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The quality of water has to be controlled and monitored by drinking water suppliers during all stages of the treatment process from the water sources to the end of distribution systems. The research, performed in Czech Republic from 2006 to 2008, deals with the assessment of the affect of water tanks on the quality of water supplied to consumers, specifically from various points of view: microbiological, biological and physic-chemical changes in water accumulation. Also studied was the influence of the air on the quality of accumulated water (secondary contamination), the influence of the structural layout and hydraulic ratios. In the project quick screening methods (paddle testers and BART^TM tests) were applied in the collection of water samples and scrapings from wetted surfaces of water tanks. The results of the contamination degree discovered in the course of the project solution will serve as basic data for a scale that should evaluate the degree of water tank pollution as well as for resulting corrective measures or optimisation of water tank cleaning. The recommendations of limits for a scraping sample are based especially on the microbiological parameters. Secondary air contamination plays an important role in maintains of biologically stable water. Based on the number of microbial contamination discovered water tanks will be categorised and methods of suitable measures to be taken will be stipulated, operation optimisation as well as cleaning (schedule, methods and frequency of cleaning). The water quality in a storage tanks depends on their maintenance, e.g., to prevent the plaster falling on water surface, the use of antifungal surface coatings (prevention the growth of fungi on walls), the use of ceramics surface of reservoir walls, dark conditions (no windows or blue sheets) in all technological units, the prevention of dust fall out, the selection of suitable air condition and special air filters.

Proteolysis is the principal and most complex biochemical event occurring during the maturation of the majority of ripened cheese varieties. In addition to softening the cheese body, proteolysis influences the development of cheese flavour via the formation of amino acid and peptides which make a direct contribution to flavour. Goat, cow and sheep cheeses have been elaborated with raw milk and calf rennet. The extent of proteolysis was monitored over six months of ripening and means of HPLC peptide profile analysis. The influence of season on the changes in hydrophobic and hydrophilic peptides and the HO/HI ratio during the ripening of the cheeses were studied.

A perfect linear correlation was found for methylglyoxal levels in 61 samples of Manuka honey, ranging from 189 to 835 mg/kg, and the corresponding antibacterial activities of the samples, which were between 12.4% and 30.9% equivalent phenol concentration. This clearly underlines that methylglyoxal is the dominant bioactive compound in Manuka honey and above concentrations of around 150 mg/kg directly responsible for the characteristic antibacterial properties of Manuka honey. Methylglyoxal can be a suitable tool for labelling the unique bioactivity of Manuka honey.

Oxidation changes of different types of vegetable oils were studied during microwave heating. Samples of vegetable oils (rapeseed, sunflower, soybean and corn oil), commercially available at the market in the Czech Republic, were heated in a microwave oven. Parameters as peroxide value, conjugated dienes and trienes levels were determined in oil samples before and after heating in the period from 3 to 30 minutes.

Taste is the chemical sensation whose function is not very well known. Recently it was shown that the range of taste is more extensive than the five basic taste sweet, salty, bitter, sour and umami. A metallic taste has been suggested as another basic taste, but its mode of perception is not well understood and has not been really accepted in the taste literature. Ferrous sulphate solutions were presented to the assessors so their sensitivity and best estimate thresholds (BET) were measured. The best estimated threshold range was 0.00049-0.00669 g/l for demineralised water, 0.00079-0.00669 g/l for distilled water and 0.00108-0.00669 g/l for tap water.

Tyramine is the most frequent biogenic amine found in cheese and is also frequently found in other fermented foods and beverages. In total 273 different strains of enterococci from various foodstuffs were studied. A multiplex PCR was designed for the genotypic differentiation of various enterococci strains at species level and for determination of the presence of tyramine producing (tyrdc) gene. E. faecalis and E. faecium were found to be prominent strains in dairy and meat products while, E. faecium and E. mundtii were found to be ruling in case of fruits and vegetables. HPLC analysis was carried out for determination of levels of tyramine. 211 i.e. 86.8% of samples were containing about 1000-1500 mg/l of tyramine, while 10 i.e. 4.1% were found to have tyramine in the range 100-500 mg/l. Negative samples showed 0 mg/l of tyramine.

