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Results 4831 to 4860 of 5716:

Altitude and forest type effects on soils in the Jizera Mountains regionOriginal Paper

Lenka Pavlů, Luboš Borůvka, Antonín Nikodem, Marcela Rohošková, Vít Penížek

Soil & Water Res., 2007, 2(2):35-44 | DOI: 10.17221/2114-SWR

This paper is focused on the Jizera Mountains as a region strongly influenced by man in the past. The structure of the natural forest was changed. Species monocultures with similar tree ages were planted. High acidificants concentrations in atmosphere led to the decline of these monoculture forests in the top parts of the mountains and the high acidificants deposition damaged the soils in the whole region. The goals of this study are to describe the distribution of the soil properties in altitude transects, where temperature, precipitation, and vegetation gradients are recorded, and to compare the soil properties in spruce and beech forests. The soil samples were collected from soil pits in a surviving nature-close beech forest, in a production spruce forest, and also in the top dead forest area with a grass cover. Soil samples from sufficiently deep diagnostic horizons were taken for the study of chemical properties. The basic soil characteristics were determined by the commonly used methods (pH, effective cation exchange capacity - eCEC, and the contents of cations in the sorption complex, A400/A600 as humus quality parameter, the contents of available Ca, Mg, K and P, pseudototal content of Ca and Mg, and two differently extracted Fe and Al forms contents). The soils of the Jizera Mts. are strongly acid with a low eCEC which is the result of the natural and anthropogenic acidification processes. Soil chemical properties of the most affected top mountainous parts are in some aspects more favourable than lower parts (binding of potentially toxic Al in organic matter, slightly higher pH), but in other aspects they are still endangered by the acidification symptoms (higher leaching of base cations, especially Mg). The soils of nature-close beech forests represent more favourable soil properties than those of planted spruce forests. Generally, it can be concluded that the natural systems have higher resilience, and that natural mechanisms are able to mitigate slightly the soil degradation.

The renewal of the rural cultural heritage of the Czech Republic with the support of regional policy

H. Hudečková, A. Ševčíková

Agric. Econ. - Czech, 2007, 53(11):505-512 | DOI: 10.17221/2676-AGRICECON

The paper focuses on rural immovable cultural heritage as a part of the infrastructure for certain forms of tourism. Using the secondary analysis method, it compares data about the support of rural cultural heritage in the pre-accession period (2002) and after the Czech Republic joined the EU (2004-2006). Conclusions include a broader issue of animation of cultural heritage for the purpose of rural development.

Growth reaction of young wild cherry (Prunus aviumL.) trees to pruning

I. Kupka

J. For. Sci., 2007, 53(12):555-560 | DOI: 10.17221/2165-JFS

A large crown is one of the most important prerequisites for the good growth of a tree and therefore the crown could be called an engine of increment. The care for a large crown brings a decrease in the bole value at the same time as it makes large branches and later knots on it. Pruning is a possible solution of these two contradictions. Young wild cherry trees were pruned in three different ways: (i) half of the crown left, (ii) one quarter of the crown left and (iii) control, i.e. no pruning. The results show that height growth was not influenced by pruning while diameter growth was significantly affected. The crown reduction to a half means 10% less in diameter growth within a 5-year period after pruning. The crown reduction to one quarter of the crown means only two thirds of 'full' diameter growth on the control plot. The data suggest that the pruning of young wild cherry trees should be done moderately (more than a half of the crown should be left) and pruning should be done when the bottom part of the crown is in the shadow zone of the crown layer, not earlier.

