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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.

A laboratory incubation experiment with zeolite and glucose was performed to evaluate the effects of zeolite amendment in heavy metal contaminated soils from two smelter areas on some microbial characteristics [Kremikovtzi (K1, K2) in Bulgariaand Příbram (P1, P2) in the CzechRepublic]. The content of microbial biomass showed a tendency to decrease in Kremikovtzi soils whereas in Příbram soils no significant effects were found after zeolite amendment. Respiratory activity and metabolic quotient (qCO2) decreased on the second and third day in Kremikovtzi soils amended with zeolite, no effects were observed in Příbram soils. Heavy metals decreased the content of microbial biomass in Kremikovtzi soils whereas the contaminated soil from Příbram area had the highest microbial biomass compared to non-contaminated soil during incubation, probably due to lower mineralization of carbon. The respiratory activity did not show any significant effects of zeolites on the evolution of CO2 and qCO2 in heavy metal contaminated Příbram soil. The respiratory activity in non-contaminated Příbram soil remained during the experiment lower in comparison to contaminated one, however the addition of zeolite increased qCO2.

A new method was proposed that complements the value of active carbon in the soil expressed as hot-water soluble carbon Chws. The method is based on vacuum measurements of biochemical oxygen demand (BOD) of soil suspensions using an Oxi Top Control system manufactured by the WTW Merck Company that is destined for hydrochemical analyses of organically contaminated waters. Measurements will provide BOD values for particular days of incubation; total limit BODt can be determined from these values, and it is possible to calculate the rate constant k1 of mineralization of a decomposable part of soil organic matter. It is typical of soil organic matter (SOM) of a given soil sample and comparable with the BOD5:COD (chemical oxygen demand) ratio that is used to evaluate degradability of water organic contamination in hydrochemical analytics.

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.

A polyfactorial field trial with alfalfa (Medicago sativa L.) cv. Palava, Jarka and Vlasta was established in Červený Újezd (altitude405 m a.s.l., average year precipitation493 mm per year, average year temperature 7.6°C, clay loam orthic luvisol) in the spring with a companion crop (spring wheat) in rows of a space of125 mm, sowing rate 16 kg/ha of germinable seeds in the year 1998. The stands were cut 3 times per year, the control variant was left without a treatment, the rest were cultivated with a spike or a vibration harrow before the beginning of the vegetation season and after the first cut. The numbers of plants and stems per m2 and dry mass yields were measured. The results were evaluated by four-factor analysis of variance Anova and by regression analysis. The harrowing of the stands resulted in a significantly lower amount of plants per m2 in the end of the fourth year by 23-29%, on average a lower number of stems per m2 (by 13% using double cultivation per year with the vibration harrow). The dry mass yield was significantly influenced only with cv. Jarka (by 5-11% higher in the cultivated fields). The moderately or relatively strong relationship between the plants amount and the time was exponential.

The development of soil limiting values of the protection of the quantity and mainly quality of the crop production tends from empiric values towards critical values, based on ecotoxicity. We present an attempt to derive transfer functions by the means of multiple regression analysis. The substitution of trace elements contents in crops in the prediction equations for fodder or food standards or phytotoxicity limits satisfies the present ecotoxicological demands. We preferred polyfactor relations to simple ones. The exceeding of reference values must be verified by the determination of the hazardous transfer in the field. Therefore the reference values are called testing values. They were derived especially for Cd, Pb, As, Cu, Zn, Ni and Mn. For some trace elements, only protective values can be set up (especially for Cr, Hg, but also for Tl, Be, V). They reflect minimum values that guarantee growing crops without any risks. Experimental data (pot trials) were compared with results obtained in field investigations. The resulting critical values were also compared with the values proposed in Germany.

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

In 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.

