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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.

The post-eradication incidence of bovine tuberculosis in seven Central European Countries (Bosnia and Herzegovina, Croatia, Czech Republic, Hungary, Poland, Slovakia and Slovenia) was studied between 1990 and 1999. The majority of cattle to the age of 24 months were screened by tuberculin skin test on annual basis. Tuberculous lesions observed during meat inspection at abattoirs were further laboratory examined by direct microscopy, cultivation and histology for the presence of mycobacteria. Data describing the incidence of the disease in animals for the whole period were obtained from all countries except Bosnia and Herzegovina, where data were obtained after the year 1995. Between the years 1990 and 1999, bovine tuberculosis was diagnosed in a total of 1 084 cattle herds. Nine hundred and seventy five (89.9%) outbreaks of the disease were reported in small herds (10 cows) and 109 (10.1%) outbreaks in large cattle herds (>10 cows). The last outbreak of bovine tuberculosis in cattle was diagnosed in Slovakia, Slovenia, the Czech Republic, Croatia and Bosnia and Herzegovina in 1993, 1993, 1995, 1999 and 1999, respectively. Bovine tuberculosis was diagnosed under proper quarantine in Slovenia in 37 fattening bulls imported from two European countries before animals were introduced to the targeting farms.

The paper presents a method for the derivation of total timber production and of increments in value units, particularly in net financial yield for spruce stands damaged by crown defoliation after their dieback. The value production was derived by means of value growth models of undamaged stands and models for the adjustment of volume and qualitative production of damaged and died stands. Changes in timber quality after tree drying and changes in the production of damaged stands compared with undamaged ones are illustrated in tables and graphs. The changes are expressed by means of the indexes of total mean increment and total current increment. They depend mainly on the degree of stand damage expressed by crown defoliation, age and yield class of stand, the age of stand when the damage started and duration of damage. The value of damaged stands after their dieback is lover minimally by 50% than before their dieback. It is caused mainly by deteriorated quality of timber from dead trees in stand.

Chrysopids and Hemerobiids were studied using Malaise traps in young spruce forests in the eastern part of the Czech Republic. A total of 12 species were found. The most abundant species were eurytopic Chrysopa carnea, Chrysopa perla, Hemerobius humulinus and Hemerobius pini associated with conifers. The seasonal flight activity of these species is discussed.

Many factors, most notably climate, soil, genotype and fertilising, can influence barley grain composition and its nutritive value. The aim of the research was to evaluate the impact of mineral N rate in different management systems in the static long-term experiment with three years field rotation of grain maize, wheat and barley on the chemical composition of winter barley and its nutritive value for ruminants. Crude protein content and metabolizable crude protein content were increasing with increased mineral N rates. Higher yield meant lower crude protein and metabolizable crude protein content in all mineral N rates. The average crude protein content of barley grain, presented in DLG tables (1997), which is 12.4%, was in MM and SM reached by fertilising rate 110 kg N/ha. A significant impact of mineral N fertilising on crude ash, ether extract and crude fibre content could not be confirmed, nitrogen-free extract content was decreasing with increased mineral N rates. A significant impact of the management system on the Weende analysis parameters, net energy for lactation, metabolizable energy and metabolizable crude protein could not be confirmed. At both analyses a significant impact of the season was confirmed on crude protein content and nitrogen-free extract content. Although the protein content was increasing with increased mineral N rate from 9.2-14.2% (for 35%) ME content and NEL content did not significantly differ considering mineral N rate; ME/ha and NEL/ha increasing with increased mineral N rates was the result of the yield increasing with increased mineral N rates.