Bread features evaluation by NIR analysis

Ondřej Jirsa, Marie Hrušková, Ivan Švec

Czech J. Food Sci., 2007, 25(5):243-248 | DOI: 10.17221/683-CJFS

Bakery characteristics of wheat dough and the final product and their predictability by NIR technique was investigated using 231 variety and commercial wheat samples (crop years 2003-2005). The behaviour of doughs was assessed with Brabender maturograph and OTG (Germany), the final product quality was evaluated by the baking test and image analysis. NIR spectra of flours were acquired on a NIRSystem 6500 spectrometer. Calibration equations for the selected rheological characteristics were computed by WINISI II using mPLS regression. The quality of prediction was evaluated by means of coefficients of correlation between measured and predicted values from cross and independent validation. A statistically significant dependence (with probability higher than 99%) was found with all rheological characteristics. The standard errors of cross-validation were achieved as follows: dough elasticity 16 BU, bread volume (11 min) 58 BU, specific loaf volume 34 cm3/100 g, bread cut area 2.6 cm2, penetration 4.1 mm, average cell area 0.4 mm2 and cells per cm2 7.4.

The development of above-ground biomass in unmanaged grasslands and its influence on the leakage of water and the amount of elements found

J. Fiala

Plant Soil Environ., 2007, 53(1):42-50 | DOI: 10.17221/3192-PSE

The influence of various forms of farming on unmanaged grasslands was monitored with regard to the accumulation of the above-ground biomass (litter + mulching) and its influence on the leakage of rainfall and the amount of elements in lysimetric waters. In 2001-2005, the highest accumulation was observed in variants 1× mulched in the later term and on green fallow (on average 2.11-1.13 t of dry matter/ha). In comparison with the control site, a conclusive increase always occurred. An interannual increase of dry matter amounted to 0.4-5.2% of the total above-ground biomass. A negative correlative dependency on rainfall leakage on this material was discovered; at a depth of 0.4 m 4-10% of the rainfall leaked, but it had a significant influence on the wash out of Ca, Mg and S. The leakage of water affected a wash out of Nmin, P, K, Ca, Mg and S more than the weight of dry matter of the above-ground biomass. With the exception of P, the elements showed a downward tendency over five years. The above-mentioned forms of farming annually increased the accumulation of the above-ground biomass by 0.05-0.16 t of dry matter/ha; however, they do not endanger underground waters by washing out minerals. After a five-year period, a disturbance of the ecological stability of grassland did not occur.

Mapping of non-recombining regions via molecular markers

B. Janoušek, J. Žlůvová

Plant Soil Environ., 2007, 53(7):321-324 | DOI: 10.17221/2207-PSE

The lack of recombination in some genomic regions represents a serious obstacle in mapping studies. In this review, we describe methods that are currently used to overcome this problem. Main attention is given to the comparison of methods that are based on the principle of radiation hybrid mapping. We also discuss a strategy called HAPPY mapping (mapping based on the analysis of approximately HAPloid DNA samples using the PolYmerase chain reaction). In addition to reviewing the methods used by other authors, we also summarize our experience with deletion mapping of Y-chromosome in dioecious model plant species (Silene latifolia).

Emmer wheat Rudico can extend the spectra of cultivated plants - Short Communication

Zdeněk Stehno

Czech J. Genet. Plant Breed., 2007, 43(3):113-115 | DOI: 10.17221/2072-CJGPB

Emmer wheat (Triticum dicoccum Schübl. or also T. dicoccon Schrank) tetraploid wheat species was grown in the Czech territory till the 6th century A.D. when it was replaced by bread wheat. At present only landraces and wild forms of this species are available in collections of genetic resources. With the aim to extend the spectra of grown crops, a collection of emmer genetic resources in the Czech Gene Bank was studied. An accession later in ripeness, with a good level of resistance to fungal diseases and with a high yield potential was selected from the collection. After bulk selection procedure and three year testing it gained a certificate of legal protection as cultivar Rudico. The cultivar with high protein content and very good resistance to fungal diseases was found to be able to meet the requirements for organic growing systems as well.

