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Yellowing of Norway spruce is a relatively common problem in many regions of the Czech Republic. At some places, it is also connected with forest decline. This unfavourable phenomenon is initiated by several ecological as well as anthropogenic processes. One of the most important is the imbalance of forest stand nutrition. Particular reasons lead to nutrient deficiency, especially deficiency of magnesium. Solution to this undesirable trend is a profound ecological analysis and cause-oriented treatments. Besides decreasing air pollution impacts, fertilisation with deficient nutrients represents a successful treatment in the forest stand management in affected areas. In the area of interest, application of relatively small amounts of appropriate fertiliser (SILVAMIX Mg) led to considerable improvement in the defoliation dynamics and yellowing progress since the first year after application.

Molecular sampling of HSVd in grapevines in the environs of hop gardens was performed. Specific RT PCR primers were designed to unambiguously distinguish between HLVd and HSVd infections. These primers were used for detection and analysis of HSVd cDNAs from individual samples by thermodynamic methods, TGGE and cDNA heteroduplex analysis. We found that at least 70% of grapevine samples from locations close to hop gardens inNorthern Bohemia(Žatec and Úštěk hop production areas) were infected with HSVd forming populations containing quasispecies. Particular sequence variants, dominant in grapevines from wine-growing areas like Znojmo, were also found in minor private vineyards. HSVd was experimentally transmissible (80% success) from these samples to Osvald's clone 72 of Czech hop, where according to the cDNA library screening, one of the dominant HSVdg variants corresponding to AC E01844 was detected in early populations three weeks p.i. HSVd was detected neither in reproduction materials nor in examined hop gardens. However a potential danger for hop cultivation, consisting in the high biological potential of HSVd spread is discussed.

Four kinds of cereal crops were grown without farmyard manure application. The effect of farmyard manure was supposed to be replaced by post-harvest residues (PH treatment) or by ploughing the total by-product, i.e. straw (PZ treatment) into soil. After seven years of application, this soil farming system did not influence the contents of Cox and Nt in soil. The amount of organic carbon had declined after the first year, but in the following years it remained at the same level (1.2%). The total nitrogen content increased from 0.143 to 0.166% without any considerable difference between the treatments. The amount of microbial biomass (C_mic) in PH treatment had been varying and in 2000 it decreased approximately by a half (from 215.96 to 132.00 mg C/kg of soil dry matter). The input of organic matter due to ploughing the whole by-product (PZ treatment) into soil acted favourably and the value of C_mic in 2000 was quite comparable with the average values of the individual years of 1994-1997. This land management and cereal growing caused a reduction of the ratio of microbial biomass carbon to soil organic carbon (C_mic/C_org). In the year 2000, the values decreased from 2.59 to 1.09% and from 2.88 to 1.82% in PH and PZ treatments, respectively. The amount of the biologically releasable nitrogen (Nbiol) and the intensity of nitrification were the highest in the year 2000. There was a moderate negative correlation (r = -0.474) between the N_biol values and biomass amount values in PZ treatment, and a very close negative one (r = -0.972) in PH treatment. This relation became strong in both treatments when the values Cmic/Corg and Nbiol were compared, i.e. r_PH = -0.863 and r_PZ = -0.921. The results confirmed that the amount and the quality of organic matter influence microbial biomass and its activity which is responsible for the nutrient release.

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.

