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Results 2911 to 2940 of 5716:

The application of RT-PCR assay for the detection of Apple stem pitting virus and Apple stem grooving virus in four apple cultivars

Jiban Kumar Kundu

Plant Protect. Sci., 2002, 38(1):13-17 | DOI: 10.17221/4816-PPS

The reverse transcription polymerace chain reaction (RT-PCR) assay was successfully used for the detection of Apple stem pitting virus (ASPV) and Apple stem grooving virus (ASGV) in four apple cultivars of a 25 years old orchard. These two main pome fruit viruses were detected frequently in all tested apple cultivars. ASGV and ASPV occurred in as many as 16 trees (in the cultivar Spartan) and 13 trees (in the cultivar Idared) out of 20 tested trees, respectively. Mixed infection by ASGV and ASPV was found in all tested cultivars (as many as 9 out of 20 tested trees of the cultivar Spartan).

Effect of selected factors on total carotenoid content in potato tubers (Solanum tuberosum L.)

Z. Kotíková, A. Hejtmánková, J. Lachman, K. Hamouz, E. Trnková, P. Dvořák

Plant Soil Environ., 2007, 53(8):355-360 | DOI: 10.17221/2214-PSE

In the years 2004 and 2005 precise field trials were performed with the aim to evaluate the effect of variety, year of cultivation, N, P, K and Mg fertilization, and the cover with white propylene fibre Paegas-Agro UV 17 on the total carotenoid content (TC) in potato tubers. TC was determined by absorption UV-VIS spectrophotometry and obtained results were statistically evaluated (ANOVA and MANOVA variance analyses, Scheffe's test). Statistically significant differences (P = 0.05) in the ability of varieties to synthesize carotenoids were found (Karin, Agria and Marabel with high TC × Impala and Saturna with low TC) and also the year of cultivation significantly affected TC (5.8 mg/kg fw in 2004, 20.9 mg/kg fw in 2005). The effect of fertilization with N, P, K and Mg on TC in potatoes did not show any significant effect; however significant differences were observed among varieties. The effect of white polypropylene fibre in two early potato varieties (Adora and Impala) during three dates of harvest on TC in potato tubers was not significant. Contrariwise, statistically significant effects on TC were reported in the case of potato tubers maturity, year of cultivation and potato variety.

Results of an orchard trial with new clonal sweet cherry rootstocks established at Holovousy and evaluated in the stage of full cropping

J. Blažková, I. Hlušičková

Hort. Sci. (Prague), 2007, 34(2):54-64 | DOI: 10.17221/1849-HORTSCI

Ten clonal dwarf or semi-dwarf rootstocks were evaluated in a trial that was established in the spring of 1999 at Holovousy. Lapins cv. was used as a scion tester for all these rootstocks; five of them were tested also by Regina cv. Among the new rootstocks G 195/5 was evaluated as the most promising for Lapins cv. The highest rate of mortality and symptoms of poor scion compatibility with Lapins cv. were observed on Weiroot 53 and Weiroot 158. The most vigorous of the tested rootstock was G 497/8 followed by Gisela 7 and Gisela 4. Intermediate vigour was recorded on trees on G 154/7, P-HL-A, Gisela 3 and Tabel Edabriz. The least vigorous were G 195/20, Weiroot 158 and Weiroot 53. The highest accumulated yield per hectare of the Lapins cv. (21.2 tons) was harvested from Gisela 7 rootstock. With Lapins cv. higher yield efficiencies were calculated for P-HL-A, G 195/20 and Tabel Edabriz. In the case of the Regina cv. the highest yield efficiency was on Gisela 7. The mean fruit weight of the Lapins cv. had a span from 8.2 g (Weiroot 53) to 9.7 g (G 195/20). With the Lapins cv. less fruit cracking was observed on fruits from Tabel Edabriz and Gisela 7. Significant differences between tested rootstocks were found also at the time of tree flowering and ripening.

