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The aim of the study was to assess terrestrial ecosystem development (mainly vegetation and soil characteristics) in the area of a sand mine cast (located in southern Poland) that has been either reclaimed or left for natural succession. A total of 20 sites in a chronosequence of 5, 17, 20 and 25 years were set up in two site categories: reclaimed and non-reclaimed sites. Selected properties of initial soils and features of vegetation were measured and they included carbon accumulation in soil; biomass and diversity of communities were also estimated. Next, based on carbon accumulation, the energy trapped in ecosystem components was estimated. Although the results of plant community investigation did not show the same distinct differences between site categories, the case study suggests that reclamation significantly accelerates ecosystem development. In comparison with spontaneous succession, the complete forest reclamation was found to increase the amount of carbon accumulation, thickness of humus horizon, and energy trapped in soil organic carbon and plant biomass in the developing ecosystem 2-3 times and nitrogen accumulation 5 times.

The impact of blue spruce (Picea pungens) and reed Calamagrostis villosa) cover on quantity and quality of upper soil layers was investigated. The research was conducted in the Jizerské hory Mts., Czech Republic (altitude 880 m, acidic spruce forest site type - 8K). Mean weight of dry matter of holorganic horizons was similar under both variants. Totally, there were accumulated 153 t/ha of dry matter of humus horizons in blue spruce and 174 t/ha in reed. Soil pH (KCl) varied from 3.7 to 3.2 under blue spruce stand and from 3.6 to 3.3 under reed. The differences of concentrations of nutrients (P, K, Ca, Mg) were not found significant either. Only L horizon showed significant differences: there were higher values of cation exchangeable capacity (T) and higher content of exchangeable bases (S) under reed. We found very similar forest-floor humus properties under both species. Therefore we can not state worsening of the soil conditions under blue spruce compared to areas covered with tested forest weed species.

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.

This paper deals with the Reynoutria × bohemica and Reynoutria japonica under conditions of the Czech Republic. It evaluates the impact of soil, weather conditions and various terms of harvest (autumn, spring) on the yield, dry matter content, phytomass loss, ash content, and basic elements content change in plants. Heavy metals content was determined in soil where plants were grown and consequently in plants themselves. The average yield of dry matter at the fully closed stands of Reynoutria japonica were 9.06 t/ha in autumn, Reynoutria × bohemica from 13.23 to 21.41 t/ha, according to the site. The yield losses within the winter period were found on average 42% for Reynoutria japonica and 34% for Reynoutria × bohemica. The moisture decrease of Reynoutria japonica was found from 68% in the autumn to 24% in the spring, and of Reynoutria × bohemica from 67% to 23%, respectively. Decreased content of nitrogen, phosphorus, potassium, calcium, and magnesium in the knotweed phytomass was found during the latter (spring) harvest periods in comparison with the earlier harvest periods. Decreased elements content in phytomass during the latter harvest period (spring) increases the phytomass quality as a fuel from both aspects - technical and emissions generation. The ash content in plants varied according to the site, on average from 3.12% in Ruzyně to 4.6% in Chomutov. None of the heavy metals monitored in knotweed plants reached the maximum admissible values determined for the food or feed purposes in the Czech Republic. From the results of combustion experiments, it is evident that Reynoutria × bohemica is a good fuel. Energy sorrel shows the extreme CO concentration in flue gases in comparison with other monitored fuels. According to the ČSN EN 12809 (2001) standard it does not meet even the third class of requirements. On the contrary, knotweed and wood bark fulfill the requirements for the first class. The surprising fact is that both of these fuels show the lower level of CO emissions, than the wooden briquettes. Concentrations of nitrogen oxids are comparable with biofuels, except of wood, and probably are related to the nitrogen content in heating material.

The price of agricultural land and its value are of importance when forming the production potential of agricultural enterprises. The price of land marked an irregular development in the period 2006-2007 having increased in the majority of the EU states. The proportion of rent to the market price of land referred to as the capitalization rate kept varying within the range of 2-3%. The price of a site should, besides the land rent, also reflect the interest on the land rent received. The price of agricultural land with respect to the land rent manifests relatively important price inertia. This inertia in connection with a high growth rate of land rent results in the unrealistically high interest rate. Such situation is an evident advantage for land owners and is, on the contrary, a disadvantage for the tenants of the agricultural land. To make the interest rate realistic means especially stabilizing the land rent with low growth rates. These growth rates are different for different states. In general it can be maintained that the relative increase in land rent should not surpass 4%, exceptionally 6%.

