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Sissoo (Dalbergia sissoo, Roxb.) is a nitrogen fixing leguminous tree species with natural habitat in the lowland region of Nepal called Terai up to an altitude of 1,000 m. For the last few years, this economically important tree species has been dying rapidly in the plantation forests. On the contrary, its status in the natural forest in riverine areas has been unknown yet. The paper compares the nutrient status of natural and healthy sissoo forest with declining plantation sissoo one. It is evident from this study that both stands do not differ very much with respect to their soil and plant nutrients. Therefore it was concluded that the waterlogging of soil was the main factor responsible for the decline of plantation sissoo forest.

This paper deals with large-scale mountain forest decline in the Šumava National Park. The changes in biotic and abiotic properties of forest sites follow the tree layer disintegration. Changed microclimatic conditions such as intensity of irradiance, moisture and temperature of the top holorganic layers together with altered development of ground vegetation could strongly affect the values of microbiological respiration activity and the rates of nitrogen mineralization and nitrification. Soil substrates, built of organic mater, located on stony locations, are endangered by introskeletal erosion. This paper compares these features in pairs of research plots, consisting of dead or cut forest and of living stand. According to the results of this study, higher rates of organic matter decomposition, transformed dynamics of nitrogen and other nutrients and possible nutrient leaching from soil solutions were demonstrated in the forest floor under declined spruce stands. The extent and seriousness of these adverse processes for forest soils are strongly site dependent.

The objective of the trial in the test station was to evaluate productive performance with respect to sire-line No. 101, 102, 103 in C-position for LWs × (LW×L) genotype in pigs. The productive performance as to growth capacity, feeding intake and quantitative traits of slaughter value was examinated for 136 hybrid pigs divided in three groups of offsprings of LWs boar No.101, 102,103. The feeding of all pigs were ad-libitum. On the base of obtained results, one could say that inside the LWs-breed, considerable differences exist between lines, importantly affecting the overall economics of fattening.

The fact that the development of information and communication technologies (ICT) is a key factor of development of individuals, regions, sectors and whole countries is well known at the beginning of the 21st century. The real situation of ICT utilization is very different in particular sections and it fails to reach standards that we would expect. The sphere of the agrarian sector of the Czech Republic is a very good example. The Information and Consulting Centre FEM at the University of Agriculture in Prague (IPC) has been participating on research of the utilization ICT in agriculture for three years. According to the latest data from July 2002, 55% of agrarian enterprises are connected to the Internet, which is much less than in other sectors.

Effects of increasing doses of the herbicidal preparation Sencor 70 WP (metribuzin a.i.) on selected potato varieties were studied in a field and pot experiments using very rapid fluorescence induction (vrFI). Tuber yield, and in pot experiments a tuber number and characteristics of the aboveground biomass were assessed. The curve of rapid induction goes through the O-J-I-P phases. The parameters Fo, Fv/Fp and rFj were measured. Based on changes in the vrFI parameters in comparison with controls, varieties were ranked according to sensitivity to metribuzin in field experiments. Keřkovské rohlíčky and Ukama were the most sensitive varieties and Impala the least sensitive variety. In pot experiments in the growth chamber, significant decrease in tuber weight vs controls was found in sensitive varieties Keřkovské rohlíčky (in 1998, 0.75 kg.ha^-1 Sencor 70 WP decreased tuber weight by 28% and 1.5 kg.ha^-1 by 89%) and Ukama (in 1997, at 1.5 kg.ha^-1 by 35%). Under stable conditions in the growth chamber, there were lower differences in the rFj parameter in these varieties in comparison with controls than in resistant ones. Based on this finding it can be assumed that the sensitivity of varieties can be determined according to rFj changes under stable ambient conditions.

