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In the contribution, there is discussed the usage of the method based on the grammatical and differential evolution for the automatic discovery of regression models for discrete datasets. The combination of these two methods enables the process to find the precise structure of the mathematical model and values for the model constants separately. The used method is described and tested on the selected regression examples. The results are reported and the obtained mathematical models are presented. The advantages of the selected approach are described and compared to the classical methods.

Eight individual bacteriocin-producing lactic acid bacteria (LAB) strains and three bacteriocin-non-producing cheese starter cultures were evaluated for their ability to inhibit the growth of six Listeria monocytogenes strains, originating from the guinea-pig lymph nodes, raw cow milk, and manufacturing dairy equipment. Results showed that either live cells or cell-free neutralised supernatant (CFNS) and/or heated CFNS of six individual LAB strains (Lcc. lactis subsp. lactis CCDM 416 and NIZO R5, Lbc. plantarum HV 11 and DC 1246, P. acidilactici HV 12, and Ent. mundtii CCM 1282) and one starter culture (DELVO-ADD^® 100-X DSF) were effective in the suppression of at least one listeria strain. Neither any individual LAB strain nor starter culture was antagonistic toward all studied L. monocytogenes strains, indicating diverse sensitivity/resistance among L. monocytogenes strains to antimicrobial compounds of LAB. The significant susceptibility of listerias isolated from raw milk and dairy equipment together with the strong antilisterial activity of DELVO-ADD^® 100-X DSF could be applied in dairy technology, where commonly used starter cultures could play both the biopreservative and fermentation role.

We characterised 12 wines (10 red, 1 sweet red, and 1 white) from different Cypriot cultivars in terms of their phenolic, anthocyanin composition, and antioxidant capacity as determined by two activities: radical scavenging and ferric reducing ability. Two different phenolic fractions (tannin-free and 1-kDa permeate) were also isolated from Cypriot wines with an ultimate goal of investigating their role in the overall antioxidant capacity of wines. The results indicated that Maratheftiko and Lefkada cultivars had higher concentrations of o-diphenols, hydroxycinnamic acid derivatives, flavonols and anthocyanins compared to other Cypriot cultivars like Ofthalmo, Mavro, and Giannoudi. The higher concentrations of phenols did not always correspond to a higher antioxidant capacity, probably due to the antagonistic action observed between hydroxycinnamic acid derivatives, flavonols, and anthocyanins. The latest interactions restricted the release of flavonols' advanced antiradical activity in wines.

Antioxidant activities and free radical-mediated DNA strand breakages of five hydroxycinnamic acids were examined. Kinetic analysis of a stable galvinoxy (GO*)-scavenging reaction of hydroxycinnamic acids demonstrated that the molecular structure and the reaction medium were two important factors affecting the antioxidant mechanism and activity. In methanol, the kinetic process of the compounds, which have electron-donating groups (-OH, -OCH₃) in the ortho- or para-position of 4-OH, was primarily governed by the sequential proton loss electron transfer (SPLET mechanism). While, in ethyl acetate, the reaction mechanism is predominantly direct hydrogen atom transfer (HAT mechanism). But for the compounds having only one hydroxyl, both in ethyl acetate and methanol, the reaction mechanism is only HAT. At the same time, the compound bearing o-diphenoxyl is not the most active one in our tested environment.

Whole grain cereals such as oats are important sources of phenolic compounds. Oats contain phenolic amides, also named avenanthramides (AVAs), which have beneficial health properties because of their antioxidant, anti-inflammatory, and antiproliferative effects. The most common avenanthramides are esters of 5-hydroxyanthranilic acid with p-coumaric (AVA-A), ferulic (AVA-B), or caffeic (AVA-C) acids. The studies related to the stability of AVAs showed that AVA-B is sensitive to alkaline and neutral conditions and this sensitivity increases with higher temperatures. However, has been reported that AVA-A and AVA -C are more stable under the same conditions (alkaline and neutral conditions), and in addition that AVAs content of oats is increasing significantly with the germination process. AVAs help in preventing free radicals from damaging LDL cholesterol while AVAs-enriched extract of oats combined with vitamin C synergistically inhibited LDL oxidation in vitro. Both animal studies and human clinical trials confirmed that oats antioxidants have the potential of reducing cardiovascular risks by lowering serum cholesterol and inhibiting LDL oxidation and peroxidation. Therefore, the consumption of oats and products thereof is extremely important in reducing the risk of cardiovascular diseases.

