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Ditylenchus dipsaci, the stem nematode, is a migratory endoparasite of over 500 species of angiosperms. The main method of D. dipsaci control is crop rotation, but the presence of morphologically indistinguishable host races with different host preferences makes rotation generally ineffective. Therefore, a sensitive, rapid, reliable, as well as cost effective technique is needed for identification of D. dipsaci in biological samples. This study describes the development of species-specific pairs of PCR oligonucleotides for detection and identification of the D. dipsaci stem nematode in various plant hosts. Designed DIT-2 primer pair specifically amplified a fragment of 325 bp, while DIT-5 primer pair always produced a fragment of 245 bp in all D. dipsaci isolates. Two developed SCAR primer pairs were further tested using template DNA extracted from a collection of twelve healthy plant hosts; no amplification was however observed. The developed PCR protocol has proved to be quite sensitive and able to specifically detect D. dipsaci in artificially infested plant tissues.

In 1997 and 1998 we used samples of harvested grain to verify the possibility of distinguishing 14 winter wheat genotypes and six triticale genotypes and detecting the impurity on the basis of the detection of polymorphism of prolamin kernel proteins using the methods of the PAGE ISTA. On the basis of the identity index two sister prolamin lines with different percentage of participation, which was based on the weather conditions of the year of harvest, were discovered in seven wheat genotypes (Astella, Brea, Hana, Ilona, Siria, Sofia and Šárka) and two triticale genotypes (Tornádo and KM 779). A foreign genotype was detected in the Hana and Astella varieties. The identity index of the impurity to the Astella and Hana variety (i.e. ii = 0.28 and ii = 0.20, respectively) was considerably lower. In an unknown genotype (impurity) we detected the gliadin block Gld 1B3, which is the genetic marker of rye translocation T1BL.1RS, the Sr31 gene of resistance to black rust, higher cold resistance and the marker of poor baking quality (presence of secalin genes). The results proved the potential practical application of the method of electrophoretic detection of polymorphism of prolamin proteins as markers of impurities of foreign genotypes in a seed sample.

This paper presents the results of a three-year research on the effect of perforated polyethylene foil and polypropylene fibre covering at various lengths of plant cover period (2 and 3 weeks after plant emergence) on the assimilation leaf area of early potato cultivars. In the case of plant covering for 2 weeks after emergence the assimilation leaf area and leaf area index (LAI) at the moment of cover removal were on average 2 times higher than in the cultivation without covering; at the 3-week period of plant covering they were almost 1.7 times higher. A higher favourable effect of covering was obtained in the year with the lowest air temperature in May. The use of the covers at that time increased the assimilation leaf area and LAI 2.5 times and 3 times, respectively. The research showed no significant effect of the type of cover used on the assimilation leaf area and LAI; however, the specific leaf area (SLA) was higher with the use of polypropylene fibre.

Effects of the year, previous crop and control of leaf diseases on grain yield, test weight, protein and starch content, Fusarium head blight (FHB) and deoxynivalenol (DON) content in grain were investigated in four spring barley varieties. The trials were set up in 2001-2004 at Kroměříž (235 m above sea level, average annual temperature 8.7°C, annual precipitation sum 599 mm) in a five-course crop rotation, where spring barley followed the previous crops sugar beet, winter wheat, maize, and oilseed rape. The experimental years differed a lot in temperature and precipitation. The years 2001 and 2002 were dry and warm and grain yield was much lower as compared to that in the following years even though the other growing conditions were identical. The most stable quality parameters were obtained after the previous crop sugar beet. The average value of test weight was 661 g/l(ranging from 629 to 685 g/l), protein content 11.2% (10.3-11.7%) and starch content 61.5% (58.9-64.9%). Grain yield averaged 6.67 t/ha. Test weight after maize was on average 658 g/l(619-692 g/l), protein content 11.5% (10.1-12.4%), starch content 60.7% (59.2-63.8%), and grain yield 6.24 t/ha. Test weight and starch content were lower and protein content higher after oilseed rape and winter wheat. A higher FHB incidence and DON content were found after the previous crop maize. In 2001 and 2002 with strong water deficit during the growing seasons, more grains infected by Fusarium spp. were detected and DON content was higher too. The increase was due to a short rainy period at heading of spring barley. Problems of variable conditions for growing malting varieties of spring barley and current possibilities of producing both good grain yields and quality are discussed.