Plum pox virus (PPV) is widely distributed in plums and myrobalans in western, central and easternBohemia, in north-western, central and north-easternMoravia of theCzechRepublic. In southernBohemia and partly also in southernMoravia there is only a low and sporadic incidence. Naturally growing plums and myrobalans, and plums growing along roads were found to be the main sources and reservoirs of PPV infection. This high incidence in naturally growing plum and myrobalan trees makes it impossible to grow plum cultivars that are susceptible to PPV; only resistant cultivars can be grown in this country. In blackthorns the occurrence of PPV is limited to the regions with high and long-term presence of the virus. Therefore, we can conclude that blackthorn is not the primary, but a secondary source of PPV. On the other hand, sweet and sour cherries at localities of central and westernBohemia, and of southernMoravia are PPV-free. Till now the presence of strain PPV-C was not proved in theCzechRepublic. Strain PPV-M was proved only in two plum and one damson trees. It was also found in one apricot and one peach orchard planted with imported nursery material. Strain PPV-M appears to have been introduced recently and is absent from or has a very low incidence in spontaneous PPV hosts, while the widespread and long-term dissemination of strain PPV-D may indicate that it originated in the Czech Republic.

Resistance to Potato mop-top virus (PMTV) was studied in Nicotiana benthamiana and potato (Solanum tuberosum cv.Saturna) transformed with the coat protein (CP) gene of PMTV. In N. benthamiana plants mechanically inoculated withPMTV, RNA2 was detected in leaves and roots in several plants in the absence of RNA3. When N. benthamiana wasgrown in infested soil, viral RNA was detected in roots, but no systemic movement of PMTV to above-ground parts wasobserved. The incidence of PMTV infections was reduced in the CP-transgenic potato plants grown in an infested fieldin Sweden. However, in infected tubers, all three virus RNAs were detected.

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.

It is indispensable to have accurate and speedy method of nematodes detection considering their great deal of malignancy nematodes. For identification of Meloidogyne incognita genetic primers were designed and the procedure was attested by Polymerase Chain Reaction.

Side effect of two herbicides (iodosulfuron-methyl/Na + mefenpyr-diethyl = Husar and isoproturon = Tolkan) on micromycetes on winter wheat was study. Herbicide treatment reduced the whole number of fungi and number of genera in phyllosphere. It reduced number of the rhizosphere fungal genera, too. Population of Chrysosporium sp. markedly increased after Husar application, whereas population of Trichoderma harzianum was markedly reduced. Tested herbicides inhibited the development of Fusarium avenaceum on wheat leaves. Iodosulfuron-methyl/Na + mefenpyr-diethyl significantly reduced the growth of F. avenaceum in vitro.

In order to identify components of the defence signalling network that may contribute to the establishment of disease resistance, we generated a novel PR-1::Luciferase transgenic line which was deployed in an imaging based screen to uncover novel defence-related mutants. Approximately, 5000 ethylmethane sulfonate (EMS) lines and 30 000 activation tagged lines were generated and screened for enhanced LUC activity via ultra low light imaging.

Resistance to root knot nematode M. chitwoodi has been identified in the wild tuber-bearing Solanum species, S. bulbocastanum. Three pathotypes were identified suggesting at least two different genetic factors for virulence and resistance in the pathogen and the host species, respectively. Roots of S. bulbocastanum were infested with two isolates of M. chitwoodi differing in virulence. The infection process was monitored by histological examination of roots allowing time points to be identified. cDNA libraries were constructed from infected root tissue using Suppression Subtractive Hybridisation (SSH) to enrich for transcripts from either compatible or incompatible interactions, at three days and seven days post infection. Both plant and nematode genes, which may be important during the host/parasite interaction, were identified.

Water regimes of extensively used grasslands (one cut per year, two cuts per year, no cut, mulching) were determined and compared by drainage lysimeters in 1998-2000. Although the botanical composition and yields of experimental swards were different, there was no statistically significant difference in their water regime (only the soil moisture content of no-cut variant was significantly higher than in other variants). A determinant factor for the water regime of grasslands (GR) is the sum of rainfall over the growing season while the GR water regime is influenced by land use immediately after the cut. Water runoff from the soil profile 0.0-0.60 m (water supply to the groundwater level) was found to be negligible in the growing season, a substantial groundwater recharge occurs in an off-season period and/or at the beginning of growing season. Mulching was not proved to reduce evaporation. The best type of management providing for the economical water regime appears to be a one-cut variant. Relationships between botanical composition and GR water regime are also described.