Chloroplast engineering (or chloroplast transformation technology, CTT) is a strategy consisting of inserting a transgene into the chloroplast genome of a plant instead of its nuclear genome. CTT brings advantages such as control of the site of gene insertion, high rates of transgene expression and protein accumulation, lack of transmission of the transgene via pollen due to the fact that plastid genes are maternally inherited and an absence of epigenetic effects. Tobacco remains the species most amenable to CTT to date, although chloroplast genetic engineering has also been achieved successfully in crops such as maize, tomato, cotton, potato, rice and sugar beets. Improving agricultural traits such as herbicide and pathogen resistance, resistance to drought, salt tolerance and phytoremediation potential are all promising applications. Molecular pharming is another area of chloroplast engineering with high potential; the production of a wide range of products such as vaccine antigens, pharmaceutical proteins (human somatotropin, human serum albumin, human interferon, monoclonal antibodies) and industrial proteins (avidin, beta casein, liquid crystal polymers, xylanase, anthranilate synthase) is economically beneficial in comparison with bacterial cultivation or animal cell cultures. This review summarises the current status of CCT and its potential economic impact from the viewpoint of high levels of transgene expression and high accumulation of foreign proteins.

Plant pathogenic species Pseudomonas corrugata and P. marginalis were detected and determined in collapsed tomato plants in rockwool slab hydroponic culture in southern Moravia, Czech Republic. Surprisingly, P. marginalis was also determined before planting in apparently healthy grafted tomato transplants grown in hydroponic culture. Moreover, non-pathogenic P. fluorescens, P. putida, P. synxantha, and Stenotrophomonas malthophilia were identified. The Biolog Identification GN2 MicroPlate™ System System (Biolog, Inc., Hayward, USA) was used for identification of bacterial isolates. Cultures of P. corrugata and P. marginalis were used in a greenhouse pathogenicity experiment. Seven weeks old tomato plants of cv. Moneymaker grown in sterilised perlite were inoculated into the stem with a hypodermic needle at one point above the cotyledon node. In inoculated tomato plants, disease symptoms were observed that included external and internal dark brown lesions around the inoculation site, watering and collapse of pith and sometimes also vascular browning and wilting of leaves. In comparison with P. marginalis, P. corrugata appeared to be a much stronger pathogen. Both tested Pseudomonas species were recovered from inoculated tomato plants. P. corrugata was found to move both upwards to the apex of the stem and downwards from the site of the inoculated stem into roots. When inoculated into potato tuber slices, some tomato strains of P. marginalis, P. fluorescens, P. synxantha, and Pseudomonas sp. produced soft rot. However, other strains of the same species were not able to macerate the potato tissue. It is concluded that P. corrugata and P. marginalis can be associated with the collapse of tomato crop in soilless culture grown in a greenhouse. This is the first report on P. corrugata in tomato plants in the Czech Republic. The role of plant pathogenic bacteria, fungal root rot and vascular pathogens and Pepino mosaic virus in the collapse of tomato plants is discussed.

The paper evaluates the quality of revitalization treatments (fertilization and liming) carried out in selected areas within Forests of the Slovakia (state enterprise) during the year 2008. Revitalization treatments were carried out in declining Norway spruce forest stands in different site conditions. Full-scale aerial technology (helicopter and crop duster) was applied. The aim of the study was to find out the total amount and its variability of both fertilizers and dolomitic limestone after their application. The analyses revealed significant differences between the amount of fertilizer and dolomitic limestone which was applied to selected areas and the required amount (norm). As for fertilization, the largest difference was found in magnesium (Mg) on Šaling area (the amount of magnesium reached only 7% ± 0.5 of the norm) and in zinc (Zn) on Ľadová area (only 8% ± 1 of the norm). The required amount according to the norm was approximately met in boron (B) on Ľadová area (65% ± 10 of the norm). Yet, a significantly lower amount of fertilizers than the required one was revealed on all selected areas. After the application of dolomitic limestone to Liptovská Teplička area the significantly lower amount than the required one was found out (72% ± 12 of the norm). On the other hand, the significantly higher amount of dolomitic limestone than the required one was determined on Smolník area (143% ± 27 of the norm). Results also show the huge spatial variability of both fertilizers and dolomitic limestone on all selected areas (from 40% up to 100% between collecting places, and up to almost 170% between collectors within the collecting places). Such high variability of applied fertilizers and dolomitic limestone and the lower total amount than the required one will influence the effect of revitalization treatments.

