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This paper is aimed to investigate the effects of some terricolous lichens on soil bacteria's growth in natural conditions. It is focused on species of bacteria and also on numbers of colony of soil specimens that were taken from substrates of three different terricolous lichen species. Peltigera rufescens (Weiss) Humb., which has not secondary metabolites, did not show an inhibition effect on soil bacteria. However, Peltigera neckerii Hepp ex Müll. Arg., which has secondary metabolites, has a negative effect on soil bacteria's growth. Besides, it was observed that Cladonia rangiformis Hoffm., which has many kinds of secondary metabolites, has the highest inhibition effect among the studied species. For this reason, we think that in the next researches, it is convenient to investigate elaborately by soil analysis the effect of lichen's secondary metabolites that have an effect on soil mineralization, on soil bacteria's growth.

Changes in root anatomical structures at successive cycles of selection (cycle 1 to cycle 18, alternating) were observed in the study of maize (Zea mays L. cv. Saracura-BRS 4154) capable to survive and produce in temporarily flooded soils; this cultivars was developed by the Maize and Sorghum National Research Center through stratified phenotypic recurrent selection for cultivation wetland soils. Field trial was carried out and flooding of the soil was initiated at the six-leaf stage; the soil was flooded with water (20-cm deep) three times per week. Root sample was collected, fixed, and selected for observation in photon microscope. A gradual increase in the number of aerenchyma, the proportion of vascular cylinder, smaller metaxylem, and phloem and epidermis width, and a decrease in exodermis and cortex were observed in successive selection cycles. Such phenotypic changes impart the flood tolerance ability to this maize cultivar.

: A glasshouse pot experiment tested the effects of 14 different combinations of substrate type, pH and nutrient treatments on the occurrence and severity of leaf chlorosis in a susceptible variety of petunia. Plants grown at optimal pH level (4.7) in peat substrate with low limestone dose were symptom-free even without added micronutrients. Severe chlorosis occurred in plants grown at high pH in peat substrate with high limestone (pH 6.7) and in peat-bark-compost (pH 6.2); it was associated with decreased Fe and Mn content in leaves. Regular application of nutrient solution with low concentration of Fe, Mn, and other micronutrients as EDTA chelates greatly reduced chlorosis in plants grown in peat-bark substrate and in peat-bark-compost, and it improved Fe uptake. An exception was peat substrate at high pH level and high limestone where chlorosis was only partially reduced by this treatment. Regular application of Fe, Mn, and other micronutrients as sulphates or citrates had no substantial effect; only application of three additional substrate drenches of 30 mg/l Mn from Mn-EDTA and 90 mg/l Fe from either Fe-EDTA or Fe-EDDHA substantially corrected chlorosis and increased foliar Fe and Mn in cases where plants were grown in high limestone peat substrate.

The paper deals with the use of European beech in the reconstruction of substitute species stands and in the regeneration of existing spruce stands in the air-polluted region of the north-eastern Krušné hory Mts. (air-pollution damage zones A, B, forest altitudinal vegetation zones 6 and 7, acidophilic sites). Twenty stand situations were analyzed during the study. The study objective was to compare the growth of European beech plantations in the Krušné hory Mts. with the growth of plantations of the same age in similar sites in the unpolluted region of the Bohemian-Moravian Upland (air-pollution damage zones C, D, forest altitudinal vegetation zone 6, acidophilic site). Each plant was assessed for eight growth and visually classified parameters and traits. Results of the survey showed that in the existing air-pollution and climatic situation, it is possible to switch to normal (shelterwood) beech management of higher elevations in the north-eastern Krušné hory Mts. The stands of substitute species and the current stands of Norway spruce may effectively eliminate injuries caused by late frost.

The article discusses economic development of Slovak agriculture in the period after the accession of Slovakia to the EU and after adopting the CAP. It evaluates agriculture as a whole and its contribution to the national economy, as well as the economic performance of the individual legal forms of business and production sectors. The results achieved by agriculture in 2004-2007 suggest that the income within the sector (except of 2005) has improved also due to the inflow of the EU subsidies. On the other hand, despite the growing aid the production output is shrinking, wages stagnate and the employment is falling. This suggests that the CAP should be changed after 2013, especially as regards the ways of subsidy payments. Economics of the individual products are largely affected by input prices, realisation prices, as well as by the volume of direct subsidies, namely in the plant production - the subsidies for crops grown on arable land, and in animal production - the subsidies per 1 Big Cattle Unit.

