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The localization of cysteine proteinase PLCP-2 was investigated in potato plants (Solanum tuberosum L.) cultivar Désirée by electron microscopy. Healthy and PVY^NTN infected potato plants were grown in vitro on media with or without a supplement of jasmonic acid. We had already shown that PLCP-2 is present in leaves, stems, tips of shoots and tips of roots of healthy and PVY^NTN infected plants. It was detected in various cell types in protein bodies in vacuoles, in cytoplasm and in cell walls. There were significantly larger amounts of PLCP-2 in plants grown on medium with a supplement of jasmonic acid in both healthy and virus infected plants. More protein bodies in vacuoles were found in plants grown on medium with addition of jasmonic acid.

Substitution lines with the chromosome 3B of the Czech alternative cultivar Česká Přesívka (CP) in the genetic background of the wheat cultivars Zdar, Vala, Košutka, Jara and Sandra, differing in their requirements of vernalisation and photoperiod, were compared with the original cultivars under short and long photoperiod, to evaluate the effects of genes, located on the chromosome 3B of CP, on earliness and the response to photoperiod and vernalisation. The results suggest that these genes have only a small effect upon the vernalisation requirement, but are more related to the response to photoperiod. However, the genes on the substituted chromosome appear to influence the earliness per se and very likely interact also with the photoperiodic response.

Chromosome 4A of Triticum macha carries resistance to Fusarium head blight (FHB). Double haploid lines (DH) of T. macha 4A were used to determine the type of resistance and location of the gene(s). FHB resistance and yield trait data collected over two seasons following spray and point inoculation, indicate that the resistance is of type I and is probably conferred by a single gene. The resistance was mapped with microsatellite markers to a small area of the T. macha 4A chromosome flanked by markers gwm 610 and gwm 165. This could greatly facilitate future marker assisted selection work aimed at increasing resistance to FHB in other winter wheat lines.

Parameters characterizing N mineralization and nitrification were measured in soils of ten monitoring areas of the basal soil monitoring carried out by the Central Institute for Supervising and Testing in Agriculture. A remarkable seasonal cycle was found only for nitrate concentrations that reached their maxima in the spring (April-June), and late summer and/or autumn, starting in August. Ammonium ions were nitrified immediately after fertilizer application. Anaerobic N mineralization represented a variable parameter, which was not directly affected by mineral N fertilizers. Nitrification measured by means of one-week incubation was significantly stimulated by N fertilizers confirming that substrate availability was a limiting factor of this process. Short-term nitrification activity (SNA) showed no remarkable seasonal fluctuations, which meant that the potential nitrification rate remained relatively constant during the season. Urease activity was mostly constant during the year and was only slightly related to N mineralization.

Field experiments were conducted in the maize-growing region on heavy gleic fluvisol from 1974 to 2000. Three variants of straw management (straw harvested, incorporated into soil and burned), two variants of soil tillage (conventional plough tillage to 0.22 m, shallow disc tillage to 0.12-0.15 m) and three variants of fertilization (30, 60 and 90 kg N.ha^-1) were studied. After conventional tillage, the highest yield was obtained in the variant with burned straw (5.50 t.ha^-1), followed by the variant with straw incorporated into soil (5.40 t.ha^-1) and the lowest after harvested straw (5.01 t.ha^-1). At shallow tillage, lower yields were assessed in all variants of straw management in comparison with conventional tillage (after straw burning 5.07 t.ha^-1, incorporation into soil 4.66 t.ha^-1 and harvest 4.54 t.ha^-1). The ranking of variants was identical to that in inversion tillage; however, the yield increased more after straw burning in comparison with its incorporation into soil. Yields increased regularly along with increasing rates of nitrogen. If long-term effects of straw incorporation on yields and yield trends were evaluated (in comparison with straw harvest), statistically significant decrease in yields was assessed after shallow in contrast with increase in yields after deeper straw incorporation.