The present paper compares the growth of parent trees and potentially stress-tolerant mixtures of clones of Norway spruce (Picea abies [L.] Karst.) progenies coming from a specific locality near the Černá hora peat bog in the Krkonoše Mts. Growth was studied in generative ortet plantations in Trutnov locality and in a mountain ortet plantation Lesní bouda, in the 1^st generation clone plantation Benecko and in the 2^nd generation clone plantation in the Černohorská rašelina locality. In the latter locality chlorophyll fluorescence and water losses during controlled desiccation were also measured in selected clones compared to control (generatively propagated) spruces. Partial data acquired until now prove the good growth dynamics and physiological state of some clones in extreme climatic conditions indicating that cuttings were taken from vital parent trees growing in exposed mountain localities. Growth relations among the clones were identical in all evaluated localities. The growth of the 2^nd generation clone plantation has been markedly influenced by plantation and specific site conditions until now. The mutual interaction of clone growth and site conditions can change in time and therefore the study of clone plantations will continue in the years to come.

The present paper analyses the problem of calculation of the average number of hours in a year during which air temperature is lower than a preselected limiting level. A method for estimating the number of hours in situations where only the minimum, average, and maximum daily temperature data are available has been suggested and tested. The work encompassed 30 sites in the Czech Republic at different altitudes and with different average temperatures, using weather data from the 1961-2000 period. The results are presented in the tabular form. It is shown that interdependence exists between the number of hours with temperatures lower than a preselected limiting level and the average yearly temperature at the specific site. For instance, temperatures below 15°C during a typical year at a site with an average yearly temperature θyr (°C) within the range of 2.8°C to 9°C can be expected (coefficient of determination 0.986) for a time τ (h) calculated from the quadratic equation τ = -12.992 × θyr 2 - 116.6 × θyr + 8,483.

Like in other types of forests the greatest changes in the soil of floodplain forest stands occur during their regeneration. These changes are manifested as changes in the content and dynamics of organic matter in the soil. Research was conducted in oak and ash floodplain forests in the eastern part of Croatia and in southern Moravia in the Czech Republic. The results showed that the type and extent of these changes depended, in addition to environmental factors, also on the technology of forest regeneration. The natural regeneration of oak in floodplain forests of Spačva (eastern Croatia) protects soil from dramatic changes in soil by successive regeneration felling and that it retains the plant cover permanently. The weight of organic matter on the soil surface is increased after regeneration till the period when the effect of thinning becomes evident (about 70 years). In the surface mineral layer of soil the pH value increases after shelterwood felling. Stand regeneration with clear-cutting results in a rapid change in the conditions of surface humus accumulation and decomposition. The process of organic residue accumulation is interrupted in the clearings. In the preparation of soil/site by ploughing, the concentrations of nitrogen and carbon slightly decrease. The management impact depends on the method of site preparation for the establishment of a new stand. The selection of a method of the floodplain forest regeneration (particularly of oak) is markedly dependent on actual ecological conditions and on ecological and historical experience of the given region.

One of the key goals of the Thematic Strategy for Soil Protection is to maintain and improve soil organic carbon (SOC) stocks. A decline of SOC stocks is politically perceived as a serious threat to soil quality and functions. A suitable tool for acquiring the information on SOC stock changes is modelling. The RothC-26.3 model was applied for long-term modelling (1970-2007) of the SOC stock in the topsoil of croplands of Slovakia. Simulation results show a gradual increase in the SOC stock in the first phase of modelling (1970-1995) mainly due to higher carbon input in the soil. A significant linear correlation (r = 0.4**, n = 275) was found between carbon input and the final simulation of SOC stock. A close relationship between the SOC stock and soil production potential index representing the official basis for soil quality assessment in Slovakia was also determined and a polynomial relationship was found which describes the relation at the 95% confidence level. We have concluded from the results that balanced or positive changes in the SOC stock dynamics that are important for sustainable use of soils could be influenced positively or negatively in Slovakia by political decisions concerning the soil management. Moreover, the soil production potential index can be used as soil quality information support for such decision-making.