Functional state of mammary gland of sows dried off by different techniques

A. Rekiel, K. Czumińska, J. Więcek, W. Bielecki, J. Kulisiewicz

Czech J. Anim. Sci., 2007, 52(3):62-69 | DOI: 10.17221/2358-CJAS

Sows were dried off by a traditional method (control - C, restricted feeding before, during and after weaning) or by a modified one (experimental - E, intensive feeding before, during and after weaning). On day 5-6 after weaning of the 3

Critical values of trace elements in soils from the viewpoint of the transfer pathway soil - plant

E. Podlešáková, J. Němeček, R. Vácha

Plant Soil Environ., 2002, 48(5):193-202 | DOI: 10.17221/4224-PSE

The development of soil limiting values of the protection of the quantity and mainly quality of the crop production tends from empiric values towards critical values, based on ecotoxicity. We present an attempt to derive transfer functions by the means of multiple regression analysis. The substitution of trace elements contents in crops in the prediction equations for fodder or food standards or phytotoxicity limits satisfies the present ecotoxicological demands. We preferred polyfactor relations to simple ones. The exceeding of reference values must be verified by the determination of the hazardous transfer in the field. Therefore the reference values are called testing values. They were derived especially for Cd, Pb, As, Cu, Zn, Ni and Mn. For some trace elements, only protective values can be set up (especially for Cr, Hg, but also for Tl, Be, V). They reflect minimum values that guarantee growing crops without any risks. Experimental data (pot trials) were compared with results obtained in field investigations. The resulting critical values were also compared with the values proposed in Germany.

Spatial aspects of the Sectoral Operational Programme - Agriculture and Rural Development - implementation in the Slovak Republic

S. Buchta, Z. Rentková

Agric. Econ. - Czech, 2007, 53(5):217-223 | DOI: 10.17221/1446-AGRICECON

The contribution deals with the spatial distribution of approved projects under the Sectoral Operational Programme - Agriculture and Rural Development (SOP ARD) in the programme period 2004-2006. The approved projects from agrifood industry were concentrated in the production regions of western and southern Slovakia. It does not indicate only the high absorption capacity of the enterprise subjects, but also really well prepared projects in these regions. In the next programme period, we will have to count with unevenly distributed projects. On the other hand, the low absorption ability in the northern and mainly eastern areas of the SR may result in forming the islands of extreme extensity with negative socio-economical impacts. The SOP ARD (analogous to Sapard) accelerates the process of enterprising selection and significantly supports the increase of competitiveness in economically powerful farms.

The conditions of organic market developmenti

I. Živělová, J. Jánský

Agric. Econ. - Czech, 2007, 53(9):403-410 | DOI: 10.17221/635-AGRICECON

The aim of the paper is the evaluation of the present sale of the chosen organic products in the condition of the Czech Republic. The sale analysis is made according to the structure of plant and animal products with the help of both qualitative and quantitative evaluation parameters as for example the amount of production and their prices, sales conditions and the used distribution channels. The part of the paper is also analyses of present state of demand for chosen organic foodstuff and of the consumer's interest in organic foodstuff. The attention is paid mainly to the recognition of the consumer's interest in organic foodstuff, for the consumer's interest is the limit factor of the demand for organic products.

Effect of hydrogel application on survival and growth of pine seedlings in reclamations

M. Sarvaš, P. Pavlenda, E. Takáčová

J. For. Sci., 2007, 53(5):203-209 | DOI: 10.17221/2178-JFS

In this study results of hydrogel application in reclamations are presented. The application of hydrogel affected the survival of pine seedlings during two vegetation periods after planting. Double application of STOCKOSORB AGRO (gel) on the root system after lifting caused an about 19% higher survival rate compared to control variants. The application of 7 g/planting hole of STOCKOSORB MICRO granules caused overdosage and plant mortality. The application of hydrogel granules is simple but it is very complicated not to cause the overdosage because of the very high swelling capacity of hydrogel. Research should be carried out to determine suitable hydrogel application rates for different environmental conditions and tree species. To design a technology with regard to the economic effectiveness of application will be a very important task.