Glucosinolates with Brassica genus as secondary metabolites have a lot of functions and effects. Glucosinolates form less than 2% of the overall sulphur content at the beginning of vegetation in different parts of the plants and during growth their content is decreasing and forms less than 0.1%. This low representation doubts their storage function. With its chemical composition, they are ranked among natural pesticides with active and passive resistance against diseases and pests. They show repellent effects and properties of natural biofumigators in soil after ploughing in their biomass as green fertilizing, or after ploughing in after harvest the leftovers of rape. The principle of these effects is decomposition products of glucosinolates - bioactive isothiocyanates. Very important from this point of view are turnip rape Rex and Brassica juncea, whose content of these compounds is the highest one and they are resistant against the attack of Ceutorrhynchus pleurostigma. The same effect showed also when attacked by Phoma lingam. With other winter Brassicas either hybrid or linea and summer rape is this defensive system suppressed because of their lowered content due to breeding interferences, leading to limitation of their anti-nutritional negative effects. It is possible to state the final result after finding out the production of the above matter, roots, and after evaluation of the sorbal characteristics of the soil and evaluation of the state of health of the following crop or vegetable. After this overall analysis, it will be possible to evaluate the biofumigation properties of accessible varieties of the Brassica genus.

The efficiency of the application of organic and inorganic additives on the reduction of mobility and transfer of As, Cd, Pb and Zn from the soil into the plants was observed. The dung, compost, acid peat and muck presented organic additives. Synthetic zeolite - type Pc of cubic structure, loamy shale and dolomite limestone presented inorganic additives. Five soil types were used during the testing (arenic regosol, typic cambisol, dystric cambisol, typic chernozem and typic fluvisol). The changeover of the mobility of As, Cd, Pb a Zn in the soil (the ratio of mobile and total contents, sequential analysis) and the transfer of the elements from the soil into the plants (the vegetables, cereals and fodder plants) were investigated. The results showed the primary importance of the soil pH value on the behaviour of potentially toxic elements and their intake by the plants. The efficiency of the use of organic additives strongly depended on the quality of the organic matter. Inorganic additives on the base of the sorbents worked in the case of mobile hazardous elements (Cd, Zn). The efficiency of the soil additives was strongly influenced by the soil type.

The old debt problem resulting from the transformation of the agricultural co-operatives of the former GDR (German Democratic Republic) is described with respect to its evolution and its economic policy treatment during the process of transformation. So far, the measures for the treatment of old debts have had business economically stabilising effects. Nevertheless, debts are still growing. The farms which are affected by such old debts are strongly interested in solving this problem. This explains the intensity of the results' discussion of a scientific expert opinion on an analysis of the mode of action of the old debt regulation in agriculture. The conclusions which can be drawn from the public discussion of these results with respect to the future treatment of these old debts show, that the affected farms favour a kind of bonus rule for debt repayment. Such a regulation also seems to be acceptable for the treasury as the final bearer of the remaining debts and as a solution to minimise the taxpayers' burden.

Environmental analysis in the winegrowing industry is necessary for strategic management of businesses in this industry. The paper is focused on PEST analysis and pays attention to individual factors. It emphasizes the necessity of adjustment of the Czech legislation to the EU conditions, fulfilment of its conditions, e.g. compulsory registration of vineyards. In the field of economics, it is necessary to pay attention to renovation of vineyards with the help of subsidies from the state budget because the industry contributes to keeping the cultural level of the region and the human resources on the territory. It can be also a source of the environmental pollution. The technology of vine processing follows the changes in viniculture, changes of growing-technology and of the structure of white and red varieties. In conditions of the Czech Republic, it means to gradually transfer to production of quality varieties of vines by gradual renovation, which has to be a priority. The winegrowing sector is the industry with the highest value added also in the Czech Republic, and its share in the total agricultural production in a region can reach a significant level.

