Fulltext search in archive

An isolate of Grapevine virus A (GVA) from the Czech Republic was obtained from the grapevine cultivar Müller Thurgau. Symptoms of GVA - Kober stem grooving disease were not observed in the infected grapevines (which had been grafted onto Kober 5BB rootstock). A partial genomic sequence of the GVA isolate, 1523 nucleotides long, was obtained. The sequence completely covers the genes for both a movement and a coat protein. Compared to the GVA sequences available in databases, the nucleotide identity reached 84%. The amino acid identity in the movement protein reached 88%, and 98% in the coat protein.

Yogurt was prepared from goat's milk, supplemented with aronia juice and blueberry juice. The dynamics of acidification, number of lactic acid bacteria, and fatty acids composition were investigated. Yogurt from goat's milk, supplemented with aronia juice and blueberry juice, coagulated at a lower acidity and faster than natural yogurt. The numbers of lactic acid bacteria in supplemented yogurts were higher compared to control samples. The addition of aronia and blueberry juices increased the amount of unsaturated fatty acids in yogurt by 6.9% and 8.5%, respectively. Polyunsaturated fatty acids increased by 11.2% in yogurt with aronia juice in comparison with natural yogurt.

Dynamics of sperm motility (sperm velocity, percentage of motility and flagellar beat frequency) and monthly variations of semen characteristics (semen volume and osmolality and sperm concentration and motility) were studied in Perca fluviatilis. This study showed that sperm velocity, percentage of motility and flagellar beat frequency significantly and rapidly decreased after the activation of sperm motility. Twelve spermiating males were randomly selected and electronically tagged to study monthly variations of semen characteristics. The semen was collected 4 times (29^th November 2005, 10^th January 2006, 21^st February 2006, and 7^th April 2006). Semen volume did not change significantly from November to February, but it significantly increased in April. Sperm concentration was higher in November and January than in February and April. The highest and the lowest osmolality of semen was observed in January and April while it decreased in February and April. At 15 s post activation, the lowest percentage of motile spermatozoa was observed in November. The semen samples collected in April showed the lowest motility of spermatozoa (24.3%) at 30 s post activation. But the percentage of motile spermatozoa collected from November to February showed more than 65% motility at 30 s post activation. At the end of motility period (60 s post activation), no motile spermatozoa were observed in April, and the highest motility was in November. Sperm velocity did not show any significant differences at 15 s post activation. The lowest sperm velocity was observed in April at 30 s post activation.

Many chemical changes in beer aroma occur during storage (aging), and monitoring these changes could give guidelines to the brewers how to manage and control the brewing process to obtain the final product with a high stability in flavour after packaging. In this regard, our laboratory aimed at a research into the application of an electronic nose in order to get the fingerprint of the change of non alcoholic beer aroma during aging. Th discriminatory power of the sensor array of this system was evaluated. Principal Component Analysis (PCA) and Soft Independent Modelling of Class Analogy (SIMCA) techniques were used for this purpose. The results obtained can direct us to performing other parts of our project. Considering the discriminatory power of the sensor array used, we can develop the application of a specific electronic nose system by picking up the most effective sensors or ignoring the redundant sensors.

The present study was undertaken to quantify changes in the status of soil nutrients, their depletion and build-up after continuous long intensive cropping for last 36 years in a permanent manorial trial which has been in progress since 1972 in an alfisol of western Himalayas. The rotation was maize-wheat which included various combinations of N, P, K, Zn and FYM (farmyard manure). Continuous cultivation influenced pH, OC (organic carbon), available N (nitrogen), P (phosphorus) and K (potassium). An increase in the status of organic carbon was observed in 100% NPK + FYM treatments for more than three decades from initial value of 7.9 to 12.0 g/kg. The use of either FYM or lime alongwith 100% NPK sustained crop productivity or improved nutrient status. However, imbalanced use of nutrients i.e. NP or N alone is adversely affecting the fertility of soil by aggravating the problem of soil acidity. Application of S free P fertilizer DAP (diammonium phosphate) drastically reduced the yield of both the crops. Thus, continuous use of balanced fertilizers is necessary for sustaining soil fertility and productivity of crops.