The structure of crop production (areas under crops, crop yields, fertilization) in 15 agricultural farms in potato-production and mountain regions of the Czech Republic was analyzed to evaluate the relations between NPK fertilization level, percentage of perennial forage crops on arable land and grain yields as the basic indicator of crop production output. A multifactor analysis based on simple regression equations indicated direct relations between the two above-mentioned factors and yield. Correlation and regression analyses demonstrated a close correlation between grain yields and percentage of perennial forage crops on arable land especially when lower nutrient rates in fertilizers were used (below 100 kg NPK.ha arable land). This relation was expressed for the whole set of initial data by the equation: Grain yield t.ha^-1 = log² (NPK rate in kg.ha^-1 arable land + X% of perennial forage crops). The coefficient of perennial forage crop effect (X) in the range of 0-1.47 can be explained by soil enrichment with nitrogen, mobilization of other nutrients, improvement of soil structure and reduction in the weed infestation of soil. The effect of perennial forage crops on grain yield increase was quantified (estimated) from the whole set of data using the above equation at X = 0 by the value +0.42 t.ha^-1. The yield increase per 1 kg NPK.ha^-1 of arable land amounts to 0.0501 t.ha^-1, i.e. every 1% of forage crops on arable land increases the grain yield by 0.023 t.ha^-1 within the set. The relation between actual and theoretical yield of the whole set is demonstrated by correlation coefficient (r = 0.9332) if the effect of perennial forage crops is estimated by coefficient X = 0.95, if the effect is estimated by coefficient X = 1.47, the correlation coefficient is even higher (r = 0.9977).

The paper analyses the economic and policy gap between the agriculture in Slovakia and the EU member states from the perspective of the future accession of this country to the Union. As it concludes, the deterioration of terms of trade during the transition period creates also problems for the accession negotiations, because this fact seems to legitimate the equitable implementation of the CAP in all member countries after the East-enlargement of the Union. The paper is arguing, on the basis of income simulation, that that the Commission proposal on reduced direct payments for the newly admitted countries would, in case of Slovakia, generate an improvement of the sectoral income only if they are topped by rural development measures.

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.

This paper introduces partial results of the research project QC 1140 aimed at the efficiency of enterprises operating in the system of organic farming, especially considering the use of grassland linked with cattle management. Economic evaluation of cattle management in the system of organic farming is compared with conventional enterprises. Economic evaluation applies to dairy cattle and beef cattle. Proposals of the measures will be formed with respect to the results of analysys, which should contribute to the support of organic enterprises and to better satisfaction of the increasing demand for organic food.

The subject of this paper was to assess the effects of pulverised dolomitic limestone applications on prosperity of Norway spruce (Picea abies L.) plantation and on the soil in extreme ecological conditions of the Jizerské hory Mts. The characteristics such as plant mortality, annual height increment, diameter of root collar (stem base diameter), crown diameter, nutrient analyses and some data from soil analyses are evaluated in this paper. An eleven-year period of observations is summarised. According to the observations and measurements carried out until now, the effect of limestone applications (1 kg per tree) on the spruce plantation prosperity seems to be positive without any serious negative impacts on the soil.

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.

Soil map at the scale 1:250 000 was set up by means of transformation of the published and later digitised soil map of theCzechRepublic. The legend to this map reflects a new classification system of Czech soils that can easily be correlated with the reference international classification system FAO-WRB. In the next step this map was converted into the SOTER system, which links the soil cover to the geomorphology. The modification of the original SOTER procedure consisted in the abandoning of the consequent hierarchy geomorphology - lithology - soil associations. Only in territories characterised by rather shallow transported slope deposits over compact or consolidated rocks was this principle observed in the SOTER unit delimitation. In flat landscapes covered with deep sediment deposits the prevailing soil cover (mosaics of taxonomic units and their parent materials) determines the borders of SOTER units. Ten major landscape units were delineated. They are based on relief intensity and hypsometry. The slope gradient map enables a detailed insight into the landscape geomorphology. 158 SOTER units are defined by the combination of 10 major landscape units, 21 grouped soil parent materials and 19 grouped soil units. The single factors and their combinations are reflected in GIS layers that can be matched with the map of soil associations. The major soil regions, which are conceptually close to the SOTER units, will be delimited as homogeneous mosaics of the individual SOTER units with respect to regionally integrating factors (climate, vegetation). The interconnection of the geometric and attribute data generates the soil information system. This system is anticipated to be used for the soil policy regulation both in the Czech Republic (PUGIS) and within the EU (EUSIS).

