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The relationship between gliadin alleles, known to mark frost tolerance, and actual frost tolerance was investigated in 52 doubled haploids (DH) from the cross Florida× Vlada. Frost tolerance was expressed as percentage of plant winter survival in pots placed at different heights above the ground. Gliadin allelic blocks (GLI) were determined by starch electrophoresis. From the six GLI, known as frost tolerance markers, the GLI 1B1, GLI 1D5 or GLI 6D2 was present in 27, 27 or 31 DH, respectively. A weak, but significant correlation of r = 0.29 was found in the DH between their survival and frost tolerance prediction values based on the presence of the gliadin frost tolerance markers. The average survival of DH with gliadin frost tolerance marker GLI 1B1 or GLI 6D2, but not with GLI 1D5, was significantly higher than the survival of DH without this block. The DH without any gliadin frost tolerance marker had the lowest survival. Some gliadin genes thus can be used as frost tolerance markers for preliminary selection of frost tolerant lines and for the study of physiological and genetic constitution of frost tolerance in common wheat.

The aim of this study was to develop a protocol for production of polyploid M1-generation plants of Viola × wittrockiana Gams. Two variants of colchicine treatment were compared for their efficiency. Early detection of novel ploidy levels was achieved by screening of stomata size, leaf index value (leaf blade length/width), and other morphological characteristics of the M1-generation. Secondary screening for novel ploidy levels was performed by flow cytometry (FCM). Hexadecaploid, aneuploid, and mixoploid plants were successfully identified by FCM.

Age and diameter classes or growth stages as criteria for the implementation of thinning

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.

The contribution firstly mentions a determination of possible approaches to the problems of regional development. The contribution content is the characteristics and comparison of the regional policy level in the European Union and the CzechRepublic. In the European Union, this policy has developed for a long time and it has been modified to the form which it has at the beginning of the 21st century. In this, it is a continuous process. On the contrary, in the Czech Republic during directive management, regional policy was not formulated and most of decisive processes were centralised. Since the beginning of 90ies, significant changes have taken place and in 2000 it was possible to say that the necessary presumptions for the use of efficient regional policy principles had been created.

The foreign agri-food trade has showed an unsuitable development for the Slovak Republic during the 1999-2001s. The negative balance for the competitive commodities is increasing. These are the commodities for the production of which the SR has suitable natural conditions. The contribution deals with the selected competitive commodities in the kilogram prices. The study shows the decreasing tendency of kilogram prices in import and the increasing tendency in export. Higher export price is the consequence of the higher value added and thus also higher revenues.

Pythium oligandrum Drechs. belongs to the order Oomycetes. It is parasitic on many fungi from the same or other orders. The antagonism of P. oligandrum is a multifaceted process dependent on the target species involved. P. oligandrum is nonpathogenic on 12 species of crops from six families. It does not attack their tissue but occurs on the root surface, predominantly in the regions of hypocotyl - taproot, together with plant pathogenic fungi. It utilises the root exudates and fungus hyphae on the root surface, including those of the plant pathogens, for its own support. A growth stimulation of plants was observed. P. oligandrum can be utilised for biological control on a wide spectrum of crop plants. Different methods of application have been developed. The effect of a mycoparasite preparation is more preventive.

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.

Overproduction of sugar causes a reduction in the acreage under sugar beet. That is why new non-food technologies for exploitation of agricultural products are sought. Utilization of beet for liquid fuel production could be one of them. The aim of experiments with sugar beet raw juice fermentation was to verify the possibility to return a part of distiller's slops back to the fermentation process and thereby to obtain stillage with higher content of dry solids. This would bring about energy savings during slops thickening and drying. Tests with recycling of different portions of stillage (20, 25 and 30%) back to the fermentation stage were carried out. No significant increase in dry solids content in mash was found and therefore no energy savings during thickening can be expected. The only savings can be made in water consumption that is replaced by slops.

