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The present report describes a series of adverse events recorded in gilts and sows at a pig-breeding farm. The animals were listless, had poor appetite and dyspnea, sneezed and coughed, but were afebrile. Subsequently, an increased number of spontaneous abortions occurred, eventually rising to 50 times their average number. The usual infective causes of abortion were ruled out by diagnostic testing; however, the results of drinking water analysis pointed to over-chlorination, with a free chlorine residual concentration of 2.11 mg/l, caused by failure of the chlorinator dispenser connected to the water supplying system seven days previously. Analysis of data on reproductive parameters indicated that the over-chlorinated drinking water directly induced an increase in the number of abortions after only two days of consumption, whereas 7-day consumption of over-chlorinated drinking water had a direct delayed effect on the increased return to oestrus in gilts and sows, and on the increased percentage of stillborn piglets (all P < 0.001). The consequential indirect delayed effect manifested itself as a reduced number of farrowings in gilts and sows, and a lower total number of piglets born (both P < 0.001).

The article describes the impact of the Sectoral Operational Programme Agriculture and Rural Development and the Rural Development Plan 2004-2006 on the rural development in 2004-2007. In addition to the implementation analysis of these programming documents, the article also describes territorial distribution of direct subsidies and state aid over the monitored period of 2004-2007. A summarized overview is given for the drawdown of all types of subsidies and their proportionate amounts. The evaluation of all subsidies has shown that most of them were paid to the Northern and Eastern parts of Slovakia, due to the agroenvironmental and direct payments (mostly LFA). The article also describes, in quantitative terms, the social and economic impact of investment subsidies from the Sectoral Operational Programme Agriculture and Rural Development and the Rural Development Plan 2004-2006, based on the monitoring indicators of result and impact. The comparison of the socio-economic development of the beneficiaries and non-beneficiaries of investment subsidies from the SOP and RDP has shown a faster growth in income of the beneficiaries, as well as a faster growth of labour productivity. Also, the subsidies significantly helped to reduce the decrease in employment and/or helped to maintain the employment in agriculture.

The paper analyses the machinery costs associated with the performance of the individual operations when growing and harvesting the legume-cereal intercrops (LCI). For this purpose, a database of costs associated with the individual operations concerning the LCI growing has been created. This database is continuously updated in such a way that it enables to estimate variable costs associated with the individual LCI growing and harvesting operations. The authors followed up and analysed the process of growing and harvesting the LCI as a fodder crop and preserving the harvested material in the form of haylage and silage or for grain (both wet and dry). The analysed data were obtained in the course of the individual operations of machinery used in the individual technologies of establishing and growing of the LCI under the conditions of organic farming.

Total number of 104 canned soft drinks collected from several regions in Turkey were analysed. The purpose of this study was to determine the levels of heavy metals in the drinks commonly consumed in Turkey. Quantitative determination of heavy metals: arsenic, copper, zinc, cadmium, and lead in all samples was carried out by ICP-OES (Inductively Coupled Plasma-Optical Emission Spectrometry) method. The mean levels (± SE) of arsenic, copper, zinc, cadmium, and lead were found to be 0.037 ± 0.002 mg/kg, 0.070 ± 0.009 mg/kg, 0.143 ± 0.012 mg/kg, 0.005 ± 0.0003 mg/kg, and 0.029 ± 0.002 mg/kg, respectively, in soft drinks. Our data revealed that arsenic, copper, zinc, cadmium, and lead mean levels found in all soft drinks, collected from several regions in Turkey, were within the Turkish Food Codex (TFC) values.