In small-plot field trials conducted in 2000-2002 we studied the effect of fungicides on the yield and selected technological parameters of grain of malt barley and on malt. For the treatment we used Cerelux (active ingredients: fenpropimorph, flusilazole), Amistar (azoxystrobin) and Caramba (metconazole) applied in two stages of stand development (DC 47 and 55). Compared to the untreated control plants the yield grains ranged between 6.9 and 16.5% after the application of fungicides. The application of fungicides increased the proportion of full grains and had a favourable effect on the chemical composition of grain. After the treatment with azoxystrobin the content of N-substances decreased from 11.43 to 11.07% as compared to the controls. The highest starch content of grain was observed after the application of the active ingredient metconazole; the average content ranged between 64.44 and 64.62%. Compared to the controls the highest relative yield of malt starch (124.2-125.2%) was achieved after the application of azoxystrobin or a combination of azoxystrobin and metconazole in the DC 47 stage. The highest average attainable degree of fermentation was 78.57% and was discovered in the untreated control.

Automatic steering devices for farm machinery and tractors have the task to relieve the driver from the physical and mental stress of monotonous steering work. Simultaneously, they are intended to help exploit machines and tractors closer to their full performance and improve the quality of work. However, it is not possible to rule out malfunctions or breakdowns of sensors, gaps in guidance lines, obstacles in the field such as ditches or pylons, temporary hazards like the sudden appearance of animals in front of a moving machine or a temporary lack of concentration of the operator. Most of these problems may be prevented by a safety system for automatically steered agricultural machinery developed at the Department of Agricultural Engineering of the Martin-Luther-University in Halle. The function of the components of the safety system and preliminary results obtained in field experiments are introduced and discussed.

Inclusion of the countries in Central Europe (CECs) in the Common Agricultural Policy (CAP) of the European Union raises a large number of issues, not the least in the context of the accession negotiations among the current EU member states and the newcomers. However, in the process of enlargement, negotiations will also be necessary with other countries. This is because both the EU and the accession candidates have commitments in the WTO and inclusion of the CECs in the CAP may affect the nature of these commitments, as well as the ability of the enlarged Union to honour them. The paper deals with the fundamental problems in connection with presented themes.

The aim of this presentation is to introduce partial results of this research project aimed to the efficiency of businesses working with the organic systems. The proposal of mesures will be formed with the respect of results of analysis to support organic businesses, to increase organic land area corresponding with the progress in the EU and therefore to help to satisfy increasing demand for organic food, last but not least also to prove, that organic agriculture is truly functioning part of multifunctional agriculture.

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).

An assortment of 15 cultivars of root parsley was studied in field experiments to evaluate morphological characteristics, market yield, content of selected minerals and nitrate content. Storage ability of roots was also assessed. Mean root weight ranged from 87 g (cv. Bartowich Long) to 129 g (cv. Atika). Root head diameter was from 39 mm (cv. Lange) to 49 mm (cv. Halflange Omega and Hamburg). Mean root yield amounted to 1.35 kg/m² and the highest value was found in cv. Atika. Nitrate content did not exceed the tolerance limit ranging from 113 to 617 mg/kg of f.m. Mean content of K was 4,690 mg, Ca 124 mg, Mg 509 mg, and Na 425 mg/kg of f.m. Weight losses ranged from 10 to 32%; cv. Jadran showed the lowest value. Newer Czech cultivars (Atika, Jadran, Orbis) had a good commercial and growth potential.

Muscle fibre formation takes place during embryonic development and is regulated by the MyoD gene family, which consists of four genes, MYOD1, myogenin, MYF5 and MRF4. A relationship was studied between MYOD1, myogenin and MYF5 genotypes and microstructural characteristics of the m. longissimus lumborum in pigs - crosses: Pietrain × (Polish Large White × Polish Landrace). The data included 115 unrelated animals slaughtered at about 105 kg live body weight. Within 45 min after exsanguination, samples were taken from the m. longissimus lumborum, frozen in liquid nitrogen and later analysed for the diameter of slow-twitch oxidative, fast-twitch oxidative and fast-twitch low-oxidative fibres, their proportion in a bundle, the proportion of pathological changes and number of fibres per unit area. The RYR1 and MyoD genotypes were determined using the PCR-RFLP technique. A significant or highly significant relation was observed between the diameter of all types of muscle fibres and genotype RYR1 - the highest values were recorded for homozygotes TT (genetically stress-sensitive). A relation between MyoD genotypes and microstructural characteristics of the m. longissimus lumborum was analysed on a group of 93 animals of the genotype CC or CT at locus RYR1. Sex appeared to have no significant effect on the muscle microstructural traits in this group of animals. The content of fast-twitch oxidative fibres (FTO) was significantly related to the MYF5 genotype, whereas that of fast-twitch low-oxidative fibres (FT) was affected by the MYOD1 and MYF5/DdeI genotypes. The proportion of angular fibres in a bundle was related to MYF5/HinfI genotype. The results showed that MyoD genes could be considered as candidate genes for some microstructural characteristics of m. longissimus lumborum in pigs.

