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Due to increased heavy metal content in Ukrainian soils, purpose of the work was to study relations between presence of heavy metals in soil and their effect on development of phytoviral infection. Experiments were conducted in Nicotiana tabacum - Potato virus X model system. Soluble salts of Cu, Zn and Pb were deposited in soil separately at the limiting concentrations simultaneously with virus infection of plants. Infected plants grown on usual soil showed symptoms of disease on 16 dpi as well as plants grown on soil with metals deposited. Contrary, combined effect of heavy metals and virus infection caused an increase of chlorophyll content comparing with control plants, therefore effect of heavy metals partially compensated the effect of virus infection on experimental plants.

The main focus of the future solutions will be sharing of knowledge. The coming systems will be designed and implemented as advanced distributed interoperable Web services that will share data, information, knowledge and services across Europe. The innovative systems will also implement advanced functionality for mobile data access; location based services, personalised and position sensitive services. The interoperability on the level of data as well as services will be important topic in next years. The WirelessInfo project was one from the first worldwide practical implementation of GIS interoperable standards on mobile platform.

The subject of this paper was to assess the effects of pulverised dolomitic limestone applications on prosperity of Norway spruce (Picea abies L.) plantation and on the soil in extreme ecological conditions of the Jizerské hory Mts. The characteristics such as plant mortality, annual height increment, diameter of root collar (stem base diameter), crown diameter, nutrient analyses and some data from soil analyses are evaluated in this paper. An eleven-year period of observations is summarised. According to the observations and measurements carried out until now, the effect of limestone applications (1 kg per tree) on the spruce plantation prosperity seems to be positive without any serious negative impacts on the soil.

Zinc distribution in the main soil fractions and zinc accumulation in potatoes, maize, wheat and barley after different soil treatments (basic sludge rate, triple sludge rate, NPK, NPK + inorganic Zn) were investigated in a field experiment conducted at five localities of the Czech Republic (Červený Újezd, Hněvčeves, Humpolec, Lukavec, Suchdol) with different soil and climatic conditions. Three soil types were investigated in the experiment: clay-loamy Chernozems, loamy Luvisols, clay-loamy Luvisols and two loamy Cambisols. Sequential analyses provided an overview of soil Zn distribution in the following fractions: exchangeable, Fe-Mn oxide, organic and residual ones. The sludge and inorganic Zn addition supported Zn mobility growth and higher Zn retention in Fe-Mn oxides in all tested soils. The influence of the above-mentioned treatments on higher Zn association with soil organic compounds was not explicitly found. Potatoes, wheat and barley accumulated more Zn after its addition into the soils by sludge and inorganic salt. By contrast, Zn content in maize decreased with higher input of Zn into the soil. The highest Zn concentrations were usually observed in plants grown on both Cambisols.

In 2001, galls were analysed of Pemphigus spyrothecae Pass. taken in one- to three-week intervals from Populus nigra and P. nigra var. italica at 4 localities in Brno. Fundatrices matured in the first half of June and during the first half of summer produced about 50 offsprings. Virgines produced about 10 offsprings which grew up in winged sexuparae. The winged individuals started to occur in galls from the beginning of August. In galls with intact development, on average 500 aphids developed. Galls with intact development on P. nigra var. italica reached larger average dimensions and contained at least by 4% more aphids than galls on P. nigra. About 5% of fundatrices died already in the 1st instar and other 3 to 6% in higher instars by the beginning of reproduction. At localities under investigation, 7.5 to 39.0% of galls on P. nigra and 3.9 to 13.7% of galls on P. nigra var. italica were occupied by the fly Leucopis puncticornis Meig. (Chamaemyiidae). About 24.3 to 32.2% of galls on P. nigra and 23.3 to 49.3% of galls on P. nigra var. italica were occupied by the bug Anthocoris minki Dohrn (Anthocoridae). Hover flies Heringia heringi (Zett.) and Pipiza festiva Meig. (Syrphidae) killing aphids in 3.8 to 30.4% of galls on P. nigra and 6.5 to 6.8% of galls on P. nigra var. italica were an important regulator. In August (i.e. at the beginning of the formation of winged sexuparae), the majority of galls opened through primary slit-shaped or oval emergence holes. A part (7.8 to 19.5%) of galls with so far intact development, however, remained closed and all aphids contained in them died. Diseases (particularly mycoses) often participated in the accelerated dying of aphids. The effect of mortality factors on the gall size differentiation was evaluated in details. The galls do not cause any leaf area reduction. In the case of mass outbreak, they decrease decorativeness of poplars in street alleys. In August and September, liquid excrements fall out from the galls (honeydew) polluting the environment in villages and housing estates.

