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Problems concerning total dry weight and distribution of underground phytomass were studied in a pasture trial at Rapotin near Šumperk, the CzechRepublicin the period 1995-1999. The total weight of dry underground pasture phytomass (DUP) was 976 g/m² (5-year average) in a soil layer of 0-200 mm (both live and dead roots). The DUP was significantly increased by mineral fertilizers (90 kg N/ha, 30 kg P/ha a 90 kg K/ha). The weight of DUP was not significantly influenced by a grazing system, renewal or resowing of the original grassland. In unfertilized plots, DUP weight amounted to 989 g/m², i.e. 92 g/m² (8.6%) less than in fertilized plots in the period 1996-1999. In the same period, under the grassland exploited by rotational grazing 1142 and under continuous grazing 1082 g/m² DUP were determined, i.e. by 60 g/m² (5.5%) less. The highest DUP weight in the period 1996-1999 was found in autumn 1997 (1222 g/m2) immediately before achieving the maximum forage yield in May 1998. In a layer of 0-20 mm, 54.6% of the total DUP was found. In this surface layer, significant increase in the DUP weight was found in fertilized plots. In 1999, some 88.5 and 90.2% of DUP were concentrated in unfertilized (903 g/m²) and fertilized (952 g/m²) plots, respectively in a layer of 0-100 mm.

The physiological response to application of elemental sulphur (S) and cadmium (Cd) of maize (Zea mays L.) grown for 60 days in pot soil was studied. The S was added into the soil with 2 rates (0 and 50 mmol/kg) and Cd was added in solution in 4 rates (0, 20, 50, 100 mg/kg). All the S and Cd were added before planting. Shoot biomass decreased with the application of Cd to the soil whether S was applied or not. The application of S and Cd to soil led to an increasing accumulation of Cd in the shoots of maize. The concentration of chlorophyll was reduced significantly in Cd-treated plants with or without supplementary S. The content of malondialdehyde (MDA) was increased significantly in treatments with S and Cd, compared to the control. The activity of peroxidases (POD) was increased but catalase (CAT) was decreased in plants treated with Cd, again with or without S, in comparison with control. POD and CAT activities decreased in all the Cd treated plants with S, as compared to the plants without S. The results suggest that Cd reduces the crop growth, concentration of chlorophyll and activity of CAT, but increases the content of MDA and activity of POD. S supplies decrease the content of MDA, activities of POD and CAT, as compared to zero S supplies at the same rate of Cd application.

Three-year trials were conducted to study germination and emergence of prickly lettuce (Lactuca serriola L.) achenes, increments of shoot dry matter and susceptibility of the weed to selected herbicides. The germination rates of achenes at10°C (92%),20°C (97%) and30°C (95%) did not indicate any significant differences within 20 days from sowing. The highest percentage emergence of prickly lettuce achenes was determined after their sowing into a depth of1 mm. Differences from the variants of sowing onto the soil surface (0 mm), into a depth of 10 and20 mm were significant. There were no differences in the emergence rates from a depth of 10 and20 mm. The highest increments of shoot dry matter were observed when prickly lettuce plants were grown for 4-7 weeks after sowing at20°C. The effect of selected herbicides on prickly lettuce plants treated at the stage of 2-3 true leaves was evaluated on the basis of a change in the content of shoot dry matter. A significant decrease in dry matter against the control was recorded in all variants after herbicide application. The effect (expressed by a lower dry matter content) was significantly higher after the combination amidosulfuron + iodosulfuron-methyl + mefenpyr-diethyl (10 + 2.5 + 25 g/ha) was used than after the application of tribenuron (10.85 g/ha) and picolinafen + cyanazine (120 g + 480 h). The effect of amidosulfuron (22.5 g/ha) was significantly higher than in the variants treated with tribenuron, picloram + clopyralid (16.75 + 66.75 g/ha), clopyralid (90 g/ha) and picolinafen + cyanazine (150 + 600 g/ha). The best effects were produced by herbicides containing amidosulfuron and iodosulfuron as active ingredients.

Four protein fractions: 1 - albumins and globulins, 2 - gliadins, 3 - glutenins (extracted in NaOH), 4 - glutenins (extracted in SDS) separated by SDS-PAGE were used as biochemical markers for evaluation of polymorphism level in three spelt wheat cultivars - Hercule, Altgold and Rouquin, three new-breeders' spelt lines - H92.27, H92.28 and M92.20 (originated from hybridisation between spelt and common wheat) and reference common wheat cultivar Brea. Electrophoretic phenotypes and zymograms were evaluated by means of digital image analysis and Nei and Li coefficient of similarity was used to evaluate the relation of analysed genotypes. Entire evaluation of all four-marker systems showed differences between common wheat cultivarBreaand spelt cultivars and spelt breeders' lines. Also significant differences between old spelt cultivars (Hercule, Altgold and Rouquin) and new spelt breeders' lines were found. The reality of the mutual passing of protein fractions (gliadins and glutenins), based on Osborne extraction was confirmed. In this sense it is necessary to see both fractions as dynamic overlapping structures.