The differentiation between anthropogenic and geogenic loads of the soils by potentially risky elements was observed. The collection of soil horizon samples from 21 localities with different anthropogenic loads (imission fall-outs, floods, historical mining) and geogenic loads (lithogenic, chalcogenic) was composed. The soil characteristics (pH, C_ox), total content of 13 potentially risky elements, content of potentially risky elements in the extract of 2M HNO₃, 1M NH₄NO₃ (mobile forms) and 0.025M EDTA (potentially mobilizable forms) were detected. The solubility as the ratio of total content and the content of risky elements in the other extracts was calculated. The differences between the solubility for each risky element and for each type of the load were determined. It was concluded that the highest solubility was determined in the fluvisols contaminated by the floods and in the soils contaminated by imission fall-outs. Significantly lower solubility of potentially risky elements was determined in the soils with geogenic loads. The efficiency of the used extracts for the differentiation of the soil load was assessed (2M HNO₃, 0.025M EDTA). The types of geogenic loads were characterised in the extent of used soil collection. Geochemically anomalous parent materials and soil types developed on these parent materials were described.

The fungus Gymnosporangium sabinae (Dicks.) Winter was found only at three locations during the years 1965 to 1990 in Slovakia, they were the Arboretum at Mlyňany, Topoľčianky and Gbely (JUHÁSOVÁ 1973, 1975, 1998). We noticed a more frequent occurrence of this fungus during recent years. The life cycle, range of woody host plants and degree of damage on pear leaves at selected locations inSlovakia are described.

The objective of this study was to establish the genetic relationship among cultivars commonly used as donors for resistance to Plum pox virus (PPV) in order to identify the putative sources of resistance to PPV. The plant material tested represented the European, Central Asian and Chinese ecogeographical groups of cultivated apricots as well as the wild Dzhungar-Zailij population of Prunus armeniaca L. Forty-eight native accessions as well as the resistant (or tolerant) cultivars Harlayne, Stark Early Orange (SEO), Goldrich, Vestar and two hybrid forms Vestar × SEO (LE 3276) and Velkopavlovická × SEO (LE 2904) were screened by means of SSR analysis. To elucidate genetic relationships among apricot germplasm, a dendrogram was produced using neighbor joining (NJ) analysis of Nei's pair-wise genetic distances over 14 polymorphic SSR markers. On the dendrogram, resistant cultivars were separated into two different clusters suggesting two different sources of resistance to PPV. As was expected from pedigrees, SEO, Vestar, LE 2904 and LE 3276 were grouped together in a cluster adjacent to the European cultivars. Resistant cultivars Harlayne and Goldrich were within another group containing Central Asian apricots and Dzhungar-Zailij form.

Viroids as the smallest pathogenic circular single-stranded pathogenic RNAs form populations of quasi-species, whichhas been recently identified by thermodynamic methods like TGGE pre-selection and heteroduplex analysis. It was foundthat replication under thermal stress led to enormously high level of viroid mutagenesis. Mostly multiple mutants havingnon-random distribution of base changes were found. A specific "hot spots" were identified in the regions, wherea characteristic "pathogenicity domains" are localised in different viroids of the pospiviroidae family. Specific viroidmicroevolution was observed upon artificial inoculation of non-host plant species. Our results suggest that viroid propagationunder physiological stress can be assumed as important factor, which is among others, responsible for an appearanceof viroid quasi-species in the nature. Evolution and new viroid patotypes could accumulate due to environmental stressincluding various pollutants may be a potential danger for cultured plants.