Two methods were developed and tested for the measurement of the mowing machine material feed rate (based on the conditioner power input measured by a torque-meter, and/or on the material change in momentum measured by a curved impact plate). The measurements carried out in the year 2001 proved that a very good linear relationship existed between the conditioner power input, output frequency of the apparatus measuring the impact force by means of the impact plate, and the material feed rate through the mowing machine. The calculated R-Squared values were about 0.95. In the year 2002, the impacts of material and condition (parameters) changes on the mowing machine material feed rate measurement accuracy were measured under laboratory conditions. It was evident from the statistical evaluation that changing crop variety, crop maturity, and intensity of conditioning can have a statistically significant influence on the measurement based on the torque-meter. As concerns the impact plate measurement, it was found that it is not possible on the basis of our measurements to determine statistically the influence of the factors tested.

The paper deals with problems of thinnings in a mixed stand (spruce-fir-beech) situated in the sixth altitudinal forest zone. Three of the five investigated plots were tended by free crown thinning for a long time, and two were left without any planned silvicultural treatments as control. Dynamic changes in tree species composition, stand structure, qualitative and quantitative production were evaluated for a period of 30 years. The changes were compared with respect to differences between the plot with long-term silvicultural treatments and the control plots (without treatments).

Yellowing of Norway spruce is a relatively common problem in many regions of the Czech Republic. At some places, it is also connected with forest decline. This unfavourable phenomenon is initiated by several ecological as well as anthropogenic processes. One of the most important is the imbalance of forest stand nutrition. Particular reasons lead to nutrient deficiency, especially deficiency of magnesium. Solution to this undesirable trend is a profound ecological analysis and cause-oriented treatments. Besides decreasing air pollution impacts, fertilisation with deficient nutrients represents a successful treatment in the forest stand management in affected areas. In the area of interest, application of relatively small amounts of appropriate fertiliser (SILVAMIX Mg) led to considerable improvement in the defoliation dynamics and yellowing progress since the first year after application.

Arabidopsis thaliana accessions were inoculated with incompatible isolates of downy mildews, following pre-inoculation with compatible Albugo candida. Three isolates of Hyaloperonospora parasitica subsp. A. thaliana, an isolate of H. parasitica subsp. Brassica oleracea and one Bremia lactucae (lettuce) isolate were included. All downy mildews sporulated on A. thaliana, suggesting A. candida suppresses broad-spectrum downy mildew resistance. The white rust resistance gene, RAC5, is being investigated. The resistance phenotype associated with RAC5 seems not to involve a hypersensitive response. RAC5 has been mapped telomeric of nga106 on chromosome 5, in a region lacking NB-LRR genes, the most common structural class of resistance genes known in A. thaliana.

This paper deals with the recent sissoo (Dalbergia sissoo Roxb.) decline in the plain land (locally called as terai) of Nepal. This study has made an attempt to find the possible causal factor of this decline. The study has made some initiative in this aspect and has made a comparative study of 30 different sissoo forest (both natural and plantation) stands. The symptoms of the sissoo decline were found to be varied. But in most of cases, the top dying of crown was found to be the most prevalent. The top dying starts from the top of the tree and progressively proceeds downwards to the stem. The leaves become yellow. Until now, it has been assumed that only the plantation forests have been affected but this study observed the sissoo decline also in natural forest sites. We analysed various components of physical soil characteristics and we did not find any correlation between the physical soil factors and the sissoo decline. We concluded from this study that the soil is not the sole responsible factor involved in the sissoo decline Furthermore, this paper discusses various aspects of the sissoo decline and possible causal factors concerned. Finally, future management strategies regarding the sissoo management are suggested.

