with the remaining tricalcium phosphate were hydrolysed with 2N H2SO4. Phosphorus was determined spectrophotometrically. The P-solubilizing activity was expressed as a difference between the tricalcium phosphate added and its remainder after the incubation. These results fully confirmed that there exist the strains, whose P-solubilizing activity is inhibited and other strains, whose P-solubilizing activity is not inhibited or is inhibited very little in the presence of soluble phosphate. The use of our adapted method was much more suitable for this type of experiments.

Effect of temperature on growth and antagonistic ability of Trichoderma spp. isolated from local strawberry culture and commercial product, against Rhizoctonia solani, strawberry pathogen, was studied in vitro. Trials were carried out twice, at 10, 25 and 30°C. Inhibitor effect was evaluated by radial growth measures of established duals on PDA's dishes, using Royse and Ries formula, to evaluate the percentage inhibition of radial growth. Design of dishes was a randomized complete block, considering 10 replicates. Data were analyzed statistically by two-way analysis of variance. The objective has been to determine the most competitive Trichoderma strain and the best temperature that produce the inhibiting effect on the pathogen growth. Local strain has the best behavior at 10 and 25°C.

Both spring and winter barley were sown after a forecrop of winter rape. Three registered model varieties of six row and two row winter barley reached in the period 1999-2001 significantly higher yield than three model varieties of spring barley. Two row spring and winter varieties produced significantly higher thousand grain weight (TGW) than six row winter barley. The resistance to diseases and lodging (correlation coefficient with resistance to powdery mildew represent 0.68**, rust 0.72*, lodging 0.61**) was the most important factor determining the yield. Resistance to rust has influenced sieving on 2.5 mm, correlation coefficient reached value 0.88**. No significant differences were determined in any malting quality parameter when varieties of two row winter barley variety (Tiffany), and spring barley varieties (Akcent and Tolar) were compared. Variety Tolar reached higher parameters for friability and a beta glucan content. Between years, significant differences were found in following parameters: protein content and apparent degree of attenuation. Due to reduction of area sown with spring barley and reduced yield potential, two row winter barley varieties with comparable malting parameters are recommended to be cultivated as the reserve crop for malting barley industry demands.

The paper is focused on the evaluation of the possibilities of analysing the relations between economic and financial indicators of farm businesses by the application of multivariate statistical methods. It also indicates the possibilities of the construction of a general economic indicator of business effectiveness.

The foreign agri-food trade has showed an unsuitable development for the Slovak Republic during the 1999-2001s. The negative balance for the competitive commodities is increasing. These are the commodities for the production of which the SR has suitable natural conditions. The contribution deals with the selected competitive commodities in the kilogram prices. The study shows the decreasing tendency of kilogram prices in import and the increasing tendency in export. Higher export price is the consequence of the higher value added and thus also higher revenues.

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 results document changes in the herb vegetation of a South-Moravian floodplain forest in the period of 1978-1997. It is shown that hydrological measures strongly changed the floodplain forest in the area of the Dyje river near Lednice na Moravě. The herb vegetation in the area of the confluence of the Morava and the Dyje rivers was conserved nearly unchanged after artificial floods.

Natural regeneration is an important part of close-to-nature forestry. However, natural regeneration also has either natural or technological limits. Among the most important natural limits are a low sum of precipitation and site type. The study concentrates on Žatec region where the long term average sum of precipitation is only 440-450 mm per year. Dry periods during the vegetation time are quite frequent. The study was conducted on clear cut area, stand edge, shelterwood area and stand interior. The results showed the highest population densities in a shelterwood system, the lowest in the stand interior. On the other hand, the dry seedling biomass is lower for seedlings from shelterwood area than from clear cut area.

Counter immunoelectrophoresis (CIE) was used for the detection of species-specific muscle proteins in food products. This technique allowed the detection of pork, beef, poultry, or and kangaroo meats in heat-processed products at concentrations below 1.5%. CIE is based on the use of species-specific polyclonal antibodies prepared by immunisation of rabbits with heat-stable antigens extracted from visibly fat-free muscular tissue heated to 75°C, 100°C, or 120°C for 30 minutes. Adulterations in terms of declared product compositions were demonstrated by this method in 7 of the 50 tested commercial products.

