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Results 2971 to 3000 of 5824:

Effects of gap size on natural regeneration and micro-environmental soil conditions in European beech (Fagus sylvatica L.) and Norway spruce (Picea abies (L.) Karst) dominated mixed forestOriginal Paper

Maame Esi Hammond, Radek Pokorný

Plant Soil Environ., 2020, 66(12):607-615 | DOI: 10.17221/397/2020-PSE

The study focused on the effects of gap size on natural regeneration of European beech (Fagus sylvatica L.) and Norway spruce (Picea abies L.) and micro-environmental soil conditions in gaps of different sizes under temperate mixed forest in the Czech Republic. Six gaps comprising two for small (≥ 200 m2), medium (≥ 500 m2) and big (≥ 900 m2) each were selected. Ten circular 1 m2 subsampling plots were established at 2 m intervals along individual North-South-East-West transects, including one at the gap centre. Regeneration was monitored in 2014 and repeatedly in 2019. Soil conditions were only measured in 2019. Gap size was found to be a significant parameter for European beech natural regeneration in 2014. Besides, the quick occupation of European beech in gaps at natural beech zone provoked its prolific regeneration compared to Norway spruce in 2014. However, in 2019 the recent threat of weather variabilities was responsible for the general abysmal growth performance of natural regeneration. Division of gap microsites into different within-gap positions based on prevailing light or shade conditions was helpful in assessing the significant variations of soil conditions within-gap positions and among gap sizes. Soil temperature and moisture significantly influenced the regeneration of European beech and Norway spruce, respectively.

Analysis of chemical and sensory parameters in different kinds of escolar (Lepidocybium flavobrunneum) productsFood Analysis, Food Quality and Nutrition

Hana BUCHTOVÁ, Đani ĐORĐEVIĆ, Stanislav KOČÁREK, Petr CHOMÁT

Czech J. Food Sci., 2015, 33(4):346-353 | DOI: 10.17221/435/2014-CJFS

The chemical composition (nutritional and freshness parameters) and sensory characteristics were evaluated of escolar (Lepidocybium flavobrunneum) defrosted raw fillets and steaks that were marinated differently (pepper, onion, chilly, herbs, knusper, and hot) and packaged in a manner suitable for microwave heating (Darfresh® Simple Steps®). The study was carried out by using 8 skinless fillets of Lepidocybium flavobrunneum. The selected 18 parameters, i.e. dry matter/moisture, crude protein, net protein, collagen, net muscle protein, lipid, ash, saccharide, energy value, pH, water activity, salt content, total volatile basic nitrogen, trimethylamine, free fatty acids, peroxide value, and thiobarbituric acid assay were evaluated. The results indicate that the sample of Chilly marinated steaks was evaluated as the best one (90.29 ± 9.82), however, the samples of Herbs (89.6 ± 13.89) and Knusper (88.64 ± 15.59) marinated steaks also received more than 85 points for the overall impression. Control sample received the smallest number of points (71.7 ± 26.54) for the overall impression.

Variations of soil physicochemical properties and vegetation cover under different altitudinal gradient, western Hyrcanean forest, north of IranOriginal Paper

Hassan Pourbabaei, Ali Salehi, Sepide Sadat Ebrahimi, Fazel Khodaparasrt

J. For. Sci., 2020, 66(4):159-169 | DOI: 10.17221/136/2019-JFS

This study was done to quantify the amount of soil organic matter and to evaluate physicochemical properties and vegetation cover changes along the altitudinal gradient. Nine altitudinal transects were selected from 100 m a.s.l. to 1 700 m a.s.l. Then, 160 circular plots of 1 000 m2 area with a distance of 150 m from each other were studied. Soil texture, bulk density, particle density, soil base saturation, phosphorus and potassium values did not indicate any specific variation pattern. Whereas pH decreased powerfully, the highest and the lowest value of pH was measured at 100 m a.s.l. and 1 700 m a.s.l., respectively. Soil organic carbon content increased significantly with increasing altitude (P ≤ 0.01). Density of trees decreased dramatically from 100 to 900 m a.s.l., whereas this trend was ascending from 1 100 to 1 700 m a.s.l. Density of shrub species increased with increasing altitude along the gradient and the highest value was revealed at 1 300 m a.s.l. The highest percentage of herbaceous species cover was found at a lower altitude and a decreasing trend was found along the altitudinal gradient.