Leaf spot pathogen is characterized as a highly developed parasite after investigation of development peculiarities of the fungus in pure culture and natural conditions. The degree of correlation depended on the medium. Impact of incubation temperature on Blumeriella jaapii (Rehm) Arx growth was different. Fungi colonies formed more intensively and their diameter increased significantly under higher temperature. Optimal conditions for the disease prevalence are 15-20°C and moisture. Relative humidity and precipitation influenced maturation of ascomycetes and discharge of ascospores (r = +0.89). Microscopic analysis of leaves showed that during winter thaw, when the average temperature is about 0 ± 5°C and relative humidity is higher than 70%, was possible to detect mature ascomycetes and conidia. It is possible to affirm that lower temperature than it was assumed is sufficient for formation of ascomycetes.

Viruses as phytopathogenes have been discovered at 1892, and 638 plant's viruses have been identified at 1989. Some of its may be epidemic and to cause significant yield losses of cultivated crops. Increasing resistance of the single plant and populations is the necessary condition for the control of viruses spread and damage. Our proposals for the increasing resistance to viruses: For the single plant the soft correction of plant's metabolism with pretreatment of the natural bioantioxidants and immunizators - steroid glycosides. It results in lowering of virus infectivity, degree of plant's affection and increasing of the yield on 11-41% in fact (in ToMV-tomato pathosystem). For the plant's population- increasing to the necessary proportion the lot of tolerant and resistant forms into the plant's assortment; - selection of resistant and tolerant forms from populations have been selected earlier as resistant to other pathogens and obtaining of the basic material collection with complex resistance; - hybridization programs and developing of tolerant and resistant hybrids; - use molecular markers of resistance for the limitation of virus infection backgrounds in the breeding programs.

The effectiveness of fenarimol and difeconazole, DMIs fungicides, and dodine was tested in two experimental orchards and in greenhouse in two seasons. In 2001 monitoring of resistance to dodine was conducted also in some commercial orchards located in main apple production. In both experimental orchards fenarimol gave significantly poorer control of apple scab than difenoconazole when curative treatments were applied. The same results were obtained in greenhouse tests using for inoculation the suspension of conidia of V. inaequalis from these orchards. In many monitored orchards, in each region, a high level of dodine resistant isolates in population of V. inaequalis (even more than 40%) was noted. Only in six from 65 tested orchards there was less than 1% resistant isolates in population of the fungus.

Both spring and winter barley were sown after a forecrop of winter rape. Three registered model varieties of six row and two row winter barley reached in the period 1999-2001 significantly higher yield than three model varieties of spring barley. Two row spring and winter varieties produced significantly higher thousand grain weight (TGW) than six row winter barley. The resistance to diseases and lodging (correlation coefficient with resistance to powdery mildew represent 0.68**, rust 0.72*, lodging 0.61**) was the most important factor determining the yield. Resistance to rust has influenced sieving on 2.5 mm, correlation coefficient reached value 0.88**. No significant differences were determined in any malting quality parameter when varieties of two row winter barley variety (Tiffany), and spring barley varieties (Akcent and Tolar) were compared. Variety Tolar reached higher parameters for friability and a beta glucan content. Between years, significant differences were found in following parameters: protein content and apparent degree of attenuation. Due to reduction of area sown with spring barley and reduced yield potential, two row winter barley varieties with comparable malting parameters are recommended to be cultivated as the reserve crop for malting barley industry demands.

The goal of the investigations was to assess the average contents of heavy metals (Pb, Zn and Cd) in the surface soil layer (0-30 cm), in drainage water and their uptake by growing plants, in the experimental amelioration field for four different variants of drainpipe spacing (15, 20, 25 and 30 m) during the three-year period. Maize and winter wheat were grown in all variants throughout the trial period. In all variants of drainpipe spacing, heavy metals in soil, drainage water and plant material were within the limits. The highest average level of Pb was 13.5 mg/kg, Zn 88 mg/kg and Cd 0.7 mg/kg in soil. Drainage water concentration of heavy metals was below 50 µg/dm³ for Pb, below 2 µg/dm³ for Cd, while the highest average value of Zn amounted to 20 µg/dm³. In grain of the crops grown, the concentration of Pb was below 0.4 mg.kg-1 and that of Cd below 0.1 mg/kg.