Brachyspira hyodysenteriae: detection, identification and antibiotic susceptibility

M. Novotná, O. Škardová

Vet Med - Czech, 2002, 47(4):104-109 | DOI: 10.17221/5812-VETMED

101 samples of faeces, colonic mucosa and rectal swabs taken from 100 pigs (29 commercial herds) were cultivated on Trypticase Soy Agar with 5% of sheep blood, spectinomycin (200 mg/l), vancomycin (50 mg/l), rifampicin (12.5 mg/l) and colistin (12.5 mg/l). Plates were incubated in an anaerobic container at 37°C for 5-7 days. 25 samples (10 faeces, 15 scrapings of colonic mucosa) were examined by darkfield microscopy for the presence of spirochaetes. In 80 samples (21 faeces, 31 rectal swabs, 28 scrapings of colonic mucosa) from diarrhoeic pigs 44 isolates of spirochaetes were identified by PCR method as Brachyspira hyodysenteriae. In 21 samples (20 rectal swabs, 1 scraping of colonic mucosa) taken from apparently healthy pigs in herds with swine dysentery were isolated weakly haemolytic spirochaetes: B. intermedia in 5 samples and phenotypic group III brachyspirae in 4 samples. Minimal inhibitory concentration (MIC) of tylosin, tiamulin and valnemulin was determined by the agar dilution method. To tylosin 16 out of 17 strains of B. hyodysenteriae were resistant (MIC 64 and 256 µg/l), one strain was susceptible (MIC l µg/ml). To tiamulin 17 out of 19 strains were susceptible (MIC from 0.016 to 0.25 µg/ml), one strain was intermediately susceptible (MIC 2 µg/ml) and one resistant (MIC 32 µg/ml). To valnemulin 17 out of 19 strains were susceptible (MIC from 0.016 to 0.064 µg/ml), one strain was intermediately susceptible (MIC2µg/ml) and one was resistant (MIC 8 µg/ml). Valnemulin resistant strain was also resistant to tiamulin.

Occurrence, biology and harmfulness of Galerucella lineola (F.) (Coleoptera, Chrysomelidae) - Part 1. Last year's (parent) beetles

J. Urban

J. For. Sci., 2007, 53(8):364-380 | DOI: 10.17221/2182-JFS

In Moravia in 1995 to 2006, the abundant occurrence of Galerucella lineola (F.) was used to study its occurrence, biology and harmfulness. An "alder" biological form was studied in Alnus glutinosa and A. incana mainly in Polnička Forest District (Žďár region) and a "willow" form in Salix viminalis, S. triandra and S. caprea in riparian and accompanying stands of the Svitava river near Bílovice nad Svitavou (Brno region). Imagoes leave their sites usually in the 1st half of May. In the course of 2.5 to 3 months, they damage on average 22.6 cm2 leaves of A. glutinosa and S. caprea (of this value, males 3.2 times less than females). Males eat on average 15 times during 24 hours for a period of 3.5 minutes, i.e. in total 52 minutes (3.6% day). Females eat on average 36 times for a period of 7 min, i.e. 252 min (17.5% day). Imagoes copulate on average 10.2 times per day for a period of 67 min. For the whole period of reproduction (about 42 days), they copulate on average 428 times, i.e. for 20 days. Eggs are laid into groups of 3 to 20 (on average 14) pieces. Females lay 457 to 791 (on average 612) eggs, i.e. about 15 eggs per day. Medina collaris (Fall.) (Tachinidae) and Townesilitus fulviceps (Ruthe) (Braconidae) belong, among others, to the enemies of imagoes.