This paper is related to the application of the land policies implemented in France in 2nd half of the 20th century, and their consequences on the economy of the agricultural sector and the operation of the farms. Starting from a framework of historical and institutional analysis, the object of this research is to analyse the economic and institutional determinants of these land policies. In France of small landowners, the existence of the right of ownership is considered as an obstacle for a fast evolution of the structures of farms which are sufficient size to implement technological progress allowing the profits of productivity. The aim of the land policy followed in France since the end of the Second World War was to encourage the development of such farms. The main measures were the statute of the tenant farming, the control of the structures and the control of the land market by the SAFER. This policy is implemented at a departmental level by the representatives of the Farmers Unions and generally supports the access to the land for young farmers or the middle-sized farmers.

A traditional approach to problems of the opening-up of forests has been based primarily on technical and economic aspects. It results particularly from the ground configuration and calculations of minimum costs for logging and transport operations. Optimum density of main forest roads is determined by a minimum value of the summary curve of costs of forest road construction and timber skidding. A new conception from the aspect of integrated forest management taking into account forest functions is based on a standard approach when technical and economic aspects are complemented by the particular functions of the forest. Thus, the technical and economic approach is changed to a technical-economic-environmental conception that will contribute to a reduction in negative effects of the construction of forest road network on the environment.

The level of the usage of information and communication technologies (ICT) has a direct influence on the development and competitiveness of individuals, firms, production sectors, regions and even the whole continents. The availability of ICT, including the Internet, to agricultural enterprises in theCzechRepublicis already very satisfactory. Due to the structure of agricultural enterprises the penetration of Internet technologies in theCzechRepublicis more intensive than in most EU countries. Therefore an urgent issue is the level of the usage of these technologies that is not an issue related to finances anymore but it is a problem related to the knowledge and habits of users and availability of information and services. The project of the portal for the agriculture sector and countryside AGRIS has a significant impact on the level of the usage of Internet information and services in the agriculture sector.

In our previous study of Claviceps purpurea three populations were found: G1 on open localities, G2 from shady or wet habitats and G3 on Spartina stands of coastal salt marshes. The latter two are also chemoraces. In the Czech Republic, isolates of G1 and G2 were found. The ability of four isolates representing these populations to infect and develop sclerotia on different host species (Holcus lanatus, Helictotrichon pubescens, Phalaris arundinacea, Dactylis glomerata, Arrhenatherum elatius, Bromus inermis, Bromus erectus, Elytrigia repens, Avenella flexuosa, Lolium perenne, Poa nemoralis, Poa annua, and different cultivars of Poa pratensis) was studied along with their alkaloid production. P. pratensis and D. glomerata were infected by all the isolates and sclerotia were formed by isolates 207 (G1) and 434 (G2), and on two P. pratensis cultivars even by 481 (G3). Infection ability (formation of sphacelial stage and honeydew) was less host-restricted than formation of mature sclerotia. G2 and G3 strains infected A. flexuosa without sclerotia formation. L. perenne was infected only once by strain 207 (G1) without sclerotia formation. P. annua (natural host of G2), was infected by all isolates, but no sclerotia were formed even with G2 strains. From the two G2 isolates, strain 434 from Dactylis formed sclerotia on five host species, whereas isolate 475 originating from Phragmites stand formed only sphacelia. Composition of alkaloid mixture produced in sclerotia of the same strain from various hosts confirmed that host plant does not influence the type of alkaloids produced, only their ratio.