Market varieties of hops are classified to several groups according to their use in the brewing industry - aroma, bitter (dual-purpose), high-alpha ones. Saaz and other genetically related varieties form a separate group among the aromatic hops. The group called fine aroma hops has a low content of a-bitter acids (3-4% w/w), its content of b-bitter acids is in the range of 4-7% w/w and cohumulone ratio in the interval of 23-26% rel. The composition of hop oils is characterised by the content of b-farnesene in the range of 15-20% rel. and trans-a-bergamotene at the amount of ca. 1% rel. Most market varieties of hops are of hybrid origin. It holds true about the Czech varieties Sládek, Bor, Premiant and Agnus. The content of a-bitter acids in bitter varieties is in the range of 7-10% w/w while the content of a-bitter acids in high-alpha hops is higher than 10% w/w.

Chlorophyll a fluorescence measurements were carried out on two barley (Hordeum vulgare L.) cultivars Arabi Abiad and Arabi Aswad at 8 and 14 days after emergence to identify their early tolerance mechanism for heavy metals (25 and 50μM of cadmium and lead). Transient fluorescence curves (OJIP curves) and energy flux models showed different specific reactions of photosystem II (PSII) of each cultivar to each type of stress. After 7 days of lead stress application plants of cv. A. Aswad showed weaker I and P peaks on the OJIP curve than control plants, and the appearance of a new K step; parameters of phenomenological energy fluxes for cv. A. Abiad were similar to those for control plants and only some silent reaction centers appeared. Generally, parameters of energy fluxes within PSII were directly shifted shortly (24 h) after the application of both heavy metals, especially in the case of plants grown under cadmium treatment. This suggests that these parameters could be good indicators for monitoring of these two pollutants in the environment at early stages of plant development.

Zinc distribution in the main soil fractions and zinc accumulation in potatoes, maize, wheat and barley after different soil treatments (basic sludge rate, triple sludge rate, NPK, NPK + inorganic Zn) were investigated in a field experiment conducted at five localities of the Czech Republic (Červený Újezd, Hněvčeves, Humpolec, Lukavec, Suchdol) with different soil and climatic conditions. Three soil types were investigated in the experiment: clay-loamy Chernozems, loamy Luvisols, clay-loamy Luvisols and two loamy Cambisols. Sequential analyses provided an overview of soil Zn distribution in the following fractions: exchangeable, Fe-Mn oxide, organic and residual ones. The sludge and inorganic Zn addition supported Zn mobility growth and higher Zn retention in Fe-Mn oxides in all tested soils. The influence of the above-mentioned treatments on higher Zn association with soil organic compounds was not explicitly found. Potatoes, wheat and barley accumulated more Zn after its addition into the soils by sludge and inorganic salt. By contrast, Zn content in maize decreased with higher input of Zn into the soil. The highest Zn concentrations were usually observed in plants grown on both Cambisols.

Field experiments were carried out to study effects of zinc application on quality traits of barley in 1994-1996. The treatments were applied as 0 and 23 kg/ha of zinc sulphate and incorporated into soil before sowing. The experimental design was split plot with four replications. Barley genotypes responded differently to zinc application in relation to thousand grains weight, protein content and starch content. A significant increase was determined for thousand grain weight in cultivars Tokak 157/37 and Cumhuriyet 50, for protein content in Orza, Bülbül 89 and Anadolu 86, for starch content in Karatay 94 and Cumhuriyet 50, while a significant decrease has been found for thousand grain weight in Karatay 94 and Obruk 86 and for protein content in Karatay 94, Cumhuriyet 50 and Tarm 92. When feeding and malting quality are considered together, Karatay 94 and Cumhuriyet 50 are the most suitable cultivars for growing in zinc-applied soils of semi arid areas.