The aim of our study was to determine the prevalence of hepatitis E virus (HEV) in domestic pigs and to investigate the genetic divergence of swine HEV in the Czech Republic. To this end, a one-step real time RT-PCR assay was introduced as a screening method while nested RT-PCR was used as an additional method to obtain specific sequences from the HEV genome and thus to perform sequence analysis. A total of 63 piglets originating from 14 farms were examined. Bile and intestinal contents were collected from each animal. At least one HEV RNA positive piglet was found in ten (71.4%) of the monitored farms. HEV RNA was most frequently detected in bile samples (34.9%) compared to intestinal content samples (22.2%). In nine piglets (14.3%), both biological samples were HEV RNA-positive. Based on these results sequence and phylogenetic analysis of one randomly selected HEV isolate originating from each HEV RNA-positive farm was performed. Analysis of 287 bp PCR products of the ORF1 gene showed that all the studied HEV isolates could be classified into genotype 3 and subgenotypes 3f and 3g. The failure to find any 100% homology between our isolates and HEV isolates deposited in the GenBank confirms the significant variability within the HEV genome.

In human medicine, the association between intussusceptions and inflammatory bowel disease is well known, even if referred to only in case reports or a small series of patients. The exact cause of intussusceptions, in general, is unknown; however, any lesion in the bowel wall or irritant in the lumen that alters the normal peristaltic pattern may initiate invagination. In Crohn's disease the lead point may be dysrhytmic contractions secondary to the on-going inflammatory process of a thickened, inflamed segment of bowel wall. In veterinary medicine, the information available related to the association of intussusceptions and inflammatory bowel disease is limited. The present study is the first reported case of a dog in which ileocolic intussusception and histiocytic ulcerative colitis appear to be associated. Moreover, this is also the first description of the involvement of the caecum in canine histiocytic ulcerative colitis. Herein, we document a condition previously reported in humans with inflammatory bowel disease, and we believe that this work contributes to identifying the similarities between human and canine inflammatory bowel disease.

The aim of the paper was to evaluate the efficiency of winter rape growing which is based on the calculations and an analysis of production and economic indicators in the given branch. The development analysis of yields per hectare, costs, revenues and production profitability was carried out over the years 2003-2009 in the Agro Žlunice and it was compared with the results of the Czech Republic as a whole. In the enterprise, it deals with the traditional growing technology with a higher intensity of the intensification factors inputs in growing. Yields per hectare in the farm reached very favourable values which supported the stable position of the enterprise in the market with this agricultural commodity. It is possible to see a competitive advantage in the level of the per hectare yields. An average yield in the joint-stock company from 2003 to 2009 was 4.34 t/ha and an average yield in the CR over the last seven years was 2.9 t/ha. The enterprise's yield is by 1.44 t per ha higher compared to the average yields in the CR. In comparison of the average costs per hectare over the evaluated period in the enterprise and in the CR - in the enterprise, the costs were by 2.71% higher comapred to the CR (the enterprise 21 991 CZK/ha, the CR 21 394 CZK/ha). However, the enterprise Agro Žlunice, a.s. reached in comparison of the cost per 1 tonne of production by 31.31% lower costs than is the CR average. The amount of expenses incurred was compensated by high yields per hectare which the enterprise reached and thereby it improved the profitability of growing of this crop-plant. The highest share in the total costs belonged to direct material costs. The share of material costs in the enterprise over 7 years was 55.28%. Among the direct material costs, there are mainly seeds, fertilizers and chemical prophylactics. From the indicators of production profitability, there are expressed the profit achieved per 1 t of seedsfrom 1 ha of the area under crop and cost profitability. The profitability indicators considerably fluctuate during the evaluated years in the monitored enterprise and in the CR in dependence on the fluctuation of the seed price.

Globalisation is at the beginning of the new century a double-edged weapon: a strong driving force of economic growth, the development of new technologies and the growth of the level of living in the poor as well as rich countries, but also a controversory process which damages national sovereignty, undermines the local culture and traditions and presents a threat of the economic and social non-stability. The key question of the 21^st century then is, whether the states will be able to keep the process under control or whether they will become its victims.

Low molecular weight proteins were extracted and isolated from rapeseed and analysed using the HPLC-DAD method. The separation of proteins and phenolic compounds was done on the reversed phase C₁₈ column with a gradient of acetonitrile in water. The chromatogram was characterised by two peaks of low molecular weight proteins with the retention times of 19.92 and 23.24 min. Additional three main peaks of phenolic constituents were recorded on the chromatogram. One of them with maximum of UV spectrum at 328 nm was identified as sinapic acid derivatives.

The efficiency of border rows to prevent the adventitious presence of GM maize in non-GM maize plots was evaluated as well as the effect of the MON 810 maize of the yield and self-protection against the European corn borer. The GM maize MON 810 event was drilled at 3 locations over the Slovakia and the grain samples were collected from the neighbouring conventional maize fields. The data obtained by Real-Time PCR indicate that coexistence between GM and conventional maize is feasible and the isolation distance of 200 m (respectively 100 border rows of conventional maize) separates GM maize from the conventional one more than sufficiently. The effective isolation distance is 3-4 times greater than the actually needed. The MON 810 revealed also the highest yield and the best self-protection against European corn borer in both growing seasons with different climatic conditions.

