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The whole buckwheat flour (WBF) was used in Turkish flat bread, lavaş, up to 30% level without gluten, and up to 40% level with gluten and sodium stearoyl-2-lactylate (SSL) additions. Some physical, chemical, and sensory properties of lavaş bread samples were determined. While ash, crude fiber, phytic acid (PA), Fe, K, Mg, and P contents of lavaş breads increased with WBF addition, gluten supplementation caused an increase especially in protein and Ca contents. Leavening process decreased PA contents in the breads compared to raw material, but WBF substitution increased PA contents up to 729 mg/100 g. As a result, the utilisation of WBF in lavaş bread improved the nutrients contents of the bread except PA. The dark colour and slight bitter taste of the WBF affected the sensory score of lavaş bread negatively at 40% substitution level, but the overall acceptability values did not change significantly (P < 0.05) compared to control sample.

The results from monitoring of two endemic species of Uzbekistan flora are shown. The first species examined was Otostegia bucharica B. Fedtsch. (Lamiaceae). This is an endemic species of Uzbekistan which is critically endangered. The second focus of this research was Thesium minkwitzianum B. Fedtsch. (Santalaceae), also an endemic species of western Tien Shan, that grows in the territory of the Chatcal Reseserve.

The presence of genes for resistance to scab (Venturia inaequalis) and powdery mildew (Podosphaera leucotricha) was studied using molecular markers in a sample of 279 apple cultivars from the Czech collection of apple genetic resources. The sample comprised 37 cultivars supposed to have the Vf gene for scab resistance, 97 reference world cultivars and 145 old and local cultivars. Six PCR molecular markers for the scab resistance genes Vf, Vm, Vbj, Vr and Vh and three PCR molecular markers for the powdery mildew resistance genes Pl-w, Pl-1 and Pl-d were used. The marker for the major scab resistance gene Vf was detected in all cultivars supposed to have Vf, except in Romus 1, and in the three small-fruited cultivars Malus Evereste, Golden Gem and Hilleri. The markers of the Vr and Vh scab resistance genes were detected in 22 cultivars in combination with the marker for Vf, in 56 reference world cultivars and in 82 old and local apple cultivars. PCR molecular markers for one or two of the powdery mildew resistance genes were detected in the small-fruited cultivars Malus Evereste, Golden Gem, prof. Sprengeri and Hilleri; and in the larger fruited cultivars Hagloe Crab, Borovinka and Tita Zetei. We did not find markers for the scab resistance genes Vm and Vbj in any of the studied cultivars. They are absent also in the remaining part of the Czech collection of apple genetic resources. PCR molecular markers are useful tools for the identification of resistance genes within apple germplasm collections and can be used to increase the number of sources for disease resistance in breeding programmes.

This review describes sources of structures of non-microspore origin observed in anther and microspore cultures. Various characteristics of these structures may cause a wrong diagnosis of these structures as embryos or cell/tissue clusters of microspore origin. Here we suggest such structures to be named as pseudo-embryogenic structures. The introduction of pseudo-embryogenic structures and their origins could be helpful to distinguish them from true microspore-derived structures. Prompted by certain environmental cues, somatic cells existing as a contamination in immature pollen (microspores) cultures can lead to the formation of 'pseudo-embryos' commonly known as embryoids. The pseudo-embryogenic structures may be classified in the following groups: (i) pseudo-star-like structures; pseudo-multicellular structures; (ii) pseudo-embryos with pseudo-suspensors; (iii) contaminating bacteria appearing as callus colonies; (iv) calli and embryos of somatic origin; (v) giant tetrad-like structures; (vi) anther wall cells. The exact origin of these structures is discussed in this paper, and some recommendations are proposed in order to avoid misinterpretation.

Mulberry (Morus L.) is an economically important tree being cultivated for its leaves to rear the silkworm Bombyx mori. Rearing of silkworm is an art and science popularly known as sericulture; an agrobased cottage industry provides employment to millions in China, India, Korea, Vietnam, etc. Mulberry is a perennial tree that maintains high heterozygosity due to the outbreeding reproductive system. It is recalcitrant to most of the conventional breeding methods, yet considerable improvement has been made in leaf yield and leaf quality. Conventional breeding in mulberry is a tedious, labour intensive and time taking process, which needs to be complemented with modern biotechnological methods to speed up the process. This article enumerates the problems, challenges, constraints and achievements in mulberry breeding along with recent advances in biotechnology and molecular biology to enable mulberry breeders to tackle specific problems more systematically and effectively.