The influence of accelerated ageing test (AAT), i.e. of higher temperature and humidity, on the content and composition of phenolic compounds in the grains of five cultivars of wheat (Triticum aestivum L.) was studied in the years 1998 and 1999. Total polyphenols were determined spectrophotometrically by Folin-Ciocalteau's phenolic reagent and free phenolic acids by an HPLC method in control samples and after deterioration treatment (AAT) in the Ebi, Estica, Nela, Samanta and Šárka cultivars. Statistical significance of deterioration treatment, cultivar, cultivation site, and harvest year was proved. Content of total polyphenols increased during deterioration and levels of the individual free phenolic acid changed depending on their structures. Mean contents of total polyphenols varied from 600 to 960 mg/kg of dry matter. The increase caused by the AAT ranged between 0-20%, the greatest mean increase was observed in the cultivar Nela (by 19%). Sinapic acid (as high as 540 mg/kg of dry matter), 3-hydroxy-benzoic acid and 7-hydroxycoumarin were determined as the major phenolic acids and coumarins. A decrease of free phenolic acids containing methoxy groups in their molecules (sinapic and vanillic acids) and an increase of phenolic acids with free hydroxy groups (caffeic and gallic acids) was observed after deterioration treatment. Statistically significant (P ≤ 0.05) effect of AAT on the content of free phenolic acids was observed.

The skin colour of 21 varieties was assessed on a molecular level. Four varieties had yellow skin colour with the genotype constitution a¹a¹, a¹a² or a²a². Seventeen varieties had dominant red colour. Homozygous A¹A¹ constitution was present in 7 varieties, and heterozygous constitution A¹a¹ or A¹a² was found in the rest of the assessed varieties. The S-alleles controlled the incompatibility system of the pistil. Their detection is possible by means of the PCR method on the basis of allele specific primers. Six S-alleles (S1, S2, S3, S5, S7 and S9) were studied in the same collection of 21 diploid Czech varieties. This paper brings new findings on S-allele characterization, because the Czech varieties have not yet been studied on a molecular level. Both types of S-allele were found in 12 varieties. Only one type of S-allele was described in 9 varieties. Simultaneously, the presence of the Vf gene was screened in the collection of 21 Czech apple varieties. Ten varieties with a field resistance against the scab had a heterozygous constitution of the Vf gene. All 11 susceptible varieties were recessive homozygous vfvf.

This paper is aimed to investigate the effects of some terricolous lichens on soil bacteria's growth in natural conditions. It is focused on species of bacteria and also on numbers of colony of soil specimens that were taken from substrates of three different terricolous lichen species. Peltigera rufescens (Weiss) Humb., which has not secondary metabolites, did not show an inhibition effect on soil bacteria. However, Peltigera neckerii Hepp ex Müll. Arg., which has secondary metabolites, has a negative effect on soil bacteria's growth. Besides, it was observed that Cladonia rangiformis Hoffm., which has many kinds of secondary metabolites, has the highest inhibition effect among the studied species. For this reason, we think that in the next researches, it is convenient to investigate elaborately by soil analysis the effect of lichen's secondary metabolites that have an effect on soil mineralization, on soil bacteria's growth.