Following measurements of dead wood (20 to 40 years) at various developmental stages of the life cycle of selected virgin forests of the 1^st to 7^th altitudinal zone the relation of its course was derived. The dynamics and course of dead wood in the life cycle of virgin forests were best represented by a polynomial of the third degree. An analysis confirmed that virgin forests consisting of stable tree species with approximately the same physical age (Boky) showed small differences between maximal increase and decrease in necromass during the whole development cycle. Virgin forests at sites rich in nutrients consisting of several tree species with various physical age had high values of necromass during their whole development cycle. Spruce stands at the upper forest boundary also had a relatively high ratio of necromass at the advanced optimum stage.

Soon after bark-beetle attack as well as after clear cutting, grown-up mountain Norway spruce forest cast the following mass of needles: 50-60 kg of dry matter per tree, or 18-20 tons per hectare, containing 8,800-10,000 kg/ha of carbon, 190 to 250 kg/ha of nitrogen, 13-16 kg/ha of phosphorus, 65-91 kg/ha of calcium, 9-13 kg/ha of magnesium and 56-67 kg/ha of potassium. These values were obtained by application of equations assessing needle mass from measured tree and plot parameters, and from chemical analyses of two types of needle material (from living and dead trees).

The aim of this study was to determine the most sensitive growth stage of common buckwheat to frost temperatures and evaluate differences in frost resistance among varieties. A modified field-laboratory method was utilised for the study on four varieties of common buckwheat. The lethal temperature (LT50) was determined for all variants. The critical time of frost action (Lt50) was determined for the lethal temperature and for the most sensitive growth stage. Buckwheat is most sensitive to frost temperature from the stage of primary leaves to the stage of two secondary leaves. Differences among the growth stages developed with plant hardening during the growth. The lethal temperature of buckwheat was in the range -1.3 to -2.9°C depending on the stage of development and growing conditions. The critical time of frost action (temperature -2°C) was in the range 4.3 to 5.9 hours. Varieties Pyra and Emka were most resistant from chosen varieties.

The development and ultrastructure feature of secondary hyphae of Podosphaera leucotricha were studied using light and electron microscopy. The percentage of development and length of secondary hyphae, differed in compatible and incompatible combinations. In compatible host-parasite combinations, hyphal cells of powdery mildew fungus contained a full complement of fungal organelles. There were differences of hyphal ultrastructure in compatible and incompatible host-parasite combinations, the main one was the appearance of dense material inside the nucleus, in the cytoplasm, and a few mitochondria.

Endogenous content of abscisic acid was studied in a set of two winter cultivars of barleys (Lunet, Cenader), one spring cultivar (Akcent) and five winter cultivars of wheat (Mironovská, Samanta, Šárka, Zdar, Apache) and one spring cultivar (Leguan) in the course of cold hardening of hydroponically grown plants. Freezing tolerance was also determined in all barley and wheat cultivars under study. In none of the barley varieties did cold hardening of plants induce any significant change in abscisic acid content. In wheat plants exposed to cold hardening, the cultivars Apache and Leguan showed a slight transitory increase in abscisic acid content. Abscisic acid content in leaves was very similar in the other wheat cultivars. Neither in barley nor in wheat was the level of freezing tolerance associated with endogenous abscisic acid content or with its transitory changes during cold hardening.

Root growth inhibition and loss of cell viability in barley root cells were induced by Al during germination of barley caryopses on filter paper moistened with 2mM AlCl3. The inhibition of root growth as well as loss of cell viability started on the third day of germination. This time was also needed for induction of Al-induced changes in the composition of cell wall proteins. The accumulation of three salt-extractable polypeptides with relative molecular mass 14, 27, and 29 kDa started 72 h after the beginning of germination of barley caryopses on Al containing filter paper. However, the inhibition of developmentally regulated deposition of three (18, 23 and 28 kDa) salt-extractable CW polypeptides was observed at the same time. The pattern of detergent-extractable CW proteins was not influenced by Al regardless of the duration of Al treatment.