Fusarium head blight (FHB) is a barley disease, which occurs every year in various areas of barley cultivation all over the world and the increasing incidence has been confirmed in the Czech Republic also during the last years. We aimed to emply AFLP (Amplified fragment length polymorphism) and SSR (Single sequence repeats) markers to describe diversity among breeding lines with a sufficient level of resistance towards FHB and to find marker(s) associated with the analysed traits. The number of eight accessions including five expected resistance donors and three sensitive lines were tested in the field and laboratory. The field values and the amount of deoxynivalenol were positively correlated (r = 0.92). The laboratory test and content DON manifested also a high correlation (r = 0.73). Several DH lines developed from androgenetic barley progenies of the F1 hybrids between the susceptible line PI 383933 and resistant line PEC 210 or the susceptible line PI 383933 and resistant cultivar Chevron were found resistant towards Fusarium infection in both the field and laboratory tests. Low infestation was found at line DH 37 from combination Chevron × PI 383933 and lines DH48, DH49, DH50 and DH55 from the combination PEC 210 × PI 383933. Cluster analyses based on 68 AFLP and 18 SSR markers demonstrate a genetic relationship among parental genotypes and DH lines.Some DH lines combined a sufficient degree of resistance against FHB and extract content (basic parameters malting quality). Statistically significant differences in malt-extract values were observed between groups of the DH lines possessing and not possessing the AFLP marker CAA/AGC 341bp. The markers will be further evaluated and optionally used for MAS.

As, Cd, Pb and Zn accumulation in the aboveground biomass of seven clones of Salix spp. and changes in element uptake by plants after element addition to soil were studied in a pot experiment. Unpolluted Chernozem (Suchdol) as a control and soils with addition of As (100 mg/kg), Cd (40 mg/kg) and either Pb (2000 mg/kg) (Suchdol-Pb) or Zn (2000 mg/kg) (Suchdol-Zn) were used for the experiment. Significant differences were found in the accumulation of elements between willow clones and also between different element additions to the soil. Although As and Cd uptake slightly increased in Suchdol-Zn soil compared to Suchdol-Pb soil, the element removal from soil was significantly higher in Suchdol-Pb soil due to a significant reduction of aboveground biomass yield in Suchdol-Zn soil caused by Zn phytotoxicity. The yield reduction decreased the uptake of plant-available elements by biomass, thus higher plant-available portions of As and Cd were found in Suchdol-Zn soil. Element removal from soil was more dependent on element contents in willow tissues in Suchdol-Pb soil than in Suchdol-Zn soil, where willow plants exhibited physiological symptoms of phytotoxicity.

Non-symbiotic nitrogen fixation (potential nitrogenase activity - PNA) of soil samples originating from different plots of long-term field experiments (selected variants: Nil, NPK [mineral fertilisation: 64.6-100 kg N/ha/year], FYM [farmyard manure], and FYM + NPK from three blocks III, IV and B with different crop rotation) was determined in laboratory experiments. The symbiotic nitrogen fixation (total nitrogenase activity - TNA) of the same soil samples was evaluated in hydroponic experiments with pea (2001, 2002) and lucerne (2001) in which the soil samples were used as a natural inoculum. The high values of PNA were found in the variants fertilised with FYM in all three blocks and all experiments. Simultaneously, the variants fertilised with mineral NPK reached low values of PNA. The farmyard manuring enhanced the number of free-living bacteria Azotobacter spp. that were identified in all soil samples. In the hydroponic experiments with pea, the highest nonsignificant values of TNA were found in variants B 284 (FYM + NPK) and III 254 (FYM + NPK) in 2001, and B 214 (FYM) and III 214 (FYM) in 2002. Plants inoculated with soil from these variants formed also high amounts of nodules (significant differences in block IV in 2001) and plant biomass. In the experiments with lucerne, the nonsignificantly highest TNA values were found in variant III 154 (NPK). Variants from block III (214, 254) and IV (114 and 154) showed the nonsignificantly lowest TNA values. The rhizobia that effectuate symbiosis with pea were more active in the soil samples in 2001 than those forming nodules on lucerne.

A calibration equation for NIRSystems 6500 instrument was derived at VSTE Jevíčko using the measurement of broad collection of Czech samples of winter rape, allowing sufficiently accurate prediction of content of dry matter (DM), crude protein (XP), crude fat (XL), glucosinolates (GSL), oleic and linoleic acids in an extremely short time. The prediction accuracy was verified on a validation file (n = 60). The coefficients of determinance (R2) were 0.83 for XP, 0.71 for XL, and 0.84 for GSL. The prediction accuracy according to the VSTE equation was compared to the prediction accuracy according to the VDLUFA calibration equation (Kassel, FRG) used in EU near infrared spectroscopy network. It was stated that the former was not distinctly worse. Non-destructive NIR-analysis of the whole seed also allows sowing selected seeds in the year of harvest and thus accelerates the breeding cycle.