The Bruks mobile chipper was tested for chipping extracted non-merchantable stemwood at the roadside in Pine plantation in Victoria. The elemental time study method was used to evaluate the system productivity. The productivity, cost, biomass yield, remaining slash, chip quality (size classification and energy content), and fuel and energy consumption were analysed. Chipping extracted small logs at the roadside yielded a productivity of 43.88 GMt.PMH₀^-1 (19.4 BDT.PMH₀^-1). The average cost was about 16.96 USD.GMt^-1 (38.36 USD.BDT^-1).

Relatively little is known about potassium leaching losses following harvest of silage maize. While direct negative impacts on the environment are unlikely, losses of K with leaching need to be known for accurate balancing, especially on coarse textured soils, where K can be a critical element. In a four-year field experiment the effects of fertilizer forms (inorganic, cattle slurry and pig slurry) and four levels of N input (0, 80, 160, 240 kg N/ha) with corresponding amounts of K on the nutrient balances and leaching of K from silage maize grown on a sandy soil were investigated using suction cups. After four years, surplus of K from cattle slurry led to higher lactate-soluble K in the topsoil. Potassium leaching differed between years with different amounts of rainfall during winter. Annual leaching losses of K increased with N and K input and amounted to 38 kg K/ha, while fertilizer form had no significant effect. Losses of K increased with increasing N leaching (R² = 0.69). We conclude that in maize production on coarse textured soils and under conditions of high N leaching (86-152 kg N/ha), K leaching can be large (6-84 kg K/ha) and constitutes a relevant part of K balances (-84 to +127 kg K/ha).

Coenurosis caused by Coenurus cerebralis, the larval stage of Taenia multiceps, particularly affects sheep and goats. In this case report, two coenurus cysts were detected under the lumbar spinal cord (outside the CNS) in a goat. We first described cysts in the macro- and micro-morphological examination. The cysts were identified as C. cerebralis on the basis of the arrangement of scolices and the number and size of hooks in the scolices. The morphology of the larval cyst was similar to that of T. multiceps: the scolices had four suckers and a rostellum with a double crown of hooks. The hooks and hooklets were 178 and 132 µm in length, respectively. T. gaigeri may be synonymous with T. multiceps. This may reflect a different host response to the parasite in goats. The difficulty of making a species identification in C. cerebralis or C. gaigeri based on their morphology is discussed.

The main aim of this study was to determine the intensity of hydrophobic/hydrophilic components of the soil's organic matter as well as its hydrophobicity. Non-destructive Fourier Transform Infrared (FTIR) spectroscopy was used for the diagnosis and characterization of the basic classes of the chemical groups (hydrophilic and hydrophobic components) from which the organic matter in the soils is formed. Soil samples (depth 0-30 cm) were taken from the topsoil of the 70 sampling sites from the experimental field at Prague-Ruzyne (Czech Republic) during 2007-2009, where a conventional soil tillage technology was used. It was found that the variability of the intensity of the hydrophobic components is greater (27.6%) than that of the intensity of the hydrophilic components (6.2%), which correlated significantly with the C_org (r = 0.58; P < 0.05) and N_t (r = 0.65; P < 0.05) in the soil. It was proven that the soil samples with a higher proportion of coarse grains are more hydrophobic than those with higher proportions of clay. Data about soil hydrophobicity can help to evaluate the soil quality parameters as well as the soil fertility.

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.

Earlier breeders used phenotypic selection based on morphological characteristics to improve tree varieties. These selections often take many cycles of breeding and backcrossing in order to place desired characteristics. But today the knowledge has paved the way for a much deeper understanding of the mechanics of cell biology and the hereditary process itself. Breeders are presented with numerous possibilities of altering the behaviour of existing varieties. Linkage between molecular markers can be translated to genetic linkage maps, which have become an important tool in plant genetics. They may choose to use marker-assisted approaches in order to facilitate the selection of favourable combinations of genes that occur naturally within a tree species.

Driven by a combination of pedagogical, ethical and economic factors, the use of simulation technology and other alternatives to traditional training methods has become increasingly common in veterinary education as a means to teach basic and advanced concepts along with technical skills. When paired with well-structured and supervised clinical training on animal patients, these modern methodologies help educators fill gaps left by conventional methods, reduce and replace the consumptive use of live animals, and ultimately result in the graduation of more confident and proficient veterinarians, veterinary technicians, and allied health personnel. This article surveys an array of the simulation methods currently available for veterinary education and how they integrate with and enhance standard curricula.