Productivity and its stability were evaluated in a set of 24 apricot genotypes of the world collection and some promising new selections in 1994-1999. The productivity of most genotypes was higher than that of control variety Velkopavlovická LE-6/2. Genotypes with higher productivity in the years favorable for apricot productivity gave higher yields also in the years unfavorable for productivity. It was proved by a significantly close highly significant correlation (r = 0.64++). It is a reason for the necessary regulation of fruit set in highest-yielding varieties in the years favorable for apricot productivity when overproduction and undesirable reduction in the fruit size occur. The variability of yields in kg per tree, expressed by coefficients of variation over a six-year period, was high in the years of observation. The variability of yields was significantly lower in the years favorable for apricot productivity. To express yield variability the coefficient of variation and index of fluctuation can be used. Their similar conclusiveness was proved by the significant positive closeness of correlation between the values determined by both calculations (r = 0.51+). The varieties Vynoslivyj and Volšebnyj showed the highest and most stable productivity. From the producer's and breeder's aspects, of these two the Vynoslivyj variety is one of the most remarkable genotypes of the evaluated set due to its fruit quality and late ripening.

Superoxide dismutase (SOD) isoenzymes of the rumen bacterium Streptococcus bovis 4/1 were studied. Native PAGE showed a single band of Mn-SOD, unaffected by 10 mM cyanide or 5 mM hydrogen peroxide under both aerobic and anaerobic growth conditions. When the metals were removed from the growth medium by Chelex 100, the addition of manganese increased enzymatic activity, while addition of iron inhibited SOD activity. Changes in Mn-SOD and glutathione peroxidase (GSHPx) activities evoked by paraquat and increased values of TBARS indicated that these enzymes were not able to sufficiently prevent oxidative stress at given paraquat concentrations.

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.

For 6 years the flight activity of pests on winter and spring oilseed rape was studied from spring till harvest, using yellow traps. In all years the flight intensity was higher in winter rape than in spring rape. The dominant insect pests of winter oilseed rape were Ceutorhynchus obstrictus, C. napi, C. pallidactylus, Dasineura brassicae, Meligethes aeneus, Phyllotreta atra and Ph. nigripes; subdominant were Athalia rosae, Brevicoryne brassicae and Psylliodes chrysocephala. In spring rape the dominant species were Brevicoryne brassicae, Ceutorhynchus obstrictus, Dasineura brassicae, Meligethes aeneus, Phyllotreta atra and Ph. nigripes; subdominant were Athalia rosae, Ceutorhynchus napi, C. pallidactylus and Psylliodes chrysocephala. Dasineura brassicae was not evaluated from trap catches. The damage by D. brassicae is higher to pods on axillary branches than on the main inflorescence. The occurrence of pests on spring rape was tied to a unsuitable phenophase of the plants at the time of flight activity and to the suitability of food. Winter rape requires a higher intensity of chemical treatment against pests than spring rape.

Wheat dwarf virus, a monogemini virus, infects several cereal species. Until now complete sequence data have been published only for wheat isolates. We cloned the complete DNA of 21 isolates from wheat, barley and Lolium spec. and compared the sequences with published data. Two types of the virus were found as previously described. Degree of entire nucleic acid homology between both isolates was in the range of 84%. The Large Intergenic Region showed most pronounced differences while the RepA gene was most conserved. No intermediate forms were found, though both isolates co-existed in the same hosts. Sequence data lead to the suggestion that they should be referred to as different viruses rather than strains of a virus.

Beet soilborne pomovirus (BSBV) was observed both in the sap and in tissues from local lesions on Chenopodium quinoa leaves after their embedding into acrylic resin LR White. Immunocapturing with polyclonal antibodies was used to enhance number of particles on grids and immunolabelling by colloidal gold was used for better visibility of virus particles in tissues. BSBV has rod-like particles of various length and it forms inclusions of several particles adhering side to side each to another.

