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We evaluated the need for low temperatures (vernalization) and the photoperiodic reaction of three collections of winter oats (1. Pedarn, Maris Quest, Peniarth; 2. Gerald, Solva, Kymon, Pendragon; 3. Pewi, Silwi, Wiskas) in a comparison with spring oats varieties. All three collections of varieties showed little need for low temperatures, mostly as few as 10-20 days, which does not represent an obligatory need; this influence is only quantitative and constitutes no precondition for a passage of plants into the generative stage. Only in the case of the Maris Quest variety, the need for vernalization approached 30 days. As compared with the reaction of winter barley varieties that had and in some cases still have worse overwintering in the Czech Republic, the length of vernalization is equal. In the photoperiodic experiment, the reaction to a short autumn day turned out to be the critical condition for a possibility of autumn sowing and overwintering; in the case of these varieties, a short day inhibits the development until arrival of winter. We evaluated this reaction according to the length of the induction period. This period was only 10-15 days in the case of the spring oats Český žlutý, 30 days in the case of winter oats Maris Quest, 25 days for Pedarn, 20 days for Peniarth and 21 days for Pendra-gon; the induction period was 14-21 days in the case of varieties Gerald, Kymon and Solva. When compared with figures for winter barley, it had the longer photoperiodic induction period. The evaluated varieties of winter oats do not reach such a degree of a reaction to a short day, which manifests itself in their lower frosthardiness than that of winter barley. We verified that in provoking tests for frosthardiness, and also by lower critical values of temperatures for dying out of 50% of plants, the so-called LT 50.

A morphometric study of Amaranthus cruentus, A. retroflexus and their hybrid, A. × turicensis based on 75 plant samples (750 inflorescences), collected throughout the Olomouc-Holice area (Czech Republic), is presented. Using multivariete methods (including cluster analysis and canonical discriminant analysis), the existence of three groupings of plants was proven. The hybrid exhibited intermediate values of the width and length of female tepals, length of awl-shaped bracts, and seed size when compared with parental species. A germination experiment showed that dark seeds of A. × turicensis as well as dark seeds of A. retroflexus germinate scarcely and independently on the day length while light seeds of A. cruentus germinate promptly and markedly better under a short day regime. The chromosome analysis showed that A. retroflexus, A. cruentus, and A. × turicensis have the same chromosome number 34.

Two methods were developed and tested for the measurement of the mowing machine material feed rate (based on the conditioner power input measured by a torque-meter, and/or on the material change in momentum measured by a curved impact plate). The measurements carried out in the year 2001 proved that a very good linear relationship existed between the conditioner power input, output frequency of the apparatus measuring the impact force by means of the impact plate, and the material feed rate through the mowing machine. The calculated R-Squared values were about 0.95. In the year 2002, the impacts of material and condition (parameters) changes on the mowing machine material feed rate measurement accuracy were measured under laboratory conditions. It was evident from the statistical evaluation that changing crop variety, crop maturity, and intensity of conditioning can have a statistically significant influence on the measurement based on the torque-meter. As concerns the impact plate measurement, it was found that it is not possible on the basis of our measurements to determine statistically the influence of the factors tested.

Extensive forest areas were ameliorated by large-scale liming in the last years in order to prevent proceeding acidification and degradation of forest soils. The hitherto knowledge of liming effects on the function of forest soils still appears insufficient for an unambiguous evaluation. Sorption properties of soils and acidity are favourably affected by liming and the favourable effect is usually manifested in the layer of forest floor humus and in mineral soil within ten years. Reduction of soil acidity stimulates development of a bacterial component of microflora, soil edaphon, and good prerequisites are formed for a release of nutrients from soil organic matter. Improvement of some physical parameters of soils and negative effect of liming on the depth of rooting in spruce, availability of nutrients at some sites and in connection with mechanical soil preparation were also described. A key point of liming effect on forest soils is nitrogen dynamics. Mineralization of nitrogen is stimulated at nitrogen-rich sites with C/N < 30. Nitrogen-limited sites show nitrogen mineralization inhibited by liming with signs of pronounced deficiency in spruce nutrition. A positive effect of liming on nutrition with bases is generally accompanied by an adverse influence on N dynamics in acidic soils under spruce monocultures. Therefore it is possible to state that liming induces relatively marked changes in the soil but the actual growth response of woody species cannot be derived only from these changes.