The mitotic chromosomes of Lablab purpureus (L.) Sweet were characterised using sequential combined propidium iodide (PI) and 4',6-diamidino-2-phenylindole (DAPI) (CPD) staining and fluorescence in situ hybridisation (FISH) with 5S and 45S rDNA probes. The detailed karyotype of this species was established using prometaphase chromosomes. After CPD staining, CPD and DAPI⁺ bands were shown simultaneously. CPD bands occurred in the proximal regions of the long arms of all chromosome pairs and at all 45S rDNA sites, while the DAPI⁺ bands appeared in all centromeres. FISH with rDNA probes revealed one 5S locus and eight 45S loci. The single 5S locus was interstitially located on the long arms of the shortest chromosome pair. Among the 45S loci, two large loci were located in the secondary constrictions of the short arms of two chromosome pairs; six small or minimal loci were proximally located on the short or long arms of six chromosome pairs. Each prometaphase chromosome pair could be identified using the CPD and DAPI⁺ bands, the rDNA-FISH signals in combination with the chromosome measurements and condensation patterns. The karyotype was formulated as 2n = 2x = 22 = 14m (2SAT) + 6sm + 2st (2SAT), and the asymmetry indices, CI, A1, A2, As K%, AI and the Stebbins category were 38.23 ± 7.06, 0.36, 0.31, 61.99, 5.68 and 2B, respectively.

: In chick hatcheries, males of laying hybrids are considered to be "waste" and the majority of these males are killed just after hatching. On the other hand, the interest of consumers in products from alternative systems (organic, free-range) is increasing. The idea was to evaluate the meat quality of these males when they have access to free range because there is not such a study available. The aim of this study was to compare the physical and sensory quality of the meat of layer males with fast-growing broilers at the same age when they had both access to free range and when they were fed to 49 and 90 days of age. Slow-growing ISABROWN (IB) layer males and fast-growing Ross 308 (RS) chickens were kept in free-range conditions to evaluate carcass and meat quality at 49 days and 90 days of age. Live weight, carcass yield, breast meat yield and the proportion of abdominal fat were significantly higher (P < 0.001) in RS at both ages. The proportions of fat in the breast meat were significantly lower (P < 0.01) in IB at both ages. The value of pH 24 h was significantly higher in IB and the meat was darker (P < 0.001) in these chickens. The overall acceptability was significantly better (P < 0.01) in IB at 90 days of age. The laying males are acceptable for an alternative system of poultry meat production from the aspect of meat quality. The quality was comparable or even higher in comparison with fast-growing chickens.