Tan spot, caused by Pyrenophora tritici-repentis (Died.) Drechs., anamorph Drechslera tritici-repentis is one of the most important wheat diseases in the world, especially in the regions of intensive wheat growing. Tan spot had established for the first time in Latvia in 1994. Epidemic of this disease was observed in Latvia in 1998. Development of tan spot were investigated in field experiments at the Research and Training Farm "Peterlauki" of Latvia University of Agriculture in 1998-2001. Level of incidence and severity of tan spot differed depending on varieties and years. Severity of the disease was 16-71% in 1999; 0.1-5% in 2000 and 4-18% in 2001 depending on varieties at the time of ripening. 1999 summer was extremely dry, and development of disease was not observed. Explosion of disease was observed at the second half of June in 2000 and 2001, without reference to varieties. Date of increasing start differed, but in all cases important development was observed after flowering. Rate of increasing of disease was very high, during two weeks severity of disease increased from 0.1 till maximum of severity. Amount and frequency of rainy differed in 2000 and 2001, but increase on disease was very similar, it means, we need more information about favourable conditions for Drechslera tritici-repentis. Sexual stage Pyrenophora tritici-repentis was observed in Latvia for the first time. Further investigations are necessary, because relationships between meteorological conditions and stages of development are unclear.

The virulence frequency to 12 resistance genes present in the studied cultivars in the time before their first using in grown cultivars were estimated mainly based on the data of cultivar resistance in the field. The estimated virulence frequency is compared with results obtained from investigations of the air pathogen population in 2001. The comparison shows that virulence complexity increased from about 0.90 in 1971 to 8.73 in 2001. The increase in virulence complexity was caused by necessity of the pathogen to survive on cultivars possessing respective resistance genes, it means by direct selection [(Va1, Va6, Va7, Va9, Va13, Vat, Vk1, VLa, Vg and V(Kr)], indirect selection (Va12) and immigration (Va3).

In the framework of PVS eradication from breeding materials of Czech potato cultivars, the systematic research was devoted to: susceptibility of cultivars, occurrence of PVS in imported and domestic materials, and to maintenance of virus-free basic grades potatoes on breeding stations. In the field-exposure trials was proved high level of susceptibility of most cultivars to PVS and by contraries, gradualy increased proportion of maintained virus-free cultivars of foreign, as well as domestic origin. Nevertheless severe infestation still persist in some of them. The contemporary situation with maintenance of virus-free basic material in CR was demonstrated.

Five cultivars of spelt wheat (Rouquin, Bauländer Spelz, Schwabenkorn, Franckenkorn and Holstenkorn) have been evaluated for baking quality by means of direct and indirect indicators. Three-year values of the indirect indicators have been statistically processed by the analysis of variance. Based on the results obtained we can say that all evaluated indicators except the extensibility of gluten were significantly influenced mainly by the year of growing. The cultivar itself was a less important source of variance, although some values of important indicators differed significantly according to cultivars. Based on indirect indicators such as the content of wet gluten, its extensibility and swelling, the content of N-substances, the sedimentation test in the modification with SDS, the falling number and the content of starch, the cultivars Schwabenkorn and Rouquin are considered as the most suitable and of the highest quality. In general all the cultivars of Triticum spelta L. showed high contents of N-substances (x = 15.46%) and wet gluten contents (x = 37.12%). Their disadvantages are lower swelling values (x = 9.3 ml) and lower sedimentation values (x = 37.4 ml) which have a negative influence on the bread volume and the specific volume (under 310 ml.100 g^-1). The predicted good baking quality of Schwabenkorn has been comfirmed in a baking experiment (direct method of evaluating the baking quality). There were good baking quality results for Bauländer Spelz as well. Unexpectedly bad results have been found with Rouquin, which showed the lowest water absorbing capacity of flour, the lowest bread volume, specific volume and baking extraction. The bread was just acceptable as far as taste is concerned. The baking from Holstenkorn was evaluated as excellent.