The aim of the study was to select wheat-Aegilops biuncialis addition lines carrying Aegilops biuncialis chromosomes differing from those which were introgressed into the wheat-Ae. biuncialis addition lines produced earlier in Martonvásár, Hungary. In the course of the experiments new wheat-Ae. biuncialis addition lines carrying chromosomes 2U^b, 6M^b, 6U^b; 5U^b, 3U^b, 7U^b; 5M^b, 6M^b and 7M^b were selected. The 2U^b disomic addition line is relatively stable, as 91% of the progenies contain this chromosome pair. The 6M^b disomic addition line proved to be dwarf and sterile, but it still exists as a monosomic addition line. Progenies analysed from the 6U^b monosomic addition line did not carry the 6U^b chromosome. One plant containing the 5U^b, 3U^b and 7U^b chromosomes and one plant carrying 5M^b, 6M^b and 7M^b chromosomes showed very low fertility. Each of the plants produced a single seed, but seeds of the parent plants are still available. Line No. 49/00 carried a submetacentric Ae. biuncialis chromosome pair and the chromosome number 44 has been constant for several generations. After FISH no hybridisation site was observed on the Ae. biuncialis chromosome pair using the pSc119.2 and Afa family repetitive DNA probes, so it was not possible to identify the Ae. biuncialis chromosome pair. However, the use of wheat SSR markers and the (GAA)_n microsatellite DNA probe allowed it to be characterised more accurately. These new lines facilitate gene transfer from Ae. biuncialis into cultivated wheat and the selection of U and M genome-specific wheat SSR markers.

In this contribution actual results of the Czech national ring tests of disease resistance in wheat are presented that are performed at 3-5 locations each year. Special attention was paid to possibilities of increasing resistance to rusts, powdery mildew, Fusarium head blight and brown leaf spot diseases. New sources of resistance to the above-mentioned diseases were detected and described. Achievements and prospects of wheat breeding for resistance to these diseases, as well as to other important diseases and pests (common and dwarf bunt, eyespot and stem base diseases, barley yellow dwarf virus, orange wheat blossom midge) are discussed.

The goal of this study was to compare the growing degree-days (GDD) and predictive equations for alfalfa quality (PEAQ) for the prediction of lucerne quality and to test their accuracy and suitability in the first cut period in Central Bohemia. Several additional stand parameters were verified in order to increase the accuracy of the quality estimate under these environmental conditions. In 2004-2007, the measurement and sampling were repeatedly realized from the late vegetative to the early bloom stage in six replications. For the GDD model across the years, the obtained R² for NDF, ADF and CP were 0.40, 0.57 and 0.65, respectively. It seems that the forage quality response to accumulated GDD was related to the stand development and it could be the reason for low R² across all the years. For the PEAQ model, R² were 0.62, 0.92, and 0.85, respectively. Similarly like in the GDD model, the effect of stand development across the years on changes in the slopes of equations was observed. The accuracy of the model combination was not higher in comparison with the PEAQ model. The count of stems per plant, density of stems per m², dry matter yield and average stem weight improved the NDF content prediction within a four-year period. In these models, variables which represent the stand development should be taken into account.

In association mapping, haplotype-based methods are generally regarded to provide higher power and increased precision than methods based on single markers. For haplotype-based association mapping most studies use a fixed haplotype effect in the model. However, an increase in haplotype length raises the number of parameters in the model, resulting in low accuracy of the estimates especially for the low-frequency haplotypes. Modeling of haplotype effects can be improved if they are assumed to be random effects, as only one parameter, i.e. haplotype variance, needs to be estimated compared to estimating the effects of all different haplotypes in a fixed haplotype model. Using simulated data, we investigated statistical models where haplotypes were fitted either as a fixed or random effect and we compared them for the power, precision, and type I error. We investigated five haplotype lengths of 2, 4, 6, 10 and 20. The simulated data resembled the Danish Holstein cattle pedigree representing a complex relationship structure and QTL effects of different sizes were simulated. We observed that the random haplotype models had high power and very low type I error rates (after the Bonferroni correction), while the fixed haplotype models had lower power and excessively high type I errors. Haplotype length of 4 to 6 gave the best results for random model in the present study. Though the present study was conducted on data structure more frequent in livestock, our findings on random vs. fixed haplotype effects in association mapping models are applicable to data from other species with a similar pedigree structure.