A study was conducted on the effect of two single practices, including soil tillage and returning straw to soil, and their interaction on soil porosity of maize-wheat cropping system. Field experiments involved four tillage practices, including conventional tillage (C), zero-tillage (Z), harrow-tillage (H) and subsoil-tillage (S), with straw absent (A) or straw present (P). Total porosity, capillary porosity and non-capillary porosity of soil were investigated. The results showed that the soil total porosity of 0-10 soil layer was mostly affected; conventional tillage can increase the capillary porosity of soil, but the non-capillary porosity of S was the highest. Returning of straw can increase the porosity of soil. Through the analysis of affecting force, it can be concluded that interaction of soil tillage and straw is the most important factor to soil porosity, while the controlling factor to non-capillary porosity was soil tillage treatment.

The composition of high molecular weight (HMW-GS) and low molecular weight (LMW-GS) glutenin subunits was examined in a collection of 86 Czech registered winter wheat varieties. These proteins were analyzed by sodium dodecyl sulphate polyacrylamide gel electrophoresis. An inter-varietal polymorphism of the HMW and LMW glutenin subunits was detected. Twenty-one different patterns for HMW were identified, and eighteen for the LMW-glutenins. The different alleles encoded at the six glutenin loci were determined. Three, six, and four alleles were observed, respectively at the Glu-A1, Glu-B1, and Glu-D1 loci (encoding high HMW-GS). Three, eight, and three alleles of LMW-GS were found, respectively, at the Glu-A3, Glu- B3, and Glu-D3 loci. The evaluated varieties were split into four categories of baking quality, and these variety groups were analyzed for the presence of different HMW-GS and LMW-GS alleles. While the alleles Glu-B1c (7+9), and Glu-D1d (5+10) were detected exclusively in bread wheat varieties, the alleles Glu-B1d (6+8), Glu-D1a (2+12), and Glu-A3e/f only occurred in those varieties that are not suitable for bread-making.

The research reported in this article attempts to address the ammonia problem by quantifying the effect of several variables on ammonia concentrations and emissions. These variables include litter temperature, litter age and ventilation rate. Data was collected in a commercial tunnel-ventilated grow-out facility with deep litter, designed for 25 000 broilers, during 6 consecutive flocks. Birds were housed from hatching to approximately 40 days of age. Litter temperature and litter age were positively correlated (P < 0.0001) with the production of ammonia gas. The amount of ammonia emissions increased with the litter age (P < 0.0001) as a consequence of both the increased ammonia concentration and the ventilation rate (P < 0.0001). The lowest concentrations of NH3 were observed in a "summer" period, although ammonia emissions tended to be higher just in summer months because of a higher ventilation rate. The elevated levels of ammonia in winter were attributed to the lower ventilation rate during cold weather. After the evaluation of ammonia emissions it can be concluded that during the grow-out period of broilers kept on renewed litter there is an average loss of 6.18 g ammonia per bird and/or 0.043 kg of ammonia per bird yearly. The increase in litter temperature during grow-out periods is a process which could be controlled to prevent excessive ammonia volatilization from housing facilities.

The occurrence of 10 lower taxa within species Pyrus pyraster L. (Burgsd.) was confirmed in Slovakia. Among 507 of the evaluated plants on 64 localities, there were recorded 2 sub-species of the wild pear - Pyrus pyraster subsp. pyraster and Pyrus pyraster subsp. achras . Subspecies pyraster was represented by 4 varieties (pyraster, elongata, pénzesiana, brachypoda ) and 5 forms (populifolia, cordifolia, rhomboidea, ovata, slovenica ). All lower taxa were visually classified according to the leaf and fruit characteristics. Numerical classification based on discriminant analysis according to quantitative traits was done. Some discrepancies were found up to 16.7% between visual and numerical classification on particular levels of the lower taxa identification.

The influences of long-term flooding and Phytophthora alni subsp. alni infection on the growth and development of 4-year-old Alnus glutinosa (black alder) saplings were investigated. The black alder saplings were divided into four groups and then subjected to combinations of both factors - flooded and inoculated with pathogen, flooded non-inoculated, non-flooded inoculated, and control. The biomass of the living roots and actinorrhizae, increase in stem length, length of leaves, rate of chlorotic foliage, amount of foliage biomass and length of stem necrosis were assessed after seven weeks. Both factors, flooding and P. alni infection significantly affected the black alder. In addition, a significant effect of interaction was observed. The inoculated flooded group had a substantially lower biomass weight of living roots, actinorrhiza and leaves than the other groups. The necroses caused by the pathogen in the flooded group were more extensive than those in the non-flooded one. These findings demonstrate that the simultaneous incidence of stress caused by flooding and P. alni infection is highly dangerous for black alder.