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.

Agriculture is a traditional branch for the Republic of Bulgaria. The favourable agriclimatic and soil conditions further the growth of 145 agricultural crops and the production of various products, many of which have leading positions in the international market. The aim of this paper is to examine the nature and specific features of the reform of the land relationships in the Republic of Bulgaria during the period of transition towards market economy. The development of land relationships in this country reflects the economic interests of its society, which show their specific nature in the relationships between the owners and the leaseholders of the plots. It is typical for this country that during the collectivisation period, which took place in the middle of the last century, the land, being the basic production factor in the agricultural branch, was public property, the private character of which was never abolished. During the transition period, a process for restoring the land 'within its real borders' was started. This led to delay in the reform and a significant fragmentation of the land. The completed agricultural reform contributes to the recovery and precipitation in the process of developing of the land relationships in the country. A sign of this is the formation of land market. In the year 2001, 28 878.1 ha changed their owners, and another 280 000 ha were leased. The aim is, through active laws, to achieve synchrony of the social interests with the interests of the owners and leaseholders and to create conditions for optimisation of the production process in agriculture. A favourable economic environment will contribute to increasing the efficiency of the agricultural branch in the Republic of Bulgaria and to the formation of the land relationships, which will facilitate the process.

The studies aimed at monitoring development of phagocytic and bactericidal activity in carps in the course of their ontogenetic development. The studies were performed using the techniques described by Mantur et al. (1986a, b), adapted to fish. Results were expressed in thrombocyte phagocytic index (Ipt), percentage of phagocyting thrombocytes (%tp), percentage of ingested bacteria (%bp) and in the index of intracellular killing by thrombocytes (Ibt). Number of thrombocytes was also examined using the technique of Dessi. Results of testing thrombocyte capacity to ingest the standard Staphylococcus aureus 209P strain showed that Ipt and %tp increased gradually in carps between the age of 3 and 17 months. In older carps, 19 to 29 months of age, as well as in spawners the growth in activity paralelled the ontogenetic development within Ipt values while %tp values remained at a similar level. Phagocytic activity of thrombocytes expressed in Ipt was reflected also by %bp values, which was particularly evident in fish aging 23 months to 5 years. In the case of Ibt, values of the index were not related in any way to stage of ontogeny or sex of the fish. Number of thrombocytes in carps aged 3 months to 5 years was increasing in parallel to their ontogenetic development.

The objective of this study was to establish the genetic relationship among cultivars commonly used as donors for resistance to Plum pox virus (PPV) in order to identify the putative sources of resistance to PPV. The plant material tested represented the European, Central Asian and Chinese ecogeographical groups of cultivated apricots as well as the wild Dzhungar-Zailij population of Prunus armeniaca L. Forty-eight native accessions as well as the resistant (or tolerant) cultivars Harlayne, Stark Early Orange (SEO), Goldrich, Vestar and two hybrid forms Vestar × SEO (LE 3276) and Velkopavlovická × SEO (LE 2904) were screened by means of SSR analysis. To elucidate genetic relationships among apricot germplasm, a dendrogram was produced using neighbor joining (NJ) analysis of Nei's pair-wise genetic distances over 14 polymorphic SSR markers. On the dendrogram, resistant cultivars were separated into two different clusters suggesting two different sources of resistance to PPV. As was expected from pedigrees, SEO, Vestar, LE 2904 and LE 3276 were grouped together in a cluster adjacent to the European cultivars. Resistant cultivars Harlayne and Goldrich were within another group containing Central Asian apricots and Dzhungar-Zailij form.