The study aimed at an evaluation of fattening and slaughter performance as well as meat quality of the native Złotnicka Spotted (ZS) pigs and its crosses with Duroc pigs. The experimental material comprised 60 fatteners, divided into three genetic groups of 20 animals (100% ZS, 75% ZS and 50% ZS). The specific character of conservative breeding results in low values of fattening and slaughter performance traits observed in ZS breed. Among the analysed groups, animals with 100% share of ZS genes in their genotype were characterised by low daily weight gains (0.59 kg), considerable backfat thickness (34.96 mm), slight muscle thickness (48.05 mm), and low leanness (41.83%). These parameters were higher in both groups of crosses. Differences between the 100% ZS group and the 50% ZS group were significant for backfat thickness and highly significant for leanness. Acidity and colour parameters analysis showed that meat from all the genetic groups analysed was characterised by a good quality. The highest pH₄₅ values were in the 75% ZS group, and meat from this group had the darkest colour (L* = 49.73) and the highest red colour share (a* = 5.11). Statistical analyses showed that ZS breed retained its original traits through the years of breeding. It was confirmed that meat of Złotnicka Spotted breed is characterised by excellent quality. The results indicate that ZS and Duroc breeds crossing improves fattening and slaughter performance, while maintaining good meat quality in their crosses. Results of this study may also be used by breeders. They indicate that crosses of both the breeds kept in extensive breeding may be successfully used in high quality meat production. Pork from such animals may be a raw material for market niche production, such as regional products. The use of meat from crosses in meat processing may improve both quality of the processed products and efficiency of production based on the native Złotnicka Spotted breed.

Mongolian × Versicolor and common pheasants were investigated. Birds were kept in a confined, environmentally controlled facility without outdoor access and fed ad libitum commercial diets for slaughter pheasants. Body weight was determined at the end of 6, 10 and 13 weeks of rearing, and body weight and body measurements were determined in 16-week-old pheasants. At 16 weeks, 20 pheasants were taken from each genetic group for slaughter. After slaughter, pH₁₅ of muscles was determined and carcasses were dissected. Samples of breast and leg muscles were collected to determine water holding capacity, colour, and sensory properties of meat. Compared to common pheasants, Mongolian × Versicolor hybrids were characterized by similar body weight and body measurements except for length of trunk with neck in females. The carcasses of Mongolian × Versicolor pheasants of both sexes contained more breast muscles, leg muscles, skin with subcutaneous fat and abdominal fat. Differences in the values of these traits were not significant. Significant differences in the composition of carcasses from the groups under comparison were only found for the content of skin with subcutaneous fat and abdominal fat content in females, which were significantly higher (P ≤ 0.05) in Mongolian × Versicolor females. The leg muscles had significantly higher pH₁₅ in Mongolian × Versicolor females and significantly lower (P ≤ 0.05) redness (a*) in males. Compared to the common pheasants, the breast muscles of Mongolian × Versicolor pheasants received lower scores for aroma and tenderness and higher scores for taste, whereas leg muscles had higher scores for intensity of aroma and taste, and lower scores for taste and tenderness.

The breeding value (EBV) of Holstein cattle milk performance from the first lactation was evaluated using a regular Animal Model or by Single-Step Prediction of the genomic breeding value (GEBV). A total of 838 bulls were genotyped using the Illumina BovineSNP50 Beadchip V2. Two overlapping sets of milk performances were evaluated: calving years 1991-2004, with 729 341 lactations and 1 394 487 animals in the pedigree and calving years 1996-2009, with 808 436 lactations and 1 487 608 animals in the pedigree. The older data set included 526 genotyped bulls, in which the daughters' milk performance was known for 210 individuals. All of the genotyped animals were included in the newer data set. Of the young genotyped bulls from the older set, 279 had more than 50 daughters with performance records in the newer set. Genomic relationship matrices (G) were constructed from the allele frequencies of the current genotyped population or by assuming a constant value of 0.5 for all loci. Using current allele frequencies, the correlation of G with the pedigree relationship (A) was 0.74, while it was 0.77 when the constant value was used. G was blended with A with weights of 80 or 99%. The average EBV of the genotyped bulls exceeded the mean EBV of the entire population by 3 SD. Although the number of reference bulls was small, genotyping resulted in an increase of approximately 0.05 in the correlation of the GEBV of young bulls with their results after progeny testing. Only small differences in correlations were found in dependency on the methods used for the determination of G and in dependency on the weight used in blending G with A. Both EBV and GEBV in the older set showed higher correlations with the GEBV of the newer set than the EBV of the newer set.