The objective of this study was to evaluate the effects of the different ratios of acetate and β-hydroxybutyrate (BHBA) on cell viability, triacylglycerol (TAG) content, and mRNA expression of the genes related to lipid and protein synthesis in bovine mammary epithelial cells (BMECs). Primary cells were isolated from the mammary glands of Holstein dairy cows and were passaged twice. Then, the cells were cultured with different ratios of acetate and BHBA (1 : 3, 1 : 2, 1 : 1, 2 : 1, 3 : 1, 4 : 1, and 1 : 1, Group 1 to Group 7, respectively) for 48 h, and the fetal bovine serum in the culture media was replaced with fatty acid-free bovine serum albumin (BSA) (1 g/l). The control culture media contained only fatty acid-free BSA without unsaturated fatty acids (0mM). Cell viability was not affected by adding different ratios of acetate and BHBA, but TAG accumulation was significantly influenced by supplementing the culture media with different ratios of acetate and BHBA. The expression levels of genes related to milk fat (FASN, ACACA, CD36, SCD, FABP3, LPL, PPARG, and SPEBF1) and milk protein-related genes (CSN1S1, CSN3, mTOR, 4E-BP1, S6KB1, STAT5, JAK2, and LEPTIN) were significantly affected by the addition of different ratios of acetate and BHBA to the BMECs. Our results suggested that Groups 3 and 4 (1 : 1 and 2 : 1) had a stronger acceleration of milk fat synthesis, and Group 4 (2 : 1) had the strongest effect. The expression of the CSN1S1 and LEPTIN mRNAs was more effectively promoted in Groups 3 and 4 (1 : 1 and 2 : 1), and Group 3 (1 : 1) had the strongest acceleration. Expressions of genes related to milk protein synthesis (mTOR, 4E-BP1, S6KB1, JAK2, and STAT5) were up-regulated using a ratio of acetate and BHBA of 2 : 1. Taken together, the 2 : 1 ratio of acetate and BHBA had the best effect for both the milk fat synthesis and milk protein synthesis genes. However, further studies are necessary to elucidate the mechanism for regulating milk fat and protein synthesis by different ratios of acetate and BHBA.

Black raspberry necrosis virus (BRNV) is one of the most important viral pathogens of Rubus spp. In this study, a procedure combining in vitro culture and heat therapy on axillary buds of Rubusoccidentalis was developed to eliminate BRNV from infected plants. Axillary buds were grown aseptically at 4-h alternating periods of 29°C and 38°C with 14-h day length for 1-5 weeks. Shoots induced after thermotherapy were tested for the viruses by RT-PCR. BRNV was not detected in any shoots indicating that BRNV was heat labile. BRNV-free shoots were rooted in vitro and acclimatized in greenhouse. Regenerated plants remained virus-free after 2-month acclimatization, 3-month dormancy and 5-month growth periods.

The effects of two strength media (full and half) in inorganics and five polyvinylpyrrolidone (PVP) concentrations combined with 1 mg/l indole-3-butyric acid on the in vitro rooting of the CAB-6P, Gisela 6 and M × M 14 cherry rootstocks were investigated. For the CAB-6P, root number (5.80) was greatest by adding 5 g/l PVP to the half strength medium and 1 g/l PVP resulted in 80% rooting percentage. For Gisela 6, 1 g/l PVP in half strength medium led to the highest root number (6.30) as well as the highest rooting percentage (90.91%). On the contrary, root length was maximum (36.17 mm) in the full strength medium without adding PVP. In M × M 14, root number was maximum (8.33) in the PVP-free full strength medium, rooting percentage was 100% by adding 5 g/l PVP to either full or half strength medium and root length was greatest by incorporating 1 or 2.5 g/l PVP into the half strength medium. PVP seems to be a promising rooting agent in tissue culture systems.

The paper presents an attempt to determine conducting area (CA), relative conducting area (CA.k^-1) and mean ring conducting area (CAar) on discs cut at breast height from stems of larch trees growing in fresh mixed coniferous forest and fresh mixed forest sites, representing four age classes and the main crop according to Kraft's classification. The value of CA increases with an improvement of the social class of tree position in the community, while no such dependences were found for the value of (CA.k^-1). The parameter CAar, except for one case in age class IV in the fresh mixed coniferous forest site, increases with an improvement of the position a tree takes in the community and differentiates more markedly under the conditions of fresh mixed forest sites. Relative conducting area (CA.k^-1) decreases markedly with an increase in the age of trees, which is confirmed by high values of the coefficient of determination. Moreover, the significance of differences between individual trees in the main crop according to Kraft and forest site types was tested in terms of the values of CAar. Calculated values may be used to describe the relationships between conducting area and the size of the assimilating organ more precisely than the total sapwood zone.