Numerous agricultural and associated ecological effects such as mineral nitrogen fertilising influence the yield of hop (Humulus lupulus L.) cones and its quality. Using a wide spacing of plants (in our case 2.6 × 0.8 m) we want to answer a hypothetical question about an appropriate number of test plants per plot vs. experimental plot area. The aim of this study was to compare the effect of different rates of mineral nitrogen, fertiliser combinations and their nitrogen split application on hop yield evaluated from different plot areas (micro trial: 30 plants per plot; macro trial: 320 plants per plot). Hop yield varied significantly between treatments, plot areas, years and interactions (year × treatment, plot area × treatment) (all at P £ 0.01). Cone yield in a micro trial was higher in all treatments in comparison with yield in a macro trial. In spite of common intensive fertilisation the appropriate fertilising combination and mineral N rate can influence the yield. Target nitrogen rate of160 kg mineral N/ha (at the level from 40.0 to62.5 kg nitrate N/ha in soil depth to0.3 m) and cheaper combination of calcium-ammonium nitrate (50 kg N/ha) at the beginning of vegetation plus urea (110 kg N/ha) for top dressing can be recommended. On plot areas of each size and each year all treatments showed similar trends of fertilising effect on yield. In spite of higher yield in the micro trial and lower coefficient of variation in comparison with the macro trial, the results proved that a risk of incorrect yield analysing in macro trials is very low for field experiments.

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.

The goal of the measurement of the tractor ZTS 164 45 equipped with digital electrohydraulical control EHR-D BOSCH during ploughing with ploughs KUHN (4 bottoms) and 5 PHX 35 (5 bottoms) was to obtain time dependent states of pressure in the hydraulic system of the three point hitch of tractor. From the point of view of comparison of obtained results testing conditions were determinated with respect to physical and mechanical properties of soil such as soil volume mass, soil humidity, penetration resistance and shear resistance of soil. Beyond these measurements also measurements of operation parameters as a ploughing depth, ploughing width, working speed and fuel consumption were accomplished. The measured results of physical and mechanical properties of soil show big content of loam elements and stones in the soil. Simultaneously the measured results of the operation parameters of the ploughing sets confirmed that the ploughs KUHN and 5 PHX 35 are suitable for tractor ZTS 164 45. Based on the measured results there is a possibility to infer following conclusions: Control system of the three point hitch offers a reliable function. Hydraulic circuit is equipped by an improper distributor which causes pressure peaks which are corres-ponding with safety valve adjustment. Hydraulic circuit has a low conductive resistance. Loading of tractor body is higher when using mounted plough than with semi mounted plough.

Vegetable juices processed by lactic acid fermentation bring about a change in the beverage assortment for their high nutritive value, high content of vitamins and minerals. Starter cultures of the genus Lactobacillus are added into juices to achieve their desirable properties. This review describes the manufacture of lactic acid fermented vegetable juices and beneficial effects of the lactic acid bacteria (mainly antimicrobial and anticancer effects). A separate part of research is devoted to nutrition aspects of lactic acid fermentation and to the occurrence of biogenic amines in lactic acid fermented vegetables and vegetable juices.

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.

In vitro propagation of Tilia platyphyllos Scop. has been achieved by axillary shoot proliferation and somatic embryo-genesis. The influence of tree age, explant source, genotype, and phytohormones on micropropagation of juvenile and mature trees of Tilia platyphyllos has been investigated. Nodal segments and shoot tips were used as initial explants for axillary shoot proliferation. Low concentration of cytokinin (BA, BPA, TDZ) plus auxin (IBA) stimulated fast shoot multiplication. Microshootsexcised from proliferating cultures were rooted on low salt medium and produced trees were planted in the field. Embryo-genic tissues were initiated from zygotic embryos cultured on MS medium supplemented with 2,4-D. After transfer of embryogenic tissues with developing embryoids on media lacking 2,4-D and supplemented with low concetration of IBA, the development of somatic embryos was enhanced. Secondary somatic embryogenesis led to the formation of new adventive somatic embryos. Trees produced from somatic embryos were planted in the field and exhibited normal growth and morphology.

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.

