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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).

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.

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 objective of this study was an improvement on oat identification procedure for laboratory applications, and the comparison of albumin-globulin and avenin protein patterns in five hulled and naked oat cultivars: Abel (CZ) and Izák (CZ) - naked oats, Auron (CZ), Edmund (D) and Expander (D) - hulled oats. The last object of this study was the authenticity verification of standardly prepared meal samples with various proportions of admixture. It was confirmed that avenins, characterised under SDS-PAGE conditions, are reliable implements for the identification of oat cultivars. It was found that oat grain contains, on the basis of Osborne fractionation, another significant protein fraction - glutelins. The question of the protein fraction analysis that was used for the admixture identification stays still open. In sufficiently different cultivars, the certainty of the admixture detection in meal samples may be high. Nevertheless, in other cases (higher cultivar similarity) it will be necessary to use some other, more sensitive techniques.

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.

Caraway fruits contain 1-6% of essential oils consisting of about 30 compounds, from which carvone and limonene account form the main portion, about 95%. To evaluate the quality of various caraway cultivars, the amounts of essential oils and the carvone/limonene ratio were measured. The most common method of essential oil evaluation is steam distillation in accordance with Standard ČSN 58 0110, but an alternative method - supercritical fluid extraction (SFE) - was also investigated in this paper. Ground caraway fruits were extracted under different SFE conditions (pressure, temperature, use of modifiers). Released compounds (carvone and limonene) were quantified by GC.

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.

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.

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.

Traditional way of growing buckwheat (Fagopyrum esculentum L.) in Slovenia is stubble-crop production, but grown as a full-season crop it yields more. Genotypes that are adapted to stubble-crop system may not necessarily be the best adapted for the full-season crop. The objective of this study was to determine yield performance of two buckwheat genotypes under stubble-crop and full-season production system. The experiments (randomised block design) were conducted in Podravje region with two common determinant buckwheat genotypes (land race population and cultivar Darja) in 1997 and 1998. Buckwheat grown as a full-season crop had a greater leaf area index, more flower clusters, more developed seeds and 42% higher yield than the stubble-crop buckwheat. Although cultivar Darja had 10% less flower clusters than the land race population, the number of flowers and the number of developed grains were higher. The 35% higher grain yield of cultivar Darja was associated with larger leaf area index than land race population (4.0 vs. 2.3). Cultivar Darja outperformed the land race population under full-season crop production, whereas the yield difference between the two varieties was not significant under the stubble-crop production. These results suggest that the best yielding buckwheat genotypes should be determined separately for stubble-crop and/or full-season production system.

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.

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

The relationship between gliadin alleles, known to mark frost tolerance, and actual frost tolerance was investigated in 52 doubled haploids (DH) from the cross Florida× Vlada. Frost tolerance was expressed as percentage of plant winter survival in pots placed at different heights above the ground. Gliadin allelic blocks (GLI) were determined by starch electrophoresis. From the six GLI, known as frost tolerance markers, the GLI 1B1, GLI 1D5 or GLI 6D2 was present in 27, 27 or 31 DH, respectively. A weak, but significant correlation of r = 0.29 was found in the DH between their survival and frost tolerance prediction values based on the presence of the gliadin frost tolerance markers. The average survival of DH with gliadin frost tolerance marker GLI 1B1 or GLI 6D2, but not with GLI 1D5, was significantly higher than the survival of DH without this block. The DH without any gliadin frost tolerance marker had the lowest survival. Some gliadin genes thus can be used as frost tolerance markers for preliminary selection of frost tolerant lines and for the study of physiological and genetic constitution of frost tolerance in common wheat.

Specific productivity and some correlations between growth and productivity were evaluated in a set of 24 apricot (Prunus armeniaca L.) genotypes in 1994-1999. Even though the planting stock came from the same nursery, was of even age and on the same rootstock, the tree size of genotypes varied from planting to a permanent site. Differences in the tree size of genotypes slightly diminished over the six-year period, likely under the influence of uniform pruning used for all trees. Nevertheless, tree size evaluated from the area of stem cross-section can be considered as a genotype disposition. It is proved by a positive, highly significant correlation (r = 0.84⁺⁺) between the rank genotypes according to the area of stem cross-section in the fourth and eleventh year after planting. Confidence intervals also confirmed significance of differences in specific productivity. In total, specific productivity of twelve genotypes was significantly higher than in the control cultivar Velkopavlovická. A negative, significant moderate correlation (r = -0.40⁺) was calculated between tree size and specific productivity expressed as yield weight per unit area of stem cross-section. Weakly growing genotypes had higher specific productivity. The highest specific productivity was recorded in cultivars Vynoslivyj and Priusadebnyj and in LE-1321 and LE-390 hybrids. Of them, the most interesting for producers and fruit quality was Vynoslivyj with average fruit weight 47 g and harvest ripeness 11 days after Velkopavlovická.