The monitoring was carried on in the years 1996-2000 in the international IOSDV (Internationale Ökologische Stickstoff Dauer Versuche) field trial running since 1983 in Lukavec, Pelhřimov district. In the given locality, there are low fertility sandy-loamy cambisoils, long-term average annual rainfall 653 mm, average annual temperature 7°C, altitude 620 m. In the field trials there were introduced different organic fertilizations and graduate N-doses. According to the complex diffusion analysis, statistically significant for the yields of winter wheat after potatoes was the impact of N fertilization, years, and double interactions, with the exception of different organic fertilization. The N doses up to 120 kg.ha^-1 after potatoes proved to be optimal from the viewpoint of winter wheat yields and quality. The situation was similar for winter barley. The results of diffusion analysis for individual years were analogical also in straw yields of both cereals. The highest N dose to potatoes (200 kg.ha^-1) resulted in the highest tuber yields, but the starch content was significantly lower. Graduated N doses increased in cereals the numbers of ears per m2, but the mass of 1000 grains mostly decreased. In addition, N content in grain and straw increased with N doses, while pH annually decreased by 0.1 to 0.4. On plots without organic fertilization the N-balance was equilibrated with the annual application of 120 kg N.ha^-1 with straw embedding after cereals at 90 kg N.ha^-1 and on plots with stall dung to potatoes already at 70 kg N.ha^-1. On plots without N fertilization, the balance was passive also in P and K on plots without organic fertilization. A balance surplus was obtained already with the annual application of 15 kg P.ha-1 and 83 kg K.ha^-1 and organic fertilization. With the annual fertilization with 22 kg P.ha^-1 and 83 kg K.ha^-1 and stall dung (30 t.ha^-1) once every three years the P and K content increased annually by 1 to 3 mg.kg^-1 of soil. Maximum levels of crop growing profitability were obtained with those doses of fertilizers with which also an equilibrated balance of nutrients was obtained.

The benefits arising from adoption of information and communication technology by farming businesses are explored, and the prospect of a digital divide appearing in the UK agricultural sector is discussed, drawing on results of research at the University of Plymouth. It is proposed that countries in Central and Eastern Europe will be subject to the same phenomenon, and that the potential disadvantage suffered by non-adopters of this technology will be sufficiently severe to justify both policy intervention and further research.

The aim of this paper is to summarize the results of the EU Phare ACE research project P97-8158-R, "Micro-economic analysis of farm restructuring in Central and Eastern Europe", that tries to fill the gap of theoretical as well as empirical research into the implications of continuing and evolving farm restructuring in CEECs on the efficiency of the agricultural production sector and the development of rural areas by focusing on the economic decisions and perspectives of farm operators, asset owners and rural households. For this purpose, surveys among family farms and farm enterprises were carried out in 2000 in Albania, the Czech Republic and Slovakia.

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.

Countries associated in the European Union pay great attention to the development of small and medium-sized enterprises. At the same time, however, the member states are concerned that following the EU enlargement strong migration flows on the part of new members are likely to occur. Therefore, it is in the interests of the member states to learn whether the citizens of candidate countries are internally motivated to run their own businesses and whether suitable conditions have been created, i. e. whether there are any factors negatively affecting the establishment of small enterprises. To this end, an extensive survey was carried out in the Czech Republic aimed at the above mentioned issues and at identifying favourable and unfavourable factors in the process of small enterprise establishment in transition economies, using the Czech Republic as an example.

