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Relations between the level of milk yield and the economic results of dairy cows breeding were analysed on the base of operational and economic data received from 135 agricultural enterprises. The analysis was aiming at the optimization of milk production expressed by means of the cost function. By evaluating the above-mentioned relations, there was recorded a tendency of the faster growth of milk yield compared to the costs for market milk for one feeding day of a dairy cow. On the base of the expense function, there was expressed the maximum profit for a litre of market milk, the maximum profit for a dairy cow per year and the interval of profitability of milk production in 2000.

An outline of past achievements in plant pathology in the CR and main recent problems of Czech plant pathologists are given. A description of the present state in plant pathology in the CR is preceded by data on the structure of CR, on its agriculture, research and development. The outstanding feature of the Czech agriculture is large-scale production. However, the CR still lags behind the EU in yields per hectare. Compared with the EU member states, the CR devotes less money (less then 0.7% of GDP) to research and development (R&D). The trend of state subsidies to R&D in the agriculture sector in current prices is stagnant. It represents an actual decline in the fixed prices. In the Czech Republic, approximately six hundreds persons are professionally engaged in plant health. It represents 6 professionals per 100 hundreds citizens in the CR. Around 160 persons deal with the research and/or teaching of plant pathology. Public service in the field of plant health (advisory work, extension or outreach activities) is one of the weak links in the system of plant health care in the CR. The reason is the lack of commitment for this field of plant health care activity together with absence of sufficient financial support. Minimum requirements for education should be set on advisors and provider of services in the field of plant health at the EU level. In the CR, there exists still some gap in scientific expertise of nematology and integrated pest management. The Czech Lands are proud of the role of some Bohemian and Moravian scientists who have been prominent in the development of plant pathology and related disciplines. These include: AUGUSTUS CARL JOSEPH CORDA and FRANTIŠEK BUBÁK in mycology, GREGOR JOHANN MENDEL in genetics, FRANTIŠEK KRÁL in bacteriology, BOHUMIL NĚMEC and EDUARD BAUDYŠ in plant pathology.

Isolates of Fusarium oxysporum f.sp. ciceri from chickpea (Cicer arietnum L.) can be characterized as races and wilt and yellowing pathotypes by pathogenicity tests on varieties of differentials chickpea. This study shows that, DNA bands generated by RAPD-PCR can be used to assign Fusarium oxysporum f.sp. ciceri isolates to pathotype and pathogenic race.

Small G-proteins (RAC and RHO) are known to be involved in regulation of superoxide (O₂^*-) production and the assembly of actin fibres. These processes are known to be crucial for accessibility and inaccessibility of barley cells to the biotrophic fungus Blumeria graminis f.sp. hordei (Bgh). Using a candidate RT-PCR approach six Rac-related cDNA-clones were isolated from barley. The transient knock-down of RacB led to a remarkably lower penetration efficiency of Bgh into susceptible barley lines (Mlo/Ror1). Surprisingly the inhibition of RacB expression had no effect in the double mutant line A89 (mlo5/ror1). This led us to the assumption that the RacB-dsRNA effect is dependent on functional ROR1 (such as mlo5-mediated resistance). Vice versa, overexpression of constitutive active RACB-V15 in the susceptible line Pallas resulted in hypersusceptibility to Bgh. Thus, we conclude that RACB is a signal transduction protein functional in the accessibility of epidermal barley cells to Bgh.

The antifungal activity of water extracts of dried leaves of folded blackberry (Rubus plicatus W. et N.), walnut (Juglans regia L.), black currant (Ribes nigrum L.), and aspen (Populus tremula L.) was assessed in the in vitro experiment. The tested fungi were Alternaria alternata, Botrytis cinerea, Rhizoctonia solani, Fusarium culmorum, F. oxysporum and F. solani. It was found that all tested extracts inhibited the development of A. alternaria and F. oxysporum, whereas the strongest inhibiting effect was exhibited by extracts of aspen (A. alternata and F. oxysporum), black current (A. alternata) and folded blackberry (F. oxysporum). The tested extracts had no effect on B. cinerea.