The studies aimed at monitoring development of phagocytic and bactericidal activity in carps in the course of their ontogenetic development. The studies were performed using the techniques described by Mantur et al. (1986a, b), adapted to fish. Results were expressed in thrombocyte phagocytic index (Ipt), percentage of phagocyting thrombocytes (%tp), percentage of ingested bacteria (%bp) and in the index of intracellular killing by thrombocytes (Ibt). Number of thrombocytes was also examined using the technique of Dessi. Results of testing thrombocyte capacity to ingest the standard Staphylococcus aureus 209P strain showed that Ipt and %tp increased gradually in carps between the age of 3 and 17 months. In older carps, 19 to 29 months of age, as well as in spawners the growth in activity paralelled the ontogenetic development within Ipt values while %tp values remained at a similar level. Phagocytic activity of thrombocytes expressed in Ipt was reflected also by %bp values, which was particularly evident in fish aging 23 months to 5 years. In the case of Ibt, values of the index were not related in any way to stage of ontogeny or sex of the fish. Number of thrombocytes in carps aged 3 months to 5 years was increasing in parallel to their ontogenetic development.

Age and diameter classes or growth stages as criteria for the implementation of thinning

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.

Verticillium wilt causes serious losses in the cultivation of shade trees, especially Norway maple (Acer platanoides L.).In 1993 research was started aiming at the development of Verticillium resistant rootstocks for Norway maple. Efficientmethods to select and screen for resistance in maple were developed, leading to several large-scale selection experimentscarried out in the period 1994-1996. This resulted in a first selection of about 300 plants out of a total of nearly 20 000 seedlingplants. An attempt was made to propagate these plants vegetatively in order to develop small clones for resistancetesting. During this stage of the research many plants were lost because of failure to propagate. After a second screeningfor resistance 35 plants were selected for further examination. Vegetative propagation was continued and from 2000 onthe performance of about 15 clones could be tested on naturally infested fields as well as after inoculation. The resultsof the field test show a clear selection response with disease incidence in plants of the selected clones being 50% lessthan in the seedlings and the randomly chosen clones. Within the group of selected clones there was a substantial variationbetween the clones with some clones having no disease at all whereas in other clones some plants showed serioussymptoms. Results of the field tests will be presented and the possibilities for solving the Verticillium wilt problem inmaple by means of using clonal root-stocks that are resistant to Verticillium wilt will be discussed.

Viruses as phytopathogenes have been discovered at 1892, and 638 plant's viruses have been identified at 1989. Some of its may be epidemic and to cause significant yield losses of cultivated crops. Increasing resistance of the single plant and populations is the necessary condition for the control of viruses spread and damage. Our proposals for the increasing resistance to viruses: For the single plant the soft correction of plant's metabolism with pretreatment of the natural bioantioxidants and immunizators - steroid glycosides. It results in lowering of virus infectivity, degree of plant's affection and increasing of the yield on 11-41% in fact (in ToMV-tomato pathosystem). For the plant's population- increasing to the necessary proportion the lot of tolerant and resistant forms into the plant's assortment; - selection of resistant and tolerant forms from populations have been selected earlier as resistant to other pathogens and obtaining of the basic material collection with complex resistance; - hybridization programs and developing of tolerant and resistant hybrids; - use molecular markers of resistance for the limitation of virus infection backgrounds in the breeding programs.

Overproduction of sugar causes a reduction in the acreage under sugar beet. That is why new non-food technologies for exploitation of agricultural products are sought. Utilization of beet for liquid fuel production could be one of them. The aim of experiments with sugar beet raw juice fermentation was to verify the possibility to return a part of distiller's slops back to the fermentation process and thereby to obtain stillage with higher content of dry solids. This would bring about energy savings during slops thickening and drying. Tests with recycling of different portions of stillage (20, 25 and 30%) back to the fermentation stage were carried out. No significant increase in dry solids content in mash was found and therefore no energy savings during thickening can be expected. The only savings can be made in water consumption that is replaced by slops.

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⁺.

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.

Endogenous content of abscisic acid was studied in a set of two winter cultivars of barleys (Lunet, Cenader), one spring cultivar (Akcent) and five winter cultivars of wheat (Mironovská, Samanta, Šárka, Zdar, Apache) and one spring cultivar (Leguan) in the course of cold hardening of hydroponically grown plants. Freezing tolerance was also determined in all barley and wheat cultivars under study. In none of the barley varieties did cold hardening of plants induce any significant change in abscisic acid content. In wheat plants exposed to cold hardening, the cultivars Apache and Leguan showed a slight transitory increase in abscisic acid content. Abscisic acid content in leaves was very similar in the other wheat cultivars. Neither in barley nor in wheat was the level of freezing tolerance associated with endogenous abscisic acid content or with its transitory changes during cold hardening.