The influence of application of increasing doses of selenium (0.05 mg, 0.10 mg and 0.20 mg/kg) into soil in pot experiments, with NPK fertilization of spring wheat (Triticum aestivum L., variety Banti), on the biomass yield (grain, straw, roots) and on selenium accumulation was observed. Selenium in the form of sodium selenite (Na₂SeO₃*5H₂O) and the NPK nutrients in the form of LAD-27, Ca(H₂PO₄)₂ and KCl were applied. The average two-year results showed the expected indifferent effect of increasing doses of selenium on the yield of wheat grain, straw and roots. The differentiated doses of selenium into soil caused a significant increase of selenium content in dry matter (dm) of grain, straw and roots of wheat. The highest content of selenium (0.732 mg/kg in grain, 0.227 mg/kg in straw and 1.375 mg/kg in roots dm) was determined in the variant where 0.2 mg Se/kg of soil was applied. When applying the lowest dose of selenium (0.05 mg Se/kg of soil) the content of selenium was 0.155 mg Se/kg in grain. The selenium content in individual analysed parts of wheat was increasing in the following order: straw - grain - roots.

Microarray analysis is a cultivation-independent, high-throughput technology that can be used for direct and simultaneous identification of microorganisms in complex environmental samples. This review summarizes current methodologies for oligonucleotide microarrays used in microbial ecology. It deals with probe design, microarray manufacturing, sample preparation and labeling, and data handling, as well as with the key features of microarray analysis such as specificity, sensitivity and quantification potential. Microarray analysis has been validated as an effective approach to describe the composition and dynamics of taxonomic and functional microbial communities, in environments including soil, compost, sediment, air or humans. It is now part of the technical arsenal available to address key issues in microbial community ecology, ranging from biogeography to ecosystem functioning.

The aim of the paper was to analyse congenital disorders in the Czech cattle population in 1986-2001. The offspring of 474 sires - 215 Czech Simmental, 236 Holstein, and 23 beef - were diagnosed with congenital disorders which were unevenly distributed because only 18 occurred in the progeny of 10 and more sires, in contrast to 88 occurring in the progeny of 1 sire only. Umbilical hernia was the most frequently noted disorder, and 136 sires fathered progeny with limb anomalies. The most frequent gestational accident was schistosomus reflexus, the results suggesting a familial burden. Three sires fathering offspring with the afflicted spinal column and limbs were heterozygous for Complex Vertebral Malformation (CVM) though they had not been reported as such. Foetal defects and stillbirth were quite frequent, and the calves affected were fathered by 56 sires. In rare disorders with a low incidence, an accurate genetic analysis or even simple discrimination between inherited and acquired defects is problematic. It would be our recommendation that those sires with a higher incidence of defects among their offspring should be disqualified from fathering stock bulls, or culled.

The aim of the present study is to understand the hormonal mechanisms of the effect of malnutrition on ovarian follicle functions. For this purpose, we examined the effect of malnutrition/serum deprivation, addition of metabolic hormones and gonadotropin (IGF-I, leptin and FSH) and their combination on the release of progesterone (P₄), testosterone (T), estradiol (E₂) and insulin-like growth factor I (IGF-I) by cultured whole ovarian follicles and on P₄ and IGF-I output by cultured granulosa cells isolated from porcine ovaries. It was observed that in ovarian follicles cultured with nutrients/serum addition of IGF-I reduced release of P₄, but not of T or E₂. Exogenous leptin reduced output of E₂, but not of P₄ or T, and increased IGF-I output. No significant effect of FSH on release of steroid hormones by isolated follicles was found. Serum deprivation did not affect release of P₄, but reduced output of T and E₂, and promoted IGF-I release by cultured ovarian follicles. Addition of hormones failed to prevent the effect of malnutrition on the secretory activity of cultured ovarian follicles. In cultured granulose cells, all the tested hormones promoted release of both P₄ and IGF-I. Food restriction/serum deprivation reduced both P₄ and IGF-I output. Additions of either IGF-I, leptin and FSH prevented the inhibitory action of malnutrition on both P₄ and IGF-I release. The present observations (1) confirm the involvement of the hormones IGF-I, leptin and FSH in the control of secretory activity of ovarian cells, (2) demonstrate, that both isolated ovarian granulosa cells and whole follicles cultured in the absence of serum nutrients could be an adequate in-vitro model for studying the effect of malnutrition on ovarian secretory functions, and (3) suggest, that malnutrition could affect ovarian functions through changes in the release of ovarian hormones.

