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The objective of this study was an improvement on oat identification procedure for laboratory applications, and the comparison of albumin-globulin and avenin protein patterns in five hulled and naked oat cultivars: Abel (CZ) and Izák (CZ) - naked oats, Auron (CZ), Edmund (D) and Expander (D) - hulled oats. The last object of this study was the authenticity verification of standardly prepared meal samples with various proportions of admixture. It was confirmed that avenins, characterised under SDS-PAGE conditions, are reliable implements for the identification of oat cultivars. It was found that oat grain contains, on the basis of Osborne fractionation, another significant protein fraction - glutelins. The question of the protein fraction analysis that was used for the admixture identification stays still open. In sufficiently different cultivars, the certainty of the admixture detection in meal samples may be high. Nevertheless, in other cases (higher cultivar similarity) it will be necessary to use some other, more sensitive techniques.

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.

In the area of southern Poland 33 pine stands growing at the altitudes from 350 to 1,200 m above sea level in the Carpathian and Sudeten Mountains were selected as the object of studies. Thirty-three site chronologies of tree-rings, representing each site were constructed. A decrease in the similarity of dendrochronological signal chronologies occurred with the growing distance between the sites. Correlation and convergence analysis and the Principal Components Analysis permitted the differentiation of two chronology groups: the Western (Sudeten) and the Eastern (Carpathian) ones. On the basis of the site chronologies regional chronologies for the Carpathian and Sudeten Mts. were constructed. The investigated pines from the two regions manifested great sensitivity to winter frost and in summer to the deficiency of heat and water. The chronologies were strongly integrated by the pattern of air temperatures, being differentiated by the pluvial conditions.

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.

Agriculture is a sector in Latvia which plays an important role in the country's economy and the same time performs a significant social, environmental and ethno-cultural function. Latvia has favourable conditions for the development of organic agriculture. The aim of land reform is to reorganise legal, social and economic relationships of land property and land use to facilitate the development of infrastructure, land protection and rational land use according to the interests of society. In Latvia, the land reform is practically carried out in three directions - restitution of real estate rights, privatisation of real property and compensation for previous real estate. At the moment, the main and urgent goal concerns strengthening of the results of land reform. It means that all the information on real estates (land and buildings), uses and area of lease obtained during the previous course of land reform must be reflected into the real property cadastre.

The project of the AGRIS WWW portal proposes from its very beginning to establish a platform for providing information from the spheres of agriculture, food industry, forestry and from other areas related to the countryside. The main objective is to provide access to the already existing information sources, to run its own news service and to help with publishing of the information to the subjects that have limited conditions for electronic (Internet) presentation. This leads to creating of a complex block of information from the industry. This block is to serve for improving availability of the respective information for managers, public administration, students, teachers, consultants and other users.

The effect of chemical weed control with reduced herbicide rates (pre-em., pre-em. + post-em., post-em.) on weed population density and maize yield was compared in three tillage systems (mouldboard, chisel, disk harrowing) for lessive pseudogleyic soil in north-eastern Croatia(1997-1999). These main weeds were present in all tillage variants: Echinochloa crus-galli (L.) PB., Chenopodium album L., Ambrosia artemisiifolia L., Polygonum lapathifolium L., Equisetum arvense L. and Calystegia sepium (L.) R.Br. The density of all weeds was significantly affected by tillage and it ranged from 204 plants on untreated plots with mouldboard to 372 and 421 plants per m2 with chisel ploughing and disk harrowing, respectively. In comparison with standard tank-mixture of atrazine herbicide (metolachlor 50% & atrazine 20%) at the recommended rate, atrazine-free herbicide combinations (metolachlor + 50% prosulfuron & 30% primisulfuron-methyl; sulcotrione + bromoxynil; thifensulfuron-methyl + nicosulfuron) showed a similar total efficacy of weed control (95-96%). Band spraying with standard treatment at a half-recommended rate combined with mechanical weed control brought a satisfactory total weed reduction (83-87%). The weed control methods had no effects on maize yields that were significantly affected by year and tillage. Compared to the highest yield with mouldboard ploughing (10.2 t/ha), average percent yield depressions with chisel ploughing and disk harrowing were 10 and 22%, respectively.