Sperm morphology, ultrastructure, and motility in pikeperch Sander lucioperca (Percidae, Teleostei) associated with various activation mediaOriginal Paper

J. Křišťan, A. Hatef, S.M.H. Alavi, T. Policar

Czech J. Anim. Sci., 2014, 59(1):1-10 | DOI: 10.17221/7188-CJAS

Spermatozoa morphology, ultrastructure, and spermatozoa motility traits were studied in pikeperch (Sander lucioperca) after activation in various media (AM 1 - 45mM NaCl, 5mM KCl, 20mM Tris, pH 8.5; AM 2 - 100mM sucrose, 20mM Tris, pH 8.5; AM 3 - 100mM sucrose, 1mM CaCl2, 20mM Tris, pH 8.5) during a 48-hour storage period. The spermatozoon was acrosomeless and differentiated into a spherical nucleus (head), midpiece, and flagellum. The nucleus length and width measured 1.83 ± 0.03 and 1.63 ± 0.02 mm, respectively. The midpiece was located laterally to the nucleus and possessed proximal and distal centrioles and 2-4 mitochondria. Flagellar length was 33.2 ± 0.90 µm, and a pair of lateral fin-like structures projections was observed. The axoneme consisted of nine peripheral doublet microtubules and a single central pair. After a 24 h storage in all activation media at all sampling times post-activation (15, 45, 90, and 120 s), spermatozoa motility was significantly decreased. Spermatozoa were motile after the 48-hour storage at all sampling times post-activation only in AM 3. After the 48-hour storage, no motile spermatozoa were observed in AM 2 and AM 1 at 90 and 120 s post-activation, respectively. Differences in spermatozoa velocity varied with activation medium during storage. After the 48-hour storage in AM 1 and AM 2, decrease of spermatozoa velocity at 15 s post-activation was observed, while in AM 3, velocity was decreased only after the 48-hour storage. Pikeperch spermatozoa morphology and ultrastructure was found similar to that of most freshwater teleosts, with differences in the arrangement of midpiece, number of mitochondria, and position of centrioles. Viable pikeperch sperm was observed after the 48-hour storage. Motility of spermatozoa was improved by addition of Ca2+ to the activation medium, where higher spermatozoa velocity was observed.

Growth performance, mortality and body and carcass characteristics of rabbit fatteners related to crossbreeding of Mecklenburger Schecke sires with dam line of HYLA rabbitsOriginal Paper

David Zapletal, Petra Jakešová, Eliška Žáková, Vlastimil Šimek, Eva Straková

Czech J. Anim. Sci., 2020, 65(9):337-345 | DOI: 10.17221/192/2020-CJAS

The aim of the study was to evaluate the effect of crossing Mecklenburger Schecke (MS) males with the maternal commercial line of HYLA rabbits on the growth performance, mortality and body and carcass components of fattened rabbits under intensive farming conditions. The control (C) group consisted of albino crossbred rabbits of the HYLA combination AB sires × CD dams. The tested (T) group (MS sires × HYLA CD dams) consisted of rabbit crosses between the MS sires and the same dam line as in the C group. Rabbits of both groups were raised and fattened under identical nutritional and management conditions. The crossing of MS males with the maternal line of HYLA rabbits led to the acceptable growth performance of rabbits in the T group. The higher slaughter weight of rabbits in the T group as compared to rabbits in the C group (P < 0.01) as associated with the higher weight of hot carcass and higher proportions of fore and intermediate parts of carcass (P < 0.01). On the contrary, HYLA rabbits had a higher proportion of the hind part of carcass (P < 0.001); yields of hind leg meat and musculus longissimus thoracis et lumborum were not influenced by the genotype. However, since higher mortality was found in rabbits of the T group during fattening, it is not possible to recommend the MS breed as a common sire line used under conditions of intensive farming at this moment. Regarding the rabbit sex, slaughtered females showed a higher proportion of liver and a lower dressing percentage associated with the worse carcass compactness compared to males.

Determination of leaf characteristics in different medlar genotypes using the ImageJ programOriginal Paper

Sina Cosmulescu, Flavia Scrieciu, Manuela Manda

Hort. Sci. (Prague), 2020, 47(2):117-121 | DOI: 10.17221/97/2019-HORTSCI

The size and shape of leaves can vary significantly between different genotypes within the same species and they implicitly influence plant growth and therefore productivity. The aim of this study was to compare the length, width, and surface area of leaf in nine medlar genotypes (Mespilus germanica L.) through image segmentation procedure using ImageJ software. The data indicate large variations for leaf surface area characteristics from one genotype to another, 2.12 fold for leaf surface area (22.95-48.8 cm2), 1.38 times for leaf length (8.8-12.18 cm) and 1.6 times for leaf width (3.5-5.60 cm). Leaf shape and leaf surface area vary between different genotypes analysed, and the method used can represent a good, non-destructive model of quick and reliable estimation of the medlar leaves surface area. The information obtained can be used in physiology studies, regardless of genetic material.

Effects of Epichloë endophyte and repeated cutting on nutrition compositions of Festuca sinensisOriginal Paper

Weihu Lin, Jianjun Wang, Chong Xu, Dongdong Duan, Wenbo Xu, Pei Tian

Plant Soil Environ., 2020, 66(10):526-532 | DOI: 10.17221/444/2020-PSE

The presence of Epichloë endophyte can promote plant growth and increase the accumulation of host plant nutrients. We determined the dry matter (DM) and important nutritional indicators of E+ (infected by endophyte) and E- (not infected by endophyte) Festuca sinensis under the three-time repeated cutting. The results indicated that the total nitrogen, total phosphorus, crude protein (CP), crude fat (CF), crude ash (CA) contents, and DM of F. sinensis decreased with the repeated cutting increase and reached the minimum after the third time cut. The total organic carbon content of F. sinensis peaked at the second time cut. In addition, the DM of F. sinensis was significant (P < 0.05) positively correlated with its quality CP, CF, and CA contents, and the appropriate repeated cutting times of F. sinensis was 1-2 times. We concluded that the presence of endophyte and proper cutting frequency can increase the quality and biomass of F. sinensis in Western China.