In all partial aspects, subsidies can be effectively realised only if the adequate system of information is set up and used both on the level of subsidy suppliers (government) and on the level of subsidy recipients (agricultural organisations). It is essential to control and evaluate the usefulness of providing the support. The GPS technologies are ones of many options how to contribute to this effort. The proceeding rapid progress and upgrade of these technologies, miniaturisation of the apparatus along with the decreasing price and increasing technological efficiency, accuracy and reliability are together granting significant preconditions for their practical utilisation in agriculture. GPS is practically being used in agriculture in the system of precise agriculture and our experts belong among the world-wide recognized specialists in this direction. The GPS utilisation is additionally offered at the allocation of LFAs as well as at marking the places suitable for agro-environmental measures. In combination with the IACS system and its databases and registers, it is functionally and operatively useful at the land control of fulfilling the conditions of support programmes.

Three-year trials were conducted to study germination and emergence of prickly lettuce (Lactuca serriola L.) achenes, increments of shoot dry matter and susceptibility of the weed to selected herbicides. The germination rates of achenes at10°C (92%),20°C (97%) and30°C (95%) did not indicate any significant differences within 20 days from sowing. The highest percentage emergence of prickly lettuce achenes was determined after their sowing into a depth of1 mm. Differences from the variants of sowing onto the soil surface (0 mm), into a depth of 10 and20 mm were significant. There were no differences in the emergence rates from a depth of 10 and20 mm. The highest increments of shoot dry matter were observed when prickly lettuce plants were grown for 4-7 weeks after sowing at20°C. The effect of selected herbicides on prickly lettuce plants treated at the stage of 2-3 true leaves was evaluated on the basis of a change in the content of shoot dry matter. A significant decrease in dry matter against the control was recorded in all variants after herbicide application. The effect (expressed by a lower dry matter content) was significantly higher after the combination amidosulfuron + iodosulfuron-methyl + mefenpyr-diethyl (10 + 2.5 + 25 g/ha) was used than after the application of tribenuron (10.85 g/ha) and picolinafen + cyanazine (120 g + 480 h). The effect of amidosulfuron (22.5 g/ha) was significantly higher than in the variants treated with tribenuron, picloram + clopyralid (16.75 + 66.75 g/ha), clopyralid (90 g/ha) and picolinafen + cyanazine (150 + 600 g/ha). The best effects were produced by herbicides containing amidosulfuron and iodosulfuron as active ingredients.

The distribution of cadmium, lead and zinc in exchangeable, organic, and 2M HNO3-extractable fractions as well as the effect of heavy metal concentrations on soil microflora was investigated. Six sampling transects were chosen in theLitavkaRiveralluvium in 1999-2001. Concentrations of all metals increased with decreasing distance from the source of contamination. The concentrations of Cd and Zn in exchangeable fraction were higher than in organically bound fraction, a reverse trend was found in Pb speciation. All measured parameters of soil microbial activity were affected by heavy metal concentrations. The decrease in CFU was most significant in the case of oligotrophic bacteria and spore-forming bacteria. Significant inhibition of C-biomass occurred in soils highly contaminated by heavy metals. The Cbiomass:Cox ratio decreased with increasing soil pollution. Generally, the values of enzymatic activities were highest in the soil above the source of contamination and they were decreased as approaching the source of contamination. Our results demonstrate that several parameters of microbial activity could be used as good indicators of increasing concentrations of Cd, Pb, and Zn in soil.

This study showed that rooting is strongly affected by natural leaf drop occurring during cutting collection. Observations carried out during sampling showed that cultivars with more than 80% leaf drop had lower rooting percentages than cuttings from cultivars with leaf drop between 44 to 75%, and that generally, the peaks of leaf drop coincide very closely with low rooting. Besides, it was found that there is a relation between Fe and N content in the bark of cuttings and their rooting. The peaks of Fe content coincide with the peaks of rooting. In contrast, the peaks of N content coincide with the lowest percentage of rooting. Overall, there seems to be no clear-cut relation between rooting and contents of P, K, Ca, Mg, Mn and Zn.