The processes of globalisation and concentration have been also penetrating into the Czech agro-food sector and market. Utilising information from foreign sources and developed countries, the paper tries to present a complex view on the Czech situation from the structural and institutional aspects. Based on limited Czech information sources, the market structure in the individual links of the food chains is presented, together with the hypothesis about the sequence of the market power in the present Czech agro-food sector: input suppliers and retailers - farmers - processors. The paper also implies possibilities of the state to suppress negative effects of globalisation and concentration, especially as regards the adjustment of the Czech market regulations to the EU ones.

Formation of strategic development intentions of Czech agriculture is determined from a viewpoint of external factors by European integrating processes and strengthening tendencies of globalisation. This multi-dimensional process is a driving power and at the same time also an eliminating factor of many development trends. The sustainable dimension of globalisation is formed in the frame of the world society, world economics, world ecology and world policy. Problems of world agriculture are represented by the intersection of these trends and present a starting point for the formation of the European and Czech agricultural policy.

Since 1990s, the discussion about the Czech social policy emphasizes more the necessity to change this policy from passive state social policy towards an active social policy. The latter includes the activities of people in the frames of formal (e.g. NGOs) and informal groups, and therefore also the concept of civic society is accentuated in this respect. Although this concept might be understood in different ways, its common characterization is a spontaneous non-political self-expression of individuals and their groups (the activity that was suppressed before 1989). Through the self-expression, the individuals realize their particular interests. When thinking about active social policy in the frames of civic society, we might assume that the conditions for its implementation are better for the actors in small rural communities. These more favourable conditions are assumed due to the traits of rural communities - e.g. personal, non-anonymous relations, good knowledge and familiarity with particular social problems, etc. However, the actors who try to contribute to active social policy are constrained/controlled in their activities by other community members. The level of these constrains depends on the configuration of social and cultural capital (Bourdieu). The author of the text is for more than one year involved in empirical research in one Czech village. Using qualitative methods she investigates various social events and actors who participate in active social policy (in relation to those who are supposed to participate in this policy as responsible agents). The author assumes that the participation in active social policy is one of the sources of integrated endogenous rural development, while passive social policy (institutionally backed by the state) is more related to exogenous rural development. However, there is a question how the very actors (active members of rural community) do approach this participation and how the other members of rural community evaluate their activities in the sphere of social policy.

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).

TPY agar supplemented with mupirocin (100 mg/liter) and glacial acetic acid (1 ml/liter) was effective in the enumeration of bifidobacteria in animal (11 species) fecal or intestinal samples. On the other hand, less than 50% of isolates from pig feces were identified as Bifidobacterium sp. using this medium. Subsequently TPY agar modified by the addition of mupirocin (100 mg/liter), glacial acetic acid (1 ml/liter), and colistin (25 mg/liter) was developed for the enumeration of bifidobacteria in pig feces. The results suggest that the bifidobacteria selective media should be chosen in respect of the animal species origin of the samples tested.

The major insect pests on rice in Tanzania are listed and described. They are from five orders (Coleoptera, Diptera, Hemiptera, Lepidoptera and Orthoptera) and are discussed as stem borers, stem and root feeders, and leaf and panicle feeders. This review puts together the hitherto fragmented information available on the distribution, host range, biology/life-cycle and ecology, and the management measures of the insect pests of rice. Areas for future research are also mentioned.

Limited information on the resistance mechanisms in Lycopersicon spp. to Oidium neolycopersici is still available. Macroscopically the resistance is characterized by a very low amount of mycelium development and a lack of sporulation. The leaf surface did not effectively inhibite conidium germination, however significant differences in germ tube and appressorium development were recorded. A large variation was observed in host tissue response. The prevailing resistance mechanism was hypersensitivity (HR). Considerable changes of peroxidase and catalase activities during pathogenesis were detected among tested wild Lycopersicon spp. There was positive correlation between increasing of peroxidase activity and extent of necrosis. Histochemistry showed large differences in production of superoxid ions, H₂O₂ and peroxidase in Lycopersicon spp. with various level of resistance.

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.