Application of multivariate regression methods to predict sensory quality of red winesFood Analysis, Food Quality and Nutrition

José Luis ALEIXANDRE-TUDÓ, Inmaculada ALVAREZ, Maria José GARCÍA, Victoria LIZAMA, José Luis ALEIXANDRE

Czech J. Food Sci., 2015, 33(3):217-227 | DOI: 10.17221/370/2014-CJFS

Several multivariate methods including partial least squares (PLS) regression, principal component regression (PCR) or multiple linear regression (MLR) have been applied to predict wine quality, based on the definition of chemical and phenolic parameters of grapes and wines harvested at different ripening levels. Three different models including grape phenolic maturity parameters (grape), wine phenolic parameters (wine) and a combination of grape and wine phenolic parameters (grape + wine) were analysed for each of the wine sensory attributes. The grape parameter model has been presented as the best test to predict wine quality based on sensory scores. On the other hand, wine models showed lower accuracy. The combination of grape and wine parameters presented intermediate results showing sometimes good predictability. Moreover, PLS and PCR appeared as more accurate multivariate methods compared to MLR. Although MLR showed higher correlation coefficients, lower RPD values were observed, displaying thus its lower prediction accuracy. Multivariate calibration statistics appeared as a promising tool to predict wine sensory quality in an easy and inexpensive way.

Acceptance of bars with edible insects by a selected group of students from Tri-City, PolandOriginal Paper

Joanna Bartkowicz, Ewa Babicz-Zielińska

Czech J. Food Sci., 2020, 38(3):192-197 | DOI: 10.17221/236/2019-CJFS

Although entomophagy as a diet has been known since the dawn of humanity, it is still considered a novelty to the European market and consumers. This study was performed to evaluate the acceptance of a trend promoted by the FAO diet regarding selected young Polish consumers and it presents the results of a survey conducted among them. The primary goal of this study was to assess the acceptance of new edible insect products with mealworms Tenebrio molitor L. and house crickets Acheta domesticus L. These products were prepared in the form of four different types of bars; one without insects, one with whole mealworms, one with ground mealworms and one with ground crickets. According to consumers, the worst bars were the ones which contained the whole mealworms. Additionally, the main problems with accepting this product were caused by the colour of the ground crickets and visible whole pieces of the insects in the edible bars. The study proved that the acceptance of insect bars as food depends on the tastiness and smell. The acceptance of bars also depends on variants. The basic bar had the highest acceptance rate, while the bar with whole mealworms had the lowest one.

Transient acquired Fanconi syndrome with unusual and rare aetiologies: A case study of two dogsCase Report

JY Park, JH Park, HJ Han, JH Kim

Vet Med - Czech, 2020, 65(1):41-47 | DOI: 10.17221/103/2019-VETMED

The acquired form of Fanconi syndrome is seldom identified in dogs; those cases that have been reported have been secondary to hepatic copper toxicosis, primary hypoparathyroidism, ingestion of chicken jerky treats, exposure to ethylene glycol, or gentamicin toxicity. However, to the best of our knowledge, there have been no reports of acquired Fanconi syndrome secondary to Babesia infection or ingestion of cosmetics in dogs. We here report on two dogs presented with a history of marked polyuria, polydipsia, and lethargy. Laboratory examinations showed glucosuria with normoglycaemia and severe urinary loss of amino acids. One dog was infected with Babesia gibsoni and the other dog had a history of cosmetics ingestion. The first dog received treatment for Babesia infection and the second dog received aggressive care to correct metabolic acidosis, electrolyte imbalances, and other add-on deficiencies. In both dogs, the Fanconi syndrome was successfully managed following the treatment for the underlying causes. In conclusion, both Babesia infection and cosmetics ingestion should be considered as a possible aetiology for transient acquired Fanconi syndrome in canine patients.

Identification of key factors for enhancing competitiveness: an exploratory study of the selected agri-biotech firms of Punjab in IndiaOriginal Paper

Sandeep SINGH, Ravi KIRAN, Dinesh GOYAL

Agric. Econ. - Czech, 2015, 61(4):179-188 | DOI: 10.17221/26/2014-AGRICECON

The present study covers empirical research on the selected Agri-Biotech firms of Punjab. The sample has been chosen from the state of Punjab covering the sectors Food Processing Industry, Fertilizer and Pesticides Industry. On the basis of factor analysis, the study has also identified key factors influencing competitiveness. These are Threat of new competition; Threat of substitute products or services; Bargaining power of suppliers; Intensity of competitive rivalry; Bargaining power of customers; Rivalry among existing firms. The study also tries to evaluate the findings on the basis of the author-factor matrix. The aim is to identify the key factors influencing competiveness. It analyses the difference in competitive factors on the basis of the nature of the industry and on the basis of scale of the firms. Then finally it tries to determine the key competitive factors influencing the market share. The results indicate that the Threat of new competition and Threat of substitutes/services emerge as the important predictors. Intensity of competitive rivalry; Preparedness for Competition; and Bargaining power of suppliers also emerge as significant predictors. These variables explain 79.6% of variation in the model.