The article deals with the comparison and evaluation of the development of economic indicators, such as the costs, yields, economic result and profitability in the Czech and Slovak Republics for the period of years 1997-2000. The economic indicators are evaluated and compared on the basis of sample survey results of the RIAFE Bratislava and RIAE (Research Institute of Agricultural Economics) Prague. The first part contains the evaluation and comparison of the costs, yields and the economic results for agricultural production and its branches recalculated per 1 ha of agricultural land (a. l.). The second part contains the evaluation and comparison of the production intensity indicators (per hectare yields, utility), costs per 1 ha, 100 feeding days and per unit, and agricultural production realization prices. Based on these indicators, cost profitability of the selected plant and animal products is quantified.

The paper analyses the pay system in a particular enterprise in the Czech Republic and proposes a change in this system. The establishment of two scales based on pay classes per month is proposed: one scale that allows for overlaps of pay classes but does not allow for overruns into other categories, and another scale that allows for no overlaps at all.

The effect of droplet spectra on efficiency of contact and systemic herbicides was evaluated. As a model components were used: mixture of clethodim 240 g/l + surfactant (90% raps fluid, 10% polyetoxyl esters); bentazon 600 g/l and bentazon 480 g/l + Wettol LF 150 g/l. The effect of droplet spectra on Elytrigia repens (L.) Desv. was evaluated using systemic herbicide (clethodim 240 g/l + surfactant). No significant differences of the efficiency were observed between different droplet sizes at the treatments of mixture of clethodim + adjuvant between very different droplet size ranging from VMD = 193 µm to VMD = 929 µm. The effect of droplet spectra on Chenopodium album L. and Galium aparine L. was evaluated using contact herbicides (bentazon 600 g/l and bentazon 480 g/l + Wettol LF 150 g/l). Six droplet spectra, ranging from VMD = 183 µm to VMD = 911 µm, were used. The efficiency significantly increased with smaller droplet sizes. The worst results were achieved by droplet spectra of 586 µm and 911 µm for both bentazon 600 g/l and bentazon 480 g/l + Wettol LF 150 g/l. Effect of droplet spectra is more pronounced in contact compounds. Translocation of systemic compounds may be the main mechanism that nullifies the effect of the droplets size and lower leaf coverage.

Activities on plant genetic resources in the Czech Republic are concentrated in the National Programme on Conservation and Utilisation of Plant Genetic Resources. Eleven institutions maintain 51,000 accessions, of which 17.3% belong to vegetatively propagated species. Research Institute of Crop Production (RICP) Prague has the responsibility for the coordination of the Programme; it holds more than half of all accessions in collections of genetic resources, runs the national information system and provides long-term storage for all seed-propagated species. All Czech collections are fully documented in passport data. Evaluation data (based on National descriptor lists for 29 crops) are available for 33% of the accessions. Much work is currently spent to the description and evaluation of collections, to facilitate their utilisation in breeding and agricultural practice. Also collecting missions on the Czech territory, conservation and monitoring of valuable resources maintained in situ contributeto the maintenance and evaluation of local resources. Landraces are considered a valuable part of the collections. Suitable ways of "on farm" conservation are investigated for selected accessions, to support their utilisation in agricultural practice and to enrich the existing diversity of crops and cultivars. Cultivars and landraces of neglected crops (buckwheat, millet, hulled wheat species) were successfully used to enrich the agro-biodiversity and for specific purposes of human nutrition. Close collaboration with producers (often organic farms) and processing industry has been established. Selected alternative crops and catch crops were studied as potential new crops.

Root growth inhibition and loss of cell viability in barley root cells were induced by Al during germination of barley caryopses on filter paper moistened with 2mM AlCl3. The inhibition of root growth as well as loss of cell viability started on the third day of germination. This time was also needed for induction of Al-induced changes in the composition of cell wall proteins. The accumulation of three salt-extractable polypeptides with relative molecular mass 14, 27, and 29 kDa started 72 h after the beginning of germination of barley caryopses on Al containing filter paper. However, the inhibition of developmentally regulated deposition of three (18, 23 and 28 kDa) salt-extractable CW polypeptides was observed at the same time. The pattern of detergent-extractable CW proteins was not influenced by Al regardless of the duration of Al treatment.