The fertilising experiment was set up in 1968 on the mountain meadow (720 m a.s.l.) in Czarny Potok near Krynica (20°8' E, 49°4' N). The experiment was conducted on the acid Cambi soil and comprised objects fertilised with two nitrogen forms and two doses against the background of PK fertilisation, the untreated object, and plots with unilateral P and N fertilisation. The paper concerns 30 years of investigations (1968-1997) of the effect of different NPK fertilisation on the dynamic of yields and the meadow sward quality against a background of the same treatments. The dynamic of the botanical composition was presented as well as the dynamic of the grassland yield potential with systematic mineral fertilisation and liming. The application of nitrogen fertilisation with the rate of 90 N.ha^-1 + PK under mountain conditions and systematic liming of the meadow enables to maintain or increase production over the long period, to decrease the production risk and to prevent degradation of the environment and natural resources.

The influence of long-term regular mineral fertilization on the soil environment considering the total sulphur and the sulphur balance in the habitat of the permanent mountain meadow was investigated. The experimental field (set up in 1968) is situated at Czarny Potok (20°8' E, 49°4' N) in the central part of the Polish Carpathian. With completed annual NPK fertilisation 1.8 kg S/ha was introduced into the soil. The highest sulphur amount was found in the 0-10 cm horizon and this value slightly exceeded the content considered as natural. The sulphur content in the sward from Czarny Potok was lower than the mean sulphur content calculated in Poland for grasses (0.21% S). In the case of full NPK fertilisation the amount of removed sulphur ranged from 11.4 to 14.0 kg S/ha. The mean sulphur leaching into the soil profile from surface of 1 ha can be estimated from 1.1 to 3.7 kg S/ha.

The objectives of this study are to determine the relationship between crown characteristics and the radial increment of beech (Fagus sylvatica L.) and to specify the characteristics of beech trees with the radial increment above the average in the Świętokrzyski National Park. The following relationships have been found: the radial increment of beech increases as the degree of the freedom of the light part of the crown from neighbouring trees increases, and the increase in the relative crown length causes a significant increase in the radial increment. Most of the best growing beech trees are characterized by the light part of the crown confined in an area of up to about 55%, and the relative crown length spanning the range of 55% (trees 61 to 80 years of age at b.h.) to 76% (trees 21 to 40 years of age at b.h).

Physical, chemical and microbiological properties of soils were studied in black walnut (Juglans nigra L.) stands and compared with those in stands of natural species composition, in mixed stands of black walnut with linden and in pure oak stands. The objectives were to consider a possibility of black walnut planting at floodplain sites in the alluvial area of Southern Moravia. The first results did not show any worsening of soil properties and soil production potential. A positive amelioration effect of soil- improving species was proved in black walnut stands.

In identifying perceptions and attitudes relevant to consumer acceptance of goods originating in different countries, it would be extremely helpful for marketers to have a meaningful and consistent measure that they could apply. This study examines to what extent consumer ethnocentrism as measured by the CETSCALE singularly, as well as in concert with selected demographic and psycho-graphic variables, can predict consumers' evaluation of domestic versus foreign produce. The findings indicate that consumer ethnocentrism is a strong and significant predictor of consumer product evaluations. Including the ethnocentrism variable in a set of demographic and psycho-graphic variables significantly improves the predictive ability of the set. Potential applications of the concept include identification of market segments that react more favourably to domestic or foreign produce, developing effective marketing communication strategies, and supporting location decisions for retail outlet sites.

The comparison of Czech and French agriculture results shows a higher intensity, productivity and profitability of French agriculture. There are just small differences in the effectiveness of the production. The Czech agricultural enterprises have been in economic distress for several years and only a low portion of them is able to modernize and increase reproduction. There is also highlighted the importance of the EU Common Agricultural Policy for the development and stabilization of French agriculture.

The incidence of Zucchini yellow mosaic virus (ZYMV) was monitored in the south Moravian region of the Czech Republic during 1997-2001. Crops of gherkin, squash, zucchini and cucumbers were found infected with ZYMV, manifested by symptoms of severe stunting and yellowing with deformed leaves and fruits. Twenty to eighty percent of infected plants were recorded. Six isolates of ZYMV from four localities were differentiated on indicator plants; three of them were maintained as being typical for differences in pathogenicity. Overwintered weed species were tested for the presence of the virus. ZYMV was detected by ELISA in one plant of Tripleurospermum maritimum out of 46 tested, and in two plants of Stellaria media out of 29 tested in 2001. Such tests were repeated in 2002, and ZYMV was detected in three plants of T. maritimum out of 45 tested, in three plants of S. media out of 52, and in two plants of Trifolium repens out of 17 tested. The virus was successfully transmitted from T. maritimum, S. media and T. repens to indicator plants of Cucurbita pepo convar. giromontiina. Back-transmission of ZYMV was proved by ELISA, electron microscopy and symptoms. T. maritimum was found to be a new natural host of ZYMV.