Adapting forests to climate change involves silvicultural measures such as use of a range of species and the fostering of mixed stands. We tested these in a Sitka spruce forest in southern Scotland, employing the Ecological Site Classification to match suitability of 24 species to six climatic and edaphic variables under values of accumulated temperature and moisture deficit projected for a medium emissions scenario for the present century. Both median and 90^th percentile values were contrasted. In the first case there was a small change in species suitability with Sitka spruce, noble fir, downy birch, sycamore and aspen being the most suitable species. When the 90^th percentile values were employed, the suitability of Sitka spruce and similar conifers had declined by the 2050's due to soil moisture deficits. The actual performance of a range of species in a long-term experiment on a similar, warmer site showed several productive conifers including Sitka spruce that maintained reasonable growth when planted in mixture. Mixed plots were developing into pure stands of the most productive species. Species diversification was the most practical adaptation measure for this forest and should concentrate on areas of the greatest risk like south-facing slopes with free-draining soils.

Forest fires under conditions of the Czech Republic are evaluated from the aspect of their frequency of occurrence in 1992-2004 at a level of particular years, seasons, days and daytime, and causes of their origin. They are confronted with a situation in the CR in 1974-1983. Effects of climatic conditions are a limiting factor not only for the frequency of their origin but also for the size of the burnt area. Spring (April) and summer (August) culminations were balanced. The burnt area of the best part of forest fires (88.9%) was < 1 ha. The increased frequency of forest fires was noted in afternoon hours and during weekends. Areas threatened by fires are characterized by the increased visit number. In the spectrum of causes, a dominant position is taken up by fire raising, smoking and management in the forest. Railway operation and lightning represent minority causes of the origin of forest fires. In the course of the year, the structure of forest fire origin changes depending on activities in the forest and visit number.

A few individuals of Grayish oak have been observed in the Low Murgia Plateau, Puglia Region. This is the first time that Quercus pedunculiflora C. Koch has been found in Italy. The territory is dominated by olive trees, where spontaneous vegetation occurs only in residual patches in particular along an important old dry erosion stream, Lama Lamasinata. Individuals of Grayish oak are located along a rural road and in a closed abandoned park which is in the vicinity of Lama Lamasinata, near Balsignano, one of the most important archaeological sites of the Low Murgia Plateau. In the area other deciduous oaks such as Italian pubescent oak, the most common spontaneous oak in the western district of the Murgia Plateau, and Hungarian oak, which is very rare in the Low Murgia Plateau, have been observed.

Wild boar is a native species in the fauna of the Czech Republic. It is becoming a problematic game species both in the Czech Republic and in other European countries due to its harmful impacts. So far no suitable method of its sustainable management has been devised. Yet, a correct abundance estimate is essential for proper management, field crop damage prevention and proper hunting planning. This paper employed faecal pellet group count to estimate the wild boar density in a forest environment. The research was conducted in a study area covering 12.83 km², which is surrounded by farmland. The count was done under ideal conditions in early spring, after snow had melted. The study area was organised into several differing environments in which different dung densities were expected. The presence of feeding sites, where wild boars concentrated, was taken into account. The conducted count confirmed differences in the utilization of different habitats within the study area. The resulting wild boar abundance was estimated at 64.3 (± 8.9; 95% CI) indd.km^-2.