A Bayesian analysis of hop price fluctuationsOriginal Paper

Douglas MacKinnon, Martin Pavlovič

Agric. Econ. - Czech, 2020, 66(12):519-526 | DOI: 10.17221/239/2020-AGRICECON

This paper quantifies the correlation between U.S. season average prices for hops with U.S. hop stocks and U.S. hop hectarage. The Hop Equilibrium Ratio, a measure of the supply/demand relationship for U.S. hops, was introduced. Through the Bayesian inference method, the authors used these data to calculate the effect an incremental change to one metric had on the probability of directional changes of future U.S. season average prices (SAP). Between 2010 and 2020, the dominance of proprietary varieties created unprecedented cartel-like powers offering opportunities for supply- and price-management. Research results will enable more accurate forecasting and greater price stability in the hop industry.

Potato nutritional status at the onset of tuberisation - a yield prediction toolOriginal Paper

Karolina Frąckowiak, Jarosław Potarzycki, Witold Grzebisz, Witold Szczepaniak

Plant Soil Environ., 2020, 66(2):86-92 | DOI: 10.17221/533/2019-PSE

A reliable tuber yield prognosis requires a complex statistical analysis of potato nutritional status in the fully developed 4th leaf at the onset of tuberisation. This hypothesis was validated in the series of field experiments conducted in 2006-2008 in Poland. The experimental design was composed of two nitrogen (N) rates (60, 120 kg/ha), two N fertilisers (Urea and Agrotain), two rates of sulfur (0, 50 kg/ha). The marketable tuber yield of cv. Zeus ranged from 31.3 to 59.3 t/ha in 2008 and 2006, respectively. Despite annual variability, the potato presented a good nutritional status. In 2008, the contents of N, Mg, Cu and Zn were about 33% lower as compared to 2006. The stepwise and path analyses indicated N, Mg and Cu as the key yield-limiting nutrients. The diagnosis and recommendation integrated system (DRIS) showed that a slight imbalance of N and Mg did not disturb tuber yield, provided a positive balance of K was maintained. The Mg index, as a result of the DRIS procedure, emerged as the best single predictor of potato yield.

The importance of adverse soil microbiomes in the light of omics: Implications for food safetyReview

Saheed Adekunle Akinola, Olubukola Oluranti Babalola

Plant Soil Environ., 2020, 66(9):421-430 | DOI: 10.17221/118/2020-PSE

One of the most serious threats facing agricultural productivity in the world is unfavourable soil conditions. Several studies have shown that almost half of the world's land-mass is affected by either natural or human-induced pollution. This, therefore, poses a threat to agricultural improvement needed to tackle the problem of a continuous increase in the world population. The emergence of soil extremophiles with plant growth-promoting trait has proven to be a reliable means to quell the threat posed by some factors limiting soil potency. Adopting these organisms as bio-inoculants will easily proffer a solution to both biotic and abiotic soil stress. As such, the natural bio-fertilisers will help to improve the quality of the soil by making it healthy enough to sustain sufficient plant growth. This review gives an overview of the multifarious importance of extremophiles on plants grown under harsh soil conditions, with the multifaceted application of omics as a means to unveil these organisms and their benefits for environmentally sustainable agricultural systems and food safety.

Identification of rare traditional grapevine cultivars using SSR markers and their geographical location within the Czech RepublicOriginal Paper

Kateřina Baránková, Radek Sotolář, Miroslav Baránek

Czech J. Genet. Plant Breed., 2020, 56(2):71-78 | DOI: 10.17221/61/2019-CJGPB

The designation of traditional varieties of grapevine is usually based on verbal information or very dated records. Old rare cultivars found in the Czech Republic were identified by Simple Sequence Repeat (SSR) analysis, a generally accepted method for cultivar identification. These cultivars are primarily maintained in a national collection of genetic resources. Finally a total of 102 candidate genotypes was selected where 49 traditional varieties were identified on the base of nine SSR loci compared with the European Vitis Database. Thirty-six items were registered under the correct designation. The remaining genotypes included four clones, and two genotypes could be described as synonyms. Seven genotypes were found to be incorrectly marked. For three of them, the correct name was found in the database under their SSR profile and four items were considered to be unique as no identical profile was found.