Relationship between initial oospore number of Pythium oligandrum, mode of the mycoparasite application and populationdynamics of Fusarium oxysporum f.sp. dianthi and development of Fusarium wilt of carnation was studied. Mixing ofoospores with peat 10 days before carnation planting resulted in strong inhibition of the pathogen development. Numberof colony forming units of the pathogen decreased at least 3 times. Application of P. oligandrum resulted in suppressionof Fusarium wilt development, especially when the mycoparasite was applied at dose 100 oospore/g of peat.

The quality of eggs is tightly associated with freshness. New possibilities for the determination of egg freshness were studied. The volatile compounds of eggs and their changes during storage were followed. Three methods for extraction of volatiles were compared: dynamic headspace (Purge and Trap), static headspace (Solid Phase of Microextraction - SPME) and extraction according to Likens-Nickerson by simultaneous distillation-extraction (SDE) with diethyl ether as organic solvent. The extracts were analysed by GC/FID. The volatiles in an extract obtained by SDE method were identified by GC-MS. The extract includes aldehydes, alcohols, acids and esters. The volatiles in an extract obtained by SPME and Purge and Trap have not been identified until now. The changes in volatiles during storage of eggs using the above mentioned methods were studied.

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.

The efficiency of leaf rust resistance genes in adult plants was studied on near-isogenic lines of Thatcher carrying known leaf rust resistance genes in the artificially inoculated leaf rust nursery of the Agricultural Research Institute of the Hungarian Academy of Sciences in Martonvásár over a five-year period (1997-2001). Eight of the wheat lines tested (Lr9, Lr19, Lr23, Lr24, Lr25, Lr29, Lr35, Lr37) exhibited little or no infection. Lines carrying genes Lr13, Lr44 and LrB were resistant in two years and those carrying Lr34, Lr38 and LrW in three years, after which they suffered moderate or heavy infection. Three lines (Lr12, Lr17, Lr32) proved to be moderately resistant. The majority of the wheat lines tested became heavily infected.

The conception of these investigations is based on the premise that a way should be found to eliminate, or at least mitigate, the harmful effect of excessive soil acidity without resorting to the massive and costly measures of liming. The main issue addressed in this study is how to increase crop yield by increasing nutrient availability rather than how to neutralize the soil. This as well as our earlier investigations, conducted on pseudogley of mesoelevations, indicate that this can be achieved by the application of special natural amendments (SNA) based on zeolite tuff, under the name Agrarvital (AV), in which clinoptilolite prevails while the remaining part is a mixture of soft lithothamnian limestone and dolomite (SLL+D). These amendments enhance ion exchange in the soil and their activation at a considerably lower pH than it is the case after liming. Fertilizing value of Agrarvital (AV) and lime materials (LM) was evaluated according to the yields achieved and some yield components of the crops grown. The results point to the good fertilizing effect of AV upon yields of winter wheat, maize, soybean and winter barley, equal to or better than the effect of conventional LM applied at several times higher rates.

A model experiment was conducted to compare hand extraction (elutriation) under running water and elutriation using the device Analysette 3, the two methods for estimation of weed seedbank in the soil. Technical parameters have been assessed for efficient operating of the device. We studied the time required for elutriation of soil samples and the time for collecting, counting and identifying the separated seeds. No significant difference in the effect of the used elutriation method on results of qualitative and quantitative estimation of weed seedbank densities has been found at any of the three locations differing in soil texture (silty loam, loam and clay loam soil). The time necessary for elutriation of soil samples was highly significantly shorter if the device was used, by 35.5 to 42.9% depending on soil texture vs. hand elutriation. The shortest time was assessed for silty loam soil. By contrast, the time needed for selecting, counting and identifying seeds was shortest for clay loam soil. This time was 46 and 92% longer for loam and silty loam soil, respectively. These differences were statistically highly significant. Comparing the seedbank in the soil, a significantly lower number of weed seeds as well as species was found on silty loam soil vs. the two locations with heavier soils. Amaranthus retroflexus was a dominating species at all locations, and on silty loam soil also Chenopodium album. Of a total number of 32 weed species detected in our experiment, 28 were annual and only four perennial (Cirsium arvense, Elytrigia repens, Rumex obtusifolius and Sonchus arvensis).