In this work the Cd, Cu and Zn accumulation in potatoes, their influence on starch, water-soluble (WSS) and water-insoluble saccharide (WIS) contents and content of heavy metals in various saccharide fractions of potatoes were determined. The fraction of WSS was isolated by Somogyi method, the WIS fraction was obtained from delipided portion of potatoes. Enhanced pseudototal Cd contents in relationship to limit value 0.7 mg/kg of soil were determined in 13 soil samples (0.72-1.06 mg/kg). Contents of Zn and Cu were lower than their limit values in all observed soil samples. Observed heavy metals have not influence on their accumulation in potatoes, the Cd content in potatoes (0.0015-0.0042 mg/kg f.m.), Cu (0.0590-0.1780 mg/kg f.m.) and Zn contents (0.1887-0.3517 mg/kg f.m.) were also lower than their limit values. The proportion of observed heavy metals in selected saccharide fractions: Cd (mg/kg): 0.017-0.140 (starch), 0.0133-0.2293 (WIS), 0.8711-109.7713 (WSS); Cu (mg/kg): 0.067-1.433 (starch), 0.2844-6.9877 (WIS), 18.0134-1070.5216 (WSS); Zn (mg/kg): 6.667-66.300 (starch), 0.7869-23.3673 (WIS), 101.4842-4020.790 (WSS)

In this work preliminary studies on application of immunochromatographic method to detection of pesticides in food samples, in particular fruit juices, are presented. The aim was to develop immunochromatographic technique on a porous membrane for rapid detection of the pesticides thiabendazole and methiocarb in fruit juices. For detection colloidal carbon conjugated with secondary antibody was used. The tests were evaluated visually. Our results show that in the fruit juices samples examined the detection limit for thiabendazole covered the MRL (maximum residue limit) for food of plant origin established by the legislative and for methiocarb the method has to be further optimised in order to decrease the detection limit below the MRL.

Antioxidant capacity of foods and food supplements based on berries and flowers of medicinal plant elderberry (Sambucus nigra L.) was assessed. Reducing properties of the samples and extracts were evaluated using amperometric detection at working electrode potential -0.8 V after HPLC separation. Moreover, antiradical activity of selected samples was determined by the means of spectrophotometric DPPH radical scavenging method. Electrochemical activity (EA) of fresh juice pressed from elder fruits amounted to 0.71 g AAE/l with anthocyanins as minor contributors (10.2%). Catechins and phenolic acids were the major active groups. During production of elder berry spread, even more than 90% of the EA compounds found in raw elder berry material can be destroyed. Comparable activity may be found also in the products from elder flowers. Although elder blossom syrups possessed similar EA regardless of the technology used (0.033-0.054 g AAE/kg), their chromatographic patterns were often very different. For example, no flavonols were present in the syrups, if traditional preparation comprising 24-h maceration with citric acid was applied. Analyzing the chromatographic patterns, one can distinguish different base materials and technology, which can be used for the authenticity confirmation. Herbal infusions from elder flowers, which contain more flavonols than are in syrups, were 16-27 times richer in EA than drinks prepared from the syrups after recommended dilution. Only the syrup designed for preventing and treating upper-respiratory viral infections showed the EA (0.09 g AAE/kg) comparable to that of herbal infusion (0.13 g AAE/l).

The work was aimed at the growth suppression of cultured listerias strains by cultured lactococci strains or commercial mesophilic cheese cultures during common cultivations in the model UHT milk system (0.5% w/w of milk fat content) at 30°C during 18 h aerobically. Milk was primarily fermented by lactococci at the level of 10⁸ CFU/ml and secondarily contaminated by listerias at the level of 10³ CFU/ml. The most intensive growth suppressions of both Listeria innocua (CCM 5884 or Ln-03) strains were caused by Lactococcus lactis subsp. lactis (LCC 416 or CHCC 2281) strains or DELVO-ADD® 100-X DSF cheese culture; the listerias growth reductions was from the level of 10³ CFU/ml to 10⁰ CFU/ml. Obtained results should be applied to dairy industry provided that HACCP, GHP and GMP systems must be observed.