In this study the aggressiveness of nine isolates of P. infestans was determined using detached leaflets from cultivars Bintje and Stirling. The growth of the isolates on the leaflets was recorded on a daily basis, for seven days, and an assessment of their aggressiveness could then be made. Extracellular preparations (ECPs) from the zoospore suspension of each isolate were used as a source of proteolytic activity. The ECPs were found to contain a level of serine protease activity using BTEE (N-Benzoyl-L-Tyrosine Ethyl Ester) as a substrate and recording the absorbance at 256 nm. The possible relationship between the serine protease activity and the aggressiveness of the isolate is discussed.

The localization of cysteine proteinase PLCP-2 was investigated in potato plants (Solanum tuberosum L.) cultivar Désirée by electron microscopy. Healthy and PVY^NTN infected potato plants were grown in vitro on media with or without a supplement of jasmonic acid. We had already shown that PLCP-2 is present in leaves, stems, tips of shoots and tips of roots of healthy and PVY^NTN infected plants. It was detected in various cell types in protein bodies in vacuoles, in cytoplasm and in cell walls. There were significantly larger amounts of PLCP-2 in plants grown on medium with a supplement of jasmonic acid in both healthy and virus infected plants. More protein bodies in vacuoles were found in plants grown on medium with addition of jasmonic acid.

Substitution lines with the chromosome 3B of the Czech alternative cultivar Česká Přesívka (CP) in the genetic background of the wheat cultivars Zdar, Vala, Košutka, Jara and Sandra, differing in their requirements of vernalisation and photoperiod, were compared with the original cultivars under short and long photoperiod, to evaluate the effects of genes, located on the chromosome 3B of CP, on earliness and the response to photoperiod and vernalisation. The results suggest that these genes have only a small effect upon the vernalisation requirement, but are more related to the response to photoperiod. However, the genes on the substituted chromosome appear to influence the earliness per se and very likely interact also with the photoperiodic response.

Chromosome 4A of Triticum macha carries resistance to Fusarium head blight (FHB). Double haploid lines (DH) of T. macha 4A were used to determine the type of resistance and location of the gene(s). FHB resistance and yield trait data collected over two seasons following spray and point inoculation, indicate that the resistance is of type I and is probably conferred by a single gene. The resistance was mapped with microsatellite markers to a small area of the T. macha 4A chromosome flanked by markers gwm 610 and gwm 165. This could greatly facilitate future marker assisted selection work aimed at increasing resistance to FHB in other winter wheat lines.

Field experiments were conducted in the maize-growing region on heavy gleic fluvisol from 1974 to 2000. Three variants of straw management (straw harvested, incorporated into soil and burned), two variants of soil tillage (conventional plough tillage to 0.22 m, shallow disc tillage to 0.12-0.15 m) and three variants of fertilization (30, 60 and 90 kg N.ha^-1) were studied. After conventional tillage, the highest yield was obtained in the variant with burned straw (5.50 t.ha^-1), followed by the variant with straw incorporated into soil (5.40 t.ha^-1) and the lowest after harvested straw (5.01 t.ha^-1). At shallow tillage, lower yields were assessed in all variants of straw management in comparison with conventional tillage (after straw burning 5.07 t.ha^-1, incorporation into soil 4.66 t.ha^-1 and harvest 4.54 t.ha^-1). The ranking of variants was identical to that in inversion tillage; however, the yield increased more after straw burning in comparison with its incorporation into soil. Yields increased regularly along with increasing rates of nitrogen. If long-term effects of straw incorporation on yields and yield trends were evaluated (in comparison with straw harvest), statistically significant decrease in yields was assessed after shallow in contrast with increase in yields after deeper straw incorporation.