Results of scoring the resistance of 35 selected spring barley varieties to powdery mildew, exhibiting high powdery mildew severity, in 307 variety trials of the Central Institute for Supervising and Testing in Agriculture were analysed. The varieties can be divided into two groups: the varieties that could not induce any changes in the pathogen population (the varieties with no effective resistance gene and varieties carrying gene mlo) and the varieties possessing major resistance genes [a total of 12 Ml-genes: a1, a3, a6, a7, a9, a12, a13, at, k1, La, g and (Kr)] to which the pathogen population adapted in 1971-2000. The time slope of decreasing resistance of varieties is described. The importance of individual evolutionary forces (mutations, migration, direct selection, indirect selection and recombinations) for the erosion of efficiency of respective major resistance genes and the effects of pathogen adaptation on population complexity and diversity are discussed.

The effects of different tillage systems and dose reduction on the efficacy of triasulfuron & chlortoluron mixture in the post-emergence control of annual broad-leaved weeds in winter wheat and spring barley were studied on lessive pseudogley soil in north-eastern Croatiaduring 1997-2000. Total dry biomass production in untreated plots was significantly influenced by tillage and it was lowest in continuous mouldboard ploughing (99 kg/ha), medium and similar in mouldboard ploughing/disk harrowing alternating every second year and in chisel ploughing (218 kg/ha) whereas the biomass was highest in continuous disk harrowing (422 kg/ha). Thereby the proportion of annual broad-leaved weed biomass was 70, 63, and 28%, respectively. Chenopodium album L., Ambrosia artemisiifolia L., Ch. polyspermum L. and Polygonum aviculare L. are the most abundant annual weed species in all tillage treatments. One half and one quarter of the recommended rate decreased the control efficacy of total weed biomass by 12 and 19%, respectively in wheat and by 6 and 15%, respectively in barley compared to the highest dose but they still provided a very good biomass control of main annual weeds (94-96 percentage units). The efficacy of reduced herbicide doses in the control of annual broad-leaved weeds did not vary significantly between tillage treatments and growing seasons. Significant interaction with continuous disk harrowing tillage and one-quarter herbicide dose was detected in the last year of wheat trial when perennial weeds increased their biomass proportion 8 times compared to four years before.

The Pb, Zn and Cd phytoextraction potential of 14 different plants was assessed in a chelate induced phytoextraction experiment. In the used soil heavy metals mainly reside in carbonate, organic matter, and residual soil fractions. The addition of a chelate, 5 mmol/kg ethylenediamine-tetracetic acid (EDTA), increased the proportion of phytoavailable Pb, Zn and Cd in the soil (dissolved in soil solution and exchangeable from soil colloids), and also their uptake by tested plants up to 48 times (Sinapis alba), 4.6 times (Raphanus sativus oleiformis), and 3.3 times (Amaranthus spp.), respectively, compared to the control. The biodegradable chelate ethylenediamine-disuccinic acid (EDDS) was generally less effective (tested on a selection of 4 plant species), except for Cannabis sativa. In a treatment with 10 mmol/kg EDDS, Pb, Zn and Cd concentrations of 1053 ± 125, 211 ± 16 and 5.4 ± 0.8 mg/kg, respectively, were measured in the biomass of Cannabis sativa and were 105, 2.3 and 31.7 times higher, respectively, than in the control treatment. The calculated Pb phytoextraction potential of Cannabis sativa amounted to 26.3 kg/ha.

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

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

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.

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

The level of the usage of information and communication technologies (ICT) has a direct influence on the development and competitiveness of individuals, firms, production sectors, regions and even the whole continents. The availability of ICT, including the Internet, to agricultural enterprises in theCzechRepublicis already very satisfactory. Due to the structure of agricultural enterprises the penetration of Internet technologies in theCzechRepublicis more intensive than in most EU countries. Therefore an urgent issue is the level of the usage of these technologies that is not an issue related to finances anymore but it is a problem related to the knowledge and habits of users and availability of information and services. The project of the portal for the agriculture sector and countryside AGRIS has a significant impact on the level of the usage of Internet information and services in the agriculture sector.