The effect of egg collection time, genotype and housing system on egg quality characteristics was evaluated in an experiment with laying hens of ISA Brown, Hisex Brown and Moravia housed on litter and in conventional cages. The experiment was conducted from 20 to 64 weeks of age. Eggs were collected and recorded daily at 06:00, 10:00 and 14:00 h. Once every four weeks, two days in row, all eggs laid from each pen or cage at each oviposition time were used for egg quality analyses (total 1 694 eggs). Egg collection time was dependent on genotype. Significantly more eggs were laid at 06:00h by ISA Brown while Moravia laid eggs mainly at 10:00 and 14:00 h. Housing on litter postponed the time of oviposition. The highest egg weight (62.09 g) was recorded in Hisex Brown genotype placed in cages and at 06.00 h. Interactions of all factors were determined also in Haugh units (P ≤ 0.041). Eggshell strength was affected by housing system, genotype and egg collection time (P ≤ 0.049). It was higher in cages than on litter, and lower in the Moravia genotype in comparison with the other two strains.

The analysis comprised purebred Charolais bull calves (CH) and crossbred bull calves born from Hereford (CH × HE) and Simmental (CH × SI) cows. Body weights and daily gains were measured in subsequent periods of the experiment and the post-slaughter evaluation was carried out. Carcass lean weight and dressing percentage were evaluated, as well as the lean content of five prime cuts. Total weight of the five prime cuts was measured and its share in the half-carcass weight was determined. The rib-eye area was also measured. The CH × SI crossbreds reached significantly higher body weights at weaning, 210-day body weights and weights at finishing, as well as significantly higher daily gains in all the periods (P < 0.05, P < 0.01) and were characterized by the heaviest carcasses and most cuts, particularly the round. The crossbreds had the highest total weight of five prime cuts and total lean weight, highest weight of the round and lean weight in the round. Other relationships were found analyzing the share of each cut in the carcass. The share of tenderloin and rump in the carcass of CH × SI was significantly lower compared to the purebred bulls (P < 0.01) and CH × HE (P < 0.05). They also had a significantly lower share of the shoulder, shank and shin, as compared to the other groups, as well as a significantly higher (P < 0.05) share of the neck, as compared to the purebred bulls. The purebred bulls also achieved good results and had the highest share of the prime cuts and the largest mean rib-eye area.

The aim of the paper was to analyse congenital disorders in the Czech cattle population in 1986-2001. The offspring of 474 sires - 215 Czech Simmental, 236 Holstein, and 23 beef - were diagnosed with congenital disorders which were unevenly distributed because only 18 occurred in the progeny of 10 and more sires, in contrast to 88 occurring in the progeny of 1 sire only. Umbilical hernia was the most frequently noted disorder, and 136 sires fathered progeny with limb anomalies. The most frequent gestational accident was schistosomus reflexus, the results suggesting a familial burden. Three sires fathering offspring with the afflicted spinal column and limbs were heterozygous for Complex Vertebral Malformation (CVM) though they had not been reported as such. Foetal defects and stillbirth were quite frequent, and the calves affected were fathered by 56 sires. In rare disorders with a low incidence, an accurate genetic analysis or even simple discrimination between inherited and acquired defects is problematic. It would be our recommendation that those sires with a higher incidence of defects among their offspring should be disqualified from fathering stock bulls, or culled.

Gas chromatography and IDF Standard method (1999) were used to analyze the fatty acid composition of milk fat of mares originating from the following breeds: 10 of Wielkopolska breed, 10 Konik Polski Horses, and 9 Polish Cold-blooded Horses. Eighty-seven mare's milk samples were collected in the years 2000-2002. Unsaturated fatty acids were shown to prevail in the milk fat of mares of Wielkopolska breed (61.32%) and of Konik Polski mares (52.58%) whereas saturated acids prevailed in the milk fat of Cold Blooded mares (54.95%). The study revealed that the fatty acid composition of the investigated groups of mares was breed-specific. Of course, the impact of other uncontrolled factors such as nutrition is not excluded, either.