The yield potential, quality and level of resistance to powdery mildew (Erysiphe pisi DC.) of afila smooth seeded pea (Pisum sativum L.) were tested in the field trials. The cultivars and breeding lines Mozart, Consort-R, AGT-01, Cebeco 1171 and AGT-GH surpassed the control cv. Gotik in the yields of dry seed, in contrast the dry seed yields of Highlight, AGT-KR, Melfort and LU 390-R2 were about 12-27% lower than that of the control. The low seed yield was caused by virus infections (PEMV, BYMV), root diseases (Pythium, Fusarium), and a low level of thousand seeds weight (TSW). Material crossing with donors possessing high yield potential, a higher TSW, and a higher tolerance to root diseases had a positive effect on the dry seed yield. The main objective of the resistant pea breeding programme is afila smooth seeded pea resistant to powdery mildew, with a high tolerance to viruses, root diseases, and lodging, with the stem length of 60 to75 cm, and with high yield potential.

We examined the impacts of variation in overstory structure and burning regime on understory vegetation in the longleaf pine (Pinus palustris Mill.) forest of the Okefenokee National Wildlife Refuge in southeastern Georgia, U.S.A. On sandy upland sites surrounding the Okefenokee Swamp and on islands, we established five randomly-located 0.04-ha plots within each of six study areas. The plots varied in overstory density, past management and fire regime. We measured overstory tree size of longleaf pines in the 0.04-ha plots and percent cover of ground cover species in five 1-m2 subplots nested within each 0.04-ha plot. We also calculated diversity indices for the ground cover species. There was no significant relationship between overstory basal area and any diversity measure. Even at the subplot level, there was no significant relationship observed between the diversity measures and distance to the nearest tree, presumably a surrogate for overstory density. The diameter (DBH) of the nearest tree exhibited a slight influence over the Shannon Index, and the nearest tree's height was significantly related to evenness in each subplot. There were varied relationships between individual species and fire regime or nearest tree measurements. There was a definite, but statistically insignificant, trend of decreasing diversity with increasing years since the last burn. Height of the nearest tree positively influen­ced evenness, probably reflecting the influence of stochasticity and amount of needle deposition (influencing fire behavior) over a wide area. Within the generally equal fire-return interval across sites, individual fire-events and site-specific behavior apparently influence understory diversity. It is not surprising that the last burn would affect species richness, even more so than the number of growing-season burns, other studies support this observation. The presence of obligate seeding and (clonal) sprouting as dominants in the ground cover suggests that the fire-return interval is not regular. The cycling of fire-return intervals, even within the manage­ment-prescribed 2- to 4-year range, and the variation by microsite appear to provide sufficient variability of disturbance to create diversity in the ground-level cohort. Site-specific relationships between particular species and the nearest tree suggest that even a narrowly-prescribed fire management regime can provide sufficient diversity.

In Hungary, after the political and economical transition period of the nineties, the transformation of agriculture, the privatisation and the partial compensation brought about fundamental change in the land ownership structure. Recently, the private ownership of land has become dominant. As a result of the land compensation and the restoration of individual shares of the co-operatives members, unfavourable farm structures were established in a great number of cases; and consequently the redistribution of land property has become indispensable. The revival of the market is hold up, on one hand, by the present legislation of land acquisition (by Hungarian legal entities and foreigners) and, on the other hand, by the repugnance of the land acquisition of foreigners by a great number of people. The political risks, the EU accession and the changes to be expected concerning the EU subsidy schemes might also affect the land market in the long-term.

The main idea of the paper is to evaluate the state and development of financial structure of selected agricultural co-operatives in accounting periods from 1994 till 2001. Assets financial stability constitutes an ability of an enterprise to create and balance an accurate relation between assets and their financial sources. The results of the research work document a positive tendency in financial structure in favour of equity capital (Table 1). On the other hand, there have been problems with borrowed capital mainly with the liabilities from business relation. An increasing level of earnings can be assessed positively as well as the participation of new loans in the financial basis of enterprises (Table 3).

Entomopathogenic and mycoparasitic fungi were characterised by RAPD technique, with special attention to evaluate the genetic stability of strains that are used as active ingredients in commercial biopesticides. Strain-specific fingerprints were constructed for Paecilomyces fumosoroseus - strain PFR 97 Apopka, Gliocladium virens - strain GL 21 and Verticillium lecanii - strain MYCOTAL. Genetic stability and homogeneity was confirmed among re-isolates that were obtained from commercial batches of bio-insecticide PFR 97TM 20%WDG and bio-fungicide SoilGardTM12G that had been produced in 1995-1999. RAPD analysis indicated the genetic identity of V. lecanii strains re-isolated from the two different bio-insecticides MYCOTAL^® and VERTALEC^®. The usefulness of RAPD technique was demonstrated when P. fumosoroseus strain PFR 97 Apopka was reliably identified after having passed through adults of the spruce bark beetle Ips typographus, and by analysis of the relationship between fungi of the genus Gliocladium.