A short guide to phylogeny reconstruction

E. Michu

Plant Soil Environ., 2007, 53(10):442-446 | DOI: 10.17221/2194-PSE

This review is a short introduction to phylogenetic analysis. Phylogenetic analysis allows comprehensive understanding of the origin and evolution of species. Generally, it is possible to construct the phylogenetic trees according to different features and characters (e.g. morphological and anatomical characters, RAPD patterns, FISH patterns, sequences of DNA/RNA and amino acid sequences). The DNA sequences are preferable for phylogenetic analyses of closely related species. On the other hand, the amino acid sequences are used for phylogenetic analyses of more distant relationships. The sequences can be analysed using many computer programs. The methods most often used for phylogenetic analyses are neighbor-joining (NJ), maximum parsimony (MP), maximum likelihood (ML) and Bayesian inference.

Winter oilseed rape Aplaus

I. Macháčková

Czech J. Genet. Plant Breed., 2007, 43(1):33-34 | DOI: 10.17221/1902-CJGPB

Analysis of linear description of type traits in the varieties and studs of the Old Kladrub horse

V. Jakubec, M. Rejfková, J. Volenec, I. Majzlík, L. Vostrý

Czech J. Anim. Sci., 2007, 52(9):299-307 | DOI: 10.17221/2265-CJAS

An evaluation of the linear description of type in 494 horses of the Old Kladrub breed for 32 traits was used to analyse the effect of variety, stud, sex, year of birth and age at description. A linear model with fixed effects was used. The highest coefficient of variation was calculated for the forelimb side-view (40.14%), chest girth (36.25%) and height at withers (30.97%). 28 out of 32 traits were in the range from 7 to 9 utilized scores. The descriptor used a very high number of scores of the scale. Significant differences between both varieties were found in 13 out of 32 traits. Significant differences were found in 12 out of 32 traits between the Kladruby stud farm and the private studs. There is no reasonable explanation of this fact. A significant variety × stud interaction was recorded in only 7 traits. Significant differences between stallions and mares were recorded in a large number of front and body traits (in 11 out of 18 traits) and in 2 rear traits. Despite of a remarkable number of significant differences between the years of birth (in 18 out of 32 traits) and age at description (in 13 out of 32 traits) both factors are not the important ones for the selection of horses according to the type traits. The description of type traits, performance recording and selection are carried out in the population of four-years-old horses born in the given year. The age at description does not play a role because all horses are now described each year at a standard age of four years. The linear description of type is an important tool for the breeding and conservation of genetic diversity within the breed.

Land market development after the accession to EU

J. Němec, J. Kučera

Agric. Econ. - Czech, 2007, 53(4):154-160 | DOI: 10.17221/866-AGRICECON

Land market has started to develop extremely in the Czech Republic since 2002. The annual sale and purchase of estates represented 0.2% of the total land resources between 1993-2001. The sale and the purchase have represented 2.9% of total land resources after 2002 and especially after the EU accession of the Czech Republic. These values of sale are the highest from the EU countries. On the other side, land prices decreased slightly in comparison with the prices before the EU accession. Prices of agricultural land are significantly lower than in the EU 15.

Field Determination of the Specific Input Characteristics to Calculate the Value of C Factor of Time-variable Crops for the Revised Universal Soil Loss Equation (RUSLE)Original Paper

Alena Jakubíková, Miloslav Janeček, Martin Tippl

Soil & Water Res., 2006, 1(1):10-15 | DOI: 10.17221/6500-SWR

To determine specific characteristics necessary for the computation of the C factor in RUSLE for timevariable crops, measurements were carried out in fields with selected agricultural crops grown by conventional practices. Sloping plots on an experimental area in Třebsin locality and farm fields were used to measure surface runoff and soil loss by erosion in conditions of natural and simulated rainfall. Basic characteristics to compute the C factor were determined in the particular growth phases of selected crops - sunflower, flax, poppy and rape. Effective root mass, canopy cover and fall height of rain drops were measured.