Effect of non-steroidal anti-inflammatory drugs on the blood profile in the green iguana (Iguana iguana)

S. Trnkova, Z. Knotkova, A. Hrda, Z. Knotek

Vet Med - Czech, 2007, 52(11):507-511 | DOI: 10.17221/2061-VETMED

A total of 20 healthy green iguanas (14 males and six females with body weight ranging from 280 to 720 g) were divided into three groups and used for the experiment. Carprofen (2.0 mg/kg, i.m.) was administered to seven iguanas for 10 days, five were treated with meloxicam (0.2 mg/kg, i.m.) for the same period, and eight iguanas received the same volume of saline solution (0.04 ml/kg). All iguanas were blood sampled on Day 1 and 11 to obtain haematological and biochemical parameters. Comparing the values within particular groups, a decrease in haemoglobin concentration and packed cell volume accompanied by an increase in azurophils (P < 0.05) was observed in iguanas treated with carprofen. Decreased values of haemoglobin and packed cell volume were also found in control iguanas (P < 0.05). Increased ALT levels (P < 0.01) were found in all three groups of iguanas. A decrease in the concentration of Ca (P < 0.01) was observed both in meloxicam-treated iguanas and in the control ones. Mean ALT values of carprofen-treated iguanas (2.42 ± 0.52 μkat/l) were considerably higher (P < 0.01) than those in iguanas treated with meloxicam (0.49 ± 0.18 μkat/l) or saline (0.43 ± 0.13 μkat/l). Repeated doses of carprofen induced higher levels of AST (0.82 ± 0.26 μkat/l) compared with saline (P < 0.01, 0.31 ± 0.16 μkat/l) or meloxicam (P < 0.05, 0.38 ± 0.16 μkat/l). All blood parameters of green iguanas following the 10-day intramuscular administration of both carprofen and meloxicam were within the physiological reference values of this species.within the physiological reference values of this species.

Effects of seed origin, growing medium and mini-plug density on early growth and quality of black locust (Robinia pseudoacacia [L.]) seedlings

O. Dini-Papanastasi, P. Kostopoulou, K. Radoglou

J. For. Sci., 2012, 58(1):8-20 | DOI: 10.17221/46/2011-JFS

The objective of this study was to identify optimal growing conditions for the production of high-quality mini-plug seedlings of black locust (Robinia pseudoacacia [L.].). Two seed origins (Greek and Hungarian), two growing media (enriched peat and stabilized medium) and four mini-plug densities (975; 1,460; 1,820 and 3,500 mini-plugs.m-2) were tested in two phases, in growth chambers and in a nursery after transplanting the mini-plugs into larger containers. Measurements included seedling survival, growth traits (root length, shoot height, leaf area, root dry mass, shoot dry mass, root/shoot ratio) and root growth potential (RGP). In addition, the ratio of variable to maximal fluorescence (Fv/Fm) and the effective quantum yield of photosystem II (ΔF/F'm) were measured. It was found that growing medium produced significant effects mainly in the first phase and seed origin in the second phase while mini-plug density was important in both phases. The Fv/Fm ratio was found to be significantly affected by growing medium while the effective quantum yield was influenced by density. Early survival of seedlings was closely correlated with fluorescence and growth traits (particularly with plant height) suggesting that these parameters might be useful for the grading of black locust seedlings prior to transplanting.

Genotypic characterisation of the Erwinia genus by PCR-RFLP analysis of rpoS gene

M. Waleron, K. Waleron, E. Łojkowska

Plant Protect. Sci., 2002, 38(11):288-290 | DOI: 10.17221/10470-PPS

Genotypic characterisation of the members of the genus Erwinia, based on the PCR-RFLP analysis of a fragment of the rpoS gene was done. PCR primers deduced from described rpoS gene sequences of E. carotovora allowed the amplification of about 880 bp DNA fragments from all tested Erwinia species. The rpoS fragments, amplified from 20 species of the studied Erwinia genus, were compared by RFLP analysis with 4 enzymes (AluI, Hin6I, HinfI, and Tru1I). Restriction analysis allowed drawing 63 common profiles of RFLP products for all tested Erwinia. From 1 to 3 specific RFLP profiles were identified among most of the species tested. However, in two cases: E. chrysanthemi and E. c. subsp. carotovora 15 and 20 specific RFLP groups were detected, respectively. High variability of genetic profiles of the E. chrysanthemi and E. c. subsp. carotovora can be explained by the wide spectrum of plants, which they infect. The results indicated that rpoS PCR-RFLP analysis is a useful tool for identification of species and subspecies belonging to the former Erwinia genus, as well as for differentiation of strains within E. c. subsp. carotovora and E. chrysanthemi.