The present factorial experiment tested the thawed rumen fluid from frozen rumen contents against fresh rumen fluid from the same slaughtered cattle to estimate in vitro degradation of rapeseed meal (RSM) and grass nuts (GN) as two contrasting feeds at various times. Fresh rumen fluid showed higher (P < 0.05) in vitro dry matter (DMD) and crude protein (CPD) degradation than the thawed rumen fluid at most incubation times. Significant differences (P < 0.05) were found between fresh and differently prepared thawed rumen fluids for mean degradation constants (a, b, c) and effective degradability (P_0.02) of feeds. While the thawed rumen fluids had lower (P < 0.01) degradation than the fresh rumen fluid, their degradation values correlated very well (R² ≥ 0.95) with those for the fresh rumen fluid. It appeared that the thawed rumen fluid can be used to predict in vitro degradation of the selected feeds when frequent access to slaughtered or fistulated animals is restricted. Nevertheless it would be vital to improve the activity of thawed rumen fluid prior to testing its suitability for numerous feeds before recommending its routine use to estimate degradation of ruminant feeds.

The study was conducted to evaluate the potential cryoprotective effect of butylated hydroxytoluene (BHT) through post-thaw evaluation of canine semen and its optimal inclusion level. Ejaculated canine semen was extended in TRIS-glucose egg yolk extender containing various concentrations of BHT (0.5, 1.0, 1.5, 2.0, and 2.5mM). Semen was frozen at -196°C using 200 × 10⁶ spermatozoa per 0.5 ml straws and post-thaw evaluation was carried out in terms of sperm motility, viability, plasma membrane integrity, and acrosomal integrity through phase-contrast microscope, supravital staining, hypo-osmotic swelling test, and normal acrosomal ridge, respectively. BHT was found to improve (P > 0.005) all post-thawed semen quality parameters at an inclusion level of 1.0mM in the extended semen. However, higher concentrations than this were found to have detrimental effects.

The aim of this study was to determine the nutrient and energy levels of red clover and lucerne forage. Investigation of forage at different maturity stages of three growths was carried out by chemical analysis, in vitro and in vivo digestibility methods. Generally, maturation caused a significant increase in fibre fractions. With the increasing maturity of forage samples the in vivo, in vitro, and calculated in vivo (in vivo_calcul) digestibilities of organic matter (OM) linearly decreased. The in vitro and in vivo_calcul digestibilities of OM averaged 0.754 and 0.708 for red clover and 0.717 and 0.667 for lucerne, respectively. The in vivo OM digestibility averaged 0.710 for red clover and 0.666 for lucerne. Gross energy (GE), digestible energy (DE), metabolizable energy (ME), net energy for lactation (NEL), and net energy for growth (NEG) averaged 18.12, 12.41, 9.60, 5.67, 5.50 and 18.09, 11.56, 9.01, 5.26, 4.99 MJ/kg of dry matter for red clover and lucerne, respectively. The effect of a vegetative stage on energy values of both forages was diverged for various growth times. When data were pooled across the estimated season, seven cutting-specific equations for descriptions of GE, DE, ME, NEL, NEG, in vitro, and in vivo OM digestibilities were obtained for red clover and lucerne, separately. The red clover model expression gave similar prediction equations for lucerne. It was possible to predict cutting-specific equations with coefficients of determination R² > 0.719 for red clover and R² > 0.400 for lucerne of the variation in GE, DE, ME, NEL, and NEG. The in vitro and in vivo OM digestibility equations were predicted with R² being 0.840 (in vitro) and 0.707 (in vivo) for red clover, and 0.979 (in vitro) and 0.937 (in vivo) for lucerne. The parameters of these specific equations were statistically preferable than the general model expression which included both forages together.