Sawflies were collected in the northeast of the Czech Republic using Townes type Malaise traps. Traps were placed in eleven young Norway spruce (Picea abies) forests during the period from 1998 to 1999. Localities cover altitudes from 230 to 1,000 m a.s.l. In total, 285 species of Symphyta have been recently known from the study area (Xyelidae - 1, Pamphiliidae - 7, Argidae - 10, Cimbicidae - 3, Diprionidae - 5, Tenthredinidae - 252, Siricidae - 1, Xiphydriidae - 1, Cephidae - 5). The majority of the species have large distributional ranges and their host plants are forest tree species. Most of the sawflies were obtained from Malaise traps located in the young spruce stands, and therefore the silvicolous species prevail. Neodineura arquata represents a new genus and species and Heptamelus dahlbomi a new species for the fauna of the Czech Republic. Nine species have been classified as endangered and twenty-one species have been classified as vulnerable. Pristiphora robusta has been deleted from the list.

Afforestation of agricultural lands may be a positive action in many cases. Especially, it is a beneficial feature for waterlogged soils, stony soils or for soils which are less fertile for any other reason and thus unsuitable for farming. Afforestation can be a very important action even in the agricultural landscape - afforested belts of agricultural land divide large farm blocks into smaller ones, or act as windbreakers and biological corridors. The value, quality and fertility of soil can be assessed in different ways. The study aims to determine the identification soil criteria of agricultural land which is suitable for afforestation. This evaluation process is based on Evaluated Soil Ecological Units (ESEU), in the Czech Republic known as BPEJ, database which is available for all agricultural land in the Czech Republic. The results are represented by a complete list of ESEU codes suitable for afforestation. The list of codes is supplemented by an explanation why such an ESEU code, representing a soil group with similar properties, is suitable to afforestation.

Afforestation of agricultural lands may be in many cases a positive step. Especially, it is a beneficial with waterlogged soils, stony soils or for soils which are for any other reason less fertile and unsuitable for farming. Even too in the agricultural landscape, afforestation can be very important by the breaking of large farm blocks by windbreakers and bio-corridors. The value, quality and fertility of soil can be assessed in different ways. The aim of this study is to determine the criteria for the identification of agricultural land suitable for afforestation. This evaluation process is based on Evaluated Soil Ecological Units (BPEJ) that are publicly available and already processed for all agricultural land. The results are represented by complete list of Evaluated Soil Ecological Units that are suitable for afforestation with stating the reason why they were chosen.

Two forested catchments in the Bohemian Forest (Šumava Mts.) were investigated according to the species composition of herb layer and aboveground plant biomass. The bark-beetle gradation was observed in the Plešné Lake catchment during this study. The community dynamics depends mainly on the altitudinal zone of the site. Variability in the species composition was more pronounced in the sites of natural broadleaved mixed forests than in the sites of natural Norway spruce forests. Three processes were recorded after the tree layer damage: tree regeneration (very rapid), appearance of some species typical of the clear-cuts (only limited, mainly after windthrows) and disappearance of some species (limited, probably for a short time only). The aboveground biomass was variable. Some relations to the canopy decline were observed for Vaccinium myrtillus. The stock changes depend on the population features of this species and can differ (increase or decrease) according to individual localities.

Poplars are fast-growing broadleaved tree species inhabiting river banks and sites with accessible water supplies. Vegetative propagation makes them suitable for establishing highly productive plantations along big rivers and in flooded plains. The production of large quantities of biomass provides a good substrate for various organisms. The aim of this study was to identify fungal species occurring in the poplar plantations in Serbia and to determine their frequency and role in decomposition of tree parts. Fifty species belonging to the divisions Ascomycota, Basidimycota and Deuteromycota as well as two species from Oomycota (the genus Phytophthora) were reported. Bark was the substrate for 27 species, 14 species were found on leaves and 9 species were wood-decaying fungi.

