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

In the years 1999-2000, I studied damage to transplants in the planting and wildlings in the natural seeding at the locality Zamrlô in the Starohorské vrchy Mts. (750-1,000 m a.s.l., NE exposure, forest type Abieto-Fagetum). Damage to the woody plants by the mammals and birds in the planting was much higher (14%) than in the natural seeding (7%). All woody plant species were also more damaged in the planting (spruce 16%, larch 9%, fir 24%, beech 10%, and sycamore 10%) than in the natural seeding (spruce 7%, larch 6%, fir 10%, beech 7%, and sycamore 9%). There were found 8 mammals that damaged woody plants both in the planting and natural seeding (Apodemus sp., Capreolus capreolus L., Cervus elaphus L., Clethrionomys glareolus SCHREB., Lepus europaeus L., Microtus agrestis L., Microtus arvalis PALL., Sciurus vulgaris L.). Only one bird species was found to damage woody plants in the planting and natural seeding (Tetrao urogallus L.).

The general outcomes of long-term trajectories of coevolutionary interactions between specific hosts and pathogens areset by the interaction of their life histories. However, within those outcomes the speed of co-evolutionary responses andthe extent of their expression in the resistance/virulence structure of wild plant and pathogen populations respectively,are highly variable characters changing from place-to-place and time-to-time as a result of the interaction of host andpathogen with the physical environment. As a consequence, understanding of the role of diseases in the evolution of theirhosts requires approaches that simultaneously deal with host and pathogen structures over multiple populations within ametapopulation framework.

The effect of fluridone (or flurochloridone), the inhibitor of carotenoid, chlorophyll and abscisic acid synthesis, on the abscission of Ligustrum vulgare leaves was investigated. Both forms of fluridone inhibited the abscission of petioles when they were applied as a 1.0% concentration in lanolin to the leaf blade. Fluridone was capable of inhibiting abscission even when it was applied to the petiole as late as 7 hours after the blade was cut off. Fluridone applied in lanolin to the apical part of intact pea seedlings or on the cut surface after decapitation of the epicotyl caused albinism of the stipules. The degree of albinism decreased according to the concentration of applied flurodine (from the highest - 0.5% to the lowest - 0.03%) and was higher in intact than in decapitated plants. Albinism also appeared in pea seedlings grown from seeds swollen in differently concentrated solutions of flurochloridone, particularly in the basal part of the shoots. Complete albinism occurred only in plants cultivated from seeds swollen in high concentrations (0.06-0.12%). The lowest concentration (0.007%) stimulated root growth of the pea seedlings, but inhibited epicotyl growth.

Problems concerning total dry weight and distribution of underground phytomass were studied in a pasture trial at Rapotin near Šumperk, the CzechRepublicin the period 1995-1999. The total weight of dry underground pasture phytomass (DUP) was 976 g/m² (5-year average) in a soil layer of 0-200 mm (both live and dead roots). The DUP was significantly increased by mineral fertilizers (90 kg N/ha, 30 kg P/ha a 90 kg K/ha). The weight of DUP was not significantly influenced by a grazing system, renewal or resowing of the original grassland. In unfertilized plots, DUP weight amounted to 989 g/m², i.e. 92 g/m² (8.6%) less than in fertilized plots in the period 1996-1999. In the same period, under the grassland exploited by rotational grazing 1142 and under continuous grazing 1082 g/m² DUP were determined, i.e. by 60 g/m² (5.5%) less. The highest DUP weight in the period 1996-1999 was found in autumn 1997 (1222 g/m2) immediately before achieving the maximum forage yield in May 1998. In a layer of 0-20 mm, 54.6% of the total DUP was found. In this surface layer, significant increase in the DUP weight was found in fertilized plots. In 1999, some 88.5 and 90.2% of DUP were concentrated in unfertilized (903 g/m²) and fertilized (952 g/m²) plots, respectively in a layer of 0-100 mm.