In our previous study of Claviceps purpurea three populations were found: G1 on open localities, G2 from shady or wet habitats and G3 on Spartina stands of coastal salt marshes. The latter two are also chemoraces. In the Czech Republic, isolates of G1 and G2 were found. The ability of four isolates representing these populations to infect and develop sclerotia on different host species (Holcus lanatus, Helictotrichon pubescens, Phalaris arundinacea, Dactylis glomerata, Arrhenatherum elatius, Bromus inermis, Bromus erectus, Elytrigia repens, Avenella flexuosa, Lolium perenne, Poa nemoralis, Poa annua, and different cultivars of Poa pratensis) was studied along with their alkaloid production. P. pratensis and D. glomerata were infected by all the isolates and sclerotia were formed by isolates 207 (G1) and 434 (G2), and on two P. pratensis cultivars even by 481 (G3). Infection ability (formation of sphacelial stage and honeydew) was less host-restricted than formation of mature sclerotia. G2 and G3 strains infected A. flexuosa without sclerotia formation. L. perenne was infected only once by strain 207 (G1) without sclerotia formation. P. annua (natural host of G2), was infected by all isolates, but no sclerotia were formed even with G2 strains. From the two G2 isolates, strain 434 from Dactylis formed sclerotia on five host species, whereas isolate 475 originating from Phragmites stand formed only sphacelia. Composition of alkaloid mixture produced in sclerotia of the same strain from various hosts confirmed that host plant does not influence the type of alkaloids produced, only their ratio.

Leaf samples from 12 peach cultivars (Prunus persica [L.] Batsch.) (Early Crest, May Crest, Flavor Crest,Sun Crest, Fayette, Katherina, Loadel, Andross, Everts, May Grand, Firebrite and Fairlane) grafted on four peach root-stocks were analyzed for their nutrient content. The analysis of variance for leaf nutrient concentrations indicated very significant effects and interactions among cultivars and rootstocks. The rootstock effect on the absorption of nutrient elements was higher for Ca, K, P, Mg, N, and lower for Cu, Zn, Fe, Mn, and B. Generally cultivars grafted on GF 677 had higher N, K, Fe, Cu and lower Zn, Mn, and B, while leaves from cultivars grafted on wild seedlings were found to contain higher Mg and lower P, K, Fe concentrations. Leaf B and Ca were higher for cultivars grafted on Sant Julien GF 655/2, while cultivars on Damas GF 1869 had higher P, Zn, Mn and lower N, B, Ca, Cu concentrations. Leaf N was lower for Fayette on all four rootstocks and significantly different from all other cultivars. Leaf P was lower for Everts and higher for Katherina. Lower concentrations were observed in Early Crest for Fe and Zn, in Andross for Mn, and in Loadel for B, while Flavor Crest had higher concentrations of all these elements. Leaf Zn was the highest for Sun Crest on wild seedling and the lowest for Early Crest on the same rootstock. Similarly leaf N was the highest for Katherina on Damas and the lowest for Fayetteon the same rootstock. Also leaf Mg was the highest for Fayette on Damas and the lowest for Fairlane on Damas. Peach tree mortality was the highest for Damas 1869 and lowest for Sant Julien. Also tree mortality was highest for Early Crest and Sun Crest and lowest for May Grand, Firebrite, and Katherina. The observed trends in the leaf nutrient composition, as regards the cultivars, rootstocks and their interactions, emphasize the importance of these factors on a new peach orchard establishment and macro-microelement fertilization.

The focus of this article is on the emerging private farming in Slovakia, mainly on newly re-established class of private farms. The aim is to analyse the wants and the needs and the current situation of farming entities represented through the sample of 412 farmers spread in two production areas in South and Northwest Slovakia. In the questionnaires, farmers were asked not only about the objectives but as well about their subjective feelings of their current situation in terms of economy, their life standard and their planes to the future.

The market extension generally affects growth performance positively by allowing an expansion of markets, by increasing outside competition as well as by more rapid diffusion of new products, processes and research output between national economies. The positive effects of considerable market on productivity are indubitable. However, two other weighty phenomena of the process are necessary to investigate, effects of regulatory policy and market power exhibits. Agriculture as a sector belongs to those, where the support policies exist for a long time. Nevertheless, the last decades have witnessed considerable changes in this sector among most of developed countries and their agricultural/regulatory policies. It has been perceived, that the agriculture for 21st century cannot be separated from the other components of agri-food sector. The economic importance of the processing and finalization stages (i.e. food industry and food distribution) has increased over time. There are concerned inter-relationships between the market structures development and the crucial factors of the interconnected markets developments in the framework of production verticals of agricultural commodities. Reflecting the steadily more sophisticated supply side behaviour, solution is based upon the demand oriented approach explaining changes of the position of agriculture within the agri-food chain. Conflict of interest between the regulatory/agricultural policy and the market power of input supply and output processing firms and retail notably has increased dramatically. Economic manifestation of the increasing market power on the demand side as well as the impact of market interrelationships and change of policy regulation efficiency within commodity chains are characterised there. The position of agriculture within the agri-food chain has changed and the influence of farmers has decreased. Success of agricultural enterprises in achieving their operational goals is still more influenced by improvements in productivity and by competitiveness of other "links" of the agri-food chain.