This four years experimentation work was aimed at research on using various waste organic materials and especially timber bark in cultivation substrates as a substitute of peat. Sixty-four special isolated cultivation beds were established for this purpose, each of 4.8 m³ volume, in which 11 variants of substrates consisting of different proportions of different components in several replications were tested. Standard substrates Horticultural substrate B and RKS I. were used as controls. Another variant was used as a control for growing tests of plants in containers. All tested substrates were enriched with hydroabsorbent TerraCottem. In some variants reserve fertilisers with slow release of nutrients (Silvamix Forte) were applied. For cultivation testing of studied substrates four ornamental tree species (Alnus glutinosa, Fraxinus excelsior, Salix alba, Salix matsudana) were chosen. The best evaluated variants were the ones containing 50 and 75% of bark in combination with sand. The worst was the variant composed of chips and sawdust. Thanks to the use of hydroabsorbents, even the variant containing 100% of sand appeared to be very good. The tested trees had different reactions to the different types of substrates depending on their species requirements. The limiting growth factor for Alnus was the content of water in the substrate. Similarly, the content of available nutrients in the substrate was essential for Fraxinus. The hardwood cuttings of Salix not only rooted into the substrate in a few weeks, but also formed aboveground parts of the required sizes. Obtained data on growth parameters differed according to the diversity of requirements of the different studied species.

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.

In 1998 and 1999 a total of 84 samples of corn, predominantly from localities in southern and central Moravia, were collected either directly from fields (entire ears at harvest maturity) or as grain from merchants. The objectives of the experiments were (a) to determine, on the basis of the results from mycological and toxicological analyses, the basic spectrum of fungal contaminants of corn in the Czech Republic with special reference to the genus Fusarium, and (b) to determine by enzyme immunoassay the presence of major toxic metabolites such as deoxynivalenol (DON), T-2 toxin (T-2), zearalenone (ZEA), and fumonisins (FUM) in grain samples. From naturally infected corn, representatives of seven fungal genera were isolated under in vitro conditions in both harvest years. Most frequent were species of the genus Fusarium (mean contamination of 44.6%). The next frequent genus was Stemphylium (29.3%). Eight species of Fusarium were found. In both years the most frequent species was Fusarium graminearum (1998 - 42.75%, 1999 - 41.8%), followed by F. culmorum. DON was found in 95.2% of the samples; its content ranged from 25 to 285 µg/kg. The content of T-2 varied more than that of DON, ranging from 12 to 875 µg/kg. Zearalenone content was more varied than that of the trichothecene-type compounds; 17% of the samples did not contain ZEA, the maximum content was 110 µg/kg. No FUM were found in 17% of the samples; in the others, FUM ranged from 12 to nearly 1000 µg/kg. Compared with the other three compounds, fumonisins showed generally the highest levels.

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.

Like spores of many fungi, conidia of Blumeria graminis, the powdery mildew fungus of cereals, release extracellular material. It is released within seconds where conidial surface projections touch a leaf. This ECM is probably adhesive since centrifugation showed that forces greater than those due to normal wind speeds are needed to displace conidia. Also, ECM release is probably involved in rapid sensing of substratum contact, leading to germ tube emergence close to the contact site. Thus, ECM release apparently confers at least two benefits to pathogen survival.

Fourteen Potato virus Y (PVY) isolates were characterized. They represented PVYN strain only. However, application of serological and molecular genetic methods led to a more complicated characterization. For example, five isolates induced necrotic symptoms on tobacco plants typical of PVY^N, despite reacting as PVY^O serologically. Moreover, the PVY isolates were not identical according to molecular genetic properties. Typical PVY^NTN PCR products were observed for 11 isolates, but four of them (Hr220-5, Hr387-7, Nord 242 and Syn1Scot) did not produce potato tuber necrotic symptoms in infected cultivars. An immunocapture RT-PCR probing was developed using a set of 24 primer pairs derived from eight regions of the PVY genome. Using this method, five out of seven PVY^NTN isolates including the Czech standard PVY^NTN from the potato cv. Nicola were found to be identical. However, two PVY^NTN isolates and all the other probed PVY samples showed unique patterns, suggesting specific differences at the nucleotide level. This method enabled specific identification of individual isolates variability even within different PVY strains.