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 objective of the paper is taxonomic evaluation of a woodland grape individual found near the Dyje river. The finders (Vicherek et al. 2000) determined the liana as Vitis vinifera subsp. sylvestris. Based on microscopic observations of bud sections some doubts were cast on the classification to the subspecies of sylvestris. Correct determination will be possible only on the basis of further observations of the found individual and its comparison with real members of the taxon (Čenkov, SR).

In this study the aggressiveness of nine isolates of P. infestans was determined using detached leaflets from cultivars Bintje and Stirling. The growth of the isolates on the leaflets was recorded on a daily basis, for seven days, and an assessment of their aggressiveness could then be made. Extracellular preparations (ECPs) from the zoospore suspension of each isolate were used as a source of proteolytic activity. The ECPs were found to contain a level of serine protease activity using BTEE (N-Benzoyl-L-Tyrosine Ethyl Ester) as a substrate and recording the absorbance at 256 nm. The possible relationship between the serine protease activity and the aggressiveness of the isolate is discussed.

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.

Partial characterization of iron binding compounds in spinach above ground biomass and differences between binding of Cd, Zn and Fe in spinach biomass were investigated on two soils treated by sewage sludge in model pot experiment. After application of sludge to both soils, Cd and Zn accumulation in spinach biomass was increased in sludge treatments. Total Fe content in biomass showed opposite trend with these treatments and was decreased 2.5-2.7 fold. Results of sequential analysis of spinach biomass showed lower portions of iron in all individual fractions of both sewage sludge treatments compared to control treatments. The largest differences in iron content between control and sludge treatments were determined in ethyl acetate fraction. While majorities of Cd and Zn were found in fractions methanol + H2O and H₂O and methanol + H₂O + HCl, iron content determined in these two fractions was only 7-8% in control treatments and 15-20% in sludge treatments of total iron. In fraction, Fe portion was 87.7-90.7% in treatments without sludge and 76.1-83.5% in sludge treatments in spinach biomass. Results showed tighter iron binding to plant cell membranes in contrast to cadmium and zinc.

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.

BORM (Business Object Relationship Modelling) is a methodology developed to capture the knowledge of process-based business systems. It has been in development since 1993 and has proved an effective method, which is popular with both users and analysts. This paper presents BORM, its tools, and methods via a case study of the agrarian information system. BORM is based on the combination of object-oriented approach and process-based modelling. Also, an advantage of BORM is the small number of concepts required combined with a considerable expressiveness. In this way, BORM is in the tradition of pure approach established over the past years by structured modeling techniques.

Using Moericke's yellow dishes we studied the Hymenoptera (Aculeata) fauna (with the exception of Formicoidea) in spruce (Picea abies) stands of the colder region of Northern Bohemia. We collected 103 species and the most important species in this spectrum were Vespula vulgaris (56.4%), Vespula rufa (4.7%), Dolichovespula norvegica (3.1%), Dolichovespula saxonica (4%), Nysson spinosus (1.8%), Andrena lappona (1.9%), Cleptes semiauratus (5.9%), Halictus sp. (6.7%) and Trypoxylon minus (2.2%). Comparisons made in 1990-1994 and 1995-1999 indicated a recession of species of the genus Halictus, of Andrena nitida (Apidae), Pemphredon lugubris, Trypoxylon clavicerum and T. minus (Sphecidae), and an increased abundance of Cleptes semiauratus (Cleptidae), Nysson spinosus (Sphecidae), Vespula vulgaris and V. rufa (Vespidae). Compared to closed stands, open spruce stands had a greater species diversity and lower number of captured specimens.

A translocation from Aegilops ventricosa carrying genes Yr17, Lr37 and Sr38 was verified in cultivars Hussar, Eureka, Torfrida, Renan, Rendezvous, Rapier and Brigadier by the molecular marker SCARSC-Y15. Of the cultivars recently registered in the Czech Republic, only the western European cultivars Corsaire, Apache, Complet and Bill possessed the translocation carrying Yr17, Lr37 and Sr38. Cultivars Corsaire, Apache, Bill and Complet were highly or medium resistant to yellow rust and leaf rust in 1999-2001 field trials at Prague-Ruzyně, although virulence to Yr17 was found in the 2001 virulence survey also in the Czech Republic. Cultivars Corsaire, Apache and Bill displayed an above average resistance to stem rust, whereas Complet was susceptible.