The aim of the work was to determine the effect of fungicides: Topsin M 70 WG, Bravo 500 SC, and Sportak 45 EC in two concentrations on the growth of fungi: Aspergillus niger, Epicoccum purpurascens, Cladosporium sphaerospermum, Mortierella isabellina and Penicillium verrucosum var. verrucosum on PDA and Murashige-Skoog medium (MS). The smallest index of linear growth rate of the fungi had Topsin M 70 WG for fungi: E. purpurascens and P. verrucosum var. verrucosum on PDA and MS medium and for M. isabellina and C. sphaerospermum on MS in concentrations of 71.42 mg/l and 107.13 mg/l. The highest index of linear growth had Bravo 500 SC in concentrations of 0.5 ml/l and 0.75 ml/l on PDA for E. purpurascens and A. niger. The lowest index of linear growth on MS for E. purpurascens, C. sphaerospermum and P. verrucosum var. verrucosum was noted down. The highest effectiveness in control of linear growth all tested species of fungi was found for fungicide Sportak 45 EC in concentration of 0.55 ml/l and 0.825 ml/l on MS and PDA. Among all tested fungicides used in vitro propagation fungicides from imidazoles group are recommended.

Using the Ames bacterial mutagenicity test and an in vivo micronucleus test, we investigated the antigenotoxic effect of ellagic acid on the genotoxicity of three mutagens: amino-methylimidazo-quinoline (IQ), aflatoxin B1 (AFB1), and N-nitroso-N-methylurea (MNU). Ellagic acid is a naturally occurring phenolic compound which is found in a variety of soft fruits and vegetables. The effect of this compound on the immunosuppressive activity of mutagens was followed in vivo by the chemiluminescence test. In the Ames assay, ellagic acid at concentrations of 300 and 30 μg/plate demonstrably inhibits the mutagenic activity of two indirect mutagens: IQ and AFB1. The concentration of 300 μg/plate had the strongest effect on mutagenicity of all concentrations of IQ in strain TA98 of Salmonella typhimurium, whereas in strain TA100 concentration of 30 μg per dish of ellagic acid was more effective than 300 μg per plate. Also in combination with different concentrations of AFB1, ellagic acid proved to be a strong antimutagen. In this case the lower of the two effective concentrations - 30 μg/plate - had a much greater antimutagenic effect on both strains tested than 300 μg/plate. In combination with the direct mutagen MNU, ellagic acid did not show any marked antimutagenic effect at most of the concentrations tested in strain TA100. Only the highest concentrations of ellagic acid reduced the mutagenic effect of MNU weakly and only in combination with two lower concentrations of MNU. In the micronucleus test, three-day oral application of ellagic acid prior to the applicaton of AFB1, IQ, or MNU, respectively, markedly reduced the numbers of micronuclei induced by these three mutagens in polychromatophilic erythrocytes of mice. Chemiluminescence test with mouse granulocytes proved that ellagic acid not only prevents the inhibitory effects of mutagens on free oxygen radicals and hydrogen peroxide production, but that this production is stimulated by ellagic acid in combination with mutagens even to a greater extent than by ellagic acid alone. From these results we can deduce that ellagic acid repairs strong immunosuppressive effects of all mutagens applied.

In order to investigate cross-protection mechanisms between stresses of different origins, greenhouse experiments were conducted to determine whether resistance levels to the fungal pathogen P. capsici were affected on wounded plants. To this purpose, tomato roots were wounded at 24h-intervals and allowed to age for up to 7 days before inoculation. Data from preliminary experiments indicate first (0-48 h old wounds) an increase in disease severity in wounded as compared to unwounded tomato plants infected with P. capsici. Then, as the wounds age, disease severity decreases to the point that plants wounded 3 days before inoculation are less susceptible than nonwounded plants. Here, with the use of tomato mutant lines, we suggest the involvement of ethylene (C₂H₄) and jasmonates (Ja) in the development of these responses towards P. capsici upon wounding of tomato plants.