Numerous agricultural and associated ecological effects such as mineral nitrogen fertilising influence the yield of hop (Humulus lupulus L.) cones and its quality. Using a wide spacing of plants (in our case 2.6 × 0.8 m) we want to answer a hypothetical question about an appropriate number of test plants per plot vs. experimental plot area. The aim of this study was to compare the effect of different rates of mineral nitrogen, fertiliser combinations and their nitrogen split application on hop yield evaluated from different plot areas (micro trial: 30 plants per plot; macro trial: 320 plants per plot). Hop yield varied significantly between treatments, plot areas, years and interactions (year × treatment, plot area × treatment) (all at P £ 0.01). Cone yield in a micro trial was higher in all treatments in comparison with yield in a macro trial. In spite of common intensive fertilisation the appropriate fertilising combination and mineral N rate can influence the yield. Target nitrogen rate of160 kg mineral N/ha (at the level from 40.0 to62.5 kg nitrate N/ha in soil depth to0.3 m) and cheaper combination of calcium-ammonium nitrate (50 kg N/ha) at the beginning of vegetation plus urea (110 kg N/ha) for top dressing can be recommended. On plot areas of each size and each year all treatments showed similar trends of fertilising effect on yield. In spite of higher yield in the micro trial and lower coefficient of variation in comparison with the macro trial, the results proved that a risk of incorrect yield analysing in macro trials is very low for field experiments.

A five-year study was conducted to study the correlations between chemical analyses and sensory properties of wine during bottle aging. Chardonnay grapes were harvested as a normal and late harvest. After separate vinification, bottles were put in an underground cellar at12°Cand 75% of humidity. Chemical and sensory analyses were carried out after bottling (0), after 12, 24 and 36 months of bottle aging. The results of chemical and sensory evaluation show a strong correlation between a young wine bouquet and decrease in the concentration of isoamyl and 2-phenethyl acetates, and between an increase in diethyl succinate and bottle bouquet.

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

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 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.

The influence of an interrupted K fertilisation on different K fractions of the soil, yield formation and K uptake by different crops was investigated in a long-term field experiment on Luvisol derived from loess. Irrespective of the previous K fertilisation, the interruption of K fertilisation resulted in a sharp decline of CAL extractable K. K concentration in the saturation extract as well as HCl extractable K were reduced while K fixation capacity increased within 10 years after omitting K. Omitting K fertilisation decreased yields of sugar beet and potatoes while cereals were not affected, although K uptake of all crops reacted to the differentiated K supply to a different extent.

Long-term field experiments conducted under different soil and climate conditions and their databases provide invaluable information and are indispensable means in the study of the productivity and sustainability of the soil management systems. We evaluated the results of the dry matter yields of the main products obtained with four variants of organic and mineral fertilisation in three long-term field experiments established in 1955. The experiments differed in the cultivated crops. The period of evaluation was 12 and 16 years (1985-2000), respectively. The productivity of nine-year crop rotation was lower with the fertilised variants than that with the alternative growing of spring wheat and sugar beets. The dry matter yields on the Nil variants, however, were higher in the crop rotation than in the alternate sugar beet and spring wheat growing, apparently due to the symbiotic nitrogen fixation. The dry matter yields of sugar beet and mainly of spring wheat declined in almost all variants of fertilisation in the alternate sugar beet and spring wheat growing, over the evaluated time period. In spite of the relatively high dry matter production, the declining yields indicated a lower sustainability of the alternate cropping system. Both organic and mineral fertilisation increased the production of the cultivated crops. The differences in the average dry matter yields were statistically significant. Both organic and mineral fertilisation enhanced significantly the N-uptake by the cultivated crops. The effectivity of nitrogen input was the highest with the alternate cropping of sugar beet and spring wheat indicating that it was more demanding for the external N-input and thus less sustainable than nine-year crop rotation.