Precise categorisation and permanent and completed evidence of agricultural land are necessary for rational utilisation of land fund in Slovakia. Current complex evaluation information system is the only system of this category in our country and consists of the following parts: (1) land-cartographic information system, (2) evaluation data bank. Evaluation data bank includes data about all evaluated soil-ecological units in basic classification, according to users, cadastral areas and higher units of administrative state division. Evaluation data bank is open system updated, improved and widened constantly. It is important source of information used for calculation of land fund evaluation, calculation of financial damage, calculation of land tax, setting of land rent level, estimate of orientation prices for purchase or sales of agricultural land. Recently the data from evaluation data bank have been used for setting and specification of criteria for classification of agricultural land and subjects into the less-favoured areas in Slovakia.

The presence of protein in the culture medium induced secretion of proteases in the studied filamentous fungi species. Comparative analysis of extracellular proteases expressed in vivo by saprotrophic (Trichoderma harzianum, Penicillium terlikowskii) and pathogenic (Alternaria alternata, Botrytis cinerea, Ulocladium botrytis) filamentous fungi species has been carried out. All isolated enzymes were classified as serine proteases on the basis of inhibitor analysis data. According to substrate specificity and the effect of some inhibitors it is proposed that enzymes from T. harzianum and P. terlikowskii are subtilisin-like proteases and enzymes from A. alternata, B. cinerea, U. botrytis are trypsin-like proteases. This fact is, apparently, one of the main characteristic properties of saprophytic and phytopathogenic fungi species. Participation of extracellular fungal proteases in pathogenesis is discussed.

The influence of an interrupted K fertilisation on different K fractions of the soil, yield formation and K uptake by different crops was investigated in a long-term field experiment on Luvisol derived from loess. Irrespective of the previous K fertilisation, the interruption of K fertilisation resulted in a sharp decline of CAL extractable K. K concentration in the saturation extract as well as HCl extractable K were reduced while K fixation capacity increased within 10 years after omitting K. Omitting K fertilisation decreased yields of sugar beet and potatoes while cereals were not affected, although K uptake of all crops reacted to the differentiated K supply to a different extent.

Rapeseed (Brassica napus L.) is an important alternate oilseed crop in eastern Anatolia, Turkey. No information on plant density for rapeseed is available in this region. Therefore a study was initiated to investigate the effects of spacings between rows and spacings within rows on the yield and agronomic characteristics of two genotypes of spring rapeseed (Tower and Lirawell) in Erzurum, eastern Anatolia, during 1994 and 1995. The effects of spacings between or within rows on the yield and yield components of Tower and Lirawell, two cultivars of Brassica napus L., were studied for 2 years inErzurum,Turkey. Rows were spaced at 15, 30 and45 cm. Spacings within rows were 5, 10 and15 cm. The results of this study suggested that seed yield was significantly affected by spacings between rows but not by spacings within rows, and that rape yields were higher at the narrow (15 cm) row spacing compared to the middle (30 cm) and wider (45 cm) spacings.

The paper deals with statistical analysis of the registered regional unemployment rate in regions and districts of the Czech Republic from 1998 to 2002. Regional unemployment reaches significantly different levels; moreover, within the examined period, differences were increasing: variance between the minimum and the maximum increased approx. from 12% to 20% in the respective districts. By means of cluster analysis, regions are divided into more homogenous groups according to the registered unemployment rate by 31 December 2002. The following districts may be identified as the best ones: Praha-západ (Prague-West), Praha-východ (Prague-East), Praha (Prague) and Benešov; the following as the worst ones: Most and Karviná. Concerning regions, the lowest unemployment level may be identified in Praha (Prague); on the contrary, the highest levels were reached in Ústecký region and Moravskoslezský region. Variability, skewness and peak characteristics were calculated to evaluate the development of regional unemployment distribution. The average rose from 5.63% to 9.94%, the standard deviation rose from 2.53% to 4.15%, the variation coefficient stayed around 0.4. Thus, together with the increase in unemployment level, the absolute variability rose while the relative variability stayed approx. constant. The rate distribution was left-sided and increasing; the peak was only slightly higher than the standard peak. The development trend of the characteristics was evaluated by means of linear functions and higher order polynomials; their seasonal variation is described by seasonal indices differing in the degree of their seasonality and distribution in the course of a year. A correlation matrix demonstrates the relations between the trend of the characteristics and their seasonal indices.

