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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.

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.

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.

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.

Decreasing numbers of tourists to the Czech Republic point at a weakening competitive position of Czech destinations during the most recent years. For many communities, tourism may be a short-lived economic dream when understanding of tourists´ perceptions and travel motives is lacking. The two objectives pursued in this study are 1) an identification of the positions of competing destinations and 2) an a-posteriori segmentation with psychographic variables. Market segmentation becomes the crucial factor in the strategic design process of target marketing. Like many other markets, tourism markets do not respond homogeneously to marketing activities. Subdividing visitors into useful groups may provide a basis for competitive advantage. Our study establishes taxonomy of visitors to Southern Moravia. The study tries to overcome well-known insufficiencies of single segmentation approaches by exploiting the advantage of the multivariate nature of combined push factors, pull factors, and other factors of more restrictive nature (i.e. time and money). The segmentation task employs multivariate data analysis techniques such as factor analysis, cluster analysis and multi-dimensional scaling. Recent research on the European Vacation Style Typology is incorporated.

One of the conditions of accession of Slovakia into the European Union is the existence of a developed land market. At present, the official land price is mostly used in the evaluation of agricultural land. The price was calculated on the basis of normative production and normative costs required to achieve such production. As the land market gradually develops, market prices come into being; reflecting the effect of real market forces. With the full-fledged market prices, the task of official prices will be just an informative one. The land market prices will gradually assume all the tasks of the current official prices of the agricultural land.

The economic importance of agricultural sector in Slovakia declined during transition period. There are several reasons for this: declining terms of agricultural trade, extreme weather, transformation of agricultural sector, unclear property rights in transition period, short-run privatization distortions, transformation of up and downstream sectors, world market fluctuation, decline of real wages, low stability of agricultural policy and other. The development in economic market was paralleled by activity in political market. After initial liberalization, agricultural protection subsequently increased. The EU accession influences both levels of protection as well as instruments of agricultural policy.

The effect of phenylurea with reported cytokinin-like activities on seed germination, seedling growth, activities of antioxidant enzymes, polyphenol, peroxidase, indoleacetic acid oxidase, and total phenolic compounds, flavonoids was investigated in stressed barley seedlings. The application of phenylurea decreases the activity of peroxidase, indoleacetic acid oxidase and increases the activity of polyphenol oxidase with decrease in total phenolic compounds and flavonoids and consequent increase in growth rate. Saline (NaCl) stress in barley seedlings causes an increase in total phenolic compounds, flavonoids and enhancement of peroxidase and indoleacetic acid oxidase activities and consequent decrease in growth rate. The adverse effect of salt stress on germination, antioxidant enzymes, phenolic compounds, flavonoids can partially be rectified by phenylurea.

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.

The redox potential of flowers of Achillea plants was measured by means of a puncture method. Measurements were performed in 6 taxa (species and hybrids) in the stage of bud formation, full flower and flower shedding in 2000 and 2001. The content of essential oil was estimated in the period of full flower. Differences in the values of redox potential (177-213 mV) and contents of essential oil (1.5-6.1 ml/kg) measured in individual Achillea species and their hybrids were significant. The correlation between the content of essential oil and values of redox potential was closely below 95% of significance.

Using the Ames bacterial mutagenicity test and an in vivo micronucleus test, we investigated the antigenotoxic effect of ellagic acid on the genotoxicity of three mutagens: amino-methylimidazo-quinoline (IQ), aflatoxin B1 (AFB1), and N-nitroso-N-methylurea (MNU). Ellagic acid is a naturally occurring phenolic compound which is found in a variety of soft fruits and vegetables. The effect of this compound on the immunosuppressive activity of mutagens was followed in vivo by the chemiluminescence test. In the Ames assay, ellagic acid at concentrations of 300 and 30 μg/plate demonstrably inhibits the mutagenic activity of two indirect mutagens: IQ and AFB1. The concentration of 300 μg/plate had the strongest effect on mutagenicity of all concentrations of IQ in strain TA98 of Salmonella typhimurium, whereas in strain TA100 concentration of 30 μg per dish of ellagic acid was more effective than 300 μg per plate. Also in combination with different concentrations of AFB1, ellagic acid proved to be a strong antimutagen. In this case the lower of the two effective concentrations - 30 μg/plate - had a much greater antimutagenic effect on both strains tested than 300 μg/plate. In combination with the direct mutagen MNU, ellagic acid did not show any marked antimutagenic effect at most of the concentrations tested in strain TA100. Only the highest concentrations of ellagic acid reduced the mutagenic effect of MNU weakly and only in combination with two lower concentrations of MNU. In the micronucleus test, three-day oral application of ellagic acid prior to the applicaton of AFB1, IQ, or MNU, respectively, markedly reduced the numbers of micronuclei induced by these three mutagens in polychromatophilic erythrocytes of mice. Chemiluminescence test with mouse granulocytes proved that ellagic acid not only prevents the inhibitory effects of mutagens on free oxygen radicals and hydrogen peroxide production, but that this production is stimulated by ellagic acid in combination with mutagens even to a greater extent than by ellagic acid alone. From these results we can deduce that ellagic acid repairs strong immunosuppressive effects of all mutagens applied.