The basic principle of the economic reform of state forests of the CzechRepublic after 1990 was to separate ma­nagement in forests from the implementation of production activities. A state enterprise Forests of the Czech Republic with its headquarters in Hradec Králové was charged to manage state forests. From the former 7 enterprises of state forests 78 joint-stock companies have been established that carry out silvicultural and logging activities in state forests and in forests of other owners under the conditions of competition environment and on the basis of contracts. The paper deals with the exact evaluation of partial and present results of the development of forestry economic reform, aimed at the study of the behaviour of transformed and privatised forest joint-stock companies.

The analyses of the activity of cambium and the study of the increment of wood during one growing season of pedunculate oak (Quercus robur L.) under conditions of a floodplain forest is provided. The following parameters were studied: the beginning and end of the cambial activity, differentiation of wood fibres (libriform) and vessels and analysis of the total increment of wood during vegetation in dominant (D), co-dominant (CD) and subdominant (SD) trees in relation to ecological factors of the environment. The course of wood formation corresponds to typical growth curves which are modified by factors of the environment (mean daily temperature, precipitation, soil water supply). The rate of growth is limited by factors of the environment and under the lack of some of them it is reduced resulting in the decrease in the total production of cells. Oak is a species sensitively responding to the period of drought which is particularly manifested in wood increment in subdominant trees. Sufficient supplies of water during spring months accelerate the formation of early wood including differentiation of spring vessels as corroborated by the results. The total formation of wood is dependent not only on the characteristics of the respective growing season but particularly on the social position of trees in the stand.

A new method was proposed that complements the value of active carbon in the soil expressed as hot-water soluble carbon Chws. The method is based on vacuum measurements of biochemical oxygen demand (BOD) of soil suspensions using an Oxi Top Control system manufactured by the WTW Merck Company that is destined for hydrochemical analyses of organically contaminated waters. Measurements will provide BOD values for particular days of incubation; total limit BODt can be determined from these values, and it is possible to calculate the rate constant k1 of mineralization of a decomposable part of soil organic matter. It is typical of soil organic matter (SOM) of a given soil sample and comparable with the BOD5:COD (chemical oxygen demand) ratio that is used to evaluate degradability of water organic contamination in hydrochemical analytics.

Results of scoring the resistance of 35 selected spring barley varieties to powdery mildew, exhibiting high powdery mildew severity, in 307 variety trials of the Central Institute for Supervising and Testing in Agriculture were analysed. The varieties can be divided into two groups: the varieties that could not induce any changes in the pathogen population (the varieties with no effective resistance gene and varieties carrying gene mlo) and the varieties possessing major resistance genes [a total of 12 Ml-genes: a1, a3, a6, a7, a9, a12, a13, at, k1, La, g and (Kr)] to which the pathogen population adapted in 1971-2000. The time slope of decreasing resistance of varieties is described. The importance of individual evolutionary forces (mutations, migration, direct selection, indirect selection and recombinations) for the erosion of efficiency of respective major resistance genes and the effects of pathogen adaptation on population complexity and diversity are discussed.

In small-plot field trials conducted in 2000-2002 we studied the effect of fungicides on the yield and selected technological parameters of grain of malt barley and on malt. For the treatment we used Cerelux (active ingredients: fenpropimorph, flusilazole), Amistar (azoxystrobin) and Caramba (metconazole) applied in two stages of stand development (DC 47 and 55). Compared to the untreated control plants the yield grains ranged between 6.9 and 16.5% after the application of fungicides. The application of fungicides increased the proportion of full grains and had a favourable effect on the chemical composition of grain. After the treatment with azoxystrobin the content of N-substances decreased from 11.43 to 11.07% as compared to the controls. The highest starch content of grain was observed after the application of the active ingredient metconazole; the average content ranged between 64.44 and 64.62%. Compared to the controls the highest relative yield of malt starch (124.2-125.2%) was achieved after the application of azoxystrobin or a combination of azoxystrobin and metconazole in the DC 47 stage. The highest average attainable degree of fermentation was 78.57% and was discovered in the untreated control.