Biomass and catabolic diversity of microbial communities with long-term restoration, bare fallow and cropping history in Chinese Mollisols

G.H. Wang, J. Jin, X.L. Chen, J.D. Liu, X.B. Liu, Herbert S.J.

Plant Soil Environ., 2007, 53(4):177-185 | DOI: 10.17221/2313-PSE

Microbial biomass and community catabolic diversities at three depths (0-10 cm, 20-30 cm, and 40-50 cm) in Chinese Mollisols as influenced by long-term managements of natural restoration, cropping and bare fallow were investigated. Microbial biomass was estimated from chloroform fumigation-extraction and substrate-induced respiration (SIR), and catabolic diversity was determined by using Biolog® EcoPlate. Experimental results showed that microbial biomass significantly declined with soil depth in the treatments of restoration and cropping, and not in the treatment of bare fallow, where the microbial biomass had a positive relationship with the total soil C content. The inspections into the catabolic capability of the microbial community at the same soil depth showed that the treatment of natural restoration had a relatively stronger metabolic ability than the cropping and bare fallow treatments. Shannon"s diversity index, substrate richness and substrate evenness calculated from the Biolog data were higher in the treatments of natural restoration and cropping than the bare fallow treatment with the same soil depth, and with the highest values in the top soil. Principal component analysis indicated that the catabolic profiles not only varied with the soil depth in each treatment, but also differed in the three treatments within the same soil depth. The catabolic profiles of the three treatments were similar to each other in the soil depth of 0-10 cm and distinctly different in the soil depths of 20-30 cm and 40-50 cm. These results suggest that it was microbial biomass rather than community function that was influenced by the different soil management in the topsoil (0-10 cm); in the relative depths, the soil microbial community function was more easily influenced than microbial biomass.

Incidence of temperature-related abiotic diseases in Spanish garlic bulbs

J. Cabrera, F.J. López-Bellido, D. Recio, J.M. Alía, M. Serrano, C. Verdejo

Plant Protect. Sci., 2002, 38(11):696-699 | DOI: 10.17221/10593-PPS

Several alterations of growth physiology and bulb formation in garlic (Allium sativum L.) crops, such as "rough" and "burst" bulbs, have been related by different authors with low temperatures during bulbs storage and crop development. These physiopathies affect both the yield and the quality of garlic crops. Incidence of such diseases in Spanish garlic (variety "purple of Las Pedroñeras") were studied during two consecutive years. Experimental design was factorial taking the bulb storage temperature (5°, 10°, 15° and 20°C) as variable factor. Growth indexes during crop development and final quantity of defective bulbs were evaluated. Experimental results show significant differences between treatments, with the higher incidence of both physiopathies in those bulbs stored at 5°C. The 15°C and 20°C storage temperatures clearly reduce the risk of these abiotic diseases and tend to increase the yield and the final quality of the crop.