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.

This paper presents the results of the distribution of salinity characteristics (electrical conductivity and sodium adsorption ratio) of groundwater, and based on the results, it reports the evaluation of the salinity and sodicity hazards in the fluctuation processes of shallow mineralised groundwater, or in the processes if such groundwater is used for irrigation. The issue was studied for the soil-water environment in the south-east of the Danube Lowlands for the period 1991 to 1994. The measured data and data taken from archives were processed in the form of graphical attachments (appendixes, supplements, graphical documentation) - maps, by means of the kriging interpolation method. Groundwater in the area in question is classified as highly mineralised with a high hazard of salinisation of the subsurface soil environment. The average annual values of the electrical conductivity of groundwater ranged from 600 to 2100 µS/cm in the examined period. The sodium adsorption ratio values ranged from 1.7 to 22.0 and indicate low, medium to high sodium salinisation of the environment due to groundwater. The distribution of electrical conductivity and sodium adsorption ratio on the regional scale can serve as a reference basis for the evaluation of changes in the groundwater salinity after 1994.

Three maize inbred lines (Os86-39, Os89-35 and Os87-24) were grown in pots with Eutric Cambisol using 9 fertilisation variants (control 10 kg/ha Zn - on soil surface; 5 kg/ha - foliar application; 61 kg/ha P; 61 kg/ha P and 10 kg/ha Zn - on soil surface; 61 kg/ha P and 5 kg/ha Zn - foliar application; 183 kg/ha P; 183 kg/ha P and 10 kg/ha Zn - on soil surface; 183 kg/ha P and 5 kg/ha Zn - foliar application). The effects of phosphorus and zinc fertilisation on the dry matter yield, plant height, stalk diameter as well as phosphorus and zinc concentrations in ear-leaves were investigated. Significant differences were found between the lines in all parameters investigated except for phosphorus concentration. Line Os87-24 was characterised by the best results in the total biomass production. Zinc fertilisation decreased while phosphorus fertilisation increased total plant dry matter mass. Phosphorus fertilisation increased its concentration in the ear-leaves. Zinc fertilisation, especially foliar, resulted in Zn concentration increase in the ear-leaf of the lines investigated.

In this four-year study, fruits of Golden Delicious cv. randomly sampled from four different orchards on M 9 were kept at 1 or 2^oC in air storage, and in the course of storing individually assessed for weight, skin colour, skin blush, skin waxiness, flesh firmness, vitamin C content, total acid content, pH value, total sugars, dry matter and calcium content. Changes in some of these fruit quality characteristics during storage are presented and compared with their course during storage both in the cellar and ULO. The maximum storage life of the fruits in the air storage was estimated at 150 days on average. From individual fruit data, correlations between all the observed characteristics at different stages of the storage period were calculated. Fruit weight was positively correlated with dry matter, vitamin C, sugar and acid content, but negatively correlated with flesh firmness and calcium content. Fruits with more skin blush were correlated with higher vitamin C. Flesh firmness was mostly correlated with dry matter content, but negatively correlated with calcium content and pH values. Vitamin C content was positively correlated with total acids, but negatively correlated with pH values, sugar:acid ratio and calcium content. Total acids were negatively correlated with pH values and sugar:acid ratio. At the end of the storage period, the total acid content was also correlated with dry matter content. Total sugars were closely correlated with dry matter content and negatively correlated with calcium content. Calcium content was very closely negatively correlated with dry matter content, and also negatively correlated with the sugar:acid ratio.

Inoculation experiments were carried out on a set of trees with imagoes of Ips typographus L. which origin from the Šumava Mts. and the Křtiny Training Enterprise. The objective of back inoculations was to determine whether species found on the surface of Ips typographus imagoes spread after the inoculation also through host tissues. It the vicinity of inoculation by Ips typographus imagoes, marked necrotic zones are evident including symptoms of the penetration of vascular pathogens through phloem and sapwood. The most marked reactions were observed in case of inoculation by an untreated Ips typographus imago. Treatment of Ips typographus imagoes by Ibefungin and Fundazol preparations did not demonstrate expected effects in full scale. The spores of several ophiostomoid fungi like Ceratocystis polonica (Siem.) C. Moreau were observed on the surface of bark beetles and at the same time were re-isolated from wounds inoculated by Ips typographus imagoes. The other fungi like Ophiostoma bicolor Davidson & Wells, Leptographium cf. lundbergii Lagerberg & Melin., Pezicula eucrita Karst., Phomopsis sp. and other were found in wounds with the imagoes artificial infection.

In identifying perceptions and attitudes relevant to consumer acceptance of goods originating in different countries, it would be extremely helpful for marketers to have a meaningful and consistent measure that they could apply. This study examines to what extent consumer ethnocentrism as measured by the CETSCALE singularly, as well as in concert with selected demographic and psycho-graphic variables, can predict consumers' evaluation of domestic versus foreign produce. The findings indicate that consumer ethnocentrism is a strong and significant predictor of consumer product evaluations. Including the ethnocentrism variable in a set of demographic and psycho-graphic variables significantly improves the predictive ability of the set. Potential applications of the concept include identification of market segments that react more favourably to domestic or foreign produce, developing effective marketing communication strategies, and supporting location decisions for retail outlet sites.