During the years 1998-2000 soil chemical (C_org, N_t, pH), textural (sand, silt clay) and microbiological (microbial biomass carbon - CMB, microbial extracellular carbon - C_EX, respiration, ammonification, nitrification) characteristics were tested on grassed chernozem [mollisol] after arable land setting-aside. Different harvest management was also tested: black and green fallow, one or two mulching per year, three cuts with plant biomass removal. For the evaluation of the influence of management and plants we have used three main criteria: (1) µg C_MB/g dry soil, (2) ratio CMB/C_org (%), (3) µg C_EX/mg CMB or eight criteria respectively: (4) ratio of measured and model values of C_MB, (5) ratio of measured and model values of C_EX/C_MB, (6) potential respiration with glucose, (7) potential ammonification with peptone and (8) potential nitrification with (NH₄)₂SO₄. According to these criteria, the best harvest management after arable land setting-aside from 5 different systems, which were tested, could be based on one or two mulching per year. It could be stressed that the two mulching was evaluated as the best in sum of dry mass yield (27.5 for mixtures, 20.1 for legumes and 14.2 for grasses - in t/ha/3 years). The use of legumes (Trifolium repens L. - Medicago lupulina L. - Lotus corniculatus L. - Medicago media Pers.) or grasses [Bromus catharticus Vahl - Arrhenatherum elatius (L.) Presl - Festuca pratensis Huds - Dactylis aschersoniana Graebn.] as cover plants was more successful than the use of their mixtures.

In the case of cadmium transport via soil macropores, the short-term duration of an interaction between the reactive solute in aqueous phase and soil, as well as cadmium precipitation or adsorption on particles < 10-5 m should be taken into account. Two distribution coefficients are proposed for predicting the cadmium transport in a structured soil: the matrix distribution coefficient Kdm, equal to the equilibrium distribution coefficient Kdeq and estimated using the conventional batch technique, and the macropore distribution coefficient KdM, estimated using the modified batch technique. It was found that the conventional approach (using the coefficient Kdeq only) would underestimate a penetration of the part of Cd transported in the macropores about 255-times in the loamy-sand soil in Kalinkovo, 20-times in the loam soil in Macov, and 122-times in the clay soil in Jurová in comparison with the approach proposed in this study.

In 1999, the effect of increasing levels of nitrogen at the initial (13.9 mg.kg^-1) and increased (40 mg.kg^-1) level of watersoluble sulphur (S_wat) was studied in winter rape (cv. Lirajet) grown in pots. A synergetic effect of nitrogen on concentrations of Ca and Mg was demonstrated in the growth stages DC 20-29 and 31-39. Levels of P and K were balanced. In variants with a low content of S_wat in soil to 40 mg.kg^-1 of soil S concentration increased. With the increasing dose of N the content of S decreased from 1.00% to 0.78% and from 0.68% to 0.38% in DC 20-29 and DC 31-39, respectively. An increased level of S in soil changed the ratio N/S. In variants with a natural (i.e. low) content of S in soil, this ratio widened with the increasing dose of N from 8.06 to 25.15 while in variants with an increased level of S in soil it ranged from 3.24 to 5.85 in the growth stage DC 20-29. Increasing doses of N widened the ratio N/P regardless to concentration of S in plants. In individual growth stages the ratio P/S was markedly narrowed by changing contents of S in soil. The highest yields were obtained in the variant with an optimum concentration of all elements in plants and S contents above 0.6% and/or about 0.4% in growth stages DC 20-29 and DC 31-39, respectively. The obtained yields demonstrated a highly significant effect of N and S on seed yields. At a low concentration of sulphur in plants the yield of seed increased only to the dose N₃(i.e. 0.9 g N per pot); thereafter, it gradually decreased. An increased level of S in soil showed a positive effect on seed yields. Higher doses of N widened the ratio straw/seeds from 2.46 to 7.69; at higher levels of S in soil, an opposite trend was observed. In variants with a low content of S the number of branches and pods increased proportionally with increasing doses of N. On the other hand, increased levels of S reduced the number of branches and pods. At a low level of S in soil the total weight of seeds per pod decreased with the increased supply of N from 69.9 mg to 20.4 mg. At increased levels of S the weight of seeds per pod increased from 61.9 mg to 79.8 mg. Results of field experiments in four different localities corroborated a positive effect of S (in interaction with N) on its concentration in plants. The seed yield was significantly increased. In 2000, results from all localities were markedly influenced by climatic conditions; however average results of all experiments showed that S increased seed yields depending on the dose of N by 2.5 and 5.9%. An optimum nutrition of plants with all elements (including S) results in improved utilisation and increased yields.