In an experiment with 45 neonatal male Holstein calves, effects of yeast cultures Yea-Sacc^® 1026 (SC) containing Saccharomyces cerevisiae (strain 1026) and Vitex (KF) containing Kluyveromyces fragilis (strain Jürgensen) on rumen fermentation characteristics were determined. From day 4 to day 56 of age, the calves were allocated to one of the three dietary treatments (Control, SC, and KF) of 15 animals each, placed in individual pens, and fed 4 l of whole milk twice daily and a basal concentrate mixture ad libitum as calf starter feeds. The control treatment was not supplemented with yeast culture. The yeast culture supplements Yea-Sacc^® 1026 and Vitex were top-dressed at 10 g/calf daily on the basal concentrate mixture of treatments SC and KF, respectively. At the end of the experiment (day 56), all calves were slaughtered and the rumen fluid was analysed. The administration of yeast cultures Yea-Sacc^®026 and Vitex to calves did not affect final body weight (BW), BW gain, dry matter intake, feed conversion ratio, ruminal pH, lactic acid concentration and the molar proportion of propionic acid, but it decreased (P < 0.05) the total volatile fatty acid concentration and the molar proportion of butyric acid, and increased (P < 0.05) the molar proportion of acetic acid and the acetate to propionate ratio. In addition, the microbial cellulolytic activity was higher in calves that received both yeast cultures compared to the control treatment. The results of this study suggest that the ruminal fermentation was more stable in calves receiving yeast culture supplements.

Gerbera has gained popularity in the past few years in many countries of the world and it is in great demand in the floral industry as cut flower as well as potted plant due to its beauty, colour, long vase life, and ability to rehydrate after long transportation. The most commercial cultivars are propagated through vegetative means by multiplication through divisions of clumps; however, the multiplication by this method is too slow to be commercially viable. To commercialize this crop and to meet the growing demand for planting material, tissue and organ culture techniques are being used as alternative methods for propagation in many countries. Most of the work has been carried on plant regeneration by adventitious organogenesis from capitulum, shoot tip, leaf, petiole and other parts of the plant. Attention should be paid to improve the technology to achieve 100% success in all species/cultivars to meet growing demands of the growers globally. From the literature, it is evident that gerberas are highly amenable to in vitro studies, as various explants were found to favourably respond to different culture media with different types and concentrations of growth regulators.

More than 1,300 seedlings of European plum originating from crossing combinations with at least one parent showing hypersensitivity resistance against PPV were analyzed for their reaction to artificial inoculation with PPV using the double grafting method with virus infected interstem. It was shown that the hypersensitivity resistance against the virus is a phenotypically quantitative trait. The different kinds of symptoms observed in the test system, which contribute to the hypersensitivity resistance, range from weak necrosis on the leaf blade and on the stem to the death of the whole young shoots. A hypersensitivity index was developed which helps to determine the degree of hypersensitivity resistance of an individual genotype. Its use is strongly recommended as selection tool in breeding for hypersensitivity resistance.

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.

In recent years, the agri-food sector and consumers have begun to look at food not only for basic nutrition, but also for health benefits. The purpose of this study was to investigate the variations in the total antioxidant capacity (TAC) in head cabbage according to the used type of fertilizer. Commercial brands of alternative, organic fertilizers were compared with conventional, mineral fertilizers in culture of head cabbage. There were seven different treatments: Agormin, Agro, farmyard manure, horticultural compost, Dvorecký agroferm, mineral fertilizer, and an unfertilized control. All the treatments assured approximately the same level of nutrients. The level of TAC was measured by the FRAP assay and the effect of storage on TAC was also studied. Average value of TAC in fresh cabbage was 236 ± 60 mg GA/100 g in the year 2005 and 295 ± 27 mg GA/100 g in the year 2006. The TAC value decreased in the course of storage. The average value of TAC after a five-month period of storage was 56 ± 18 mg GA/100 g in the year 2005 and 33 ± 5 mg GA/100 g in the year 2006. This study shows that alternative, organic fertilizers have similar or even better qualities than farmyard manure and that they can contribute to the improvement of nutritional values of vegetable.