The analysis of the development of prices in the foodstuffs vertical, it means the prices of inputs into the agriculture, agricultural products, food products and consumption prices of foodstuffs, on the basis of the price scissors, and with crucial products on the basis of the price shares and differences, has shown that price liberalisation with the applied partial regulation of their development within the market-oriented reform has evoked the greatest raise of prices within 1991-2001 regarding inputs into the agriculture, while prices of agricultural products were growing slower. The parity coefficient (the ratio of price indices) between the development of the prices of inputs and outputs became worse as of 1989 to the detriment of agriculture from 93.9 reached in 1990 to 50.3 in 2001, what means a significant opening of the price scissors to the detriment of agricultural producers. That situation was influenced mostly by the development in the first year of the reform but the trend of opening the price scissors, except for 1994, was persisting, though in the last two years the differences in the trends of the development of prices of inputs and outputs have been moderated. At the beginning of the development, the effect of the low level of the agricultural products prices was not adequately reflected in the prices of food producers and consequently in consumer prices. This was influenced mainly by the pressure of food producers evoked by the need of settlement of additional costs connected with the transformation, in particular to the detriment of the agricultural products prices (opening of the price scissors with the parity coefficient dropping from 90.8 in 1990 to 56.5 in 2001), but this negative trend has been stopped in the last two years. A gradual accommodation of demand and supply and a growing competition environment also through large retails established in our country has been reflected in closing the price scissors between the prices of food producers and consumer prices of foodstuffs (the parity coefficient raised from 76.6 in 1991 to 88.7 in 2001). The development of the shares and differences in prices as of 1994 pointed to a substantial differentiation in the development of prices in the vertical of the production and consumption of individual products what was effected by the applied regulation system as well. With milk and milk products, the majority of the evaluated products was showing a slightly raised share of the raw cow milk price in the final food products prices, and in the last three years, also the processor price share in the consumer price. This narrowed the difference between the producer and dealer prices. With slaughter cattle and the major kinds of beef, a gradual decline of the slaughter cattle price share in the processor price was interrupted in 2001, what, to a certain extent, was also caused by the crisis evoked by the BSE and by the minimum price which prevented transferring of these consequences, to a larger extent, to farmers. Similarly, in 2001, a non-standard situation occurred between the processor and consumer prices of the individual kinds of beef. With slaughter pigs and the evaluated kinds of pork, after the period of dropping slaughter pig prices share in the processor price of the major kinds of pork, its growth was

The aim of the experiment in test station was to evaluate productive performance with respect to feeding-technologies through the test for LWs × (LW×L) genotype in pigs. The productive performance as growth capacity, feeding intake and quantitative traits of slaughter value was examined for 144 hybrid pigs divided in two identical groups, where the 1st group was fed ad-libitum and the 2nd one semi-ad-libitum. On the base of profit formula, the ad-libitum system of feeding in pigs is better in all economic features.

The effect of chemical weed control with reduced herbicide rates (pre-em., pre-em. + post-em., post-em.) on weed population density and maize yield was compared in three tillage systems (mouldboard, chisel, disk harrowing) for lessive pseudogleyic soil in north-eastern Croatia(1997-1999). These main weeds were present in all tillage variants: Echinochloa crus-galli (L.) PB., Chenopodium album L., Ambrosia artemisiifolia L., Polygonum lapathifolium L., Equisetum arvense L. and Calystegia sepium (L.) R.Br. The density of all weeds was significantly affected by tillage and it ranged from 204 plants on untreated plots with mouldboard to 372 and 421 plants per m2 with chisel ploughing and disk harrowing, respectively. In comparison with standard tank-mixture of atrazine herbicide (metolachlor 50% & atrazine 20%) at the recommended rate, atrazine-free herbicide combinations (metolachlor + 50% prosulfuron & 30% primisulfuron-methyl; sulcotrione + bromoxynil; thifensulfuron-methyl + nicosulfuron) showed a similar total efficacy of weed control (95-96%). Band spraying with standard treatment at a half-recommended rate combined with mechanical weed control brought a satisfactory total weed reduction (83-87%). The weed control methods had no effects on maize yields that were significantly affected by year and tillage. Compared to the highest yield with mouldboard ploughing (10.2 t/ha), average percent yield depressions with chisel ploughing and disk harrowing were 10 and 22%, respectively.

Development of powdery mildew and leaf rust epidemics was examined on three winter wheat cultivars with different predispositions to powdery mildew in three-year experiments. The progress of powdery mildew and leaf rust on the same cultivar was conditioned by its dissimilar susceptibility to the respective disease. Fit temperature played an important role at the beginning of the particular disease and during its progress. Significant differences in the disease severity of powdery mildew and leaf rust were recorded on single leaves. Disease severity of leaf rust was higher on upper leaves while disease severity of powdery mildew was higher on lower leaves.

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.