The differentiation between anthropogenic and geogenic loads of the soils by potentially risky elements was observed. The collection of soil horizon samples from 21 localities with different anthropogenic loads (imission fall-outs, floods, historical mining) and geogenic loads (lithogenic, chalcogenic) was composed. The soil characteristics (pH, C_ox), total content of 13 potentially risky elements, content of potentially risky elements in the extract of 2M HNO₃, 1M NH₄NO₃ (mobile forms) and 0.025M EDTA (potentially mobilizable forms) were detected. The solubility as the ratio of total content and the content of risky elements in the other extracts was calculated. The differences between the solubility for each risky element and for each type of the load were determined. It was concluded that the highest solubility was determined in the fluvisols contaminated by the floods and in the soils contaminated by imission fall-outs. Significantly lower solubility of potentially risky elements was determined in the soils with geogenic loads. The efficiency of the used extracts for the differentiation of the soil load was assessed (2M HNO₃, 0.025M EDTA). The types of geogenic loads were characterised in the extent of used soil collection. Geochemically anomalous parent materials and soil types developed on these parent materials were described.

For 17 cultivars of winter wheat (Triticum aestivum L.) different vernalization and photoperiod responses were detected. The effect of photoperiod sensitivity was not significantly changed by vernalization; different vernalization responses were probably due to the presence of multiple alleles at Vrn loci. The delay in heading depended on the vernalization deficit exponentially: y = Parameter (1) + (y0 - Parameter (1)) × EXP (Parameter (2) × (x - x0)). The dependence was shown to be general and significant for the given model in all the studied cultivars. Individual regressions characterised responses of cultivars to a deficit of vernalization treatment. Cluster analysis according to the characterisation obtained (full vernalization requirement, minimum vernalization requirement, insufficient vernalization and parameters of the dependence) showed the relationships between cultivars and enabled their grouping by similar profiles of vernalization, and, possibly, of photoperiod response. In individual cultivars, an attempt was made to use the model to predict performance for some agronomic traits.

Forty two peach-nectarine (Prunus persica [L.] Batsch.) varieties (i.e Spring Time, Precocissima Morettini, Southhaven, Halehaven, Blazing Gold, Cardinal, Gialla Precoce Morettini, Dixired, Fertilia Morettini, Golden Jubilee, Coronet, Red Haven, Red Globe, Cotonia Massima, Morettini 5/14, Peach of Station, Alexander, Early Elberta, Elberta of Middle Season, Beauty of Georgia, J.H. Hale, Late Elberta, Gold Drest, Morettini No. 1, Jerseyland, Desert Gold, Red Cup, Spring Crest, Loring, June Gold, Merril Gem Free, Early Red, Red Skin, Merril Fortyminer, Roubidoux, Fantasia, Sunhaven, Flavour Top, Merril Franciscan, Blake, Fairtime, Fayette) were studied for 12-18 years in three experimental orchards of Peripheral Agricultural Research Station of Rhodes (PARSR). Their degree of adaptation to the soil and climatic conditions of PARSR was evaluated in terms of yield per tree, time of bloom, time of fruit ripening, fruit quality etc. These results have been compared with related experimental data recorded at the Pomology Institute (PI) at Naoussa. The results indicate that: many peach-nectarine varieties with quite high chilling requirements (Loring, Blake) gave satisfactory yield in PARSR, where the mean average of temperatures below 7°C over one decade was found to be 147 hours (range 52-226). Some peach-nectarine varieties in experimental orchards of PARSR ripened more than ten days earlier (Desert Gold, Early Red, Peach of Station, Loring, Merril Gem Free), of others at about the same time (Coronet, Cotonia Massima, Red Skin, Fertilia Morettini, Red Globe) and at others on a later date (Merril Fortyminer, Early Elberta, J.H. Hale, Cardinal, Southhaven) than they would ripen in northern Greece (PI). Similar differences were also found for the time of blooming.