The effect of N-S fertilizers on the molybdenum content in oilseed rape plants was investigated in precision field trials. Evaluation was carried out on unfertilized control and two treatments of single fertilizer rates in the first spring fertilizer application, using 100 kg N/ha in AN treatment (nitrochalk) and 100 kg N/ha + 50 kg S/ha in ANS treatment (ammonium nitrate and ammonium sulphate). The results confirmed the significance of sulphur fertilization for the winter oilseed rape plant's cultivation technology, even on fertile soils in the CzechRepublic. The control treatment produced a yield of 3.7 t/ha, while in the AN treatment the yield was 49% higher, and the ANS treatment was 60% higher. An antagonistic relationship between the sulphate and molybdenum anions in their absorption by the plants was demonstrated. The molybdenum content in the flowering period of the plants was determined in mg/kg as follows - in the ANS treatment: 0.17 in root, 0.12 in stem, 1.56 in upper leaves, 0.90 in lower leaves, and 1.17 in the flower petals. Higher and statistically more significant molybdenum levels were determined in the AN treatment: 0.21 in the root, 0.19 in the stem, 2.40 in the upper leaves, 1.72 in the lower leaves, and 1.50 mg/kg in the flower petals. The total above-ground biomass of the plants in the flowering period had accumulated molybdenum at 6.06 g/ha in the ANS treatment, and 8.44 g/ha in the AN treatment.

This review is a short introduction to phylogenetic analysis. Phylogenetic analysis allows comprehensive understanding of the origin and evolution of species. Generally, it is possible to construct the phylogenetic trees according to different features and characters (e.g. morphological and anatomical characters, RAPD patterns, FISH patterns, sequences of DNA/RNA and amino acid sequences). The DNA sequences are preferable for phylogenetic analyses of closely related species. On the other hand, the amino acid sequences are used for phylogenetic analyses of more distant relationships. The sequences can be analysed using many computer programs. The methods most often used for phylogenetic analyses are neighbor-joining (NJ), maximum parsimony (MP), maximum likelihood (ML) and Bayesian inference.

In a microplot experiment conducted in 1999 and 2000 on light soil triticale and field beans were grown as sole crops and in the intercrop system. Two pure stand plant densities were established: 200 and 400 plants/m² for triticale and 50 and 100 plants/m² for field beans. Four possible intercropping combinations were obtained by adding densities of both crops. Triticale was a better competitor than field beans in all intercrops resulting in competitive balance index significantly greater than zero. The number of pods per plant of field beans was significantly reduced in all intercropping combinations compared to the pure stands, however quality of grain of the legume was unaffected by competition. Intercrop comprising 200 plants/m² of triticale and 50 plants/m² of field beans was most productive in the experiment but addition 50 more plants/m² of the legume decreased significantly grain yield of intercrop by 16.2%. The results also show that effective triticale-field beans intercrop for light soil may be designed as additive one, based on 400 plants/m² of triticale.

Tilletia controversa and Tilletia caries were specifically detected in wheat plants by PCR using primers TILf (5´-CAC AAG ACT ACG GAG GGG TG-3´) and TILr (5´-CTC CAA GCA ACC TTC TCT TTC-3´). DNAs from uninfected wheat, rye, barley and triticale were not amplified. Natural infection of control plants by other species of fungi as Alternaria spp., Erysiphe graminis and Fusarium spp. proved the specificity of the test because even in this case no unspecific products were formed. This method can be very useful both for seed producers and for state officers checking the seed quality.

The stability of plant nuclear genome is a necessary condition for the faithful transmission of genetic information through cell lineages. When DNA damage occurs due to various impairments, cells start a number of repair processes including ligation of broken chromosomes. As a result, dicentric chromosomes can be formed. Dicentrics are easily detectable as anaphase bridges during following mitosis. Using Arabidopsis as a model plant, we developed a sensitive cytogenetic assay to identify specific chromosomal rearrangements. Here we show Arabidopsis tert^-/- and atm^-/- mutants and their chromosome rearrangements and fusions analysed by fluorescence in situ hybridization (FISH). The method is based on successive rounds of FISH with chromosome-specific probes and the comparison of resulting FISH images.