Mechanical behaviour under compression loading and some physical parameters of Japanese quail (Coturnix coturnix japonica) eggs

R. Polat, S. Tarhan, M. Çetin, U. Atay

Czech J. Anim. Sci., 2007, 52(2):50-56 | DOI: 10.17221/2262-CJAS

Technical information and data on the physical and mechanical properties of agricultural and animal products are necessary to design various equipments for agriculture and industry. In this study some physical properties such as mass, length, diameter, geometric mean diameter, surface area, sphericity, volume, coefficient of friction and packaging coefficient were determined for Japanese quail eggs. Furthermore, the mechanical behaviour of Japanese quail eggs was determined in terms of average rupture force, deformation and toughness (energy absorbed by the Japanese quail eggs per unit volume). Egg samples were compressed along their X and Z-axes. The average values of their mass, length, width, shell thickness, geometric mean diameter, surface area, sphericity, volume and packaging coefficient were measured to be 12.69 g, 34.87 mm, 26.20 mm, 0.27 mm, 28.82 mm, 2 608.5 mm2, 1.10, 359.17 mm3, 0.469, respectively. The values of the coefficient of friction for quail eggs on the surfaces of plywood, glass, galvanized steel and fibreglass were 0.301, 0.282, 0.274 and 0.266, respectively. The highest rupture force, deformation and toughness were obtained when Japanese quail eggs were loaded along their X-axis. Compression along the Z-axis required the least compressive force to break the eggs as compared to the other compression axes. Rupture force, deformation, absorbed energy and toughness for the X-front axis were determined to be 10.51 N, 1.5 mm, 7.88 Nmm and 0.219 Mj/mm2, respectively.

Potato tuber permittivity during deformation in compression

J. Blahovec, J. Sobotka

Res. Agr. Eng., 2007, 53(3):79-84 | DOI: 10.17221/2124-RAE

Potato tuber specimens of two varieties (Nicola and Saturna) were deformed in a compression loading/unloading test. The tuber complex permittivity spectrum at frequencies 0.1-500 kHz was measured repeatedly during the deformation. The results show that both parts of relative permittivity (real and imaginary) decrease with increasing deformation and vice versa. The same trend was observed at all studied frequencies even if it was not equally strong in all cases. The permittivity plots versus frequency were similar in both the tested varieties and in different stages of deformation. The influence of tuber deformation on the permittivity values as well as the reversibility of the permittivity changes during the deformation are changed substantially at strains about 20% in comparison to strains up to 10%. The obtained results support the hypothesis that permittivity measurements can serve as an alternative indication of the internal structural changes in potato tissue during its loading.

Antimutagenic effect of ellagic acid and its effect on the immune response in mice

P. Šmerák, H. Šestáková, Z. Polívková, I. Bárta, B. Turek, J. Bártová, M. Langová, M. Anděl

Czech J. Food Sci., 2002, 20(5):181-191 | DOI: 10.17221/3530-CJFS

Using the Ames bacterial mutagenicity test and an in vivo micronucleus test, we investigated the antigenotoxic effect of ellagic acid on the genotoxicity of three mutagens: amino-methylimidazo-quinoline (IQ), aflatoxin B1 (AFB1), and N-nitroso-N-methylurea (MNU). Ellagic acid is a naturally occurring phenolic compound which is found in a variety of soft fruits and vegetables. The effect of this compound on the immunosuppressive activity of mutagens was followed in vivo by the chemiluminescence test. In the Ames assay, ellagic acid at concentrations of 300 and 30 μg/plate demonstrably inhibits the mutagenic activity of two indirect mutagens: IQ and AFB1. The concentration of 300 μg/plate had the strongest effect on mutagenicity of all concentrations of IQ in strain TA98 of Salmonella typhimurium, whereas in strain TA100 concentration of 30 μg per dish of ellagic acid was more effective than 300 μg per plate. Also in combination with different concentrations of AFB1, ellagic acid proved to be a strong antimutagen. In this case the lower of the two effective concentrations - 30 μg/plate - had a much greater antimutagenic effect on both strains tested than 300 μg/plate. In combination with the direct mutagen MNU, ellagic acid did not show any marked antimutagenic effect at most of the concentrations tested in strain TA100. Only the highest concentrations of ellagic acid reduced the mutagenic effect of MNU weakly and only in combination with two lower concentrations of MNU. In the micronucleus test, three-day oral application of ellagic acid prior to the applicaton of AFB1, IQ, or MNU, respectively, markedly reduced the numbers of micronuclei induced by these three mutagens in polychromatophilic erythrocytes of mice. Chemiluminescence test with mouse granulocytes proved that ellagic acid not only prevents the inhibitory effects of mutagens on free oxygen radicals and hydrogen peroxide production, but that this production is stimulated by ellagic acid in combination with mutagens even to a greater extent than by ellagic acid alone. From these results we can deduce that ellagic acid repairs strong immunosuppressive effects of all mutagens applied.