The production technology of high-quality vodka used in Russia involves filtration through activated charcoal. To approach the quality of renowned Russian vodka, one prominent Czech spirit-producing company installed on its production premises a filtration device including a charcoal column, and launched test runs during which different filtration conditions were tested. Samples collected during the test runs were analysed by GC-FID and GC-MS with the aim to compare their composition; sensory analysis was an integral part of the evaluation. The results documented a positive effect of charcoal filtration on the quality of produced vodka, which was not reduced when higher flow rates were applied.

The adverse effect of the application of phosphorus (P) on arsenic (As) adsorption by soils can result in increasing mobility and availability of As. However, in different soils, P might influence As adsorption differently. In this study, the arsenate [As^(V)] adsorption capacities of six soils with different properties and the effects of P application were studied. The results indicated that the adsorbed As^(V) contents all increased as a function of the As^(V) content in equilibrium. When analysed using the Langmuir and Freundlich equations, the maximum As^(V) adsorption capacity of 0.72 mg/g was found for an Alumi-Plinthic Acrisol, while the minimum capacity of 0.09 mg/g was observed for an Epigleyic Cambisol. The adverse effects of P application on As^(V) adsorption by the six soils were observed to be variable. When the P/As molar ratio in a culture experiment was increased from 0 to 10, the maximal and minimal decreases in the As^(V) adsorption capacity of 0.086 and 0.014 mg/g were found in the Alumi-Plinthic Acrisol and Epigleyic Cambisol, respectively. P was relatively more effective in competing for adsorption sites with As^(V) in the Alumi-Plinthic Acrisol and Luvi-Endogleyic Phaeozem due to their higher A/P values (decrease in adsorbedAs/added P) of 1.143 and 1.135, respectively. These results will help decrease the environmental risk of some As-contaminated agricultural soils through the controlled application of P.

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.

The study was conducted to investigate the presence of Campylobacter spp. in meat sold to consumers at a retail market in Poland. Antimicrobial resistance and the presence of putative virulence genes of the isolates were also examined. A total of 558 meat samples, including beef (n = 105), pork (n = 85), and poultry (n = 368) were collected over an almost three year study period. It was found that 321 samples, all of them originating from poultry, were contaminated with Campylobacter spp. Most of the obtained isolates were classified as C. coli (189 strains, 58.9%), whereas C. jejuni was identified in 132 (41.1%) samples. All Campylobacter strains were susceptible to gentamicin and all but one C. coli isolate to erythromycin. On the other hand, the highest level of resistance among Campylobacter tested was to ciprofloxacin (91% for C. jejuni and 86.1% for C. coli) and nalidixic acid (89.3% for C. jejuni and 85% for C. coli). Furthermore, resistance to two or more classes of antibiotics was found in the majority (60.9%) of Campylobacter spp. and among them one C. coli strain showed resistance to four different classes of antimicrobials. Identification of virulence genes in the isolated Campylobacter showed that all of them had the flaA and cadF genes. The iam marker was found more often in C. coli strains (88.8%) compared to C. jejuni isolates (53.8%). On the other hand, the virB11 gene was identified only in 4.2% of C. coli and in 6.1% of C. jejuni strains, respectively. Furthermore, the prevalence of the cdtA, cdtB, and cdtC genes among C. jejuni strains was 97.7%, 93.2%, 96.2%, respectively, and was significantly higher than for C. coli regarding the cdtC (66.7%) gene. The obtained results showed that the presence of Campylobacter in retail meat may represent a threat to public health.

This paper presents research results of the performance of HSM-904 grapple skidder using a full tree harvesting method in a non-native aspen Populus deltoides plantation in even terrain conditions in Shafaroud, Northern Iran. Patch cutting as a silvicultural method was used in the plantation (2,000 ha). To evaluate the newly introduced machine to a ground skidding system in the aspen plantation and the possibility to increase the production rate, an empirical time study was conducted. The elements of the skidding work phase were identified and 58 cycles were recorded for the study. The models for effective time consumption, total productivity and work phase models are calculated. The average load per cycle was 2.2 m³, the average one-way skidding distance was 253 m. The average travel speed of unloaded skidder was 5.53 km.h^-1 and the average speed of loaded skidder was lower than the speed of the unloaded one by 2.94 km.h^-1. The average output in the study was 7.1 m³ per effective hour and the unit cost was 13.9 USD.m^-3.