The random amplified polymorphic DNA (RAPD) technique was used to evaluate both genetic diversity among 19 soybean accessions included in the Czech National Collection of Soybean Genotypes and their potential as a new source of genetic variations for soybean breeding programs. Only 22 of all the 40 random primers used in RAPD reactions showed polymorphism acceptable for an effective characterisation of these accessions. Altogether 122 highly reproducible RAPD fragments were generated, 55 of them were polymorphic (46%). However, because of the previously observed low degree of RAPD polymorphism in the case of Glycine max, fragments with low level of informativeness were evaluated, too. Presented results enable the selection of genetically distinct individuals. Such information may be useful to breeders willing to use genetically diverse introductions in soybean improvement process.

On one-year-old and two-year-old plantations of lemon balm observations on the occurrence of plants showing symptoms of fungal diseases were made in 1998-2001. Many fungi were isolated from roots, stem bases and leaves separately on mineral medium. Species of Fusarium, Phoma and Rhizoctonia solani were obtained from the roots and stem bases whereas Alternaria alternata, Phoma spp., Septoria melissae and Botrytis cinerea were most often isolated from the leaves showing symptoms of necrosis.

The fungal population colonizing the seeds of fodder galega cultivated in pure stand was greater than that cultivated in mixed stand. No significant differences were observed in the species composition of the obtained fungal colonies. In all analyzed combinations, Alternaria alternata was predominantly isolated from the seeds. Other saprophytic fungi were represented by the following species: Epicoccum purpurascens, Cladosporium cladosporioides as well as fungi representing genera Mucorales: Mucor hiemalis and Rhizopus nigricans. Among the pathogens, Botrytis cinerea was most often isolated. The mineral and SNA medium as well as the process of superficial disinfecting of seeds reduced the number of isolated fungi.

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

Within the EU project DREAM there is a programme of work investigating the molecular basis of virulence and avirulence in Meloidogyne chitwoodi and which involves partners from the Netherlands, France and Scotland. In Wageningen AFLPs are being used to examine genetic diversity between populations of M. chitwoodi. Partners in Wageningen and INRA are using M. javanica and M. incognita as model systems to isolate genes producing secreted proteins that could be implicated in the host pathogen interaction. They will search for homologous sequences in M. chitwoodi. At Rennes two-dimensional electrophoresis (2DE) studies are being conducted. The PCR based suppressive subtractive hybridisation (SSH), has been used at PRI and SCRI to compare avirulent and virulent nematodes and infected plant material (resistant and susceptible) at different times after infection.

The monitoring was carried on in the years 1996-2000 in the polyfactorial P-A field trial in Lukavec, Pelhřimov district. The given locality is characterized by low fertility sandy-loamy cambisoils, by long-term average annual rainfall of 653 mm, by average annual temperature of 7°C and its altitude is 620 m. The field trial included different organic fertilizations; graduate N-doses, different soil tillage as well as different forecrops. It manifested in this group of field trials that the forecrop value of red clover and dung manured potatoes before winter wheat was practically the same in the given locality. The optimal N dose for potato yields was about 80 kg N.ha^-1. In oats the yields after red clover with using the Horsch system in spring were significantly lower than after embedding of red clover in autumn. In cereals, graduated N doses increased the numbers of ears (panicles) per m2, but the mass of 1000 grains often decreased. In addition, N content in grain and straw increased with N doses, while pH annually decreased by 0.1 to 0.4.

Present study focuses on making best possible use of male gametophytic generation in carnation breeding program. Exploration of pollen population revealed the existence of variability in terms of pollen morphology and histochemical content among as well as within varieties and species of Dianthus caryophyllus and D. chinensis sufficient to make selection. Pollen grain size and histochemical content were found to be associated with germination capacity and pollen tube growth rate. In addition, pollen germination capacity and elongation of pollen tube in response to presence of culture filtrate from F. oxysporum. f.sp. dianthi causal organism of fusarium wilt in carnation was found to be governed by pollen grain size and histochemical content of pollen grains. Entire result suggests the possibility of selecting the desired pollen grains from a pollen population and possibility of attempting selective pollination in carnation breeding program.