This paper evaluates the development of growing stock, number of trees and diameter distribution of the standing volume in the Opuky locality where conversion to a selection forest has been the aim of management over a long period of time. With respect to species composition, the stand is divided into two plots. The initial condition and development of both plots differed. The favourable initial composition of the stand has gradually deteriorated due to delay in natural regeneration and therefore recruitment of young trees over a long period. The total number of trees on both plots has been low for target diameter of 51 cm. On the other hand, the growing stock has exceeded the model condition. The proportion of broadleaved species in the stand gradually increases, reducing the possibility of conversion to a selection forest in future.

The objectives of this study are to determine a trend of the radial growth at breast height (b.h.) and to compare the radial growth of trees of younger and older generations in the XX century for fir (Abies alba Mill.), beech (Fagus sylvatica L.) and pine (Pinus sylvestris L.) in the Świętokrzyski National Park. In the investigated area fir, 41 to 200-300 years of age at breast height, gradually regenerated its radial growth after a very strong decline during 1971-1990, and most likely the process of vitality reduction and death of its stands of various age is slowly coming to an end. Pine showed a systematic decrease in the radial increment during 1885-1994, and there were no distinct symptoms indicating a change of this unfavourable trend. Beech showed no significant decrease in the radial increment during 1885-1994. In the Świętokrzyski National Park the differences in the radial growth between younger and older generations were noticeable only in the case of beech. The radial growth of trees of different ages was very similar in the case of fir and pine.

What regards the vision of the future relationship of the global and regional liberalisation, two variants are offered. According to the first, multilateralism will go on perpetually around the present trajectory and gradually will, supported by the processes of internationalisation and interdependence, accelerated by the condensing net of trans-national corporations and their activities, suppress regionalism. According to the second, regionalism will, closely connected to multilateralism, spread territorially into the shape of several macro-regions as a transitive stage to the unified liberalised world economy. In both cases, it regards of course the visions of a system and not matter-of-fact type. In the frame of each region, there will further exist different comparative advantages, which will influence the volumes and structure of production and trade, as well as certain specific fields of economic policy. However, that changes nothing of the fact, that namely multilateralism contributes to a considerable extent to reaching a higher equilibrium, adaptability and coherence of the world economy as a whole, even if reaching of this state is connected with considerable, mostly, however, short-time, costs. The contribution characterises globalisation and regionalisation: its contents, types and dimensions, TNC, unequality of the globalised economic development.

The article deals with the preparation of the agricultural business structure for accession into the European agrarian structures in the pre-accession period. Main attention is devoted to the preparation of agrarian management and to changes in the macroeconomic area. From the viewpoint of the information mentioned above, the paper includes the explanation of the agrarian functions in the agrarian sector and prediction of the development of business base in the sectors of agriculture, food processing industry and services. The synthetic part deals with the integration and globalization tendencies in the agricultural and food production.

Ergot, caused by the fungus Claviceps purpurea (Fr.) Tul., belongs to the main constraints in seed production of Kentucky bluegrass (Poa pratensis L.). The level of ergot occurrence depends on the weather conditions during the growing period, harvest year, storage conditions of seed, and post-harvest treatment. The degree of resistance of the grown cultivar plays an important role. Based on greenhouse trials with four different ergot populations (Zubří, Czech Republic; Leutewitz and Munich, Germany; Pullman, Washington, USA) during 3 years, we found pathogenicity to be one of the most important factors. There were significant differences in the amount of ergot bodies formed between the Central European populations (Zubří, Leutewitz) and the American one from Washington State. The degree of pathogenicity has a major impact on the occurrence of ergot sclerotia in seed of Poa pratensis.

The genus Armillaria belongs to basidiomycetes and has been known to induce root rot disease and to cause extensive economic losses to a forest crop. We analysed about 40 isolates of Armillaria collected in Czech Republic by PCR and restriction analysis using gel electrophoresis and ion-exchange HPLC. Restrictase Hinf I was able to discriminate all investigated Armillaria species. The sensitivity and resolution of HPLC method was better than that performed by gel electrophoresis. HPLC was able to detect some heterozygous. The results prove the similarity of the species A. borealis, A. cepistipes, A. gallica, A. ostoyae in difference of A. mellea and A. tabescens.

We characterized the genetic diversity of seventy-three C. lindemuthianum isolates collected from 10 different countries by Amplified Fragment Length Polymorphism (AFLP) analysis. The results of this research highlighted the fact that there is huge variation in the genetic diversity between isolates from different countries. The molecular profile of the isolates showed correlation with geographic origin of the isolates.