Changes in N-NO3- content and N-NO3- increase after incubation were studied in 1992-1998 in soils of two farms situated in identical soil and climatic conditions (in spring and autumn seasons). The two farms produce sugar beet and grain crops, but since 1991 they have used different types of organic fertilizers. Farmyard manure has regularly been applied to root crops on Dobrá Voda farm; since Chvalina farm does not have animal production, green manure and plowing-in of beet tops and straw are used for organic fertilization. Soils with regular applications of farmyard manure show a trend of lower N-NO3- content than the soils of the farm without animal production. At Dobrá Voda N-NO3- content was about 12 ppm N in spring and 9 ppm N in the autumn season while the respective values for Chvalina were 14 and 10 ppm N. On the hand, N-NO3- increase after soil incubation (12-14 ppm N) was higher in Dobrá Voda soils than in soils from Chvalina farm (5-8 ppm N).

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 new method for evaluating damage caused by tenthredinids to Norway spruce stands is based on defoliation of the top whorls. A scale with four classes of defoliation was established that is easy to use. Defoliation can be displayed graphically on a grid map (Central European system), in which the map fi elds are delimited by parallels of latitude (6 by 6 minutes) and meridians (10 by 10 minutes) with an approximate size of 11.2 × 12.0 km. The degree of defoliation for an entire forest can be marked by circles of different size in the map field. The range and intensity of an infestation, and the change in defoliation from year to year are easily seen.

Postharvest biocontrol activity of CaC_l2 and four yeasts against Penicillium digitatum was tested on Tarocco oranges. All tested organisms (Pichia anomala J121, Pichia guilliermondii NRRL Y18314, Debaryomyces hansenii DBVPG 4025 and Saccharomyces cerevisiae P1.6) significantly reduced mould incidence and severity. Application of CaCl₂ enhanced biocontrol efficacy of P. guilliermondii and S. cerevisiae, while it did not significantly affect biocontrol of P. anomala and D. hansenii.

A model experiment was conducted to compare hand extraction (elutriation) under running water and elutriation using the device Analysette 3, the two methods for estimation of weed seedbank in the soil. Technical parameters have been assessed for efficient operating of the device. We studied the time required for elutriation of soil samples and the time for collecting, counting and identifying the separated seeds. No significant difference in the effect of the used elutriation method on results of qualitative and quantitative estimation of weed seedbank densities has been found at any of the three locations differing in soil texture (silty loam, loam and clay loam soil). The time necessary for elutriation of soil samples was highly significantly shorter if the device was used, by 35.5 to 42.9% depending on soil texture vs. hand elutriation. The shortest time was assessed for silty loam soil. By contrast, the time needed for selecting, counting and identifying seeds was shortest for clay loam soil. This time was 46 and 92% longer for loam and silty loam soil, respectively. These differences were statistically highly significant. Comparing the seedbank in the soil, a significantly lower number of weed seeds as well as species was found on silty loam soil vs. the two locations with heavier soils. Amaranthus retroflexus was a dominating species at all locations, and on silty loam soil also Chenopodium album. Of a total number of 32 weed species detected in our experiment, 28 were annual and only four perennial (Cirsium arvense, Elytrigia repens, Rumex obtusifolius and Sonchus arvensis).

The objectives of this study are to determine the relationship between crown characteristics and the radial increment of beech (Fagus sylvatica L.) and to specify the characteristics of beech trees with the radial increment above the average in the Świętokrzyski National Park. The following relationships have been found: the radial increment of beech increases as the degree of the freedom of the light part of the crown from neighbouring trees increases, and the increase in the relative crown length causes a significant increase in the radial increment. Most of the best growing beech trees are characterized by the light part of the crown confined in an area of up to about 55%, and the relative crown length spanning the range of 55% (trees 61 to 80 years of age at b.h.) to 76% (trees 21 to 40 years of age at b.h).