Marketing attitudes towards the functional food and implications for market segmentation

E. Horská, K. Sparke

Agric. Econ. - Czech, 2007, 53(8):349-353 | DOI: 10.17221/1148-AGRICECON

The main purpose of this paper is to investigate the opportunities for further expansion in the segment of the functional food as highly innovative products based on market segmentation done from the consumer perspective. The survey analysed consumers and their relationship to Functional Food. The relationship between nutrition and health was evaluated as well as their trust towards some actors in the field of food, e.g. producers and retailers and their promotion claims on the one side and medical doctors and nutritional consultants and their advices on the other side. Germany, Poland, Spain and England were the analyzed countries of this survey. About 600 consumers have been interviewed. Afterwards they were grouped into five segments of buyers and three groups of non-buyers of Functional Food.

Terrain properties of selected forest sites in the Jizerské hory Mts., Czech RepublicOriginal Paper

M. Modrý, V. Simanov

J. For. Sci., 2002, 48(7):310-319 | DOI: 10.17221/11890-JFS

Differentiation of forest technologies according to ecosystem properties is a necessary step to achieve sustainable forestry. A forest typological system is considered to be the basic unit of ecosystem differentiation in the Czech Republic. Terrain characteristics, potential water erosion and applicable harvest technology were examined for 44 forest sites in a landscape segment of the Jizerské hory Mts. Forest site was found homogeneous in terms of terrain and technological properties. Edaphic category and groups of forest types as higher classification units and management sets as units of alternative classification showed lower homogeneity insufficient for operational planning.

European brown hare as a potential source of zoonotic agents

F. Treml, J. Pikula, H. Bandouchova, J. Horakova

Vet Med - Czech, 2007, 52(10):451-456 | DOI: 10.17221/2050-VETMED

There has recently been a growing interest in checking the state of health of European brown hares in hunting grounds because they are a susceptible bio-indicator of environmental changes and because of the dramatic decline in populations across Europe. A total of 1 051 (384, 302, and 365, respectively) blood sera were collected from hares during autumn hunting events and examined for tularaemia, brucellosis and leptospirosis in 2004, 2005 and 2006. Antibodies were found in 6.5, 1.6 and 7.5% of cases, respectively. Antibodies against Francisella tularensis, Brucella suis and leptospires were found in 7.9, 1.7 and 7.7% of females and 4.5, 1.4 and 7.9% of males, respectively. Higher seroprevalence of tularaemia was found in females (P = 0.05). Brucellosis was more prevalent in adult animals compared to subadult ones (P = 0.05). Only the L. grippotyphosa serotype was found and the titres mostly ranged from 100 to 400 (89.9%). Higher titres from 800 to 3 200 were found in the remaining 10.1% of the examined European brown hare sera. Antibodies against F. tularensis as well as B. suis were most frequent in low titres of 10 to 80. Higher titres were only exceptional. Confirming that hares are susceptible to various zoonotic agents, it is necessary to be careful when handling the animals killed. On the other hand, blood sera from hares may be used to survey the occurrence of natural nidi of zoonoses in hunting grounds.

Mineral nutrition in relation to the Norway spruce forest decline in the region Horny Spis (Northern Slovakia)