Soybean cultivation in many zones of India shows occurrence of native rhizobia besides other exotically adapted strains. In the current study, 22 rhizobial isolates (recovered from 12 different soybean growing sites) and 8 reference strains were selected for biochemical and metabolic characterization. Of 22 isolates, 18 were recovered as fast growing isolates while the rest were slow growing based on bromothymol blue (BTB) test. Unlike earlier belief that rhizobia have no ability to grow on glucose peptone agar medium, in this study, some isolates and some reference strains grew well on this medium. Similarly, when all the isolates were subjected to ketolactose test, some of the isolates were found to show growth on the medium. In contrast, based on C-utilization pattern (15 carbohydrates) a remarkable metabolic diversity was observed among the rhizobial isolates recovered in the study. The clustering and matching analysis showed that most of isolates were matching with slow growing reference strains, a few were with fast growing reference strains and some were found to be unique and hence not matching with any of reference strains. Such analysis suggests the occurrence of metabolically distinct types of rhizobia besides commonly known types (B. japonicum, B. elkanii and S. fredii) of soybean rhizobia and further validation is suggested through 16SrRNA gene sequencing technique.

To assess the different origins of Portuguese grapevine varieties, we used six nuclear and four chloroplastidal microsatellites as molecular markers, in order to compare the genetic structure of native wild-vines with native grapevine varieties. Both native subspecies have a great diversity, and a high interrelationship across the six nuclear microsatellites. Although identical numbers of alleles were found in each population, their distribution was different in the vinifera and sylvestris subspecies. Portuguese wild-vines have only chlorotypes A and B; A being the most frequent. The fifty-seven analysed Portuguese varieties have chlorotypes A, B, C, and D. The most frequent was the chlorotype A (75%), followed by D (21%). The results obtained reinforced the idea of Western Europe as having been one of the domestication centres for the grapevine, with contributions from the Eastern European gene pool. The observed genetic structure is a starting point from which to clarify the high number of native cultivars found in Portugal, and reinforces their probable origin in the Iberian Peninsula.

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.

The effects of root pruning on the vegetative growth and fruit quality of six-year-old Zhanhuadongzao (Ziziphus jujube Mill.) trees were evaluated. Three root pruning treatments (severe, moderate and light degree) were conducted at the distance of 3, 5 and 7 times trunk diameter from trunk on both inter-row sides of the trees, respectively. The results showed that the severe root pruning decreased the length of primary branch by 27.9% and the number of primary branches by 12.1% in contrast to the control of no root pruning. Compared to the control, both severe and moderate root pruning had no apparent effects on nitrogen, phosphorus and potassium contents of leaves after 35 days, but had significant effects after 161 days. Severe root pruning had larger effectiveness of controlling vegetative growth than the moderate one. By root pruning, the contents of vitamin C and total sugar were increased but the content of cypermethrin was decreased in fruits and no effects were found on total acid content of fruit and yield at harvest. In the rhizosphere soil, root pruning decreased the microbial populations and enzymes activities but increased the concentrations of cypermethrin, available nitrogen, phosphorus and potassium. It is proposed that the removal of root at 3 times trunk diameter distance from trunk was feasible to regulate the vegetative growth and fruit quality of Zhanhuadongzao tree.