Glucosinolates with Brassica genus as secondary metabolites have a lot of functions and effects. Glucosinolates form less than 2% of the overall sulphur content at the beginning of vegetation in different parts of the plants and during growth their content is decreasing and forms less than 0.1%. This low representation doubts their storage function. With its chemical composition, they are ranked among natural pesticides with active and passive resistance against diseases and pests. They show repellent effects and properties of natural biofumigators in soil after ploughing in their biomass as green fertilizing, or after ploughing in after harvest the leftovers of rape. The principle of these effects is decomposition products of glucosinolates - bioactive isothiocyanates. Very important from this point of view are turnip rape Rex and Brassica juncea, whose content of these compounds is the highest one and they are resistant against the attack of Ceutorrhynchus pleurostigma. The same effect showed also when attacked by Phoma lingam. With other winter Brassicas either hybrid or linea and summer rape is this defensive system suppressed because of their lowered content due to breeding interferences, leading to limitation of their anti-nutritional negative effects. It is possible to state the final result after finding out the production of the above matter, roots, and after evaluation of the sorbal characteristics of the soil and evaluation of the state of health of the following crop or vegetable. After this overall analysis, it will be possible to evaluate the biofumigation properties of accessible varieties of the Brassica genus.

The efficiency of the application of organic and inorganic additives on the reduction of mobility and transfer of As, Cd, Pb and Zn from the soil into the plants was observed. The dung, compost, acid peat and muck presented organic additives. Synthetic zeolite - type Pc of cubic structure, loamy shale and dolomite limestone presented inorganic additives. Five soil types were used during the testing (arenic regosol, typic cambisol, dystric cambisol, typic chernozem and typic fluvisol). The changeover of the mobility of As, Cd, Pb a Zn in the soil (the ratio of mobile and total contents, sequential analysis) and the transfer of the elements from the soil into the plants (the vegetables, cereals and fodder plants) were investigated. The results showed the primary importance of the soil pH value on the behaviour of potentially toxic elements and their intake by the plants. The efficiency of the use of organic additives strongly depended on the quality of the organic matter. Inorganic additives on the base of the sorbents worked in the case of mobile hazardous elements (Cd, Zn). The efficiency of the soil additives was strongly influenced by the soil type.

The old debt problem resulting from the transformation of the agricultural co-operatives of the former GDR (German Democratic Republic) is described with respect to its evolution and its economic policy treatment during the process of transformation. So far, the measures for the treatment of old debts have had business economically stabilising effects. Nevertheless, debts are still growing. The farms which are affected by such old debts are strongly interested in solving this problem. This explains the intensity of the results' discussion of a scientific expert opinion on an analysis of the mode of action of the old debt regulation in agriculture. The conclusions which can be drawn from the public discussion of these results with respect to the future treatment of these old debts show, that the affected farms favour a kind of bonus rule for debt repayment. Such a regulation also seems to be acceptable for the treasury as the final bearer of the remaining debts and as a solution to minimise the taxpayers' burden.

Environmental analysis in the winegrowing industry is necessary for strategic management of businesses in this industry. The paper is focused on PEST analysis and pays attention to individual factors. It emphasizes the necessity of adjustment of the Czech legislation to the EU conditions, fulfilment of its conditions, e.g. compulsory registration of vineyards. In the field of economics, it is necessary to pay attention to renovation of vineyards with the help of subsidies from the state budget because the industry contributes to keeping the cultural level of the region and the human resources on the territory. It can be also a source of the environmental pollution. The technology of vine processing follows the changes in viniculture, changes of growing-technology and of the structure of white and red varieties. In conditions of the Czech Republic, it means to gradually transfer to production of quality varieties of vines by gradual renovation, which has to be a priority. The winegrowing sector is the industry with the highest value added also in the Czech Republic, and its share in the total agricultural production in a region can reach a significant level.

Productivity and its stability were evaluated in a set of 24 apricot genotypes of the world collection and some promising new selections in 1994-1999. The productivity of most genotypes was higher than that of control variety Velkopavlovická LE-6/2. Genotypes with higher productivity in the years favorable for apricot productivity gave higher yields also in the years unfavorable for productivity. It was proved by a significantly close highly significant correlation (r = 0.64++). It is a reason for the necessary regulation of fruit set in highest-yielding varieties in the years favorable for apricot productivity when overproduction and undesirable reduction in the fruit size occur. The variability of yields in kg per tree, expressed by coefficients of variation over a six-year period, was high in the years of observation. The variability of yields was significantly lower in the years favorable for apricot productivity. To express yield variability the coefficient of variation and index of fluctuation can be used. Their similar conclusiveness was proved by the significant positive closeness of correlation between the values determined by both calculations (r = 0.51+). The varieties Vynoslivyj and Volšebnyj showed the highest and most stable productivity. From the producer's and breeder's aspects, of these two the Vynoslivyj variety is one of the most remarkable genotypes of the evaluated set due to its fruit quality and late ripening.