Natural forest regeneration in spruce monocultures in the Ukrainian Beskids - prognosis by FORKOME model

I. Kozak, V. Parpan, G. Potaczala, H. Kozak, A. Zawadzki

J. For. Sci., 2007, 53(4):162-169 | DOI: 10.17221/2355-JFS

This paper presents the results of investigations on natural forest regeneration in Norway spruce (Picea abies L. Karst.) monocultures in the Ukrainian Beskids with the use of FORKOME model prognostic possibilities. Different variants of regeneration methods are presented. Selective cutting with planting was determined as the most effective: spruce selective cutting with simultaneous planting of target species: beech (Fagus sylvatica L.) and fir (Abies alba Mill.) with admixture of ash (Fraxinus excelsior L.). Beech and fir biomass increases rapidly over the first 20 years - then it stabilizes. After another 20-30 years the initial form of beech forest is recognizable and it is possible to speak about an increase of beech forest, which in the course of time achieves a higher degree of similarity to natural stand. In the Ukrainian Beskids the potential forest stand consists of beech and fir (Dentario glandulosae-Fagetum).

Free and bound 3-chloropropane-1,2-diol in coffee surrogates and malts

Veronika Divinová, Marek Doležal, Jan Velíšek

Czech J. Food Sci., 2007, 25(1):39-47 | DOI: 10.17221/735-CJFS

The levels are reported of the free 3-chloropropane-1,2-diol (3-MCPD), its bound forms, the recognised precursors of 3-MCPD, and the factors influencing its formation in 5 selected coffee surrogates and 18 malts in the Czech Republic. The coffee surrogates had the free 3-MCPD level in the range of < 9.0 to 32 µg/kg while the highest amount was found in roasted barley. In malts, the free 3-MCPD levels were similarly low (< 9.0 to 45 µg/kg) being the highest in roasted malts (16-45 µg/kg). Nevertheless, the values found in either surrogates or malts, calculated after normalisation to 40% dry matter content, did not exceed the European Union limit of 20 µg/kg adopted for soy sauces and acid-HVP. The risk for consumers could arise from the bound 3-MCPD, its elevated levels having been found in both coffee surrogates and malts. In coffee surrogates, the bound 3-MCPD levels varied between 145-1184 µg/kg product; the highest level was found in roasted barley. The bound 3-MCPD levels exceeded the free 3-MCPD levels 32 to 81 times. In malts, the bound 3-MCPD levels ranged from 4.0-650 µg/kg, the highest amount having been found in roasted malts (463-650 µg/kg). The bound 3-MCPD levels exceeded the free 3-MCPD levels 0.4 to 36 times.

The accumulation of zinc in oat grown in soils treated by incubated sewage sludge with peat and straw