Psocid (Psocoptera) taxocoenoses were studied in forest ecosystems of the Western Carpathian Mts. in 1997-2001. As a study frame, vegetation tiers (VT = altitudinal vegetation zones) of geobiocoenological or forest-typological system were used. Lower units of forest typological system (forest type complexes) were used for the classification of ecological conditions and the material found in forest ecosystems of Abieti-fageta s. lat. communities (5^th fir-beech VT) was evaluated in detail. This VT is the most widespread in the regions under study (the Moravskoslezské Beskydy Mts., the Vsetínské vrchy Hills and Javorníky). 2,023 adults comprising 28 species were found in the 5^th VT. Caecilius burmeisteri was found as eudominant species; Philotarsus picicornis, Caecilius flavidus and Peripsocus subfasciatus were found as dominant species. In natural geobiocoenoses with the level of naturalness 1 or 2, the following species were found: Mesopsocus unipunctatus, Caecilius flavidus, and Caecilius burmeisteri as eudominant and Caecilius despaxi as dominant. Taxocoenoses of psocids were evaluated by Detrended Correspondence Analysis (DCA) and Divisive Cluster Analysis (DvClA). The axes were interpreted in DCA-analysis as follows: the x-axis denotes the influence of VTs and the q-axis refers to the influence of hydricity. This material was compared with other material obtained from various vegetation tiers in the Western Carpathians Mts. The characteristic species composition of psocids in the 5^th VT was as follows: Caecilius flavidus - C. burmeisteri - C. despaxi - Metylophorus nebulosus - Philotarsus picicornis.

The aim of the study is to evaluate the role of the Grand fir (Abies grandis [Dougl. ex D. Don] Lindl.) as a soil-improving species in the area of the University Training Forest in Kostelec nad Černými lesy, Jevany district. The state of humus forms in the stand part with Grand fir was compared with the mature Norway spruce (Picea abies [L.] Karst.) without regeneration, with young beech (Fagus sylvatica L.), Norway spruce (Picea abies [L.] Karst.) and oak (Quercus spp. L.) stands (all of pole stage). The site is characterized as 4P1 - acid oak-fir site with Luzula pilosa, the geological bedrock is formed of cretaceous sandstone with loess overlays, the soils are Luvisols, the terrain is flat at the altitude of 420-440 m a.s.l. The humus form samples (L, F, H, Ah horizons) were taken in 4 replications, quantitatively for the holorganic layers. The dry mass amount and total nutrient contents were analyzed for holorganic horizons, the basic pedochemical characteristics (pH, soil adsorption complex characteristics, exchangeable acidity and exchangeable nutrients) were determined for all horizons. The results confirmed marked and positive effects of the Grand fir litter on the surface layer characteristics. This tree species supports the litter of good composition, transforming easily and forming humus forms of higher quality compared to coniferous as well as studied broadleaved species.

There exists no energy policy in the European Union, but rather a whole series of long-term goals setting its strategic orientation. Until 2000, when the Green Book named "Towards the European Strategy of Energy Supplies Securing" was accepted, no real debate on the strategy of energy was held in the EU. The Green Book represents a key document of the European energy policy and it originated as a consequence of the fears of the European Committee regarding the growing energy dependence on the energy resources imports, from the politically not stable parts of the world. Among the three key points of the energy strategy, there belong stable supply of energy, acceptable energy prices and environment protection. With regard to the deepening European integration and interconnection of the individual member states economies, the decisions of one country also have an energy impact on the other states. Therefore, the cooperation among the individual members is necessary.

Colour and texture are very important quality properties of all foods. In this work, the influence was investigated of different types of pectin on colour and textural properties in strawberry jams and low-calorie strawberry jams containing fructose and aspartame or fructose syrup and aspartame. The highest anthocyanin content and total phenol content were detected in strawberry jam samples prepared with low methoxy amidated pectin. During storage, after 4 and 6 weeks at both storage temperatures, room temperature and 4°C, anthocyanin content and total phenol content decreased. Also, free radical scavenging activity decreased during storage. As far as the texture parameters are concerned, namely firmness, consistency and cohesiveness, the highest values were found in strawberry jam samples prepared with high methoxyl pectin.