The optimization study was carried out in the part of the Jeseníky Mts. region in order to find the optimum variant of a forest road route. The ROADENG system was used for determining the Jezerná forest road design with use of projection above the digital elevation model of terrain. Particular variants of the forest road route were calculated and analyzed on the basis of environmental approach. The final report recommended one of the variants for the final elaboration of project documentation and for construction.

The post-eradication incidence of bovine tuberculosis in seven Central European Countries (Bosnia and Herzegovina, Croatia, Czech Republic, Hungary, Poland, Slovakia and Slovenia) was studied between 1990 and 1999. The majority of cattle to the age of 24 months were screened by tuberculin skin test on annual basis. Tuberculous lesions observed during meat inspection at abattoirs were further laboratory examined by direct microscopy, cultivation and histology for the presence of mycobacteria. Data describing the incidence of the disease in animals for the whole period were obtained from all countries except Bosnia and Herzegovina, where data were obtained after the year 1995. Between the years 1990 and 1999, bovine tuberculosis was diagnosed in a total of 1 084 cattle herds. Nine hundred and seventy five (89.9%) outbreaks of the disease were reported in small herds (10 cows) and 109 (10.1%) outbreaks in large cattle herds (>10 cows). The last outbreak of bovine tuberculosis in cattle was diagnosed in Slovakia, Slovenia, the Czech Republic, Croatia and Bosnia and Herzegovina in 1993, 1993, 1995, 1999 and 1999, respectively. Bovine tuberculosis was diagnosed under proper quarantine in Slovenia in 37 fattening bulls imported from two European countries before animals were introduced to the targeting farms.

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.

For 6 years the flight activity of pests on winter and spring oilseed rape was studied from spring till harvest, using yellow traps. In all years the flight intensity was higher in winter rape than in spring rape. The dominant insect pests of winter oilseed rape were Ceutorhynchus obstrictus, C. napi, C. pallidactylus, Dasineura brassicae, Meligethes aeneus, Phyllotreta atra and Ph. nigripes; subdominant were Athalia rosae, Brevicoryne brassicae and Psylliodes chrysocephala. In spring rape the dominant species were Brevicoryne brassicae, Ceutorhynchus obstrictus, Dasineura brassicae, Meligethes aeneus, Phyllotreta atra and Ph. nigripes; subdominant were Athalia rosae, Ceutorhynchus napi, C. pallidactylus and Psylliodes chrysocephala. Dasineura brassicae was not evaluated from trap catches. The damage by D. brassicae is higher to pods on axillary branches than on the main inflorescence. The occurrence of pests on spring rape was tied to a unsuitable phenophase of the plants at the time of flight activity and to the suitability of food. Winter rape requires a higher intensity of chemical treatment against pests than spring rape.

Wheat dwarf virus, a monogemini virus, infects several cereal species. Until now complete sequence data have been published only for wheat isolates. We cloned the complete DNA of 21 isolates from wheat, barley and Lolium spec. and compared the sequences with published data. Two types of the virus were found as previously described. Degree of entire nucleic acid homology between both isolates was in the range of 84%. The Large Intergenic Region showed most pronounced differences while the RepA gene was most conserved. No intermediate forms were found, though both isolates co-existed in the same hosts. Sequence data lead to the suggestion that they should be referred to as different viruses rather than strains of a virus.

Beet soilborne pomovirus (BSBV) was observed both in the sap and in tissues from local lesions on Chenopodium quinoa leaves after their embedding into acrylic resin LR White. Immunocapturing with polyclonal antibodies was used to enhance number of particles on grids and immunolabelling by colloidal gold was used for better visibility of virus particles in tissues. BSBV has rod-like particles of various length and it forms inclusions of several particles adhering side to side each to another.