'Mini PS': A new mini melon breeding line exploiting the "Dudaim" variability - Short CommunicationShort Communication

Gabriel Castro, Gorka Perpiñá, Belén Picó, Cristina Esteras

Hort. Sci. (Prague), 2020, 47(4):217-220 | DOI: 10.17221/86/2019-HORTSCI

'Piel de Sapo' is one of the most consumed market class of melons in the Mediterranean area and it represents an important economic crop in Spain. The 'Mini PS' melon breeding line, which bears two main introgressions from the dudaim 'Queen's pocket' melon in the Piel de Sapo genetic background, was evaluated for its fruit quality traits in three environments. Some interesting commercial characteristics were detected, such as a notable decrease in the fruit weight and a rounder shape, compared with Piel de Sapo, while the other quality traits were not altered. Thus, this mini melon line, ideal as a personal melon, may be useful in the development of new melon cultivars.

In situ immobilisation of heavy metals in soils using natural clay mineralsOriginal Paper

Senad Murtić, Emina Sijahović, Hamdija Čivić, Mirza Tvica, Josip Jurković

Plant Soil Environ., 2020, 66(12):632-638 | DOI: 10.17221/371/2020-PSE

This study attempted to evaluate the efficiency of zeolite and pyrophyllite ore materials in reducing the mobility of heavy metals in soil near the lignite mining dumps, and consequently in their availability for plants. Extraction of pseudo-total and available forms of heavy metals from soil samples was performed by using aqua regia and ethylenediaminetetraacetic acid, respectively. Concentrations of heavy metals in soil and plant samples were determined by atomic absorption spectrophotometry. The results of this study illustrate that application of zeolite and pyrophyllite could be a suitable technique to reduce heavy metals availability in soils. Zeolite treatments have been shown to be significantly effective in reducing cadmium (Cd) mobility, as well as pyrophyllite treatments in reducing lead (Pb) mobility in the studied soil, regardless of applied rates. The accumulation of heavy metals in leaves of maize grown on soil plots treated by zeolite and pyrophyllite, was found to be lower compared to the untreated plots. This finding was to be expected, considering the effects of these treatments on heavy metals mobility in the studied soil.

The influence of different intensities of phosphorus fertilizing on available phosphorus contents in soils and uptake by plants

M. Kulhánek, J. Balík, J. Černý, V. Nedvěd, B. Kotková

Plant Soil Environ., 2007, 53(9):382-387 | DOI: 10.17221/2292-PSE

A gradual increase of phosphorus (P) concentrations in combination with organic and mineral fertilizers was applied to clayey soils at six precise experimental field sites with different climatic conditions within the Czech Republic. Soil samples were collected after the harvest of barley. Readily available P concentrations were determined using water and 0.01M CaCl2 extractions, mobile phosphate contents were determined using the extraction procedures Mehlich 3 and Olsen. Furthermore, P uptake by barley plants was assessed. All selected procedures showed that increasing concentrations of applied P increased the mobile and readily available P contents in soils. Phosphorus uptake by barley plants ranged between 9.00 and 14.5 kg/ha and increased P application resulted in increased P concentrations in plants. Statistical analyses were performed using the Spearman test. The closest relationship was obtained for P uptake by plants and the water extraction (r = 0.81). Significant relationships were also obtained for plant uptake and the Mehlich 3 and CaCl2 methods (r = 0.40 and 0.36, respectively). There was no statistical dependence between P uptake and the Olsen method (r = 0.25). Regression analysis was expressed best as linear regression. The closest relationship was found for water extracts and P uptake by plants (with a determination coefficient of 65%). Determination coefficients for P uptake and other methods used were significantly lower (max. 20%).

Variation of the tree form factor and taper in European larch of Polish provenances tested under conditions of the Beskid Sądecki mountain range (southern Poland)

J. Socha, M. Kulej

J. For. Sci., 2007, 53(12):538-547 | DOI: 10.17221/2168-JFS

The genetic variation in 20 provenances of European larch, growing under site conditions of the Beskid Sądecki mountain range (experimental area in Krynica), was investigated during a long-term study carried out within the 1967 Polish Provenance Experiment on Larch. Data consisted of diameter measurements taken outside bark on standing trees of the analyzed provenances. Results showed that there was no distinct variation in the tested larch populations in respect of stem form. Some differences between compared provenances in respect of stem taper and form factor were the result of differences in tree height and diameter.

Dry heat inactivation of Bacillus cereus in rice

Milan Houška, Karel Kýhos, Aleš Landfeld, Jiřina Průchová, Ljuba Schlemmerová, Hana Šmuhařová, Vladimír Špelina, Pavla Novotná

Czech J. Food Sci., 2007, 25(4):208-213 | DOI: 10.17221/692-CJFS

The aim of this work was to validate the method of decontamination of rice at the temperature of 120°C (determined as optimal in previous experiments). Bacillus cereus was selected as the marker micro-organism for the monitoring of decontamination. The spores of Bacillus cereus are moderately heat resistant. In order to show the efficacy of our decontamination process, we artificially contaminated the rice under study with B. cereus. Decontamination was carried out in a homogenising steriliser about 20 h after contamination. The sample was first heated to 90°C and held at this temperature for 70 minutes. Then the temperature was increased to 120°C and held for 3 hours. Five samples were taken for microbiological analyses as follows: before the experiment, on reaching 120°C, and then after 1, 2, and 3 h of decontamination. Decontamination of rice from vegetative forms and spores of B. cereus present at the level of 400 CFU/ml was effected by heating to 120°C and holding for 1 hour.