The main goal of this work was to calibrate and evaluate the CERES-Barley and CERES-Wheat crop models. The experimental fields used for the model evaluation are situated in three different production regions (maize, sugar beet and potato main growing regions, respectively) with altitudes of 179, 204 and 560 meters above the sea level. Grain yield and date of anthesis together with maturity dates served as reference for the model evaluation. Two evaluation approaches were tested in this study. The first one uses historical data series and it is based on long-term field experiments with capability to reflect interannual weather variability. The second approach uses results of one-year multiple treatment experiment. The model evaluation is then based on a set of treatments differing e.g. in sowing date or an amount of used nitrogen fertilizer. Grain yields simulated by both models are acceptable when compared with experimental results: the coefficient of determination for historical series varied from 0.69 to 0.86 for evaluation of CERES-Barley at the three examined sites and reached values of 0.60 and 0.86 for the CERES-Wheat model at two experimental sites. The lower coefficient of determination of the wheat model was recorded at the locality with the highest altitude and coldest winter conditions. There, also the worst reliability of simulated phenological development was noted. At the second locality where the CERES-Wheat model was tested and at all three localities where CERES-Barley was applied, the simulated duration of vegetation period and anthesis dates were relatively accurate and yielded strong statistical correlation. The one-year multiple treatment experiment proved to be useful to determine the models sensitivity to differences in crop management. The combination of both approaches seems to be the best solution for evaluation of similar crop models if the detail long term experimental data are not available.

The laboratory incubation with glucose treatment was carried out in order to estimate the possible effects of increased microbial activity on heavy metal availability. The soils from vicinity of a lead smelter operating for more than 200 years were used for the experiment. The DTPA-extractable heavy metal contents increased after glucose addition and mostly reached the highest values the second day of the incubation. The comparative study, where the chloroform fumigation was used prior to the incubation in order to decrease the microbial activities, showed especially from second day of incubation significantly lower DTPA-extractable metal contents compared to non-fumigated treatments. The interactions among the maximum possible availability of DTPA-extractable heavy metal fractions and native soil microbial characteristics were studied in differently contaminated arable and grassland soils. Irrespective of different heavy metal contents in soils, significant correlations were found among the maximum percentage increase of DTPA-extractable Pb and Cd and the ratio Bc/TOC and metabolic quotient (qCO₂) which may be a result of the important role of organic matter and microbial characteristics in soils on the heavy metal availability.

This paper evaluates the development of growing stock, number of trees and diameter distribution of the standing volume in the Opuky locality where conversion to a selection forest has been the aim of management over a long period of time. With respect to species composition, the stand is divided into two plots. The initial condition and development of both plots differed. The favourable initial composition of the stand has gradually deteriorated due to delay in natural regeneration and therefore recruitment of young trees over a long period. The total number of trees on both plots has been low for target diameter of 51 cm. On the other hand, the growing stock has exceeded the model condition. The proportion of broadleaved species in the stand gradually increases, reducing the possibility of conversion to a selection forest in future.

Height and diameter growth and volume production of 22 different clones of poplars were evaluated in Sliepkovce populetum at the age of 12 years. The populetum is situated on medium-heavy and medium humic uninundated alluvia of the Laborec river; typologically, the group of forest types is Ulmeto-Fraxinetum populeum. The results of evaluation documented that among the poplars under study the clones Gigant, OP-229 and BL achieved the best growth and maximum volume production while their mean height amounted to 22.9-23.8 m, mean diameter to 31.9-33.2 cm and average annual volume increment was 25.1-28.3 m³ per 1 ha. The growth of P. Rochester 20/66 poplar was considerably much slower: its mean height amounted to 17.3 m, mean diameter to 18.7 cm and average annual volume increment was 6.3 m³ per 1 ha. It will be necessary to carry out further studies to obtain more detailed values for these clones.