In the years 2005, 2006, and 2007 the described pomological characteristics were evaluated and both heritability and correlation coefficients of the determined characteristics of parents and progeny were estimated for the Minaret × Betinka apricot hybrid population. Estimated heritability of fruit weight, over colour and flesh consistency was approximately 0.9. Heritability of flesh colour, fruit attractiveness and fruit flavour ranged from 0.6 to 0.9. The correlations show a strong dependence of the following characteristics of parent varieties and progeny: over colour and fruit attractiveness. Medium strong dependence was determined in the following characteristics: fruit colour and fruit flavour. Weak dependence was found in the case of fruit size.

The elimination of Plum pox virus (PPV) in different stone fruit cultivars was verified by the method of thermotherapy in vivo. Trees of two plum cultivars Čačanská lepotica and Švestka domácí, apricot cultivars Leskora and Velkopavlovická, and peach cultivars Redhaven and Earliglo were used. They were infected artificially with two strains of the virus (PPV-D, PPV-M). Two cycles of thermotherapy in vivo were performed. During the first cycle, 16 trees of plum, apricot and peach were treated for 15 days at 37°C. In the second thermotherapy cycle, 10 trees of individual cultivars of plum, apricot and peach were treated for 22 days at 37°C. In the first thermotherapy (T1), 8 trees out of 16 died; PPV was eliminated in 2 trees of cv. Čačanská lepotica, 1 tree of cv. Švestka domácí and 2 trees of cv. Velkopavlovická. In the second thermotherapy (T2), 1 of 10 treated trees died. The virus was eliminated in 2 trees of cv. Čačanská lepotica, 1 tree of cv. Leskora, 2 trees of cv. Velkopavlovická, and 1 tree of cv. Redhaven. Nine (T1) and seven (T2) months after the thermotherapy, the presence of PPV was detected in 6 out of 11 originally recovered trees using ELISA. Out of 26 trees, 4 trees remained recovered: 2 plum trees and 2 apricot trees. One of these trees, apricot cv. Leskora was originally infected with PPV-M strain, whereas the other three with PPV-D strain. None of the 10 peach trees was treated successfully.

: Stamen morphologies of six cornelian cherry cultivars (Degirmendere, Erkenci Degirmendere, İri Bardak, Yuvarlak Bardak, Uzun Memeli, and Bugur) (Cornus mas L.) were evaluated using scanning electron, light and stereo microscopes. Flowers of cornelian cherry cultivars generally had four stamens, but a few of them had three or five stamens. Abnormal and normal stamens were found together in the cultivars examined. Percentages of abnormal stamens among the cultivars ranged from 12% to 22%. Various types of stamen abnormalities were identified in the cultivars such as variations in filament length, abnormalities in anther structure, fusion of stamen to other floral organs. Pollen grain numbers per anther varied between 1,380 and 4,240 among the cultivars. Abnormal anther surface morphology in the cultivars consisted of uneven and swollen epidermal cells. Anther dimensions varied between 624.00 and 1,001.25 μm in length and 460.50 and 745.50 μm in width. Anthers of all the cultivars had subprolate and prolate type of shapes.

Koch method of ornamental trees evaluation is based on interest paid on costs invested in tree-growing up to their maturity stage minus deductions for age, defects and damage. The aim of this paper is to apply the above mentioned method in the economic conditions of the Czech Republic. The paper presents essential economic data generated in accordance with the technological model of tree growing at a permanent site. We also describe the mechanism of the so-called base tree price calculation as a basis for the subtraction of deductions derived from its current condition. The calculated base tree prices are illustratively compared to prices based on the to-date applied calculating techniques and the relevant regulation. We also refer to the method of base price adjustment based on the criterion of landscape tree value. The mechanism of price calculation applied for Koch method testing included two modifications. The first relates to due consideration of growth qualities when calculating development care costs; the other introduces landscaping value indicator as the only base price adjustment to achieve the resulting price, corresponding with the current tree condition.