The aim of the study was to describe the distribution of total mercury in the tissues of fish originating from important Czech fishing locations and to determine the level of methylmercury as a percentage of total mercury (Hg speciation). At six important fishing locations a total of 144 fishes of 13 species were caught and analysed. Samples of muscle, liver, gonads and scales were analysed for total mercury and in the case of muscles for methylmercury concentrations. Total mercury was determined by AAS using an AMA 254 analyser, and methylmercury determination was performed by GC/ECD using a GC-2010A chromatograph. Total mercury concentrations in muscle and other tissues of all the fish from all fishing locations were below 0.5 mg/kg, with the exception of 6 asps (Aspius aspius). A significant (P < 0.05) correlation was found between the total mercury concentrations in scales and other tissues. Methylmercury made up about 46-100% of total mercury in muscle. The overall results confirmed the good hygienic quality of fish from important Czech fishing locations.

This study was carried out to detect the distribution of antibiotic-resistant genes in Escherichia coli isolates from slaughtered commercial chickens in Iran by PCR. The investigated genes included aadA1, tet(A), tet(B), dfrA1, qnrA, aac(3)-IV, sul1, bla_SHV, bla_CMY, ere(A), catA1 and cmlA. According to biochemical experiments, 57 isolates from 360 chicken meat samples were recognized as E. coli. The distribution of antibiotic-resistance genes in the E. coli isolates included tet(A) and tet(B) (52.63%), dfrA1, qnrA, catA1 and cmlA (36.84%) and sul1 and ere(A) (47.36%), respectively. Nine strains (15.78%) were resistant to a single antimicrobial agent and 11 strains (19.29%) showed resistance to two antimicrobial agents. Multi-resistance which was defined as resistance to three or more tested agents was found in 64.91% of E. coli strains. The results indicate that all isolates harbour one or more of antibiotic resistance genes and that the PCR technique is a fast, practical and appropriate method for determining the presence of antibiotic-resistance genes.

This study aims to explore the optimum nitrogen (N) application method by analyzing effects of variable N application stages and ratios on the N absorption and translocation of high-yield summer maize (DH661). The study included field experiments and ¹⁵N isotopic dilutions for pot experiments. Results showed that the yield was not increased in a one-off N application at the jointing stage. The uptake of fertilizer-derived N in the grain increased with the increasing of N applied times. Compared to a single or double application, total N uptake (N_up) and biomass increased significantly by supplying N at the six-leaf stage (V6), ten-leaf stage (V10) and 10 days after anthesis in ratios of 3:5:2 and 2:4:4. The fertilizer-derived recovery rates were 67.5% and 78.1%, respectively. The uptake and utilization of fertilizer-derived N was enhanced by increasing the recovery rate of N supplied after anthesis, and reducing the absorption of soil-derived N. Therefore, the 2:4:4 application ratios was the optimal N application method.

Water and nitrogen managements are both very important to increase crop yield. An experiment was carried out in split plot design to study the effects of urea types (normal urea and coated urea) and irrigation on soil and fertilizer nitrogen use in maize (Zea mays L.) field in 2006 and 2007. Irrigation was used as main plot, and urea types were used as split-plot. Two irrigation levels, no irrigation in the whole growth duration and 85 mm irrigation at the blister stage, were designed. There were five nitrogen treatments, which were no nitrogen used as control (N0), normal urea 75 kg N/ha (N1), normal urea 150 kg N/ha (N2), coated urea 75 kg N/ha (C1) and coated urea 150 kg N/ha (C2). The results showed that, at the same level of irrigation and nitrogen, the soil nitrogen contents of the treatments with coated urea (CU) applied were higher in 0~40 cm soil layers, but lower in deeper soil layers, than those with normal urea (NU) applied. Irrigation increased the nitrate losing, but the nitrate loss of CU was lower than those of NU. Using CU with irrigation could increase the nitrogen uptake by maize, and more nitrogen was transfered to grain. At the same nitrogen level, CU had higher N recovery efficiency but lower soil N dependent rate than NU. When applied with CU, the nitrogen release rate was lower and the nitrogen was quickly absorbed by maize, which reduced the risk of nitrogen loss and increased the use efficiency of soil and fertilizer nitrogen. These results suggest that coated urea combined with deficit irrigation should be applied for high yield and nitrogen use efficiency of maize on the North China Plain.

A three day-old Japanese black calf was admitted with a history of abdominal distension and absence of defecation. Dilated loops of the small intestine and hypoplasia of the colon and rectum was observed upon a contrast radiographic examination in the standing position. At necropsy atresia coli with undeveloped rectum and patent anal opening was found. We conclude that a contrast radiograph in the standing position is useful for diagnosing atresia coli in such cases.