Laser profilometer testing by laboratory measurements

P. Šařec, O. Šařec, V. Prošek, K. Čížková

Res. Agr. Eng., 2007, 53(1):1-7 | DOI: 10.17221/2134-RAE

Measuring soil surface profile has many purposes in the field of agriculture and landscape management. For example, it concerns quantitative evaluation of work quality of soil cultivation implements, and related assessment of soil surface status prior sowing. For this purpose, a prototype of laser profilometer was produced whose key parts are a laser sensor Banner LT3 fixed together with a control section, a converter etc. on a carriage that travels propelled by an electromotor along an aluminum girder. In 20 mm intervals determined by an optical sensor, the laser sensor measures a distance to a soil surface. The aim of the work is to verify some laser sensor properties such as a linearity of measurement, sensitivity to surface color, and furthermore to establish appropriate window limits of laser sensor measurement.

Model trial investigating retention in selected tissues using broiler chicken fed cadmium and humic acid

I. Herzig, M. Navratilova, P. Suchy, V. Vecerek, J. Totusek

Vet Med - Czech, 2007, 52(4):162-168 | DOI: 10.17221/2031-VETMED

Forty randomly selected chickens were allocated into four groups: K, HA, Cd and Cd + HA. After a 5-day adaptation period, the experiment was initiated. Group K was fed a diet without supplements. Group HA was fed the same diet with a 0.5 g supplement of humic acid per chicken/day. Group Cd was treated with 0.147 mg Cd per chicken/day (0.3 mg of CdCl2 . 5H2O), and Group Cd + HA was given the same treatment as the latter group, with an additional 0.5 g humic acid per chicken/day. The chickens were given the above mentioned treatment daily, for 10 days. Subsequently, they were slaughtered and samples from livers, kidneys and leg muscle (m. flexor perforans et perforatus) were collected and Cd levels determined. The Cd levels detected in Group K are commonly found in market chickens and were assumed to be base background value; these represent 32%, 5.2% and 20% of allowed maximum residual limit (MRL) in kidney, liver and muscle, respectively. The limits are 1.0; 0.5 and 0.05 mg/kg for kidney, liver and muscle, respectively. The ten-day treatment with 0.147 mg Cd/day, i.e. 1.47 mg Cd per 10 days, significantly increased Cd levels in all investigated tissues. Average levels in kidneys, livers and leg muscle were 4.99 ±1.57, 0.558 ± 0.630 and 0.052 ± 0.008 mg Cd/kg, respectively. When cadmium chloride was given together with humic acids, (group Cd + HA), Cd levels decreased in all investigated tissues by 39.6%, 34.2% and 80.8% in kidney, liver and muscle, respectively. The average levels were 3.012 ± 1.33, 0.361 ± 0.367 and < 0.01 mg/kg in kidneys, livers and leg muscle, respectively.

The zinc mobility in three different soils amended by sewage sludge incubated with limestone and lime, and Zn uptake by oats

A. Hanč, P. Tlustoš, J. Száková, J. Balík, D. Pavlíková

Plant Soil Environ., 2002, 48(11):518-524 | DOI: 10.17221/4406-PSE

The effect of sewage sludge application on three soils of different properties (Chernozems - location Suchdol, Luvisols - location Červený Újezd and Cambisols - location Humpolec) was investigated in pot experiment and the accumulation of Zn in above ground biomass of oat as well as availability of Zn released by 0.01 mol/l CaCl2 was evaluated. Stabilised sewage sludge was obtained from three wastewater factories in Czech Republic. Sewage sludge has been preincubated with addition of limestone and lime (7% of Ca w/w of sludge dry solid) in aerobic and anaerobic conditions and tested in pot experiment. The highest Zn mobility reduction was found at Humpolec soil. Sludge amended by lime and limestone reduced available Zn content in this soil (at sludge III by 86% after limestone and by 71% after lime application). Considerable reduction of Zn in plant showed in Humpolec soil treated by sludge with lime (by 20% compared with soil treated by nonincubated sludge - control) and limestone (by 30% after anaerobic incubation compared to control). The positive incubation and treatment effect was not confirmed in the other soils. Available Zn in Humpolec soil showed the strongest correlation among all soils with total Zn content in plant (at aerobic treatment R2 = 0.66 and at anaerobic R2 = 0.83).