The influence of different fertilizer forms and rates on nitrogen, phosphorus and potassium contents, nitrate accumulation and yield in red head chicory (Cichorium intybus var. foliosum L.) was investigated. Field fertilization trials were set up at two localities inNorthwest Croatia in 1999 and 2000. Trials were laid out according to the Latin square scheme in five fertilization treatments: manure 5 kg/m2, three rates of complex mineral fertilizer NPK (5:20:30) - 50, 100 and 150 g/m2, and an unfertilized control variant. The results of investigations indicate that there were no significant differences between treatments in the plant nitrogen and phosphorus contents. Significant fluctuations of the chicory potassium content (3.27-4.75% K) depending on the fertilization variant were recorded only in 1999 while in 2000 all values (4.13-5.12% K) were uniform. Plant nitrate levels were influenced by weather conditions more significantly than by the form and rates of fertilizers. All the recorded values are within the limits tolerated for leafy vegetables. Comparing the trial years, yields were generally higher in 1999 (1.58-4.95 kg/m2) than in 2000 (0.40-2.70 kg/m2). No significant differences in yield were recorded between the application of stable manure and the lowest mineral fertilizer rate.

The observations were conducted on chernozem soil in a sugar-beet production region in 1971-2002. Six variants of organic amendment were examined: l - straw harvest, 2 - straw harvest + green manuring, 3 - straw incorporation, 4 - straw incorporation + green manuring, 5 - straw burning, 6 - straw burning till 1977 + intercrop, incorporation of farmyard manure at 10 t/ha since 1978. The effect of organic amendment on winter wheat continuous cropping was statistically significant. On average of the whole period (32 years), the highest yields were produced in variants with straw burning (var. 5) - 6.04 t/ha and with green manuring (var. 2) - 6.03 t/ha, and lower yields in variants with straw incorporation into soil (var. 3) - 5.65 t/ha, (var. 4) - 5.67 t/ha. The smallest differences between variants were found in the first decade of the experiment. Over time (in the second and third decades), the differences increased and positive effects of green manuring and straw burning and adverse effects of straw incorporation into soil increased. The yield level of winter wheat continuous cropping was high under the given conditions. The yield for the whole period of the experiment averaged 5.85 t/ha, the yields 5.19, 6.54 and 5.76 t/ha were obtained in the first, second and third decade, respectively.

In the paper are presented results of grain outer quality loss investigation during its post-harvest treatment. Objective was to determine the grain damage during its transport by bucket elevators of type "SANFON" at bucket peripheral velocity 2.0 m/s and 2.8 m/sof capacity 40 t/hand 80 t/h, respectively. The damage was investigated at counter-flow and parallel-flow bucket filling. From the measured results resulted the conclusion, that the bucket elevators tend rather to grain crushing, i.e. fraction creation than to smaller damage. On basis of partial knowledge chain elevators have no significant tendency to fraction generation, but incline considerably to the transported grain total mechanical damage at performance significantly lower than is the nominal one. In that case total mechanical damage ranged from 1.78 to 1.98%. Auger conveyers tend rather to total mechanical damage of transported grain than to the fraction creation. This is caused mainly by the friction between the transported grain and transporting "trough". Total mechanical damage is in range from 1.36 to 1.73%. Belt elevators are friendly to transported grain and therefore are evitable for grain horizontal transport in lines for reception, treatment and storage of food grain crops.

The paper deals with problems of thinnings in a mixed stand (spruce-fir-beech) situated in the sixth altitudinal forest zone. Three of the five investigated plots were tended by free crown thinning for a long time, and two were left without any planned silvicultural treatments as control. Dynamic changes in tree species composition, stand structure, qualitative and quantitative production were evaluated for a period of 30 years. The changes were compared with respect to differences between the plot with long-term silvicultural treatments and the control plots (without treatments).

The applied skidding technology strongly influences the impact of harvest on the ecosystem and success of natural regeneration. The impact of skidder SLKT 81 and high-lead system Larix 3T on forest soil and natural regeneration was compared under analogical site and stand conditions in a production beech forest in the environs of Brno, Czech Republic. The skidder was found to have greater effects on the soil surface consistency, soil properties and natural regeneration than the high-lead system operations. Although high-lead system operations are more friendly to all parts of forest ecosystem, the skidder may not cause excessive damage when applied under suitable terrain and climatic conditions.