A six year old crossbred male dog presented with non-pigmented, pale pink, unhaired, ulcerative tumor of the medial canthus and upper eyelid region. As treatment, surgery was proposed. During the surgery complete excision of the tumor was performed. The extent of skin loss, especially in the upper eyelid required plastic reconstruction by pedicle flap transposition. The soft skin of the cheek was chosen as a graft donor site. The postoperative period proceeded without any complications and ended with successful engraftment. The soft cheek skin did not impede movement of the upper eyelid. Histopathological examination indicated histiocytoma and tumor-free excisional margins were confirmed. There has been no recurrence during the subsequent 12 month period.

The soft palate plays a critical role in the oral and pharyngeal phases of swallowing. Congenitally cleft soft palates (palatoschisis) in calves are rare and pose a serious challenge for surgical correction due to high complication rates. The main obstacles to repairing palate defects are obtaining complicated access to the soft palate, and reducing the tension on the repair so that the sutures hold. A 21 day old female Simmental calf was submitted to our clinic with a history of frequent episodes of coughing and milk dripping from its nostrils after suckling. After clinical examination, a congenital cleft palate was diagnosed. Surgery was performed under general anaesthesia. First, lateral buccotomy was performed to improve the intraoral approach. The palatal defect was repaired using polypropylene mesh and palatal mucosal flap. An oesophageal tube was placed and anchored to the skin using a Chinese finger trap suture technique. Antibiotic treatment was continued through seven days and a transoesophageal feeding tube was fitted at the end of the surgery allowing the calf to be fed with milk during the postoperative period. Postoperatively, the caudal aspect of the repair broke down resulting in persistent mild bilateral nasal discharge. A combination of the two described techniques can be a good option for resolving palatal defects. However, adequate exposure and repair are still difficult to achieve and these approaches often result in serious postoperative complications.

Yields of winter wheat, winter rape and oats were evaluated in the field; the field was divided into the site-specific zones and treated with variable doses of nitrogen fertilizer in years 2004-2006. Measurements of the yields were carried out with a yield monitor placed in a combine harvester. The measured data were processed into the yield maps by means of ArcGIS 9.2 software. Variable application of fertilizer should balance yield potential of the field. Generally, total yield variability on the field after the application of various doses of experimental fertilizer was similar in the years 2004 (11.3%), 2005 (14.7%) and 2006 (11.7%) in comparison with the year 2003 (25.02%). Variable application of nitrogen in the site-specific zones, created on the basis of the yield levels, decreased the yield variability in comparison with the uniform dose. Different doses of nitrogen fertilizer also enabled to increase utilization of production potential of the experimental field.

Astragalus excapus L. and Astragalus austriacus Jacq. are regarded as critically endangered species in Slovakia. They are threatened by environmental impact, natural succession, as well as by human activities. Monitoring them is an important tool in determining their status and in making management decisions for their protection. In this contribution, a summary of the basic terrain endeavours, current status, locality and species description, habitat preferences, possible threats, current protection, and management activities are presented.

Estimates of the effects influencing the economics of pig production are of primary importance for breeders. For this purpose, costs, revenues and profitability were determined on the basis of individual parameters of the efficiency of tested pigs and of average commodity prices. The calculation was the result of the efficiency of actual animals and of the average and simulated prices of inputs received by producers in large-scale production operations. 136 animals, 64 of crossbred combinations (LWs × D) × (LW_D × L) and 72 of PN × (LW_D × L) were used. The total cost of 1 pig represented the costs per weaned piglet, feed and other costs; the revenues represented the actual price of a pig at slaughter. Multivariable hierarchical models were constructed to assess the relationships between the following factors: crossbred combination, nutrition and sex, ADG, number of piglets bred, CFM price and carcass price with the outcome variables: costs, revenues and profitability. The results demonstrated that the total cost of fattening pig is considerably influenced by the price of a piglet and feed, not by the price of the carcass and the growth intensity. There was no proof of a relationship between the price of a pig and reproduction and/or the price of feed. Profitability is significantly influenced by the reproduction rate, price of feed, growth intensity and revenues. The results also showed that the intensity of nutrition and the sex considerably influence the total cost of 1 fattened pig, which represents an increase in the total cost by 3.80 € in the application of ad libitum feeding techniques, and 5.39 €/pc in the fattening of barrows. The choice of a suitable combination represents a decrease in the total cost by 1.49% and an increase in revenues by 2.93%. Profitability is significantly associated with the intensity of nutrition, sex and breed. With unrestricted feeding it is reduced by 4.1%, for barrows by 6.6%, and in the use of four-breed combinations of crossbreds it increases by 4.13%.