The notion of international relationships is supplemented by other phenomena during the last time. One of them is globalisation, called on by technological, social and cultural changes, which have shortened the economic distance among countries. The improvement of transport and communication technologies has decreased transport costs of goods, people and information. Traditional governmental policies limiting the cross-border transactions were liberalised or removed what in consequence brought about the growth of international trade and foreign direct investments (FDI). Globalisation changes the properties of the world economy and influences the core of the successful economic approaches to development, what increases the need to secure the sustainability of economic development.

The reaction of five apple cultivars to olive wilt caused byVerticillium dahliae Kleb was evaluated. Five apple cultivars (Royal Gala, Delicious Anabri, Double Red, Golden Delicious, Granny Smith) and one olive cultivar (Nabali Mohassan) were inoculated with V. dahliae and grown under partially controlled greenhouse conditions. Typical symptoms of the disease were developed on the inoculated olive seedlings. However, all tested apple cultivars did not show the typical symptoms of Verticillium wilt except cv. Delicious Anbari, which showed 8.31% disease severity. The average percentage of disease severity was 61.2% in Nabali Mohassan. The pathogen was positively re-isolated from the inoculated seedlings of cvs Nabali Mohassan and Delicious Anbari after 12 months from the inoculation date. Results indicate that an apple plantation to replace dead or severely diseased olive trees infested with Verticillium wilt is an appropriate low-cost and environmentally sound IPM alternative approach to control Verticillium wilt.

Combined culture of lactic acid bacteria (Lactobacillus brevis, L. plantarum i L. sanfranciscencis) and baker's yeasts was used in order to reduce immunoreactivity of gluten from wheat. Flour and dough samples were analysed in terms of lactic acid fermentation and thermal processing. Their immunoreactivity was determined with ELISA method using both anti-gliadin antibodies from patients suffering from coeliac disease and rabbit anti-QQQPP peptide (main epitope of flour allergen) antibodies. Also, immunoreactivity was measured in the final products after simulated digestion. The obtained total effectiveness of the fermentation and digestion processes amounted to less than 30% relative to immunoreactivity of human anti-gliadin antibodies and less than 10% relative to immunoreactivity of anti-QQQPP peptide antibodies as compared to the baking made with non-fermented flour.

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.

An incubation study was carried out to investigate the influence of nitrogen rates to determine optimum C/N ratio under various moisture levels for straw decomposition and sequester carbon (C) in the soil. The aim was to observe straw carbon mineralization through measuring the amount of CO₂ evolution. A clay loam topsoil mixed with maize straw was supplied with four nitrogen rates (0.04, 0.08, 0.16, 0.32 g N/kg) using (NH₄)₂SO₄ to adjust C/N ratios at 82, 42, 20, and 10. Soil moisture was maintained at 55%, 70%, 85%, and 100% of field capacity incubated at 25°C for 53 days. The experiment was set up with 16 treatments arranged in complete randomized design. Results showed that mixing of straw with soil increased 50% cumulative CO₂-C compared to controls. Averagely, about 44% of added maize straw C was mineralized to CO₂-C. Straw addition along with nitrogen and moisture had significant relationships (P < 0.05) to cumulative CO₂-C, soil organic C and microbial biomass C. There was a highly significant relationship (R² = 0.99) between CO₂-C emission and incubation time.

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.

Claw lesions and lameness in sows are an important welfare concern as well as a cause of considerable economic loss. These problems are more common in group housing than in individual housing systems. Given that group housing for gestating sows will become mandatory in the EU from 2013 onwards, the aim of the present study was: (1) to determine the prevalence of lameness and claw lesions in sows housed in groups during gestation, and (2) to analyze whether the type of group housing system and sow-related factors were associated with lameness and claw lesions. Eight Belgian pig herds with group housing of gestating sows were selected. Four herds used pens with electronic sow feeders (dynamic groups), the other four herds kept their sows in free access stalls (static groups). All sows were visually examined for lameness at the end of gestation. Claw lesions were scored after parturition. Information about feed, housing conditions and culling (strategy) was collected, as well as information about parity and breed. Of all 421 assessed sows, on average 9.7% (min. 2.4%, max. 23.1%) were lame. Almost 99% of the sows had one or more claw lesion with overgrowth of heel horn (93%) and cracks in the wall (52%) as the most prevalent lesions. Neither for lameness nor claw lesions was significant differences found between the two types of group housing. Lameness decreased while the mean claw lesion score increased with ageing. These results suggest that lameness can be caused by reasons other than claw lesions, especially in older sows. Although no difference was found between the two types of group housing, a huge variation between herds was observed. Moreover, as the prevalence of lameness and claw lesions in group housing is quite high and group housing will become mandatory in 2013, further investigation on risk factors of locomotor disorders in sows is necessary.