The transition to the CAP and admission to the internal market triggered a shock wave in Austria which caused fundamental changes in the country's farming and food industries. Behavioural patterns stuck in traditional routines and petrified structures began to break up. The resulting thrust towards modernisation has been a major success of the EU integration. Eastern enlargement, about to be embarked on by the European Union, will have a greater impact on Austrian agriculture than the country's accession to the EU ever had. Farmers will have to brace for a loss of market shares and an additional pressure to adjust. The rural regions bordering the accession candidates will be particularly hit and thus require special attention in terms of economic policy measures. Agriculture and rural regions in Eastern Europe will profit from the EU-membership.

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

In the experiment conducted in the greenhouse, the different doses of UV-B radiation applied to the two species Avena fatua and Setaria viridis induced changes in leaf and plant morphology. It was a decrease of plant height, fresh mass of leaves, shoots and roots as well as leaf area. Besides, it caused the leaf curling in both of the species. The significant differences between Avena fatua and Setaria viridis in the studied traits were mainly due to the tillering ability of the species. The content of chlorophyll varied considerably. The average values of leaf greenness (SPAD units) for oats were about 43 while for green foxtail 32, respectively. U-VB did not reduce leaf weight ratio, shoot dry matter, shoot to root ratio and leaf area ratio.

In vitro propagation of Tilia platyphyllos Scop. has been achieved by axillary shoot proliferation and somatic embryo-genesis. The influence of tree age, explant source, genotype, and phytohormones on micropropagation of juvenile and mature trees of Tilia platyphyllos has been investigated. Nodal segments and shoot tips were used as initial explants for axillary shoot proliferation. Low concentration of cytokinin (BA, BPA, TDZ) plus auxin (IBA) stimulated fast shoot multiplication. Microshootsexcised from proliferating cultures were rooted on low salt medium and produced trees were planted in the field. Embryo-genic tissues were initiated from zygotic embryos cultured on MS medium supplemented with 2,4-D. After transfer of embryogenic tissues with developing embryoids on media lacking 2,4-D and supplemented with low concetration of IBA, the development of somatic embryos was enhanced. Secondary somatic embryogenesis led to the formation of new adventive somatic embryos. Trees produced from somatic embryos were planted in the field and exhibited normal growth and morphology.

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

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

Rhizosphere and rhizoplane of fababean (Vicia faba), melochia (Corchorus olitorius), sesame (Sesamum indicum) and soyabean (Glycine max) plants are inhabited with fungi, mostly Aspergillus flavus, A. niger, Fusarium oxysporum, Penicillium corylophilum, P. cyclopium, P. funiculosum and Rhizopus stolonifer. All fungal species have the ability to produce gibberellin (GA) but F. oxysporum was found to produce both GA and indole-acetic acid (IAA). The optimum period for GA and IAA production by F. oxysporum was 10 days in the mycelium and 15 days in the filtrate at 28°C. The contents of GA and IAA were significantly increased at 0.5 and 1% NaCl after 5 days, but they were lowered at 4% (700 mM) NaCl. Cytochrome P-450 was significantly increased under salt stress at 0.5-7% NaCl. Calcium decreased NaCl stress on F. oxysporum by significant elevating GA biosynthesis at 40 mM Ca²⁺/700 mM Na⁺. GA at 10 µM and Ca²⁺ at 10 mM enhanced the germination of seeds under 175 mM Na⁺.

Change in the community of epigeal spiders and harvestmen (Araneae, Opiliones) was studied in an experimental apple orchard for six consecutive years. Five plots were surveyed by pitfall traps. Four of the plots were young (1-4 years); one plot was older (15-20 years). The abundance of epigeal arachnids increased with the age on the young plots, while it was constant on the older plot. There were significantly more arachnids on the young plots than on the older one. In turn, the diversity was significantly lower on the young than on the older plots. Lycosidae, Phalangiidae and Tetra-gnathidae dominated the young plots. The older plots were richer in Agelenidae, Clubionidae, Dysderidae, Gnaphosidae, Linyphiidae, Pisauridae and Salticidae. Principal species of the young and older plots were identified using multivariate analysis.

Achievements and prospects of wheat breeding for disease resistance in the world and in the Czech Republic are reviewed. Attention is paid to rusts, powdery mildew, leaf blotch, glume blotch, tan spot, fusarium head blight, common and dwarf bunt, eyespot, barley yellow dwarf virus on wheat and wheat dwarf virus. Genes for resistance to rusts and powdery mildew in the cultivars registered in the Czech Republic are listed. Promising resistance genes and sources of resistance to the above mentioned diseases are reviewed. Prospects of resistance breeding including application of methods of molecular genetics and development of synthetic hexaploids are outlined.