Information contained in the studbook of the endangered Mallorquí horse was analysed to assess the genetic variability of the breed. Also, the effect of selection for coat colour variation was assessed using a set of 15 microsatellites genotyped on 68 Mallorquí reproductive individuals previously diagnosed for the presence of the chestnut allele on the melanocortin-1 receptor gene. Mean inbreeding for the whole pedigree (310 individuals) was 2.5% while that for the individuals born during the last three years of recording (reference population) was 4.7%. Only 70% of all the founders have genetic representation in the reference population. A comparison of the parameters such as effective number of founders, effective number of ancestors and founder genome equivalents documented that the losses of founder genes occurred very soon after the implementation of conservation strategies. The parameter F_IS computed from genealogical information was positive (0.029) for the whole population and negative (-0.024) for the reference population, thus illustrating the effort of the Mallorquí horse breeders to avoid matings between relatives in later generations. A total of 14 individuals were heterozygotes for the chestnut allele (allele frequency of 10.6%). The rejection for reproduction of the chestnut heterozygote individuals would not affect the overall gene diversity of the population. However, the total allelic richness would decrease both at the within-subpopulation (1.2%) and total contribution level (0.4%). The chestnut heterozygote individuals are a within-breed reservoir of rare alleles that should be preserved to avoid risks for the future viability of the breed.

The paper deals with assessment of biogas yield from mixtures of Reynoutria substrates and livestock manure. The aim was to perform laboratory experiments and suggest suitable fermenter operating conditions (dry matter content, pH, share of substrate components, thermic regime) for metanogenic digestion, then to determine its quality and assess the usability of such produced biogas.

In the Czech Republic, most mycobacterial infections in pigs are caused by the Mycobacterium avium complex (MAC) and potentially pathogenic mycobacteria (PPM) derived from the environment. This study was undertaken after the isolation of PPM from various components of the environment of pig herds between 1996 and 2002 (Matlova et al., Veterinarni Medicina, 48, 2003, 343-357). Between 2003 and 2007, a total of 1114 environmentally-derived samples from 24 farms were examined. After staining according to Ziehl-Neelsen, acid-fast rods were found in 42 (3.8%) samples by direct microscopy, and PPM were isolated from 223 (20.0%) samples by culture. PPM occurred primarily in soil from the paddocks (53.8%), peat (53.2%), bedding (28.4%) and biofilm from the pipeline (21.0%). From MAC, M. avium subsp. hominissuis (MAH) genotype IS901- and IS1245+ was most frequent; M. avium subsp. avium (MAA) genotype IS901+ and IS1245+ and M. intracellulare genotype IS901- and IS1245- were isolated from one (0.4%) and three (1.3%) samples, respectively. The remaining isolates were identified as 19 other mycobacterial species: M. gordonae (n = 8), M. triviale (n = 6), M. flavescens (n = 3), M. nonchromogenicum (n = 3), M. terrae (n = 3), M. xenopi (n = 3), M. fortuitum (n = 2), M. chelonae (n = 2), M. chitae (n = 2), M. abscessus (n = 1), M. gastri (n = 1), M. kumamotonense (n = 1), M. marinum (n = 1), M. parafortuitum (n = 1), M. peregrinum (n = 1), M. porcinum (n = 1), M. scrofulaceum (n = 1), M. smegmatis (n = 1) and M. simiae (n = 1). The remaining 41 isolates of unidentified mycobacterial species did not contain the sequences IS901 and/or IS1245, specific for medically important members of MAC (MAA and MAH); a further 44 isolates were not tested due to their contamination or loss of ability to grow in vitro. A farm where MAH was often detected in the lymph nodes of pigs and in the environment between 1996 and 2002 (Period I), was selected for further investigation between 2003 and 2007 (Period II). A comparison of the findings of mycobacteria on the investigated farm in Period I and in the following Period II showed a significant increase (P < 0.01) in the occurrence of mycobacteria other than MAH, especially in peat samples.