The paper is the 6^th report on the production potential and stability of mixed forest stands in uplands. A mixed beech/larch stand that was established by natural regeneration in 1934 to 1942 is assessed. The stand is situated at an altitude of 460 m above sea level. It has been left to its natural development since 1961. At that time, the stand was characterized as an individually mixed, diameter- and height-differentiated 25-year pole-stage stand. The proportion of larch and beech amounted to 40% and 17%, respectively. Hornbeam (25%), oak (11%) and to a lesser extent birch (5%) and spruce (3%) also occurred in the stand. In the course of 42 years, the proportion of larch in this stand without planned thinning measures decreased to 35%. On the other hand, the proportion of beech increased to 39%. During all 5-year inventories, the stand could be characterized as a stabilized one with high production potential. Its initial growing stock 63 m³/ha at an age of 25 years increased to 497 m³/ha at an age of 67 years in 2003. At present, current volume increment amounts to 9.8 to 12.5 m³/ha/year.

The Bohemian-Moravian Upland shows a large-scale decline and dieback of Norway spruce up to the forest altitudinal vegetation zone (FAVZ) 5. This phenomenon has been observed in the last 7 years and its progress is rapid. Healthy, declining and standing dry trees of equal height were mutually compared in nine forest stands (aged 3-73 years). These parameters were measured: increment dynamics, root system architecture, biomass, fine root vitality and mycorrhiza, infestation by biotic and abiotic agents. Analyses were done for 414 trees, soil characteristics and weather course data covered the period 1961-2004. Warming and precipitation deficit are the predisposition factors. Weakened trees are aggressively infested by the honey fungus (Armillaria mellea), and they die from root rots. In this paper we describe the mechanism of damage to and dieback of the spruce trees concerned.

The paper characterizes the natural conditions and current state of floodplain forests in the area of Litovelské Pomoraví and proposes the protective management of the area in accordance with the European Natura 2000 system. The paper describes the geographical location and the natural conditions of the area of interest (climate, geology, geomorphology, hydrology and flood regime, soils, and vegetation). Six groups of geobiocene types were identified, classified and described in detail. Assessment of the ecological stability of the forest stand was carried out using biogeographical differentiation of the landscape and the outline of the forest ecosystem management is drawn based on the differentiation of the protected landscape area into zones with various levels of protection.

The main task of the study was to investigate the growth conditions of silver fir natural regeneration in the Karkonosze Mts. (Poland). The paper examines the quantity and quality of light reaching the forest floor in stands of different canopies. The aim of the study was also to define the optimal site conditions for silver fir planting under stand canopy. Data on the natural regeneration and stand structure of each investigated stand were collected on circular plots in a grid of 15 × 15 m in 1999 and 2000. Biometric measurements of fir plants planted under various stand canopies were done three times (May 1999, autumn 2000 and 2001). It was found that the fir was not a dominant tree in all size classes from seedlings to saplings. Seedlings (both phases) of spruce, beech, sycamore and rowan occurred in all studied stands. The optimal conditions for fir development were found under larch canopy. That was demonstrated by the highest increment of height, diameter and offshoots. The worst conditions for fir growth were under beech and spruce canopy, which was indicated by the lowest diameter and height. The highest PAR was recorded under pine canopy, whereas the lowest one under beech canopy. Beech stand induced a lower R:FR ratio than the other tree species both on sunny and cloudy days. The highest R:FR ratio was found under the canopy of larch and pine stands.

Soil properties of forest ecosystems depend on synergy of both parent material and organisms living in the soil, i.e. tree species communities including related plant and animal species. However these soils were not left intact being converted into agricultural land; addition of both nutrients and organic matter and cultivation using tillage led to increased fertility of topsoil. Even long-term afforested soils show differences which are considered as legacy of past agriculture. The change remains detectable for decades; though the altered properties are obvious especially couple of years after planting (approximately 10 years). We found increased concentrations of nutrients (P, K, Ca, and Mg) and subsequent increased base saturation (V %) in former tilled soil only. Moreover, there were no differences between topsoil and subsoil properties (69% and 72%, respectively). In addition to significantly lower saturation (both 0-10 cm and 11-30 cm layers) detected in the long-term-forest and 50-year-afforested (both covered with Norway spruce stands) soils in comparison with adjacent 10-year-old afforestations, there was found significantly lower base saturation in topsoil horizons compared to underlying ones.