Ľ. Ditmarová, J. Kmeť, M. Ježík, J. Váľka

J. For. Sci., 2007, 53(3):93-100 | DOI: 10.17221/2148-JFS

In this contribution we present the results of analyses of selected mineral nutrients in assimilatory tissues of spruce trees at different developmental phases (plants, adult trees) in the region Horný Spiš. The very close connection between mineral nutrient cycling and other physiological processes in the plants has been well recognised. The presented analyses of mineral nutrient cycling were done within comprehensive eco-physiological research assessing the physiology and health status of spruce stands in the study area. The research was conducted directly in the stand (Hliníky locality, Horný Spiš - two research plots: 1. plot with spruce stand in advanced decline, 2. control plot - without visible decline symptoms) and, at the same time as a pot experiment. The objective of the pot experiment was to verify the supposed negative influence of soil environment (in the locality with advanced decline of spruce stands) on the growth of spruce trees and their mineral nutrient conditions. The analyses of the material sampled from the stands revealed high amounts of manganese (MnT) that were in the toxicity range on both examined plots. Another negative finding was high amounts of toxic aluminium, primarily in needles of adult trees growing on the plot with symptoms of acute stand decline. This reflects a very low value of pH/H2O - 3.7 (pH/KCl - 3 to 2.8) and total exhaustion of the soil suffering, moreover, from the lack of soil water. As for the differences in amounts of individual macronutrients between the plot with intensive decline and the control plot, no significant differences were found, with the exception of Fe. On the other hand, evident significant differences in risk elements Pb, Hg and Al were found. As for the differences in nutrient contents in spruce seedlings in the pot experiment (variants 1 to 6), we can see significant differences in macronutrient contents (N, P, Ca, K, Mn), in some cases also in risk element contents (Al).

Game damage to forest trees

V. Malík, P. Karnet

J. For. Sci., 2007, 53(9):406-412 | DOI: 10.17221/2143-JFS

Humans should behave in such a way that they will not endanger the existence of other living entities. After all, human activities affected the tree species composition and wildlife living conditions. Humans are now responsible for the preservation of delicate equilibrium in nature. Two localities were chosen for the research of game damage caused to standing trees - shooting areas Lužánky and Červený jelen, both situated in the vicinity of Jindřichův Hradec in South Bohemia. Seasonal character of tree-damage origin as well as its relation to the chemical content of spruce (Picea abies [L.] Karst.) and pine (Pinus sylvestris [L.]) bark were investigated. This area is typical of high game stock; trees are damaged by browsing and bark stripping. Particular advice for game management with respect to minimizing tree damage is presented. The data set of chemical bark analyses was statistically evaluated by t- and F-test and significant differences in element contents were detected between damaged and undamaged pine bark for N-substances (P = 0.003309), Ca (P = 0.001460), P (P = 0.004343), Mg (P = 0.001419) and K (P = 0.016290). Humans have influenced many changes in the distribution of different animal and plant species. Among others they are responsible for the altered species composition. Typically the extinction of large predators produces changes in food chains. In forest stands influenced by human activities the reasonable game management and the regulation of game stock seems to be one of the main tools in forest protection.

Web-spinning sawflies of the genus Cephalcia Panzer (Hymenoptera, Pamphiliidae) in the Picea abies forests of the Beskidy Mountains (Poland)

M. Jachym

J. For. Sci., 2007, 53(20):63-68 | DOI: 10.17221/2149-JFS

This article presents a review of data and results of investigations from the period 1958-2006 regarding the occurrence of insects of the genus Cephalcia Panzer (Hymenoptera, Pamphiliidae) in Norway spruce stands of the Beskidy Mountains (Western Carpathians, southern Poland). Currently, eight species are known for the area: C. abietis, C. alashanica, C. alpina, C. annulicornis, C. arvensis, C. erythrogaster, C. fulva and C. masuttii. Information regarding each species is given, with details on identification, local occurrence and importance.

Effect of foliar urea application on quality, growth, mineral uptake and yield of broccoli (Brassica oleracea L., var. italica)

E. Yildirim, I. Guvenc, M. Turan, A. Karatas

Plant Soil Environ., 2007, 53(3):120-128 | DOI: 10.17221/2227-PSE

The objective of this study was to determine the effect of foliar urea applications on quality, growth, mineral content and yield of broccoli under field conditions in 2003, 2004 and 2005. Broccoli cultivars AG 3317 and AG 3324 were treated with foliar urea applications at different concentrations (0.0, 0.4, 0.8 and 1.0%). Foliar applications of urea, especially 0.8 and 1.0% resulted in larger heads, weightier heads and plants as well as higher plants. Conversely, the greatest head and leaf dry matter contents were obtained with no fertilizer-nitrogen application. SPAD chlorophyll readings that were measured in the third year increased with elevated urea concentrations. In regard to the nutrient content, it can be interfered that soil nitrogen fertilization and foliar urea applications increased the content of almost all nutrients in leaves and heads of both broccoli cultivars in three experiment years. Generally, the greatest values were obtained from 1.0% urea application for both cultivars. It results from the study that for optimum yields 0.61 and 0.96% concentrations of urea sprays could be successfully used to obtain better growth and yield in broccoli cultivars AG 3317 and AG 3324, respectively.