J. Balík, P. Tlustoš, J. Száková, D. Pavlíková, J. Černý

Plant Soil Environ., 2002, 48(12):548-555 | DOI: 10.17221/4411-PSE

The effect of addition of treated sewage sludge on the accumulation of Zn in plants was tested in pot experiment. The additions of eight months preincubated sewage sludge at temperature of 20°C under aerobic and anaerobic conditions with addition of peat and straw were tested. Two different combinations were designed: first consisted of 50% sludge + 35% peat and 15% straw, and second was made of 50% sludge + 5% peat and 45% straw (expressed as dry matter). Three different soils Chernozems, Luvisols, and Fluvisols and three sludges were tested in the experiment. Oat (cv. Pan) was planted as experimental crop. All treatments were fertilized by NPK. Green biomass of oat was harvested and analyzed. At treatments with addition of both composted sludges pH dropped down causing higher mobility of Zn in sewage sludge. Oat grown in these treatments contained higher amount of Zn compared to untreated soils. The application of anaerobically treated sludge led to increased Zn content in biomass compared to aerobically incubated one. Predominant effect on Zn accumulation in plants was determined by tested soil. The highest content was determined in plants grown on Fluvisols. The biomass yield was more affected by source of sewage sludge than by the soil type used. Treatments amended by anaerobically incubated sludge showed tendency to higher biomass production due to their higher content of nitrogen and carbon.

Physiological nature of overwintering oats forms

J. Petr, I. Capouchová, M. Štolcová

Plant Soil Environ., 2002, 48(7):285-292 | DOI: 10.17221/4371-PSE

We evaluated the need for low temperatures (vernalization) and the photoperiodic reaction of three collections of winter oats (1. Pedarn, Maris Quest, Peniarth; 2. Gerald, Solva, Kymon, Pendragon; 3. Pewi, Silwi, Wiskas) in a comparison with spring oats varieties. All three collections of varieties showed little need for low temperatures, mostly as few as 10-20 days, which does not represent an obligatory need; this influence is only quantitative and constitutes no precondition for a passage of plants into the generative stage. Only in the case of the Maris Quest variety, the need for vernalization approached 30 days. As compared with the reaction of winter barley varieties that had and in some cases still have worse overwintering in the Czech Republic, the length of vernalization is equal. In the photoperiodic experiment, the reaction to a short autumn day turned out to be the critical condition for a possibility of autumn sowing and overwintering; in the case of these varieties, a short day inhibits the development until arrival of winter. We evaluated this reaction according to the length of the induction period. This period was only 10-15 days in the case of the spring oats Český žlutý, 30 days in the case of winter oats Maris Quest, 25 days for Pedarn, 20 days for Peniarth and 21 days for Pendra-gon; the induction period was 14-21 days in the case of varieties Gerald, Kymon and Solva. When compared with figures for winter barley, it had the longer photoperiodic induction period. The evaluated varieties of winter oats do not reach such a degree of a reaction to a short day, which manifests itself in their lower frosthardiness than that of winter barley. We verified that in provoking tests for frosthardiness, and also by lower critical values of temperatures for dying out of 50% of plants, the so-called LT 50.

Water infiltration into soil related to the soil tillage intensityOriginal Paper

Milan Kroulík, Josef Hůla, Rudolf Šindelář, František Illek

Soil & Water Res., 2007, 2(1):15-24 | DOI: 10.17221/2098-SWR

Soil infiltration capacity is one of the key factors in the soil protection against unfavourable effects of water erosion. The purpose of its measuring was to compare and evaluate the changes of the soil physical properties and of water infiltration into soil caused by different intensity of soil cultivation at two individual sites. The ploughing (PL), shallow tillage (ST), and direct drilling (NT) effects on the soil physical properties, water infiltration into soil, and soil surface coverage with the crop residua under the soil condition loamy Haplic Luvisol, with long-term growing of maize (Zea mays L.) - Agroservis, 1st Agricultural, a.s., Višňové - and clay soil of Calcic Chernozem (Cooperative farm Klapý), were compared. Soil bulk density values in the variant with ploughing showed in the depth up to 0.20 m considerably lower values as compared with the variants shallow tillage and direct drilling. Nevertheless, in the subsoil layer the bulk density of soil in the variant with ploughing increased in comparison with other variants. The results were also confirmed by the cone index values. At the plots in Višňové the infiltration was evaluated utilising the double ring infiltrometer, and by means of the coloured water infiltration. The results revealed significant differences in the water infiltration rate at various stages of the soil loosening. The highest average values were recorded for ploughing (1.00 dm3/min). The lowest values were found for the shallow soil tillage (0.18 dm3/min). The variant with direct drilling showed values of 0.53 dm3/min. The coloured water infiltration evaluation showed a different character of water flow in soil. The variant with ploughing showed water saturation in the top layer, the variants with reduced tillage were characterised by vertical macropores and crack effects with the water drain into deeper layers. Ploughing proved its advantage for the short-term rainfall retention. Similar results were also brought in the evaluation on the plot with clay soil (Klapý). The loosening effect was evident during coloured water infiltration in the period of snow thawing. The loosed soil layer showed a significantly higher soil water holding capacity as compared with variants with reduced soil tillage. The result showed major differences in the water infiltration rate into soil and different characters of water infiltration into soil at different soil tillage.