Development of powdery mildew and leaf rust epidemics was examined on three winter wheat cultivars with different predispositions to powdery mildew in three-year experiments. The progress of powdery mildew and leaf rust on the same cultivar was conditioned by its dissimilar susceptibility to the respective disease. Fit temperature played an important role at the beginning of the particular disease and during its progress. Significant differences in the disease severity of powdery mildew and leaf rust were recorded on single leaves. Disease severity of leaf rust was higher on upper leaves while disease severity of powdery mildew was higher on lower leaves.

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.

One of the basic demands for milking machines is to maintain a constant vacuum level if air consumption by milking machine is changed. The author designed a device with reducing valve for vacuum level regulation and a simultaneous vacuum pump control enabling electric power to be reduced. The paper deals with a comparison of the operation of standard control valves with the newly designed device used for vacuum regulation from the viewpoint of dynamic properties. When measuring vacuum stability by applying various regulation methods and a subsequent statistical evaluation of the results obtained it was proven that the function of the newly designed regulating device was comparable with the best reducing valves used so far.

The effect of phenylurea with reported cytokinin-like activities on seed germination, seedling growth, activities of antioxidant enzymes, polyphenol, peroxidase, indoleacetic acid oxidase, and total phenolic compounds, flavonoids was investigated in stressed barley seedlings. The application of phenylurea decreases the activity of peroxidase, indoleacetic acid oxidase and increases the activity of polyphenol oxidase with decrease in total phenolic compounds and flavonoids and consequent increase in growth rate. Saline (NaCl) stress in barley seedlings causes an increase in total phenolic compounds, flavonoids and enhancement of peroxidase and indoleacetic acid oxidase activities and consequent decrease in growth rate. The adverse effect of salt stress on germination, antioxidant enzymes, phenolic compounds, flavonoids can partially be rectified by phenylurea.

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).

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.

The phenophase course in a group of 20 apricot genotypes was evaluated in South Moravian conditions in Lednice, Czech Republic, from 1994 to 1999. The evaluated phases were as follows: "beginning of blossoming", "beginning of picking maturity" and "end of picking maturity". The aim was to evaluate the variability of these phenophases and their relationships. The amplitude of the phenophase "beginning of blossoming" did not exceed 9 days. The amplitude of phenophases between the different years was about three times higher than the average amplitude between the genotypes. The average amplitude of the factor "beginning of picking maturity" observed in all genotypes was 39 days, but a comparison between the years showed that the largest amplitude for a given genotype was only 16 days. No statistical correlation was found between the phenophases "beginning of blossoming" and "beginning of picking maturity" in any of the six observed years. The genotypes whose maturity occurs at the beginning or at the end of picking season showed higher year to year variability of the phenophase "beginning of picking maturity" than the genotypes maturing in the middle of the season. The rate of fruit development from blossoming to picking was considerably different depending on the apricot genotype. The number of days between the beginning of blossoming and the beginning of picking maturity was characteristic of each genotype. The variability of this interval for the six years was very low and the value of variation coefficients did not exceed 10%. This amplitude observed in the control variety Velkopavlovická LE-6/2 was on average 100 days. A very high statistically significant correlation (r = 0.996⁺⁺) was observed between the intervals from the "beginning of blossoming" to the "beginning of picking maturity" and to the "end of picking maturity".

The mycoflora was investigated under the conditions of climax spruce stands in the Krkonoše Mountains in relation to wood decomposition. The areas under observation have been affected more or less by air pollution since the eighties. The average mass of deadwood found on the plots is 124 m³ per ha - the mass of fallen trunks is about 32 m3 per ha, mean value from total average. About 128 species of macrofungi were identified that besides others included 43 species of wood-decaying fungi. Also 54 mycorrhizal species were identified. Among the mycorrhizal fungi about 10 species were dominant, such as Laccaria laccata (Scop.: Fr.) Cooke, Lactarius helvus Fr., Lactarius mitissimus Fr., Lactarius rufus (Scop.) Fr., Russula emetica (Schaeff.: Fr.) Pers. and Russula ochroleuca Pers. etc. Concerning the volume of decomposed wood on monitored plots in climax spruce stands, the prevalent wood-decaying fungi are brown rot fungi. The proportion of brown rot fungi in wood decomposition is 60-95% of deadwood mass on the plots of climax spruce stands. A dominant species is Fomitopsis pinicola (Sw.: Fr.) P. Karst. causing the brown rot. Concerning the group of white rot fungi, the most important is Stereum sanguinolentum (Alb. & Schw.: Fr.) Fr., participating by 17% in wood decomposition on plots damaged by deer.