Antioxidant and radical scavenging activities of a barley crude extract and its fraction

Ryszard Amarowicz, Zofia Żegarska, Ronald B. Pegg, Magdalena Karamać, Agnieszka Kosińska

Czech J. Food Sci., 2007, 25(2):73-80 | DOI: 10.17221/755-CJFS

Phenolic compounds were extracted from the Candle variety of hull-less waxy barley with 80% (v/v) methanol to yield a crude preparation. Seven fractions (I-VII) were separated from the barley extract so obtained on a Sephadex LH-20 column using methanol as the mobile phase. Nearly 80% of the phenolics extracted from barley were comprised in the first three fractions. The measurements of the antioxidant activity using a β-carotene-linoleate model system, radical scavenging capacity against DPP*, and reducing power based on the reduction of a Fe3+/K3Fe(CN)6 complex to the ferrous state were assessed in the barley crude extract and its fractions. The results indicated that barley possess marked antioxidant and antiradical capacities as compared to other grains such as wheat, rye, and triticale. Furthermore, the methanolic extract of the waxy barley sample and its fractions resembled in the aforementioned activities those from leguminous seeds, rapeseed and pulses. Phenolic constituents contained in barley may have a future role as ingredients in the development of functional foods.

Fungal infection of malt barley kernels in Slovak Republic

Tibor Roháčik, Kamil Hudec

Plant Protect. Sci., 2007, 43(3):86-95 | DOI: 10.17221/2249-PPS

The influence of agro-environmental factors (year, cultivar and climatic factors) on the occurrence of fungi on kernels of malt barley, species spectrum and seedling viability were evaluated during 2004 and 2005. The seeds (asymptomatic, fraction above 2.5 mm) originated from different cultivars and locations of the Slovak Republic. Surface sterilisation of the kernels before isolation of the fungi was the key factor for objective results on the occurrence of Fusarium species. Screening of non-sterilised kernels gave a different spectrum of fungal species and their frequency and may lead to distorted results. The most frequent species isolated from barley kernels were Alternaria spp., Cochliobolus sativus, Epicoccum nigrum, Fusarium spp. and Pyrenophora teres. The results confirmed that agro-environmental factors (mostly year and microclimatic conditions) had a major influence on infection by and population structure of fungi in malt barley kernels. The total sample infection by Fusarium spp. was significantly higher at localities with higher altitude and in 2005. The infection level varied from 0% to 20%, in some localities in 2005 it exceeded 20%. The widest fungal species spectrum was recorded in the locations with high level of kernel infestation. In localities with lower infection, the species spectrum was narrower.

Selenium content in the blood serum and urine of ewes receiving selenium-enriched unicellular alga Chlorella

J. Travnicek, L. Pisek, I. Herzig, J. Doucha, J. Kvicala, V. Kroupova, H. Rodinova

Vet Med - Czech, 2007, 52(1):42-48 | DOI: 10.17221/2007-VETMED

The effect of selenium supplementation in inorganic and organic form was investigated in three five-member groups of ewes and their lambs in the course of 7 months. The basal feed ration contained 55 µg Se, ewes of experimental group E1 received a supplement of 180 µg Se in sodium selenite, and ewes of experimental group E2 were applied a supplement of 180 µg selenium bound in the biomass of the alga Chlorella. Control group C did not receive any selenium. The ewes were in the stage of non pregnant, pregnancy and lactation during the experiment. Average contents of Se in the blood serum of ewes were as follows: E1 114.2 ± 23.6; E2 103.1 ± 20.3; C 68.6 ± 16.8 µg/l (P < 0.001). A decrease in serum Se was recorded in all groups in the last third of pregnancy and in the first week post partum. Average contents of urinary selenium contents were also higher in experimental groups: E1 25.4 ± 13.5; E2 18.7 ± 9.6; C 13.3 ± 4.5 µg/l (P < 0.001). The positive effect of supplementation of Se to ewes was reflected in its higher average concentration in the blood serum of born lambs: E1 48.5 ± 7.3; E2 53.5 ± 3.4; C 30.3 ± 7.4 µg/l (P < 0.05). The effect of selenium bound in Chlorella biomass was higher and persisted until 30 days of lamb age: E1 52.9 ± 3.4; E2 59.0 ± 7.0; C 35.5 ±5.8 µg/l (P < 0.01). The average number of lambs born per ewe was 1.0 in group C and E1, and 1.8 in group E2.

Barley seed sensitivity to water stress at germination stage

V. Hosnedl, H. Honsová

Plant Soil Environ., 2002, 48(7):293-297 | DOI: 10.17221/4370-PSE

Barley seed sensitivity to water and anoxia was tested. Standard germination, mean time of germination (MTG), germination in sand wetted by water to 100% water capacity (anoxia) or by hydrogen peroxide (wet conditions without anoxia), germination in 0.75% hydrogen peroxide and laboratory emergence (15 and 20°C) were evaluated. Barley seed responds sensitively to stress conditions during germination. Significant germination decrease was found in abundance of water. Percentage of reduction depends on the variety and on the year of seed production. Extreme values of water sensitivity are in interval 4-90%. At wetted sand by 0.75%, solution of H2O2 the germination was significantly less reduced. That means that barley seed is very sensitive to oxygen deficiency above all and is less injured by quick imbibition. Heterogeneity in seed vigour was demonstrated in laboratory emergence tests. Quick test of germination in 0.75% hydrogen peroxide deserves attention for its high correlation coefficient with the seed laboratory emergence. The results significantly demonstrate a higher sensitivity of deteriorated seed to germination in abiotic stresses conditions. Variability in speed of germination is increasing, which unfavourably extends the mean time of germination.