Peat used as a feed supplement for piglets has favourable dietetic qualities; however, its frequent contamination with potentially pathogenic mycobacteria (PPM) has been shown to pose a potential risk to piglet health. The purpose of the present study was to investigate possible ways of devitalising mycobacteria. Examination of 118 samples from various types of commercially available peat (natural peat, packed peat for horticulture and specially processed peat intended for piglet feeding) showed that PPM were present in 84 (71.1%) samples. Mycobacterium avium subsp. hominissuis (82.1%) was the most frequent mycobacterial isolate. In addition, from a natural locality where peat is mined and stored in large piles for up to four months, mycobacteria were detected in peat samples collected from the surface and from up to 25 cm in depth. We used different physical and chemical procedures for peat decontamination (peracetic acid, formaldehyde, steam, and microwave radiation) in attempting to devitalise the mycobacteria in peat. We found that PPM can be reliably devitalised with 1.0% peracetic acid, or 5.0% formaldehyde. However, under field conditions, when using bulk amounts of peat, none of the above procedures were shown to be suitable. Based on these results, the feeding of peat to piglets is confirmed as a high-risk practice.

A five-year-old dog was referred with a five-month history of lethargy, decreased appetite, cough and intermittent forelimb lameness. Radiographs revealed an intra-thoracic lesion and a marked periosteal bone apposition of the second digit on the left forelimb. As it was palisading and circumferential, the latter appeared typical of hypertrophic osteopathy (HO). A grass awn in a sub-lobar ramification of the right caudal bronchus was identified and removed by bronchoscopy. At three months follow-up, the digit appeared clinically normal. On radiographs the periosteal bone reaction had decreased, indicative of resolving hypertrophic osteopathy. Thoracic radiographs showed no abnormalities five months after foreign body removal and the bone lesion on the digit had disappeared. Successful treatment of the pulmonary foreign body abscess led to spontaneous regression of HO and eventually to complete resolution of clinical signs. To the authors' knowledge, this is the first reported case of HO secondary to a bronchial-pulmonary grass an abscess.

Assemblages of earthworms were evaluated in spruce and beech stands in the Kienhaida Nature Reserve (Krušné hory Mts., Czech Republic) and its immediate surroundings, where site conditions were modified by the soil preparation for forest regeneration. The beech stands of the reserve showed low diversity but higher earthworm abundance than did the spruce stands, which in turn showed the lowest Lumbricidae abundance (18 individuals.m^-2). The highest abundance of earthworms (124 individuals.m^-2) was found in the soil of mounds created 30 years prior to sampling from the organic soil of the A_h horizon. The highest species diversity and low abundance were characteristic of areas between the mounds, the soil surface of which was greatly disturbed after removal of the A_h horizon to create those mounds. The degree to which the reforested clear-cuts created due to air pollution were overgrown with weeds contributed positively to the diversity and abundance of Lumbricidae.

The risk rate of sugar beet growing was analyzed by using the algorithm for modelling and generating the random numbers based on the conditions determined in advance and the statistical distribution of sugar beets yield, the total costs, earnings and gross profit. On the bases of results of the analysis of economic risks of sugar beet production in years 1995-2009, it follows that the sugar beet growing in all regions is highly risky in the Czech Republic. The subsidy SAPS and TOP-UP per 1 hectare of sugar beet have a positive impact on its economics though not sufficient enough. In practice, it means that it is highly probable that the break-even point will not be achieved and thereby it is highly probable that the fixed costs are not covered and the update of machines is significantly limited. This happens mainly in the marginal regions. If the agricultural companies count on the separate sugar payment, the sugar beet growing is in all regions of the Czech Republic with acceptable risk.

Spilanthes acmella (Asteraceae) is an endangered ornamental cum medicinal annual herb. This study reports on the effect of two arbuscular mycorrhizal fungi (Glomus mosseae and Acaulospora laevis) applied either alone or in combination on post-transplanting performance of micropropagated S. acmella. Complete plantlets of S. acmella were raised by direct organogenesis from nodal explants on Murashige and Skoog medium supplemented with various cytokinins. S. acmella plantlets responded to all three mycorrhizal treatments in a significantly different way. G. mosseae enhanced the survival rate of S. acmella plantlets to 100%. Plant height, plant spread, number of branches per plant, number of leaves per plant, leaf area, biomass production, and chlorophyll content were significantly higher in AM inoculated plantlets as compared to the uninoculated ones. This clearly demonstrates that AM inoculation improved not only the survival rate of micropropagated plantlets but also their growth and biomass yield.

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 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.