Chamaecyparis lawsoniana is often attacked by other pathogens (from genera: Phytophthora, Pythium, Fusarium, Rhizoctonia) both when the quicksets are taken root and later, when the young plants are planted. The aim of the study was to determine an effect of saprobiotic fungi isolated from soil with quicksets Chamaecyparis lawsoniana on the growth of Phytophthora cinnamomi and Rhizoctonia solani. In our experiment, method series biotic was used (MAŃKA 1974). This method allowed to determine index of impendence for plants by Phytophthora cinnamomi and Rhizoctonia solani with the help of summary biotic effect. The results of observation on the biotic interaction of saprobiotic fungi isolated from soil with quicksets Chamaecyparis lawsoniana, analysed as biotic series and Phytophthora cinnamomi and Rhizoctonia solani showed, that this of fungal community did not limited growth of these pathogens. Summary biotic effects were negative. Environment of saprobiotic fungi more promoted growth of Rhizoctonia solani than Phytophthora cinnamomi. It means, that in the soil under Chamaecyparis lawsoniana crop, Rhizoctonia solani could have a better of conditions for growth than Phytophthora cinnamomi.

Trace elements with a low mobility and with a low transfer are Cu, As, Be, V, Cr, Hg. Copper has at low mobility an increased transfer quotient (content plant/soil). The lowest mobility and transfer show Cr and Hg. Only at the very high contents or increased mobilities of trace elements, which accompany the anthropogenic contamination, soil critical loading for crops can be attained. Because of the amount of the examined extremes, it was not possible to derive the proper critical values. Therefore we were able to assess only critical protective values. They represent minimum total contents of trace elements or their mobile forms, which eliminate risks.

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 laboratory incubation with glucose treatment was carried out in order to estimate the possible effects of increased microbial activity on heavy metal availability. The soils from vicinity of a lead smelter operating for more than 200 years were used for the experiment. The DTPA-extractable heavy metal contents increased after glucose addition and mostly reached the highest values the second day of the incubation. The comparative study, where the chloroform fumigation was used prior to the incubation in order to decrease the microbial activities, showed especially from second day of incubation significantly lower DTPA-extractable metal contents compared to non-fumigated treatments. The interactions among the maximum possible availability of DTPA-extractable heavy metal fractions and native soil microbial characteristics were studied in differently contaminated arable and grassland soils. Irrespective of different heavy metal contents in soils, significant correlations were found among the maximum percentage increase of DTPA-extractable Pb and Cd and the ratio Bc/TOC and metabolic quotient (qCO₂) which may be a result of the important role of organic matter and microbial characteristics in soils on the heavy metal availability.

Winter hardiness of genotypes pre-selected from Cerapadus × Prunus avium L. crosses was studied for 3 years (2000-2002) in comparison with clonal cherry rootstocks, presently grown in the Czech Republic using artificial freezing of the budwood applied just after the phase of deep dormancy. With a temperature drop to freezing, both the mean and the maximum rate of general frost injury was markedly increased. The greatest damage of the tested material (roughly at the level of LD 50 on the average) occurred after the application of combined low temperatures -25°C for 4 hours + -20°C for 66 hours. The results of laboratory tests were compared with the damage of natural frost that occurred during the first half of January, 2002. The single observed years did not differ from each other in the extent of injury, on the average. From standard cherry rootstocks, P-HL-B was generally the most sensitive to freeze injury. Its weak winter hardiness was approximately the same, or even somewhat worse, than that of rootstock Colt. The rootstock P-HL-C was classified as medium sensitive to winter frosts, while rootstock P-HL-A was scored as winter hardy. The average frost injury score of all 48 selected Cerapadus × Prunus avium L. genotypes included in the study was 6.7, whereas that of all control cherry rootstocks was only 5.9. According to the results of this study, the tested genotypes were classified into 5 groups with different classes of frost resistance or susceptibility. The most frequent was the class of medium resistance. The following five genotypes were the most winter hardy: CPH VODÁRNA, CPH 43, CPH 17, CPH 22 and CPH 49. On the basis of the obtained results, suggestions for improving testing procedures are also given.