Clonal propagation is widely used for Acacia breeding and commercial planting. When a large number of clones are handled, problems with mixings are commonly confronted. Detection of admixture in Acacia clones based on morphology particularly at seedling stage is not feasible. However, molecular markers are commonly used to test the genetic fidelity of planting materials. This paper reports the detection of mislabelling in Acacia clonal progenies using a sequence tagged microsatellite (STMS) genetic marker system. Progenies from two mapping populations were clonally propagated and field planted for phenotypic and genotypic evaluation at three locations in Malaysia: (a) Forest Research Institute Malaysia field station at Segamat, Johor, (b) Borneo Tree Seeds and Seedlings Supplies Sdn, Bhd. (BTS) field trial site at Bintulu, Sarawak and (c) Asiaprima RCF field trial site at Lancang, Pahang. During field planting mislabelling was reported at Segamat, Johor and similar was suspected for Bintulu, Sarawak. Screening revealed mislabelling events in both populations. A total of 18.52% mislabelling incidences were detected from both sites, of which 17.39% of mislabelling was detected for fibre length cross and 20% for wood density cross. The assignment test efficiently reestablished the mislabelled ramets to the respective clones. Future studies should be focused on the utilization of a higher number of markers, e.g. SSR or SNPs to increase a discrimination power. A high number of SNPs can be generated within a short period of time compared to SSR, but SNPs could be cost inhibitory. Multiplexing microsatellite combinations along with sample bulking will further reduce the processing time when screening large populations. The use of assignment test would efficiently assign mislabelled individuals to the respective clones. It is concluded that checking for mislabelling is imperative for future breeding and for analyses such as QTL mapping where a correlation between genotypic and phenotypic data is determined.

The aim of this study was to determine the effect of agricultural land afforestation on soil characteristics. Two sites in two regions of the Czech Republic were evaluated, at lower as well as higher submountain elevations: in the regions of the Orlické hory Mts. and Kostelec nad Černými lesy, afforested, arable and pasture lands were compared for basic chemical and physical characteristics. It was determined: pH, CEC, exchangeable nutrients, SOC, bulk density, volume density, porosity (differentiated by pore size), water conductivity and soil aggregate stability. This study demonstrated the important influence of previous land use upon soil characteristics. The characteristics of the arable horizon can persist for many years; in forests, the mineral horizons (15-30 cm) can persist within 15-30 years after afforestation. Afforestation, which caused an increase in soil porosity by decreasing reduced bulk density and increasing capillary and gravitational pores (increasing the water-holding capacity and soil air capacity), is important for maintaining the soil stability. The positive effect on infiltration and retention capacity resulted not only from the presence of a forest overstorey, but also from the presence of permanent grass cover of pasture land.

Pitfall traps were used to capture 3,550 individuals and 34 species of Myriapoda in five pairs of Norway spruce and beech stands in the Moravskoslezské Beskydy Mts. (Czech Republic). Differences in the occurrence of Chilopoda, Diplopoda and Isopoda on sites with spruce and beech were determined by F-test. Diplopoda and Isopoda preferred beech stands and Chilopoda spruce stands. The species Protracheoniscus politus (Koch) (Isopoda) indicated a positive relation to beech stands. Among Diplopoda, a strong linkage to beech was seen in Glomeris hexasticha (Brandt), while Julus scandinavius (Latzel), Hassea flavescens (Latzel) and Brachyiulus bagnalli (Curtis) tended to prefer the spruce forest environment. The highest variability was found in Chilopoda, of which the species dominating in beech stands are Cryptops parisi (Brölemann), Strigamia acuminata (Leach) and Strigamia transsilvanica (Verhoeff), while Geophilus flavus (DeGeer) and Geophilus insculptus (Attems) prevail in spruce stands. A wide spectrum of captured species of the order Lithobiomorpha differentiate in their relation to spruce [Lithobius forficatus (L.), L. cyrtopus Latzel, L. erythrocephalus C.L. Koch, L. tenebrosus Meinert, L. austriacus (Verhoeff), L. biunguiculatus (Loksa)] and beech [Lithobius microps (Meinert), L. mutabilis L. Koch, L. burzenlandicus Verhoeff, L. micropodus (Matic) and L. nodulipes Latzel]. Based on the findings, we can confirm increased incidence in beech forests, although the result is not unambiguous. Therefore, it is necessary to admit that the factor of the main tree species within a stand cannot be used as the single criterion and needs to be supplemented with additional conditions of the natural environment.