Spring malt barley response to elemental sulphur - the prognostic value of N and S concentrations in malt barley leaves

W. Grzebisz, K. Przygocka-Cyna

Plant Soil Environ., 2007, 53(9):388-394 | DOI: 10.17221/2295-PSE

The basic concept of malt barley production is to reach a dilution effect of nitrogen accumulated by grains at maturity. A three-year study was undertaken to establish time courses of nitrogen (N) and sulphur (S) in leaves as the prerequisite tool for total grain yield prognosis. Sulphur application at the lowest rate of 25 kg/ha significantly increased yields of grain in 2001 and 2003. The time course of N and S concentrations in leaves over the growing season showed declining trends for N and variable for S. At mid tillering (BBA-25) both N and S, but at BBA-31 only N concentrations significantly responded to S rates, and in turn affected patterns of N concentration in barley organs up to maturity. Sulphur concentrations and N:S ratios were useful tools to make reliable prognosis of total grain yield of barley at BBA-31 as indicated by the obtained regression equations. The threshold values for N and S in leaves in order to achieve the maximum total grain yield are 0.4% for S and 8.0 for the N:S ratio as presented by the graphical procedure.

Effect of slow release fertilizers on container-grown woody plants

F. Šrámek, M. Dubský

Hort. Sci. (Prague), 2007, 34(1):35-41 | DOI: 10.17221/1844-HORTSCI

Slow-Release Fertilizers (SRF) Silvamix Forte and Silvagen were tested in two-year experiments with container-grown woody plants (Pyracantha coccinea, Thuja occidentalis). Several fertilizing systems were compared: preplant application of SRF into substrate as the sole nutrient source for a two-year period, preplant application of SRF and soluble fertilizer (PG Mix), and preplant application of SRF and soluble fertilizer together with additional fertilizing by solution of nitrogen fertilizer during both growing periods. A system with controlled-release fertilizer (CRF) Osmocote 5-6 was chosen as a control variant; it was incorporated into substrate before planting in the first year and top-dressed in the second year. CRF Plantacote 6M (mixed into substrate before planting and top-dressed in the second year) and Osmocote 16-18 applied only before planting were tested, too. The experiments showed that SRF Silvamix Forte and Silvagen give results comparable with CFR provided that they were incorporated together with soluble ferti-lizer dose and plants were fertilized by solution of nitrogen fertilizer during both growing periods.

The bonsai management

P. Tomšík

Agric. Econ. - Czech, 2007, 53(7):291-297 | DOI: 10.17221/1150-AGRICECON

Management can be understood as a "bonsai" integrating its roots in long-term bases with the trunk of general management growing from it supporting a cultivated treetop branching out in the real time. Managers need to develop a new understanding of the management process that will respond to global trends in the world's economy. More precisely it needs to create more progressive management styles. Management will be successful if it is based upon people's own knowledge and their development. In addition it has to look beyond the confines of the company and even of the country and to take into account the on-going and permanent development of technology. With particular regard to technology, man should be seen as a bearer of knowledge, regarded as an investment and seen as a source of long-term profit.