Commercial orange juices samples obtained from the Czech market were analysed in the years 1996-2001. The quality and authenticity of samples was evaluated according to the Code of Practice of AIJN (selected main analytical criteria were followed - K+, Na+, Ca2+, Mg2+, citric, isocitric and malic acid, citric acid/isocitric acid ratio, glucose, fructose, saccharose, sorbitol, formol number, flavonoid glycosides - according to Davis and HPLC procedure, refractive index and other). The approach of producers to the quality and authenticity of juices developed during the years of observation. The main cases of adulteration in 1996 were as follows: (i) lower fruit content in juice, (ii) massive addition of sugars masked with addition of citric acid, (iii) several examples of "synthetic" orange juice were found. In the subsequent years the authenticity slightly improved, the main problems in 2000/2001 were: (i) lower refractive index, (ii) pulp wash addition, (iii) lower quality of water used for juice reconstitution, (iv) undeclared addition of sugar. The deviations were found not only in the case of the juices of Czech producers, but also in several discount and low-end products of foreign producers. Possible ways of improving the quality and authenticity are discussed (e.g. the preparation of a Czech National Standard taking over the requirements for juices and nectars according to the Code of Practice of the AIJN, Participation in the European Quality Control System [EQCS], etc.).

The genus Armillaria belongs to basidiomycetes and has been known to induce root rot disease and to cause extensive economic losses to a forest crop. We analysed about 40 isolates of Armillaria collected in Czech Republic by PCR and restriction analysis using gel electrophoresis and ion-exchange HPLC. Restrictase Hinf I was able to discriminate all investigated Armillaria species. The sensitivity and resolution of HPLC method was better than that performed by gel electrophoresis. HPLC was able to detect some heterozygous. The results prove the similarity of the species A. borealis, A. cepistipes, A. gallica, A. ostoyae in difference of A. mellea and A. tabescens.

A scanning electron microscope study of citrus fruits was performed to assess the colonization process of antagonistic yeasts to green mould of Tarocco oranges under artificial inoculation. Yeast suspensions of Debaryomyces hansenii DBVPG 4025, Pichia guilliermondii NRRL Y 18134, P. anomala J121 and Saccharomyces cerevisiae P1.6 with or without addition of 1% CaCl₂ + 0.1% Tween 80 were evaluated. Penicillium digitatum was sprayed one hour later. Observation of fruit surface waxes revealed marked morphological diversity. Yeast cells and conidia were mostly localized on epicuticular waxes, particularly in naturally occurring small pits. The size of the wound affected the number of yeasts and conidia penetrating inside. Treatment with CaCl₂ did not affect the waxes and/or the behaviour of the yeasts and pathogen.

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.

Resistance associated with a hypersensitive response (HR) and subsequent development of necrotic lesions (cell death) at the sites of virus infection can restrict virus movement in plants. Genes for HR are dominant and act on a gene-for-gene basis. Many viral proteins triggering HR have been identified. Also, several genes for HR-based virus resistance, or virus-induced cell death without resistance, have been isolated and characterized in plants, which provides novel insights to the mechanisms of virus resistance. Another international, major research frontier has formed more recently around RNA silencing, a universal RNA surveillance system and inducible virus defence mechanism in multicellular organisms. Many viral proteins interfere with different phases of RNA silencing. The data provide novel insights to break-down of resistance in mixed virus infections (viral synergism), resistance to virus movement, and recovery of plants from virus infection.

The fertilising experiment was set up in 1968 on the mountain meadow (720 m a.s.l.) in Czarny Potok near Krynica (20°8' E, 49°4' N). The experiment was conducted on the acid Cambi soil and comprised objects fertilised with two nitrogen forms and two doses against the background of PK fertilisation, the untreated object, and plots with unilateral P and N fertilisation. The paper concerns 30 years of investigations (1968-1997) of the effect of different NPK fertilisation on the dynamic of yields and the meadow sward quality against a background of the same treatments. The dynamic of the botanical composition was presented as well as the dynamic of the grassland yield potential with systematic mineral fertilisation and liming. The application of nitrogen fertilisation with the rate of 90 N.ha^-1 + PK under mountain conditions and systematic liming of the meadow enables to maintain or increase production over the long period, to decrease the production risk and to prevent degradation of the environment and natural resources.