Strawberry anthracnose, caused by Colletotrichum acutatum, is one of the most destructive disease of this crop throughout the world. Assymptomatic stages in the plant have been the aim of this work. Inoculated leaves samples were taken at different times and they were processed for scanner electron microscopy (SEM) and transmission electron microscopy (TEM). Conidial development on both surfaces leaves was determined. The ultrastructural study of fungus penetration into plant cell was characterized by the formation of vesicles over the fungus periphery and is a morphological parameter of the intense membranes traffic, also could be a evidence of a transcriptional activity and enzymatic cell secretion. Differences of symptoms on both surfaces of leaves were observed.

Long-term field experiments conducted under different soil and climate conditions and their databases provide invaluable information and are indispensable means in the study of the productivity and sustainability of the soil management systems. We evaluated the results of the dry matter yields of the main products obtained with four variants of organic and mineral fertilisation in three long-term field experiments established in 1955. The experiments differed in the cultivated crops. The period of evaluation was 12 and 16 years (1985-2000), respectively. The productivity of nine-year crop rotation was lower with the fertilised variants than that with the alternative growing of spring wheat and sugar beets. The dry matter yields on the Nil variants, however, were higher in the crop rotation than in the alternate sugar beet and spring wheat growing, apparently due to the symbiotic nitrogen fixation. The dry matter yields of sugar beet and mainly of spring wheat declined in almost all variants of fertilisation in the alternate sugar beet and spring wheat growing, over the evaluated time period. In spite of the relatively high dry matter production, the declining yields indicated a lower sustainability of the alternate cropping system. Both organic and mineral fertilisation increased the production of the cultivated crops. The differences in the average dry matter yields were statistically significant. Both organic and mineral fertilisation enhanced significantly the N-uptake by the cultivated crops. The effectivity of nitrogen input was the highest with the alternate cropping of sugar beet and spring wheat indicating that it was more demanding for the external N-input and thus less sustainable than nine-year crop rotation.

Extensive forest areas were ameliorated by large-scale liming in the last years in order to prevent proceeding acidification and degradation of forest soils. The hitherto knowledge of liming effects on the function of forest soils still appears insufficient for an unambiguous evaluation. Sorption properties of soils and acidity are favourably affected by liming and the favourable effect is usually manifested in the layer of forest floor humus and in mineral soil within ten years. Reduction of soil acidity stimulates development of a bacterial component of microflora, soil edaphon, and good prerequisites are formed for a release of nutrients from soil organic matter. Improvement of some physical parameters of soils and negative effect of liming on the depth of rooting in spruce, availability of nutrients at some sites and in connection with mechanical soil preparation were also described. A key point of liming effect on forest soils is nitrogen dynamics. Mineralization of nitrogen is stimulated at nitrogen-rich sites with C/N < 30. Nitrogen-limited sites show nitrogen mineralization inhibited by liming with signs of pronounced deficiency in spruce nutrition. A positive effect of liming on nutrition with bases is generally accompanied by an adverse influence on N dynamics in acidic soils under spruce monocultures. Therefore it is possible to state that liming induces relatively marked changes in the soil but the actual growth response of woody species cannot be derived only from these changes.

Present study focuses on making best possible use of male gametophytic generation in carnation breeding program. Exploration of pollen population revealed the existence of variability in terms of pollen morphology and histochemical content among as well as within varieties and species of Dianthus caryophyllus and D. chinensis sufficient to make selection. Pollen grain size and histochemical content were found to be associated with germination capacity and pollen tube growth rate. In addition, pollen germination capacity and elongation of pollen tube in response to presence of culture filtrate from F. oxysporum. f.sp. dianthi causal organism of fusarium wilt in carnation was found to be governed by pollen grain size and histochemical content of pollen grains. Entire result suggests the possibility of selecting the desired pollen grains from a pollen population and possibility of attempting selective pollination in carnation breeding program.