A 2 × 2 factorial design experiment examined the effect of dietary non-phytate phosphorus (NPP) (1.3 and 4.0 g/kg) and 3-phytase (F) (0 and 150 FTU/kg) on the performance indicators of hens, physical parameters of eggs, phosphorus (P) content of the eggshells, and the pH of the digestive tract of laying hens. Two hundred and forty hens (ISA Brown) were housed in enriched cages and fed a wheat-maize-based diet. A significant effect of both NPP and F was found for the yolk colour (P = 0.016) and shell thickness (P = 0.038). The F supplement or higher level of NPP alone and in combination increased the value of the yolk colour and shell thickness. The supplementation of the basal diet with F significantly increased the laying performance, especially with regard to the egg weight and feed conversion ratio. The higher dose of NPP had a negative effect on the egg production, feed intake, and feed conversion ratio. The lower level of NPP (1.3 g/kg) decreased the internal egg quality and shell quality, except for the shell strength. In contrast, the addition of 3-phytase to the diet increased the shell thickness and shell weight. The P content in the eggshells was not influenced by the dietary treatment. The higher level of NPP or F increased the pH in the gizzard to a value suitable for F activity. The hens fed a diet containing 1.3 g/kg NPP achieved a higher performance; moreover, the F supplement at 150 FTU/kg increased the external quality of the eggs.

Relationships between sensory variables, species, feeding systems, and panelists were examined by Procrustes Analysis. Six meat groups considering species and feeding type combinations were evaluated by ten panelists for five sensory characteristics (colour, texture, odour, taste, and acceptability). These characteristics were assessed using a nine-point hedonic scale (9 = extremely enjoy, 1 = extremely dislike). Generalized Procrustes Analysis was performed and 61.11% of the total variability was explained by the first two dimensions that correspond to Factor 1 and Factor 2. The first one accounted for 33.99% and the second for 27.12%. Results showed that pasture conditions were reflected in all sensory characteristics of meat of Hair goat as well as Karakas sheep. This study concluded that meat of sheep and goats reared in pasture conditions was more preferable as concerns sensory characteristics than that of fattening animals or those reared in intensive conditions.

Allometric growth of body macrominerals was examined in slow-growing laying-type cockerels (SG) and in fast-growing male broiler hybrids (FG) during the growing period from hatch to day 22. Allometric coefficients for dry matter, calcium, phosphorus, magnesium, sodium, and potassium in relation to body weight were 1.091, 1.427, 1.383, 1.284, 0.843, and 1.097 for SG chickens and 1.075, 1.276, 1.233, 1.216, 0.943, and 1.144 for FG chickens, respectively. Allometric coefficients describing the relationships of Ca, P, Mg, Na, and K with dry matter weight were 1.302, 1.260, 1.172, 0.772, and 0.998 for SG chickens and 1.185, 1.143, 1.127, 0.878, and 1.059 for FG chickens, respectively. High allometric coefficients for Ca, P, and Mg in both genotypes likely indicate a rapid growth of skeletal tissues which requires an adequate mineral nutrition during this period of growth. The deposition of Ca and P relative to dry matter was higher (P < 0.05) and that of Na lower (P < 0.01) in SG chickens thus suggesting that the relative growth of these minerals may be affected by genotype.

The indicators of follicle development with regard to the growth wave order, the first ovulation, animal parity, and also with regard to the simultaneous presence or absence of a follicular cyst were determined in cows in the course of 60 days postpartum. Follicular dynamics were monitored daily by ultrasonography. The animals were assigned to three groups based on the time of the 1^st ovulation: G1 (n = 9) - the 1^st dominant follicle (DF) ovulated, G2 (n = 10) - ovulation occurred on the 2^nd or later follicular waves, and G3 (n = 5) - no ovulation occurred during the experimental period. G1 animals showed better fertility later (no cyst, less days open, P = 0.07, less hormonal treatment, P = 0.008). The rhythm of follicular wave development was generally similar in all the animals (based on emergence of the first follicular wave, the interval from emergence to deviation, and the number of all follicular waves). Nevertheless, emergence of follicular waves and deviation occurred by 0.5-0.9 day earlier in primiparous than in multiparous cows and in G1 vs. G2, or G3, respectively (in all P < 0.05). DF development was independent of parity as well as group effects, but the maximum size and growth rate (1.2 vs. 0.8 cm/day, P < 0.05) were higher in ovulatory follicles (OF) than in regressive ones (rDF). The presence of a growing cyst decreased the probability of rDF as well as OF development (P < 0.0001). The OF growth rate was faster in the milieu of a stagnating cyst than without any cyst (P < 0.04). Therefore, the development of follicles was dramatically suppressed beyond, but nor before, deviation in the milieu of a growing cyst. Cessation of the cyst growth accelerated the development of OFs. On the contrary, a cystic structure without any significant growth can persist for weeks with no effect on successful follicular development.