The effect of simultaneous magnesium application on the biological effects of titanium

S. Kužel, P. Cígler, M. Hrubý, J. Vydra, D. Pavlíková, P. Tlustoš

Plant Soil Environ., 2007, 53(1):16-23 | DOI: 10.17221/3189-PSE

Most of the works published since the beginning of the 20th century have brought interesting results about beneficial effects of titanium (Ti) on plants, but much less is known about its phytotoxic effects at higher doses. Here we demonstrate the influence of Mg treatment on the phytotoxic effects of Ti. Mg, Ti + Mg and two different concentrations of Ti leaf sprays were applied on oats (Avena sativa L. cv. Zlaťák) grown on three different soil types (Fluvisol, Luvisol and Chernozem). Physiological parameters of oats as well as some essential elements contents were analyzed. The foliar applications of Ti caused significant toxic manifestations on oats at ≥ 10 mg/kg concentrations. Mg partially ammeliorates these toxic effects if applied together with Ti. The effect was strong on Fluvisol, but weaker on Chernozem and Luvisol. Ti effects are more significant the further the soil is from the nutritional optimum of the plants. This is most evident in the case of Fluvisol, which is deficient in Mg, Fe, Mn, and Zn. It seems that Ti possesses a generally equalizing effect on the elements content in the plant.

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.

Parametric analysis of the properties of selected mixing feeding wagons

J. Vegricht, P. Miláček, P. Ambrož, A. Machálek

Res. Agr. Eng., 2007, 53(3):85-93 | DOI: 10.17221/2123-RAE

Eight different mixing feeding wagons (MFW) were investigated under identical conditions in preparing total mixed rations (TMR) for three various cattle categories. Investigated were the uniformity of distribution of the feed into the trough, homogeneity of TMR distributed, the machine capacity in feed extracting from storage and loading, TMR mixing and distributing into the trough, fuel consumption and power consumption required. The least uniformity was found for TMR with a high hay proportion (average value of standard deviation 49.9%). Better results were achieved with MFW designed with horizontal mixing augers (average standard deviation 33.7%). MFW with vertical augers distributed feeds at average standard deviation of 61.3%. Standard deviation of the proportion of feed particles on the separator screens which is considered as a measure of TMR homogeneity, was bellow 20% in most cases. This suggests a hint of a very good mixing efficiency of all the MFW followed up. No influence of different designs of the working elements of MFW on TMR homogeneity has been proved. With respect to the machine capacity (output) in preparing and distributing TMR, no large differences between various MFW were found and their output averaged from all measurements varied within the range of 4.79-5.48 t/h. The least average specific consumption of fuel for preparing and distributing TMR was found in the MFW equipped with vertical mixing augers (1.10-1.11 l/t). MFW with one horizontally mounted mixing auger showed a rather higher fuel consumption (1.30-1.43 l/t). The highest fuel consumption was found with MFW equipped with two parallely mounted mixing augers (1.59-1.63 l/t).

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.

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%).

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.

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.

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.

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.

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).

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.

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