An 8-hour-old Andalusian colt was referred to the Veterinary Teaching Hospital of the University of Cordoba due to weakness, lateral recumbence, diarrhoea and absent sucking reflex. At admission the foal was obnubilated, with cold limbs, pale mucous membranes, tachycardia and diarrhoea. Laboratory results revealed increased hematocrit and total protein concentration, hyperfibrinogenemia, leukopenia, azoetemia, hypertrygliceridemia and a decreased IgG level. A diagnose of failure of passive transfer of immunoglobulins and hyperlipaemia was made. On the third day of hospitalization the foal presented painful and swollen joints, abdominal distension and fever. The ultrasonographic study at this point showed abundant hypoechogenic free fluid content in the peritoneal cavity. Abdominocentesis demonstrated a high peritoneal creatinine:serum creatinine ratio. Culture of the peritoneal fluid was Clostridium spp. positive. Necropsy revealed a tear in the internal umbilical remnant. The final diagnosis was uroperitoneum secondary to rupture of the urachus associated with a Clostridium spp. infection. New emerging aetiologies responsible for uroperitoneum, either by septic urachitis or omphalophlebitis, are emerging. Nonetheless, cases of uroperitoneum induced by Clostridium spp. infection are rare and constitute a new and important finding for equine neonatal medicine. In addition, the hyperlipaemic status in this animal could be a plausible cause leading to septicemia and subsequent uroperitoneum.

Biotic agents driven spruce decline has been observed over several regions in Europe. We studied the spatial pattern of spruce stands mortality due to biotic agents in three spruce dominated regions in Slovakia - the Kysuce, Orava and Low Tatras regions. Regularly reported data on sanitary felling were used for the analysis. Geostatistical techniques and other spatial modelling tools were used to design the zones of biotic hazard for each region. Zone A stands for the totally disintegrated stands with extremely elevated activity of biotic agents. Zone B represents the buffer zone around the zone A. Its width depends on the spreading potential of biotic agents and related stand mortality observed during the last years. Zone C stands for the background areas, with more or less healthy stands. Zone-specific forest protection measures are proposed. Such a system allows for the priority rating of unnatural spruce stand conversion and optimal allocation of forest protection measures.

Bifenazate, a new selective carbazate acaricide, seems to be a very good substitute for propargite to control spider mites (Tetranychus urticae Koch) on hops in the Czech Republic. To investigate the phenomenon of T. urticae resistance to this compound, 20 samples of field populations were taken in several Czech and Moravian hop-growing regions in 2006 and 2007 and subjected to laboratory tests in a Potter tower. Low values of C100 M (100% mortality) in comparison with the supposed registered concentration reveal that bifenazate may become a useful acaricide within the anti-resistant strategy against T. urticae not only in Czech but also in all European hop-growing regions.

Some phenolic acids alkyl esters (methyl, ethyl, propyl, butyl and hexyl) and determine their antioxidant and antimicrobial activities were prepared. The antimicrobial activity against the tested microorganisms Escherichia coli DMF 7503, Bacillus cereus DMF 2001, Listeria monocytogenes DMF 5776, Fusarium culmorum DMF 0103, and Saccharomyces cerevisiae DMF 1017 was investigated and expressed by minimum inhibitory concentration (MIC) in the range of 1.2-20mM. The inhibitory activity of phenolic acids butyl esters was found to be higher than that of methyl esters (MIC below 1.25mM). The antioxidant activity of the selected phenolic acids alkyl esters was investigated by Rancimat method. The esters of 3,4-dihydroxyphenolic acids (protocatechuic and caffeic acids) exhibited higher antioxidant activities in comparison with the respective phenolic acids. The highest antioxidant activity was found in the case of caffeic alkyl esters.