The objective of the paper was to determine an appropriate concentration of available sulphur in soil for the initial growth of plants. Based on previous researches two methods of soil extraction were used to acquire information on the soil reserve: water extraction (H₂O 1:5, w/v) and extraction in 0.5M ammonium acetate with addition of NH₄F (KVK-UF soil test). Spring barley was used as a test crop to determine the soil reserve of sulphur and its response to sulphur addition to the soil. A collection of 48 samples of topsoil from agriculturally important localities in the CR was made up for this purpose and the parameters of the nutrient status of the soil were remarkably different. A set of soils was used to establish short-time vegetation experiments in a plant growth chamber according to the scheme: A) control - without sulphur application and B) response variant with application of 30 mg S/kg of soil in the form of (NH)₄SO₄; nitrogen in variant A was adjusted by application of NH₄Cl. Index of nutrient efficiency (IE = Y/N where Y = yield and N = nutrient concentration in the plant) and boundary lines of the point field were used to evaluate the efficiency of barley nutrition with sulphur. The efficient soil reserve of sulphur for the soil test H₂O (1:5) when the ICP analytical technique was used was indicated in the range of 8-11 mg S/kg; 6-10 mg S/kg for sulphate detection on a SKALAR analyser. The efficient utilisation of sulphur by barley plants for the KVK-UF soil test was in the range of 7-12 mg S/kg. The conversion of the KVK-UF S-test to the index of soil reserve of sulphur by adding up a variable portion of the CEC value to the value of sulphur determined by the soil test (0.0167CEC + 9.1667) improved the closeness of the relationship between soil and plant.

During the years 1998-2000 soil chemical (C_org, N_t, pH), textural (sand, silt clay) and microbiological (microbial biomass carbon - CMB, microbial extracellular carbon - C_EX, respiration, ammonification, nitrification) characteristics were tested on grassed chernozem [mollisol] after arable land setting-aside. Different harvest management was also tested: black and green fallow, one or two mulching per year, three cuts with plant biomass removal. For the evaluation of the influence of management and plants we have used three main criteria: (1) µg C_MB/g dry soil, (2) ratio CMB/C_org (%), (3) µg C_EX/mg CMB or eight criteria respectively: (4) ratio of measured and model values of C_MB, (5) ratio of measured and model values of C_EX/C_MB, (6) potential respiration with glucose, (7) potential ammonification with peptone and (8) potential nitrification with (NH₄)₂SO₄. According to these criteria, the best harvest management after arable land setting-aside from 5 different systems, which were tested, could be based on one or two mulching per year. It could be stressed that the two mulching was evaluated as the best in sum of dry mass yield (27.5 for mixtures, 20.1 for legumes and 14.2 for grasses - in t/ha/3 years). The use of legumes (Trifolium repens L. - Medicago lupulina L. - Lotus corniculatus L. - Medicago media Pers.) or grasses [Bromus catharticus Vahl - Arrhenatherum elatius (L.) Presl - Festuca pratensis Huds - Dactylis aschersoniana Graebn.] as cover plants was more successful than the use of their mixtures.

A field trial with Bromus catharticus Vahl. cv. Tacit, Arrhenatherum elatius (L.) P. Beauv. ex J.S. et K.B. Presl cv. Median, Festuca pratensis Huds. cv. Otava and Dactylis aschersoniana Graebn. cv. Tosca sown in rows 125 mm, was established in the year 1996 in Prague (chernozem, altitude 281 m a.s.l., average precipitation 472 mm per year, average year temperature 9.3°C). The stands were cut one or three times per year. The mass was removed or once or twice mulched. The share of the botanical species (by weight method), number of present species and agrobotanical groups (grasses, legumes, other dicotyledonous) coverage were measured from the third to the sixth year of vegetation. The results were evaluated by the analysis of variance (Tukey α = 0.05) and by time series analysis (forecasting) by the Statgraphics Plus programme, version 4.0. The species number increased rapidly with the three times cut variant during the four years, from 4 to 25 species, under the other management it was in average from 7 to 14 species, in the sixth year. The highest share of the sown species with the lowest reduction during the years was at Arrhenatherum elatius (41-72% in the sixth year). Bromus catharticus was extinct in the fifth year. The species chosen had a higher importance for conserving of the original botanical composition than the way of harvest. There was the significantly lower ground cover with the variant one cut per year (on average less than 70%). Mulch covered 15-64% of the surface in dependence on the dry mass yield and mulching frequency. The plants coverage was highest on the two or three times harvested variants (75-80%D).