The work was aimed at the growth suppression of cultured listerias strains by cultured lactococci strains or commercial mesophilic cheese cultures during common cultivations in the model UHT milk system (0.5% w/w of milk fat content) at 30°C during 18 h aerobically. Milk was primarily fermented by lactococci at the level of 10⁸ CFU/ml and secondarily contaminated by listerias at the level of 10³ CFU/ml. The most intensive growth suppressions of both Listeria innocua (CCM 5884 or Ln-03) strains were caused by Lactococcus lactis subsp. lactis (LCC 416 or CHCC 2281) strains or DELVO-ADD® 100-X DSF cheese culture; the listerias growth reductions was from the level of 10³ CFU/ml to 10⁰ CFU/ml. Obtained results should be applied to dairy industry provided that HACCP, GHP and GMP systems must be observed.

This paper presents the results of a three-year research on the effect of perforated polyethylene foil and polypropylene fibre covers on the growth of early potato cultivars at various lengths of plant covering period (2 and 3 weeks after plant emergence). Plants grown under covers were higher, produced higher mass of above-ground parts, and were characterised by a smaller value of leaf weight ratio (LWR) and leaf area ratio (LAR) compared with the cultivation without covering. In the case of plant covering for 2 weeks after emergence the mass of leaves at the time of cover removal was on average almost 2 times higher and the mass of stems over 2.5 times higher than in the cultivation without covering; the values of LWR and LAR were however smaller by 0.094 and 0.137 m

The water regime variability in most catchments is frequently influenced not only by the changes of the vegetation cover in the annual cycle but also by its development in the time span of decades. That means that the resulting evapotranspiration depends not only on the actual climatic situation but also on the soil moisture. The simulations of the rainfall-runoff process have been used with the intention to follow the possible role of the developing land cover. The differences between the observed and simulated flows in relatively long periods can be considered as an appropriate tool for the assessment of the water regime changes, in which the evapotranspiration demand variability is a significant phenomenon.

: The study evaluates production parameters (height, diameter at breast height, volume) of Douglas fir (Pseudotsuga menziesii [Mirb.] Franco) at mesotrophic sites of the Křtiny Training Forest Enterprise in mature stands. In total, 29 mixed stands were assessed with the registered proportion of Douglas fir at an age of 85 to 136 years. Comparing the 10 largest Douglas firs with the 10 largest spruces or larches higher, and as a rule markedly higher, production potential of introduced Douglas fir was found in all assessed stands. There were also groups of trees where the volume of Douglas fir was twice to 3 times higher than the volume of spruce or larch (see Tabs. 5 to 10). For example, in stand 177B11, the mean volume of 9.12 m³ was recorded in the 10 largest Douglas fir trees but the volume of spruce reached only 3.17 m³ and the volume of larch was 3.70 m³. Differences in mensurational parameters of Douglas fir found on the one hand and of Norway spruce (Picea abies [L.] Karst.) or European larch (Larix decidua Mill.) on the other hand compared by ANOVA tests were statistically highly significant. Annual ring analyses have shown that at present the volume increment of particular Douglas fir trees ranges from 0.12 to 0.16 m³ per year in mature stands (i.e. about 1.5 m³ every 10 years).

The mycological conditions on study plots established in forests growing on former agricultural farm lands were studied. In young spruce stand (8-10 years) reduced and unstable spectrum of macromycetes was found. After approximately 50 years of forest growth the situation became stable and spectrum of macromycetes together with development of mycorrhizal status were similar to a situation found in stands on forest soils. Slightly increased occurrence of saproparasitic species of fungi (e.g. Heterobasidion annosum at others) was observed in older growths.

The southern area of the province of Alicante (Spain) embraces the regions Vega Baja del Segura (The Low Valley of The Segura River) and Bajo Vinalopó (Low Vinalopó) in the Valencian Community. Although both regions have a growing residential, touristy and industrial potential, agriculture is still an important activity here. In this study, a characterization of agricultural land distribution in the southern regions of Alicante is carried out, regarding the main crops where the most important current problems are irrigation water shortage and low harvest prices. Incomes received by farmers according to the level of harvest prices and the evolution of these prices in the last two years are studied. Besides, prices have been noticed to keep stable at the best. The evolution of land for different uses, mainly industrial, is also estimated. The competition for land and water use with other sectors has significantly increased the amount of land for these uses and what is more, it is still on increase.