Studies were undertaken to investigate the composition, structure and diversity of four different types of North Mongolian montane forest near the southern border of the taiga. These forest types, classified as willow-poplar, larch-birch, spruce-fir and Siberian-pine forests, were found to be significantly different with respect to the elevational gradient. In the study area, two fire regimes could be distinguished at lower and drier elevations, frequent surface fires resulted in less diverse forests comprising coniferous species, which in their adult form were found to be fire-resistant, burn-colonizing and light-demanding deciduous tree species. In contrast, the forests colonizing the moist, higher elevations and shaded slopes had a higher diversity of tree species with greater basal area, higher proportion of deadwood, and more regenerating trees; here the coniferous shade trees experienced infrequent but destructive treetop fires. Overall, our results showed that the four forest types differed in composition according to the tree species, diameter and height classes.

This paper contains the information about some principles of sustainable forestry which are still relevant in the world. In 2002, Lithuania started research on the nutrient balance in forest ecosystems when the forest fuel is harvested. The consequences of the intensive forest fuel harvesting on the forest ecosystem were analysed. At the same time, the experiment on the compensatory wood ash fertilizing was established in Lithuania. After the initial calculations, having the experimental data, the Ministry of Environment of the Republic of Lithuania has initiated the preparation of the Recommendations for compensating wood ash fertilization in the forests. This review briefly systematizes and analyses the main results of the related research and some ideas for the future studies are also presented.

Transmissible venereal tumours (TVT) are normally seen on the genitalia of both male and female dogs, and at times may be observed on extra-genital sites such as lips, oral mucosa, and peritoneum, or in organs such as the tonsils, eye, liver, spleen, kidney, lung, and musculature. The present communication deals with two rare cases of primary extragenital TVT involving the mammary glands of dogs and their pathology and immunohistochemistry. The study indicated that apart from routinely used markers such as vimentin, p53, PCNA, Ki-67 and c-myc, the oncogenes Rb and cyclin D1 proved to be novel markers of TVT in dogs. To the authors' knowledge, this is the first report of extra-genital mammary TVT in canines.

Changes in genetic diversity of peas bred in the Czech Republic and in former Czechoslovakia since the mid-20^th century were analysed using 38 molecular marker loci, including retrotransposons and microsatellites, differentiating a total of 84 alleles. Both marker types were comparably effective in revealing the genetic diversity, with a high correlation (r = 0.81), although the pairwise genetic distances of each marker type differed. In total, 175 accessions, selected from the Czech pea gene bank collection and representing the pea cultivars collected or bred in the country, were divided into three groups according to their date of sampling or variety registration. The first group contained 70 old cultivars and landraces collected prior to 1961. The second group contained 46 cultivars released from 1961 to 1980. The third group contained 59 cultivars released between 1981 and 2004. In spite of the decline in several diversity measures, differences in allele frequencies and even allele loss in three microsatellite loci were recorded over the 70-year period, while these differences between the groups were not statistically significant. In addition, genetic heterogeneity was detected in 29 accessions (15%). This indicates that although no genetic erosion could be observed since then, it is important to monitor the genetic diversity, furthermore it highlights the vital role of germplasm collections for the crop diversity conservation.

The literature linking Bt maize versus non-Bt maize and the changes in the fungal microflora spectrum and in the mycotoxins content have been summarised. The European corn borer reportedly promotes the infection of maize by Fusarium spp. Stalk and ear rots caused by Fusarium spp. are often related to mycotoxin accumulation in maize kernels. As a result, food and animal feed from maize are more severely contaminated with Fusarium mycotoxins: e.g. fumonisins (FUM), deoxynivalenol (DON), and zearalenone (ZEA). Mycotoxins in field maize lead annually economic losses of hundreds of millions of dollars in all regions of the world. The insecticidal proteins in genetically modified hybrid Bt maize reduce insect damage caused by certain Lepidopteran larvae, which in turn can reduce the infection of the grain by the mycotoxigenic fungi. Where such insect damage is a major factor in mycotoxin contamination, Bt maize can lower mycotoxin levels in many cases. The protection of maize plants against insect damage (European corn borer) through the use of Bt technology seems to be one of the ways to reduce the contamination of maize by Fusarium species and mycotoxins.