The goal of this study was to investigate in vitro multiplication protocols for use with red currant cultivars grown in the Czech Republic. Cultivars Detvan, Vitan and Rotte Höllandische were successfully established in vitro using mercuric chloride in a concentration of 0.15% as a sterilization solution. The overall rate of contamination was 25.7%. Two proliferation media Murashige and Skoog medium (MS) and McCown woody plant medium (WPM) containing 1 or 2 mg/l of 6-benzylaminopurine (BAP) were tested. Initial explants produced new plants in the form of rosettes. Rosettes arose from the base of the initial explants in the form of adventitious bud formation. The shoot number was relatively low and varied between 1.0 and 2.1. Generally, the highest number was obtained for cultivar Rotte Holländische that produced 2.1 ± 0.1 new rosettes on MS medium containing lower concentration 1 mg/l BAP. In contrary, Vitan cv. had significantly lower shoot number ranging from 1.0 to 1.3. WPM medium with a lower concentration of mineral salts proved to be unsuitable for the multiplication of tested cultivars.

Monilinia laxa (Monilia laxa), Monilinia fructicola (Monilia fructicola) and Monilinia fructigena (Monilia fructigena) are the causal agents of brown rot on pome and stone fruits in Hungary. Forty-five isolates collected from different hosts, different years in several orchards were used for characterization of the M. laxa and M. fructigena population in Hungary. The isolates were identified on species level based on morphological and molecular biological methods; out of these 24 were M. laxa, 20 were M. fructigena and 1 was M. fructicola. Populations of the three Monilinia species were studied with microsatellite primers and the degree of genetic diversity within the species was measured. The population structure analysis revealed that genetic diversity within M. laxa subpopulations was H_S= 0.1599, while within M. fructigena subpopulations was H_S= 0.2551. The total genetic diversity was H_T= 0.3846, while genetic diversity between M. laxa and M. fructigena subpopulations was D_ST= 0.1771. No clustering relationship was observed among isolates by the different years or hosts.

In the locality Hnilé Blatá (High Tatras Mts.) the parameters of root plates and the number, length and diameter of the individual root branches in windthrows and standing Norway spruces (Picea abies [L.] Karst.) were measured. Individual root branches were classified to 12 diameter classes according to their diameter measured in the middle of the root branch length. Using random sampling, 21 windthrows were selected. In their neighbourhood, another 21 undamaged trees were selected on the basis of their similarity in aboveground parameters and they were uprooted by a tractor winch. We found out significantly higher mean values of the vertical radius, the average width and theoretical surface of root plates in undamaged spruces. Mean values of root branch frequency in the first six diameter classes (up to 6 cm) were higher in undamaged spruces, but mean values of root branch frequency in the last five diameter classes (12.1-30.0 cm) were higher in windthrows. Mean values of the root branch length in the first six diameter classes were higher in undamaged spruces. Similarly, mean values of the total root branch length were higher in the first six diameter classes in undamaged spruces, but the mean values of the total root branch length were higher in the last six diameter classes (9.1-30.0 cm) in windthrows. Keywords: Norway spruce; stability; root system; windthrow

The differences between oak lepidopteran communities were studied in Slovakia in 1993 and 1994. Sampling was undertaken between April and October on 3 oak species (Quercus robur, Q. petraea, Q. rubra). Biological traits of larvae were examined in order to explain differences in seasonal guilds among oaks. Communities varied in structure and abundance. Species richness in four seasonal guilds (flush, late spring, summer and autumn feeders) had a similar pattern on each of the studied oak species. The guild of flush feeders had the richest species assemblage, followed by the late spring feeder guild and both guilds were significantly richer than the summer feeder guild and autumn feeder guild.

The article describes natural, combined and artificial regeneration on 38 permanent research plots in both Czech and Polish part of the Krkonoše Mts. The attention is paid to species composition, spatial (horizontal and vertical) and age structure of forest regeneration according to different stand and site conditions. Concerning the structure and dynamics of forest stands and their regeneration, the potential and prospects of regeneration according to particular developmental stages and stand types (beech stands; mixed stands: spruce-beech, fir-beech, spruce-fir-beech; spruce stands, stands in the ecotone of the upper forest limit and relict pine woods) were evaluated. In many aspects the plots show several similarities, nevertheless the regeneration in different site and stand conditions show clear differences in dynamics of development. The main differences are result of different ecological conditions, environmental limits and biological characteristics of dominant tree species.