The effect of the soil compaction on the contents of alfalfa root reserve nutrients in relation to the stand density and the amount of root biomassOriginal Paper

Josef Hakl, Jaromír Šantrůček, Daniela Kocourková, Pavel Fuksa

Soil & Water Res., 2007, 2(2):54-58 | DOI: 10.17221/2117-SWR

The reserve root nutrients influence the overwintering, regrowth, yield, and persistence of alfalfa plants. The total amount of the root reserves is considered more important than their concentration. One of the factors which can affect the reserve content can be the soil compaction. The aim of this study is to clarify the effect of the soil compaction on the reserve root nutrients in relation to the stand density and the amount of the root biomass. In this experiment, the stand density ranged from 28 to 112 plants per m2. The average soil bulk density in the uncompacted and compacted variants was found to be 1.38 and 1.52 g/cm3, respectively. In spring and autumn periods, the root samples were taken from an area of 0.25 m2 (the depth 150 mm) in four replications. The number of plants, the root weight, and the concentrations of starch, saccharose, fructose, and crude protein were assessed in each plot. The total amount of the root reserves was calculated from the determined concentrations and the weights of roots of each sample. A higher soil compaction reduced significantly the stand density, root weight, total amount of all nutrients as well as the starch and crude protein concentrations. The concentration of the soluble non-structural saccharides was identical to or increased over that in the compacted variant. The negative significant effect of a higher soil compaction on the root weight and, consequently, on the total amount of all reserve root nutrients was explained by the changes in the stand density. When the root weight effect was excluded, the compacted variant provided a significantly lower density and crude protein amount and concentration. The significant effect of density on the reserve nutrients was explained by changes in the root weight.

Mycobacterium caprae infection in cattle and pigs on one family farm inCroatia: a case report

Z. Cvetnic, S. Spicic, V. Katalinic-Jankovic, S. Marjanovic, M. Obrovac, M. Benic, M. Mitak, I. Pavlik

Vet Med - Czech, 2006, 51(11):523-531 | DOI: 10.17221/5586-VETMED

An outbreak of tuberculosis among bovines and pigs caused by Mycobacterium caprae is described in this paper. After tuberculin skin tests with bovine purified protein derivates (PPD) six cattle and one sow, own by a small family farm, tested positive whilst three pigs were suspected in 2004. All animals were euthanised and checked for gross pathological lesions. Generalised lesions were found in five cattle and two sows; however one calf and two gilts had lesions that were localised in the submandibular lymph nodes. Mycobacteria were isolated from tissue samples of six cattle and four pigs. Mycobacterial isolates were identified using classical biochemical tests and molecular methods (PCR, GenoType MTBC) as M. caprae. Mycobacterial Interspersed Repetitive Unit (MIRU) typing of isolated mycobacteria showed an identical number of repeats in 12 different loci. Results of the research confirmed the domination of M. caprae among infected cattle in Croatia; however this paper was the first to confirm a case of M. caprae in pigs. The source of the infection was not found.

Intraspecific and interspecific chemosignals in birds: a review

J. Rajchard

Vet Med - Czech, 2007, 52(9):385-391 | DOI: 10.17221/2000-VETMED

This review of chemosignals in birds considers intraspecific oriented chemosignals such as pheromones, interspecific chemosignals, and chemical interactions with parasites. Intraspecific chemosignals are known in some seabirds, especially burrow- or crevice-nesting auklets and petrels that breed in large colonies and are often nocturnal on land. Crested Auklets secrete a distinctive scent closely associated with courtship and important in sexual selection. Individually distinctive odours of petrels allow them to identify their own nest and can have a significant role in social relationships. Substances considered as sex pheromones, diesters of 3-hydroxy fatty acids, are produced by female mallards in their uropygial glands during the mating season. In many species of Charadriiformes during nesting monoester waxes are substituted with mixtures of less volatile diester waxes, less easily detected by mammals searching for nests. The tissues, mainly skin and feather of the New Guinean Passerines of the genus Pitohui and Ifrita contain steroidal alkaloids from the batrachotoxin group probably as a chemical defense. The variation of preen gland secretion in some other Passerines is apparently due to selective pressures caused by ectosymbionts. The auklets' odour, considered as a signal of mate quality, has also a function as ectoparasite repellent: aldehyde constituents of this odour kill and repel ectoparasites. Parasitic nematodes influence grouse digestion and thereby scent emission, making parasitized birds more vulnerable to depredation by mammals. Conversely, scents of some mammalian predators can function as a bird repellent.

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