The occurrence and virulence of wheat yellow rust in Hungary was studied in the period of 1999-2001. Yellow rust in Hungary occurred only in traces in 1999, strongly spread and reached epidemic level in Röjtökmuzsaj (West Hungary) in 2000, and the epidemic explosion was in the whole country in 2001. Surveys of yellow rust showed the importance of pathotypes, whose virulence spectra (virulent for Yr2, Yr3, Yr6, Yr7, Yr8, Yr9, Yr17, YrA+, YrCV, YrSD) were able to math the unknown resistance genes. Among 78 Hungarian and foreign cultivars 29 were strongly infected by yellow rust.

The response of 22 winter wheat cultivars to artificial infection with Pyrenophora tritici-repentis has been studied in the field conditions for three years and in the greenhouse conditions as well. The set of cultivars included the cultivars registered in the Czech Republic and Swiss cultivar Arina known for satisfactory resistance to different foliar and head blights. High level of field resistance to Pyrenophora tritici-repentis was detected in cultivars Arina, Vlasta, Rialto, Athlet, Trane, Siria, Vega, Alana, Samara. Not all cultivars showed similar reaction in field and greenhouse tests. Correlation between results of the field and the greenhouse tests was significant for 18 of 22 cultivars. Arina, Vlasta and Vega showed acceptable field resistance and high resistance in the greenhouse tests to Pyrenophora tritici-repentis too. The greenhouse experiments helped to differentiate between examined isolates collected from the territory of the Czech Republic. Cultivar reaction to isolates No. 98001, 98007, 98010, 00071 correlated significantly with the field results.

During trials (1998-2001) in the strawberry's plantation of the cv. Marmolade we monitored the appearance of the most important fungal diseases, their biology and possibilities of integrated control. Monitoring the biology of the determined fungi we established the way of overwintering, appearance of fruiting bodies and discharging of spores as well as beginning of primary infection and first symptoms of the following fungi: Mycosphaerella fragariae, Diplocarpon earliana, Gnomonia comari, Phomopsis obscurans on leaves and Botrytis cinerea on fruits. While checking the efficacy of fungicides, those most effecting to leaf diseases were Folicur Multi and Quadris, and on B. cinerea Switch and Teldor. Testing the resistance on botryticides the fungus B. cinerea showed low level of resistance to anilinopyrimidines and phenilsulfamides and high level to dicarboximides.

In the last decade, the character of agro-food chains functioning has changed significantly. Globalisation elements in the food processing and distribution are changing conditions in agro-food sector and influencing also agrarian markets. Due to higher food finalisation and market force of processing and distribution stages in the agribusiness commodity vertical, farm value share in the final food price has decreased. Increasing competition makes agribusiness firms look for possibilities to strengthen their competitiveness, which is increasingly determined by the ability to develop successful partnerships within commodity verticals, i.e. vertical integration, eventually co-ordination, enforces. In this study, potential benefits and risks of these forms of vertical interconnection are reviewed with respect on specific market and production characteristics of agro-food chains. The problem is presented on the example of the commodity chain of bakery and pasta production in the Czech Republic. At the end of the paper, main arguments for the interconnection of particular stages of this vertical are derived, especially between mills and bakeries.

The paper is focused on the evaluation of the development of financial situation of agricultural co-operatives in the CzechRepublic in 1997-2000 operating in both productive and marginal regions. The comparison of financial situation in these two groups of agricultural firms comes from the classification of firms according to productive regions. Presented results cover firms from the sample of agricultural firms observed in the RIAE Praha. Development tendencies of agricultural co-operatives in these two regions are analysed by means of chosen debt, liquidity, activity and profitability indicators. Non-financial indicators enlarging the above mentioned characteristics of firms' financial situation are suggested and analysed in the last part of this paper.