In our work, we focus on the evolutionary studies of sex chromosomes. As model organisms we use several species of the plant genus Silene. An important part of our research is represented by genetic mapping based on the assays of DNA length or sequence polymorphisms. Apart from the other methods we also use the dCAPS method, which is very useful for detection of the sequence polymorphisms (SNPs). This method is unique as it is able to detect SNPs that are not situated in any restriction site; a fundamental principle of this method is usage of primer designed with one or two mismatches that bring into the target sequence the mutation in vicinity of SNP. Using this method, we found out some improvements that can make analyses more cost-effective.

In the case of cadmium transport via soil macropores, the short-term duration of an interaction between the reactive solute in aqueous phase and soil, as well as cadmium precipitation or adsorption on particles < 10-5 m should be taken into account. Two distribution coefficients are proposed for predicting the cadmium transport in a structured soil: the matrix distribution coefficient Kdm, equal to the equilibrium distribution coefficient Kdeq and estimated using the conventional batch technique, and the macropore distribution coefficient KdM, estimated using the modified batch technique. It was found that the conventional approach (using the coefficient Kdeq only) would underestimate a penetration of the part of Cd transported in the macropores about 255-times in the loamy-sand soil in Kalinkovo, 20-times in the loam soil in Macov, and 122-times in the clay soil in Jurová in comparison with the approach proposed in this study.

In 1999, the effect of increasing levels of nitrogen at the initial (13.9 mg.kg^-1) and increased (40 mg.kg^-1) level of watersoluble sulphur (S_wat) was studied in winter rape (cv. Lirajet) grown in pots. A synergetic effect of nitrogen on concentrations of Ca and Mg was demonstrated in the growth stages DC 20-29 and 31-39. Levels of P and K were balanced. In variants with a low content of S_wat in soil to 40 mg.kg^-1 of soil S concentration increased. With the increasing dose of N the content of S decreased from 1.00% to 0.78% and from 0.68% to 0.38% in DC 20-29 and DC 31-39, respectively. An increased level of S in soil changed the ratio N/S. In variants with a natural (i.e. low) content of S in soil, this ratio widened with the increasing dose of N from 8.06 to 25.15 while in variants with an increased level of S in soil it ranged from 3.24 to 5.85 in the growth stage DC 20-29. Increasing doses of N widened the ratio N/P regardless to concentration of S in plants. In individual growth stages the ratio P/S was markedly narrowed by changing contents of S in soil. The highest yields were obtained in the variant with an optimum concentration of all elements in plants and S contents above 0.6% and/or about 0.4% in growth stages DC 20-29 and DC 31-39, respectively. The obtained yields demonstrated a highly significant effect of N and S on seed yields. At a low concentration of sulphur in plants the yield of seed increased only to the dose N₃(i.e. 0.9 g N per pot); thereafter, it gradually decreased. An increased level of S in soil showed a positive effect on seed yields. Higher doses of N widened the ratio straw/seeds from 2.46 to 7.69; at higher levels of S in soil, an opposite trend was observed. In variants with a low content of S the number of branches and pods increased proportionally with increasing doses of N. On the other hand, increased levels of S reduced the number of branches and pods. At a low level of S in soil the total weight of seeds per pod decreased with the increased supply of N from 69.9 mg to 20.4 mg. At increased levels of S the weight of seeds per pod increased from 61.9 mg to 79.8 mg. Results of field experiments in four different localities corroborated a positive effect of S (in interaction with N) on its concentration in plants. The seed yield was significantly increased. In 2000, results from all localities were markedly influenced by climatic conditions; however average results of all experiments showed that S increased seed yields depending on the dose of N by 2.5 and 5.9%. An optimum nutrition of plants with all elements (including S) results in improved utilisation and increased yields.