The goal of this study was to analyse the quality and dormancy of beechnuts originating from different harvesting sites within large UA and to determine the homogeneity of seed lots from large-scale areas. Currently, European beech (Fagus sylvatica L.) accounts for 7.21% of the forested area of this country. Almost 24,000 ha of beech are registered as units of approval (UA) for harvesting of reproductive material. About 40% of these UA are made up of areas of 10 ha consisting of stands with different micro-sites. Beechnut dormancy and thus the chilling requirements for the rate of germination are affected by provenance and weather conditions (precipitation and temperature) during seed maturation. Beechnuts collected from different harvest sites reached significantly different germination and also showed different degrees of dormancy. Results illustrated that beechnut seed lots collected from large areas (a set of different stands) can show high heterogeneity in germination and dormancy and this can significantly affect the uniformity of pre-sowing treatment and emergence in nurseries.

In fixed count sampling (FCS) a fixed number (k) of observations is made at n randomly selected sample locations. For estimation of stem density, the distance from a random sample location to the k nearest trees was measured. It is known that practical FCS estimators of stem density are biased. With the objective of reducing bias in FCS estimators of stem density, a new estimator derived from a survival function with distance acting as time was presented. To allow for spatial heterogeneity in stem density, the survival function includes shared frailty. Encouraging results with k = 6 in terms of bias, root mean squared error (RMSE), and coverage of nominal 95% confidence intervals were obtained in an extensive testing with simulated random sampling from 54 actual and four simulated spatial point patterns of tree locations. Sample sizes were 9, 15, and 30, with 1200 replications per setting. The performance across sites of the new FCS estimator was variable but almost paralleled that of a design-based estimator with fixed area plots. Users of the new FCS estimator can expect an absolute relative bias and a root mean squared error that are 1% greater than for sampling with fixed area plots holding an average of k trees. The chance of a smaller RMSE with the proposed estimator was estimated at 0.44.

Effects of floral herbivory (grazing flowers) by slugs on production and quality of seeds of herbaceous plants have been rarely quantified. We studied consequences of grazing by an invasive slug Arion lusitanicus (Mabille) for inflorescences of dandelion (Taraxacum officinale Weber ex Wiggers). In May 2008, a grassy site in Prague-Ruzyně (Czech Republic) was densely populated by dandelion inflorescences. Of the 40% of the flowers grazed by the slug, 70% died before seed dispersal and seed was eaten from 10% of the closed mature inflorescences. Viability of seeds from inflorescences that survived slug grazing was not affected. In addition to seedling predation, grazing of flowers may be an important source of dandelion mortality at sites where this slug is abundant.

The effects of land use practices on soil fauna, especially earthworms, are poorly known in coastal saline agricultural soils. Here we compare earthworm communities in six types of land use practice in the coastal region of China's Bohai Bay, namely uncultivated saline soil, two orchard (pear and winter jujube) lands, man-made forests (chinese ash), vegetable land and cropped land (maize). In addition, we recorded selected physicochemical properties of the soil. Soil organic matter content and total N were significantly higher under pear orchard and vegetable land than under the other land use practices, and their lowest values were observed from uncultivated saline soil. Vegetable land and pear orchard land showed a significantly higher abundance of earthworms than the other land use practices, whereas no earthworm was found in uncultivated saline soil. The sites under individual practices supported one to three earthworm species. Aporrectodea trapezoides species was present under four types of land use practice, and the biomass of this species accounted for more than 60% of the community. Vegetable land and pear orchard land supported richer earthworm community than the other land use practices, dominated by Aporrectodea trapezoides and Drawida japonica. These preliminary results indicated that land use practices have substantial effects on the abundance and composition of earthworm communities in saline soils.