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.

During the years of transition to market economy, a variety of farming types has evolved in Slovakia. Corporate farming is still pursued on about 80 per cent of the total agricultural land area, but a gradual increase of individual farms can be observed. A large portion of the registered individual farms is producing both for the market and for the self-supply of households, but the importance of specialised commercial farms has been growing during the recent years. Their share in the total number of registered individual farms can be estimated as 25 per cent and they specialise as a rule on cash crop products. The average production area is 130 hectares, but income differentiation is wide-ranging within this group of farms. The lowest income strata (which represent about 50 per cent of these farms) receive eight times less income, than the highest one - represented by less than 2 per cent of cases.

A vast majority of agricultural land is leased, only a few owners manage their own land. The market with agricultural land falls behind and, together with land lease, it depends on the prosperity of Slovak agriculture. In comparison with the EU countries, the prices of land and land lease in Slovakia are disproportionately low. At present, the Slovak legislation is focused on legal regulation of long-term, i.e. lasting more than ten years, leasing. However, this raises a question whether we should not rather concentrate on the support of the developing market with agricultural land instead.

The paper addresses the first experience with the SAPARD Programme in the Czech Republic. Its theoretical background refers to gradualist and shock approaches in coping with social change. These approaches are connected either with theoretical fundaments of neo-classical economic theories (shock approach and methodological individualism; homo-oeconomicus), or classical sociological theories (institutions, norms and rules, social embeddedness, methodological collectivism and Durkheim's social fact). An empirical section of the paper is based on findings from field work and interviews with the SAPARD shareholders. It shows a sociological analysis of the origin of the SAPARD Plan and compares various measures implemented under the SAPARD Programme to indicate who was the winner (medium-scale businesses and farms understanding the SAPARD as a preparation for EU membership) and loser (and why) in competing for funding related to these measures. Also the issue how the SAPARD projects applicants master their action as for preparing and submitting projects is addressed. The role of social capital in the SAPARD Programme preparation is documented.

A monitoring system for Cameraria ohridella males based on a synthetic sex pheromone was tested in the Czech Republic, Germany, France and Greece. From the obtained data on the insect phenology we concluded that in Central Europe C. ohridella typically has three generations per year. The pheromone monitoring can be used to detect the pest when it appears in uninfested areas and is also suitable to determine population densities.

The phosphorus (P) availability was tested on hydromorphic soils located in theSavavalley. 480 soil profiles covering the area of31 227 hawas analysed in our study. The plant available P was determined by the Ammonium-Lactate method. The P availability in the surface layer (0-30 cm) is very low (up to 5 mg P2O5/100 g of soil) in about 30% of the tested agricultural land (9 440 ha), next 32% (9 897 ha) is in the range of a low P availability (from 5.1 to 10 mg), while only 17% (5 445 ha) has a good or very good P availability (above 20 mg). Especially high frequency of low P availability was found in vertic gley, amphygley and hypogley soils (total8 680 haor 28% of tested agricultural land).

Approach to the problems of sugar-beet tubers surface damage dependence on harvesting technology. Investigation of sugar-beet tubers damage when falling on wood and iron surfaces and in the next case tuber damage caused by their fall on the tuber heap. Research of damage rate dependence on the fall height. Evaluation of damage rate was carried by the I.I.R.B. method (method used by all sugar-beet growing countries of Western Europe). The results refer that no considerable differences in damage rate after the fall on the wood or iron bottoms have been ascertained. The height of 1.5 m can be considered in all cases as the limit value of the tubers fall, when share of heavily damaged tubers reached acceptable values of 10-15%, but that the share increases significantly at higher falling height. The lifting bodies construction requires also a knowledge of dependence between root depth and force for tuber release from soil in relation to the tuber weight. Medium force needed for tubers lifting ranges from 17 to 27 kp, maximum value 50 kp was found out for tubers of weight above 3 kg.