The paper summarizes the main characteristics of a mixed stand during 80-year transformation to the mixed stand with permanent selective structure. The initial main stand was mostly composed of conifers with group arrangement, broadleaves as the reserved trees created the upper storey. Partial opening by thinnings prepared the stand for regeneration. Heavy thinning in 1959 (22% of the growing stock) opened the main stand and released the advance growth of broadleaves. Subsequent stand development was negatively affected by air pollution. Mainly fir and spruce responded to air pollution by deteriorated health condition and increment reduction. Beech and other broadleaves gradually increased their proportion in the stand (64% of the growing stock in 2008). Initial diameter distribution was sinistral, reserved trees affected the frequency of thick trees. Final diameter distribution resembled the model curve for selective forests, the number of thin trees was below the model curve for broadleaved forests with selective structure in these types of localities. Mean increments of individual species changed according to their stand position. Low fecundity of trees, weed infestation and game damage limited natural regeneration, artificial regeneration dominated for the whole time. The complicated structure corresponding to selective forest occurred rarely during the monitored period, the stand was differentiated mainly by spatial arrangement.

Different variants of regeneration felling or different light conditions (total site factor 15-95%) and weed control were evaluated in relation to the 4-year development of individuals of regenerated sessile oak. The regeneration density is not dependent on light conditions. The highest mortality occurs on the open area of clear felling. For a certain time in youth, it is possible to consider oak as a shade-tolerating species. With the increasing light intensity the diameter and height growth of oak seedlings increases proportionally, being the highest at 100% light intensity. However, to support at least medium-fast growth, the species requires minimally 50% light intensity (smaller closed clear-felled areas). On the other hand, more extensive unprotected cleared areas appear to be quite unsuitable at the initial stages of regeneration. The positive effect of weed control on the success and growth of natural regeneration is questionable. We recommend developing the regenerated stand by means of a series of small-area (about ≤ 0.3 ha) two-stage felling with a medium-long regeneration period (15-20 years).

We provide fundamental information about the future development of selected climate elements in relation to anticipated threat to forests in the Czech Republic. All analyses were carried out in relation to four elevation zones with specific potential forest vegetation - up to 350 m a.s.l. (oak dominance), 350-600 m a.s.l. (beech dominance), 600-900 m a.s.l. (beech-fir dominance), 900-1,100 m a.s.l. (spruce dominance). We found out that while the projected increase in mean annual air temperature is almost constant over the Czech Republic (+3.25-3.5°C in the distant future), the frequency of heat spells at lower elevations is expected to increase dramatically compared to higher elevations. The precipitation totals during the vegetation season are projected to increase in the near future by up to 10% and to decrease in the distant future by up to 10% over all vegetation zones. In general, drought is presumed to become a key limiting factor at lower elevations, while increased temperature along with the prolonged vegetation season at higher elevations can be beneficial to forest vegetation. Consequently, northward progression of forest tree species and retraction of the species lower distribution range are a generic response pattern. Such impacts are presumed to be accompanied by changes in the distribution and population dynamics of pests and pathogens. Mainly the impacts on two key forest pests, Ips typographus and Lymantria dispar, are discussed.

The objective of research was, on the basis of the exactly predefined input parameters of upper soil horizons of selected forest soils, to perform accurate measurements of the impact of soil loading by tested forestry machinery using the dynamic penetration test. The measurements by the dynamic penetration test in conditions changed by the wheel traffic of forestry mechanization were performed at three localities of the Křtiny Training Forest Enterprise, Masaryk Forest, a special-purpose facility of Mendel University in Brno. The dynamic penetration test was performed with a lightweight dynamic penetrometer. The methodology of the research is based on assessing the ability of soils to resist dynamic penetration of a rod with a cone, in relation to their lithological composition and physicomechanical properties; the measurement itself is defined by the ISO 22476-2 (2005) standard. Penetrometer measurements were repeated in the period after a harvesting operation and again 6 months later, i.e. in October 2007, April 2008 and October 2008. The results of the field dynamic penetration test and the results of laboratory testing of main soil physical parameters are presented in figures and tables. Besides the naturally variable soil compaction on geologically different substrates, the obtained original results document differences in the impact of particular forestry machines. In conditions of the identical geological substrate, the results indicate that the universal wheeled tractor had a more negative influence on the compaction of surface soil horizons compared to the multi-axle harvester and the forwarder.