An evaluation of the effects of soil structural heterogeneity on maize (Zea mays L.) root system architecture was carried out on plants grown in boxes containing fine soil and clods. The clods were prepared at two levels of moisture (0.17 and 0.20 g/g) and bulk density (ranges 1.45-1.61 g/ml and 1.63-1.79 g/ml). Soil moisture directly affected the probability of clod penetration by maize roots. Primary roots inside the clods manifested morphological deformations in the form of bends. We observed a significant increase of bends per root length at lower soil moisture (P = 0.02). Root diameter and branching density increased, and lateral root length decreased considerably inside the clods. However, once emerging out of the clods and into free soil, values of all three characteristics remained low. While changes in root diameter were caused mainly by clod moisture (P < 0.05), length of lateral roots was related to bulk density (P < 0.01). Branching density was modified exclusively by an interactive effect of both factors (P < 0.05).

Dynamics of the plant-available potassium (K) has been studied in polyfactorial long-term fertilization experiments since 1980. The fertilization scheme includes 10 combinations of K muriate and farmyard manure application rates (annually 0-230 kg K/ha). At medium treatment (annually 153 kg K/ha), the K balance within an 8-year crop rotation reflected crop specific K application rates with positive annual balances in years of growing silage maize and sugar beet (high K input), and negative in two years of growing alfalfa. Available K clearly corresponded to the dynamics of the K balance, with statistically significant fluctuations from 88 to 149 mg K/kg within one crop rotation cycle. Periodic fluctuations of available K induced by crop rotation were observed also in non-fertilized treatments. The variability of available K contents was influenced primarily by crop plants and experimental unexplained factors; interannual weather fluctuations and field differences were of low significance. In the paper, the importance of interannual K dynamics for the construction of correct long-term time trends is shown and discussed.

Spring wheat var. Vánek was cultivated in pots in a soil naturally contaminated with heavy metals. Experimental plants were treated with three different types of brassinosteroids (BRs; 24-epibrassinolide, 24-epicastasterone and 4154) during two different growth stages 29-31 DC (off shooting) and 59-60 DC (beginning of anthesis). Content of heavy metals (Cu, Cd, Pb and Zn) was determined using AAS method in the plant growth stages 47-49 DC (visible awns), 73-75 DC (30-50% of final grain size) and 90-92 DC (full ripeness). At the stages 47-49 DC and 73-75 DC, the content of the heavy metals was determined in the biomass of whole plants, while at the stage 90-92 DC it was determined separately in straw and grains. After the treatment of plants with BRs a decrease in heavy metals content was observed in the growth stage 73-75 DC (i.e. during the period when the plants are harvested for ensilage purposes. Likewise, a decrease of lead content in the grains by 70-74% in the plants treated at both stages 29-31 DC and 59-60 DC and by 48-70% in the plants of the third group (plants treated at stage 59-60 DC) was determined as compared with the untreated plants.

In 2005, 2006 and 2008 the virulence of wheat leaf rust population was studied on Thatcher near-isogenic lines with Lr1, Lr2a, Lr2b, Lr2c, Lr3a, Lr9, Lr10, Lr13, Lr15, Lr17, Lr19, Lr21, Lr23, Lr24, Lr26 and Lr28. Samples of leaf rust (141 in total) were obtained from different parts of Slovakia. Resistance gene Lr9 was effective to all tested isolates except three isolates from 2008. No virulence was found to Lr19 and genes Lr24 and Lr28 were also highly effective. Low incidence of virulence to Lr2a was observed. Sixty-five winter wheat cultivars registered in Slovakia were tested with seven leaf rust isolates in the greenhouse. Cultivar Bona Dea was the most resistant of all.