Does antioxidant capacity of leaves play a role in growth response to selenium at different sulfur nutritional status?

R. Hajiboland, L. Amjad

Plant Soil Environ., 2007, 53(5):207-215 | DOI: 10.17221/2202-PSE

There are evidences of beneficial effects of selenium (Se) on plant growth. In this work, using alfalfa (Medicago sativa L.) and two varieties of Brassica oleracea L. (cabbage and kohlrabi), the effect of Se addition (10 and 20μM) on growth and concentration of sulfur and Se was investigated in hydroponic experiments. In order to study the involvement of Se-mediated changes in the antioxidant capacity of plants in growth promotion by Se, the activity of antioxidant enzymes including ascorbate peroxidase (APX), catalase (CAT), peroxidase (POD), superoxide dismutase (SOD) and glutathione reductase (GR) and the concentration of H2O2 and glutathione were determined. It was demonstrated that sulfur sufficient cabbage and kohlrabi plants concomitant with growth stimulation in response to Se addition expressed a progressive oxidative stress as judged by a lower activity of antioxidant enzymes and accumulation of oxidants. Results imply that the function of antioxidant system of plants could not explain either the growth stimulatory effect of Se in cabbage and kohlrabi or different response of alfalfa plants to Se supplementation.

Cyclodextrin production from amaranth starch by cyclodextrin glycosyltransferase produced by Paenibacillus macerans CCM 2012

Marian Urban, Miloš Beran, Lubomír Adámek, Josef Drahorád, Petr Molík, Kristina Matušová

Czech J. Food Sci., 2012, 30(1):15-20 | DOI: 10.17221/226/2010-CJFS

Cyclodextrins (CDs) are synthesised by bacterial extracellular enzym cyclodextrin glycosyltransferase (CGTase, E.C. 2.4.1.19) from starch or starch derivatives. The production of α-, β-, and γ-CDs by CGTase from Paenibacillus mace-rans CCM 2012 was studied in regard to the effect of the starch source (amaranth, maize) on the yield of CDs. CGTase was produced by a 3-day sterile cultivation in the laboratory Bench-top fermentor BiostatB under aerobic conditions. CGTase was partially purified by ammonium sulfate precipitation at 60% saturation. Electrophoretic analysis (SDS-PAGE) of the isolated CGTase enzyme was carried out according to the method by Laemmli (1970), the apparent molecular weight was in the range from 105 kDa to 114 kDa. All the commercially important α-, β-, and γ-CDs were detected chromatographically after the hydrolysis of the maize and amaranth (Amaranthus cruentus) starches with the isolated enzyme. The amaranth starch appears to be an excellent substrate for CDs production because of the high dispersibility, high starch-granule susceptibility to amylases, and the exceptionally high amylopectin content.

Efficiency and gases emissions with incineration of composite and one-component biofuel briquettes in room heater

P. Jevič, P. Hutla, J. Malaťák, Z. Šedivá

Res. Agr. Eng., 2007, 53(3):94-102 | DOI: 10.17221/2125-RAE

In accordance with the technical standard ČSN EN 13229 "Inset appliances for heating including open fires fired by solid fuels - Requirements and test methods" was performed the basic assessment of thermal efficiency and emission parameters of prototype of combustion accumulation stove SK-2 with upper after-burning and nominal heat output of 8 kW. Verified gradually were the bio-briquettes of diameter 65 mm from mixture of wheat straw and 20% m/m of brown coal, wheat straw and 5% m/m of brown coal, wheat straw, mixture of wheat straw and 10% m/m of water and molasses solution, Ecobiopal created with the fermented blend of 33% m/m of digested clean water plant sludge and 67% m/m of wood chopped material, blend of wheat straw and 15% m/m of sugar beet pulp, mixture of timothy hay and 25% m/m of brown coal, timothy grass hay, meadow hay, mixture of meadow hay and 25% m/m of brown coal. The lowest CO emissions, when the limit value of 3000 mg/m3N at 13% of O2 has not been exceeded, determined for more strict 1st class and the highest efficiency at nominal heat performance, i.e. higher or equal to 70% (Class I) have been reached by the briquettes produced from mixture of wheat straw and 15% m/m of sugar beet pulp, timothy hay and mixture of meadow hay with addition of 25% m/m of brown coal. Further were measured NOx and HCl emissions. NOx values were significantly lower than limit values determined for similar combustion of solid biofuel. Higher differences of HCl emissions correlate with various Cl content in fuels. Only the wheat straw briquettes with share of 25% m/m of brown coal have exceeded the limit value by 16%. Other fuels have shown considerably lower values. The results have proved better heat-technical and emission parameters of blended briquettes and are significant also for solid biofuels and solid recovered fuels standardization as well as for increasing efficiency method detection and ecological parameters optimization including HCl emissions.

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