To answer many questions of evolutionary developmental biology, it is necessary to identify genes which could be responsible for the studied traits. In this review, I have summarised the methods that are currently used to identify these genes. Mainly the PCR-based methods of gene cloning are discussed here, with the special attention given to the comparison of primer design strategies and PCR amplification strategies. In addition to the review of methods used by other authors, an overview of our experience with PCR-based gene cloning in dioecious model plant species Silene latifolia is included.

The set of 102 samples of agricultural soils was taken for the study of the load of agricultural soils with polychlorinated dibenzo-p-dioxins and dibenzofuranes (PCDDs/Fs). The background value of PCDDs/Fs in agricultural soils of theCzech Republicwas determined. The soils with different sources of the load of PCDDs/Fs were compared. It was concluded that fluvisols in fluvial zones and soils with long-term sludge application are soils with the highest contents of PCDDs/Fs. The soils affected by imission outputs show a lower intensity of the load with PCDDs/Fs that is characterised by higher content of toxic congeners.

A simple method for identification and characterization of telomere-binding proteins is described in this article. After Sodium Dodecyl Sulphate-Polyacrylamide gel electrophoresis (SDS-PAGE), proteins are eluted, renatured and used for retardation analysis with labelled oligonucleotides corresponding to human and plant of telomeric sequences. We show here that this method is efficient to recover sequence-specific DNA-binding abilities of putative telomere-binding proteins.

This paper deals with the recent sissoo (Dalbergia sissoo Roxb.) decline in the plain land (locally called as terai) of Nepal. This study has made an attempt to find the possible causal factor of this decline. The study has made some initiative in this aspect and has made a comparative study of 30 different sissoo forest (both natural and plantation) stands. The symptoms of the sissoo decline were found to be varied. But in most of cases, the top dying of crown was found to be the most prevalent. The top dying starts from the top of the tree and progressively proceeds downwards to the stem. The leaves become yellow. Until now, it has been assumed that only the plantation forests have been affected but this study observed the sissoo decline also in natural forest sites. We analysed various components of physical soil characteristics and we did not find any correlation between the physical soil factors and the sissoo decline. We concluded from this study that the soil is not the sole responsible factor involved in the sissoo decline Furthermore, this paper discusses various aspects of the sissoo decline and possible causal factors concerned. Finally, future management strategies regarding the sissoo management are suggested.

The development of soil limiting values of the protection of the quantity and mainly quality of the crop production tends from empiric values towards critical values, based on ecotoxicity. We present an attempt to derive transfer functions by the means of multiple regression analysis. The substitution of trace elements contents in crops in the prediction equations for fodder or food standards or phytotoxicity limits satisfies the present ecotoxicological demands. We preferred polyfactor relations to simple ones. The exceeding of reference values must be verified by the determination of the hazardous transfer in the field. Therefore the reference values are called testing values. They were derived especially for Cd, Pb, As, Cu, Zn, Ni and Mn. For some trace elements, only protective values can be set up (especially for Cr, Hg, but also for Tl, Be, V). They reflect minimum values that guarantee growing crops without any risks. Experimental data (pot trials) were compared with results obtained in field investigations. The resulting critical values were also compared with the values proposed in Germany.

The lack of recombination in some genomic regions represents a serious obstacle in mapping studies. In this review, we describe methods that are currently used to overcome this problem. Main attention is given to the comparison of methods that are based on the principle of radiation hybrid mapping. We also discuss a strategy called HAPPY mapping (mapping based on the analysis of approximately HAPloid DNA samples using the PolYmerase chain reaction). In addition to reviewing the methods used by other authors, we also summarize our experience with deletion mapping of Y-chromosome in dioecious model plant species (Silene latifolia).

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.