The heavy metal contents and their bioavailability were monitored in soils of Central Spiš region of SR. This area belongs to long term contaminated and hygienically loaded areas. Soil contamination by heavy metals is caused especially by ore mining, processing and treatment. Soil samples from the Central Spiš contained higher proportions of mobile forms which corresponded to the following sequence Pb > Zn > Cu, while for mobilizable forms the sequence of investigated metals was as follows: Cu > Zn > Pb. Soil pH is one of the parameters that affect significantly the share of bioavailable forms of metals. Higher proportions of mobile fractions of metals were detected in samples taken from soils with acidic pH. Statistical processing confirmed a relationship between the percentage share of lead and zinc in the mobile form and the level of pH/KCl, which was significant for Zn: r = -0.53. The relationships for lead and copper were insignificant.

The objective of the study was to examine a possibility of predicting phosphorus leaching from the top layer of agricultural soils by rainfall simulations by means of three multi-nutrient soil tests: Mehlich 3, NH₄-acetate extraction and water extraction (1:5, w/v). Another objective was to determine parameters of maximum phosphorus losses after an extreme load of rainfall on the top layer. Forty soils from different localities of the Czech Republic were used for the experiment. A leaching experiment was conducted in pedological cylinders with a soil layer of about 1 cm and with the bottom from a glass microfibre filter with pores 1.2 μm in size. Within 15 days the soils were flooded ten times with 25 mm of simulated rainfall in a minimum interval of 1 day. The closest regression between the soil test and phosphorus leaching was computed for NH₄-acetate soil test (R² = 0.8831) and Mehlich 3 test (R² = 0.8572) after the first application of 25 mm of rainfall. In water extraction it was for the mean of 10 simulated rainfalls (R² = 0.8674). As leaching proceeded, the closeness of regression diminished due to fluctuations of P concentration in leachates (increases and decreases), mainly in soils with higher P-test. The increase in P concentration could be caused by the activation of phosphorus from Fe-phosphates under anaerobic conditions in wet soils. The steepest decrease in P concentration in leachates was observed in light soils with low CEC value and higher initial P-test.

Lettuce (Lactuca sativa) is the most important crop in the group of leafy vegetables. It is characterized by considerable morphological and genetic variation. The crop comprises seven main groups of cultivars (including oilseed lettuce) differing phenotypically; they are usually described as morphotypes. Lettuce breeding is primarilly focused on various morphological features and resistance against diseases and pests. The accurate description of lettuce germplasm provides basic information useful for lettuce breeders. The construction of a lettuce descriptor list has been stimulated by the international genebank community. This list consists of 55 descriptors with 15 elucidated by figures. It provides a tool for detailed characterization of and discrimination within the intraspecific variation of L. sativa, verification of old varieties, and identification of putative duplicates and gaps in germplasm collections. These descriptors, along with descriptors of wild Lactuca species, provide an efficient analytical tool for studying the complex morphological variability of this genus and relationships among the species.

Koch method of ornamental trees evaluation is based on interest paid on costs invested in tree-growing up to their maturity stage minus deductions for age, defects and damage. The aim of this paper is to apply the above mentioned method in the economic conditions of the Czech Republic. The paper presents essential economic data generated in accordance with the technological model of tree growing at a permanent site. We also describe the mechanism of the so-called base tree price calculation as a basis for the subtraction of deductions derived from its current condition. The calculated base tree prices are illustratively compared to prices based on the to-date applied calculating techniques and the relevant regulation. We also refer to the method of base price adjustment based on the criterion of landscape tree value. The mechanism of price calculation applied for Koch method testing included two modifications. The first relates to due consideration of growth qualities when calculating development care costs; the other introduces landscaping value indicator as the only base price adjustment to achieve the resulting price, corresponding with the current tree condition.

The afforestation of agricultural lands was carried out under different site and ecological conditions, including lower and medium elevated localities. The present study documents the rapidity of accumulation of surface layers and their characteristics in stands of Scots pine (Pinus sylvestris), Norway spruce (Picea abies), birch (Betula verrucosa) and Douglas fir (Pseudotsuga menziesii) in the territory of the Training Forest Enterprise in Kostelec nad Černými lesy, at the altitude 430 m a.s.l., on the site of nutrient-poor gleyed soils. The plots were compared with the neighbouring continuously forested site covered with old pine-spruce stand and with near-situated arable field. During the first roughly 40 years, considerable changes were documented on the afforested plots. Forest-floor humus layers in the coniferous stands have already been formed, the humus forms being more favourable compared with the old forest site. Acidification and loss of nutrients run in the upper mineral horizons. These processes were also responsible for the less favourable character of the forest soil in the old stand. Birch showed minor shifts of soil properties in the mineral horizon compared to the conifers; the surface humus accumulation was not observed there yet. The lowest degradation among conifers was shown in Douglas fir, intensively taking up deficient nutrients on the other hand.