The aim of the experiment in test station was to evaluate productive performance with respect to feeding-technologies through the test for LWs × (LW×L) genotype in pigs. The productive performance as growth capacity, feeding intake and quantitative traits of slaughter value was examined for 144 hybrid pigs divided in two identical groups, where the 1st group was fed ad-libitum and the 2nd one semi-ad-libitum. On the base of profit formula, the ad-libitum system of feeding in pigs is better in all economic features.

The economic importance of agricultural sector in Slovakia declined during transition period. There are several reasons for this: declining terms of agricultural trade, extreme weather, transformation of agricultural sector, unclear property rights in transition period, short-run privatization distortions, transformation of up and downstream sectors, world market fluctuation, decline of real wages, low stability of agricultural policy and other. The development in economic market was paralleled by activity in political market. After initial liberalization, agricultural protection subsequently increased. The EU accession influences both levels of protection as well as instruments of agricultural policy.

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.

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.

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.

A polyfactorial field trial with alfalfa (Medicago sativa L.) cv. Palava, Jarka and Vlasta was established in Červený Újezd (altitude405 m a.s.l., average year precipitation493 mm per year, average year temperature 7.6°C, clay loam orthic luvisol) in the spring with a companion crop (spring wheat) in rows of a space of125 mm, sowing rate 16 kg/ha of germinable seeds in the year 1998. The stands were cut 3 times per year, the control variant was left without a treatment, the rest were cultivated with a spike or a vibration harrow before the beginning of the vegetation season and after the first cut. The numbers of plants and stems per m2 and dry mass yields were measured. The results were evaluated by four-factor analysis of variance Anova and by regression analysis. The harrowing of the stands resulted in a significantly lower amount of plants per m2 in the end of the fourth year by 23-29%, on average a lower number of stems per m2 (by 13% using double cultivation per year with the vibration harrow). The dry mass yield was significantly influenced only with cv. Jarka (by 5-11% higher in the cultivated fields). The moderately or relatively strong relationship between the plants amount and the time was exponential.

In birch (Betula pendula Roth) stands of the Děčín sandstone uplands (northern Bohemia) 55 species of leafhoppers were captured using photoeclectors, ground traps and shaking down onto sheets (23,855 specimens of larvae and imagoes). The dominant representatives of the grass and herb undergrowth in birch stands are Jassargus allobrogicus, Anoscopus flavostriatus, Neophilaenus lineatus, Hyledelphax elegantula, Diplocolenus bohemani, Streptanus brevipennis, Macustus grisescens, Planaphrodes bifasciata and Cercopis vulnerata. A heavy abundance of the dominant Oncopis flavicollis and the less abundant O. tristis, weakens birch growth due to the leaf-sucking activities of the insects.

The present study documents the effects of green alder [Alnus alnobetula (Ehrh.) C. Koch] on the uppermost forest soil layers in mountain areas, respectively in the summit part of the Jizerské hory Mts. Pedochemical characteristics of holorganic horizons in stands of this species, established in 1992 on a clear-cut caused by air pollution, were compared to the status of soils in stands of bog pine (Pinus rotundata Link.). Extreme site conditions and young age of both stand types resulted in low effects on the humus forms in the first decade. Despite of this, enrichment in total nitrogen content and tendency to acidification due to nitrate leaching were obvious and statistically significant in green alder stands.

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.

One of the conditions of accession of Slovakia into the European Union is the existence of a developed land market. At present, the official land price is mostly used in the evaluation of agricultural land. The price was calculated on the basis of normative production and normative costs required to achieve such production. As the land market gradually develops, market prices come into being; reflecting the effect of real market forces. With the full-fledged market prices, the task of official prices will be just an informative one. The land market prices will gradually assume all the tasks of the current official prices of the agricultural land.

Data collection, data processing, data presentation and data application in the System of Precision farming guarantee a success of this system in the market. Difficulties of technologies, which are currently and continually involved in this system, argue against its practical using by farmers. In this case, service company wants to create a suitable environment not only for data collection, but also for the high quality of the information distribution to customers. One of such tools is the MapServer placed on Internet web sites.

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.