The aim of this work is to evaluate the changes of Mehlich 3 - P, K, Ca and Mg contents in soil during a long-term field experiments with sewage sludge, farmyard manure (FYM) and mineral NPK (NPK) application, compared to the control non-fertilized treatment. The experiment was established at the Humpolec and Suchdol sites (Czech Republic). Potatoes, wheat and barley were grown in crop rotation. Fertilizing system was based on the same nitrogen dose of 330 kg N/ha per one crop rotation. Archive soil samples from the beginning of the experiment (1996) and from the end of each year's crop rotation (1999, 2002, 2005, 2008 and 2011) were analyzed. In spite of the different soil-climatic conditions of the studied sites, very similar tendencies of P, K, Ca and Mg contents changes after the fertilizing systems used were observed in the soil. In case of the same nitrogen dose (330 kg N/ha), sewage sludge appeared to be better source of bioavailable soil phosphorus compared to the farmyard manure and NPK. On the contrary, FYM was a better source of bioavailable potassium and magnesium, despite the lower total magnesium content in FYM. The NPK treatment was the best long-term source of bioavailable potassium.

It is postulated that stabilized ammonium fertilizers improve fertilizer-N utilization by crops, leading thus to higher yields with the same fertilizer rate, especially on sandy soils. However, it must be taken into consideration that in clayey soil at least a part of the NH₄⁺ ions may be fixed by 2:1 clay minerals, thus delaying the effect of the N fertilizer. Because NH₄⁺ and K⁺ have similar size and valence properties and therefore compete for the same non-exchangeable sites of 2:1 clay minerals, we investigated the influence of time and K⁺ application rate on both fixation and release of NH₄⁺. Fixation of NH₄⁺ ions was higher when K⁺ was applied after NH₄⁺, while the influence of the K⁺ application rate was less pronounced. Mobilization of non-exchangeable NH₄⁺ was retarded when K⁺ was applied at the high rate after NH₄⁺. At the first harvest yield formation of ryegrass was neither influenced by the amount as well as the application time of K⁺, because plant available N was not growth limiting, while yield of the second harvest was significantly higher with the low K⁺ application rate after NH₄⁺. After the second harvest the blocking effect of K⁺ on the release of non-exchangeable NH₄⁺ was attenuated and the highest yields of the third cut were reached in the treatments with the high K⁺ application rate after NH₄⁺. Total dry matter yield was highest when K⁺ was applied at the low rate after NH₄⁺. Our results show that K⁺ governs fixation and release of non-exchangeable NH₄⁺, which should be taken into consideration when applying ammonium containing N fertilizers like ammonium sulfate, ammonium sulfate nitrate and ENTEC. Thus K⁺ can affect N availability when N is applied as NH₄⁺ in both the short and long term.

In the present study, three soils (Ferralsol, Luvisol topsoil, and Luvisol subsoil) were amended with biochars (charcoal, hydrothermal carbonization coal (HTC) of bark, and low-temperature conversion coal of sewage sludge), wheat straw and a control (no amendment) and incubated over a period of 365 days. Each amendment was applied at a rate of 11.29 g C/kg soil. After incubation, the soils were analyzed to retrieve three density fractions (free fraction (FF), intra-aggregate fraction (IAF), and heavy fraction) which were analyzed for total carbon (TC) contents and scanned by fourier transform infrared spectroscopy (FTIR). The biochars and straw significantly increased the TC contents of soils as compared to control. Among soil organic matter (SOM) density fractions, higher TC contents were documented in the FF and IAF from biochar treatments as compared to the straw. The FTIR spectra of the FF from the charcoal and HTC treatments showed the presence of aluminosilicate minerals on surfaces of SOM. There were slight changes in the FF of straw and HTC treatments as compared to spectra of original amendments. The study suggests that the stability of charcoal and HTC in soils is due to the recalcitrant nature of biochar followed by occlusion into soil micro-aggregates.