The article describes the competitiveness of Slovak agricultural and food products after the accession of the Slovak Republic into the EU. The analysis has shown that even despite the increased subsidization and full liberalisation of trade, the competitiveness of our products still needs to develop. The main reason behind this is the poor efficiency of production and the lack of innovation activities. Most agricultural commodities are profitable only because of subsidies. Processing industry is the main contributor to the worsening deficit of trade balance. Specific commodities with good sales potential in the EU market include cereals, malt, wheat flour, dairy products, live cattle and sheep meat.

Tyramine is the most frequent biogenic amine found in cheese and is also frequently found in other fermented foods and beverages. In total 273 different strains of enterococci from various foodstuffs were studied. A multiplex PCR was designed for the genotypic differentiation of various enterococci strains at species level and for determination of the presence of tyramine producing (tyrdc) gene. E. faecalis and E. faecium were found to be prominent strains in dairy and meat products while, E. faecium and E. mundtii were found to be ruling in case of fruits and vegetables. HPLC analysis was carried out for determination of levels of tyramine. 211 i.e. 86.8% of samples were containing about 1000-1500 mg/l of tyramine, while 10 i.e. 4.1% were found to have tyramine in the range 100-500 mg/l. Negative samples showed 0 mg/l of tyramine.

There is little experimental evidence about the functional significance of arbuscular mycorrhizal fungi (AMF) colonization in providing nutrients for lowland rice. This study was undertaken to examine whether growth and nutrient deficiencies may affect plants benefit from AMF inoculation. Two contrasting rice (Oryza sativa L.) genotypes and two AMF species (Glomus mosseae and G. intraradices) were used in this experiment. Under P starvation, P uptake in the genotype tolerant to P deficiency (Fajr), declined significantly up to 36% (P < 0.05) in response to AMF inoculation, while it enhanced by about 70% (P < 0.01) in susceptible genotype (Shafagh). Under Zn starvation, Zn uptake of Zn-efficient genotype (Shafagh) increased by about 2 fold (P < 0.01), but a reduction of 52% (P < 0.05) was observed in the Zn-inefficient genotype (Fajr) upon mycorrhization. Greater genotypic differences were observed for -P-Zn plants. Our results imply that genotypic difference in responsiveness to inoculation with AMF is attributable to different contribution of mechanisms for increased nutrient uptake in mycorrhizal plants depending on nutrient, nutritional status and nutrient efficiency of genotypes.

Soil micromorphology was applied to specify flow domains in different soils and to select a suitable numerical model for simulation of water flow and herbicide transport. Pore structure detected on soil micromorphological images represented in all cases domains of prevailing water flow and solute transport. Depending on pore configuration and boundary conditions either water immobilization or preferential flow was observed and simulated. The benefits and limitations of the soil micromorphology imaging are discussed and compared with the more often used X-ray computer tomography, magnetic resonance imaging and dye tracer imaging.

In the years 2005, 2006, and 2007 the described pomological characteristics were evaluated and both heritability and correlation coefficients of the determined characteristics of parents and progeny were estimated for the Minaret × Betinka apricot hybrid population. Estimated heritability of fruit weight, over colour and flesh consistency was approximately 0.9. Heritability of flesh colour, fruit attractiveness and fruit flavour ranged from 0.6 to 0.9. The correlations show a strong dependence of the following characteristics of parent varieties and progeny: over colour and fruit attractiveness. Medium strong dependence was determined in the following characteristics: fruit colour and fruit flavour. Weak dependence was found in the case of fruit size.

The spruce-fir-beech dominated forest stands in Litschau in the Austrian part of the Bohemian Massif were converted by former forest management practices into pure Norway spruce stands and are now discussed to be reconverted into the potential natural vegetation type. The targeted potential natural vegetation type is usually defined by experts in vegetation sciences. Because meanwhile individual-tree growth simulators are a well acknowledged tool for predicting future forest stand development, in this study we investigate if PROGNAUS can also be used to predict the redevelopment of managed forest ecosystems into natural forest ecosystems regarding species composition. The development of 23 stands in Litschau has been simulated over 1,000 years under the "no-management" option. Generally, the simulated species distribution agrees quite well with the expectations of the potential natural vegetation type. However, the predicted amounts of silver fir and maple species are lower than expected, which probably is due to browsing and management effects represented in the parameterization data for PROGNAUS.