The influence of different fertilizer forms and rates on nitrogen, phosphorus and potassium contents, nitrate accumulation and yield in red head chicory (Cichorium intybus var. foliosum L.) was investigated. Field fertilization trials were set up at two localities inNorthwest Croatia in 1999 and 2000. Trials were laid out according to the Latin square scheme in five fertilization treatments: manure 5 kg/m2, three rates of complex mineral fertilizer NPK (5:20:30) - 50, 100 and 150 g/m2, and an unfertilized control variant. The results of investigations indicate that there were no significant differences between treatments in the plant nitrogen and phosphorus contents. Significant fluctuations of the chicory potassium content (3.27-4.75% K) depending on the fertilization variant were recorded only in 1999 while in 2000 all values (4.13-5.12% K) were uniform. Plant nitrate levels were influenced by weather conditions more significantly than by the form and rates of fertilizers. All the recorded values are within the limits tolerated for leafy vegetables. Comparing the trial years, yields were generally higher in 1999 (1.58-4.95 kg/m2) than in 2000 (0.40-2.70 kg/m2). No significant differences in yield were recorded between the application of stable manure and the lowest mineral fertilizer rate.

The phosphorus (P) availability was tested on hydromorphic soils located in theSavavalley. 480 soil profiles covering the area of31 227 hawas analysed in our study. The plant available P was determined by the Ammonium-Lactate method. The P availability in the surface layer (0-30 cm) is very low (up to 5 mg P2O5/100 g of soil) in about 30% of the tested agricultural land (9 440 ha), next 32% (9 897 ha) is in the range of a low P availability (from 5.1 to 10 mg), while only 17% (5 445 ha) has a good or very good P availability (above 20 mg). Especially high frequency of low P availability was found in vertic gley, amphygley and hypogley soils (total8 680 haor 28% of tested agricultural land).

The interaction of manganese with cadmium (Cd) toxicity was studied on maize plants grown in hydroponics. Manganese supplied as MnSO₄clearly alleviated the toxic effect of cadmium on the root growth of maize seedlings. The magnitude of alleviation was dose dependant and total abolition of 10µM Cd toxicity on root growth was observed at Mn/Cd ratio of 20:1. The 12 h pre-treatment with 10μM Cd was generally toxic for nitrate uptake and reduction (both determined in Cd-free media). The beneficial effect of 100μM Mn on this toxicity was confirmed for the low-affinity nitrate uptake system, but on the other hand, Mn alone seems to be slightly toxic for high affinity nitrate uptake system and on the nitrate reductase activity.

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.

Field experiment demonstrated the benefit resulting from biological soil management including the use of N₂-fixing and growth promoting bacteria A. brasilense B-4485 for long-fibred flax. Seed inoculation by A. brasilense B-4485 was equivalent to the introduction of 15 kg/ha of N that provided the possibility of partial flax N requirement supply. Treatment A. brasilense + N₁₅P₆₀K₉₀ is considered to be the most profitable management in regard to flax yield and its quality, and is comparable to N₃₀P₆₀K₉₀ treatment. Biological management allows preventing high concentrations of N in soil, excludes lodging and negative effects on flax yield and its quality. Implementation of biological management for flax nutrition may be profitable for both ecology and economy of long-fibered flax growing.

The effect of nitrogen fertilization on root length (RL) distribution of winter wheat (Triticum aestivum L.) was investigated. The study was conducted in Prague-Ruzyne on clay loam Chernozemic soil in the years 1996-2003. Two (N0, N1) and three (N0, N1, N2) treatments, unfertilized (N0), fertilized with 100 kg (N1) and 200 kg N/ha (N2) were studied in 1996-2000 and 2001-2003, respectively. Nitrogen rate 100 kg/ha had no effect on RL in soil layers (P > 0.1) in years 1996-2000 and 2002-2003 and there was not significant interaction between N treatment and soil layer except for year 1998 (P < 0.01). Nitrogen fertilization affected RL distribution significantly (P = 0.013) only in 2001 due to reduction of root growth in subsoil layers in treatment N2 (200 kg N/ha) in comparison with N0 and N1. The effect of N fertilization on total RL in rooted soil volume was insignificant. There was a significant effect of year on total RL (P < 0.01) but not of interaction of year and N treatment. Roots reached, with the exception of two years, the depth between 100 and 130 cm. Nitrogen fertilization (N1) had no effect (P = 0.59) on rooting depth (RD) in years 1996-2000 but there was a significant effect of interaction between year and N fertilization on RD (P < 0.01). In the second experimental series (2001-2003) N fertilization rate 200 kg N/ha significantly reduced maximum RD (P < 0.01) in comparison with N0 and N1. The year had highly significant effect on RD.

Microbial activities and counts of microorganisms were monitored as a part of research projects at 11 localities on arable land of different soil types during the years 2002-2006. The counts of microorganisms (total bacteria count, actinomycetes, micromycetes, Azotobacter, oligotrophic and spore-forming bacteria) and microbial activities (respiration, ammonification and nitrification tests) were evaluated using summary statistics, analysis of variance and correlation coefficients. The average counts of microorganisms corresponded with usual counts of microbes in arable soils. There were only some differences among localities in Azotobacter counts. Soil respiration is very often used as an indicator of soil microflora activity. Average values of basal respiration were slightly lower (0.45 mg CO₂ /h per 100 g dry soil) than usual values, potential respiration with glucose (G) or with ammonium and G (NG) responded to usual values (average G 4.27, NG 9.53 mg CO₂ /h per 100 g dry soil). All activities (except actual ammonification) were higher in spring season, but the differences were not significant. There were significant differences in correlation coefficients among the selected criteria; 66% from the total number of correlation coefficients were non-significant, 34% were significant (13% of them was at the significance level 0.05, 10% P < 0.01, and 11% P < 0.001).

The aim of the study was to determine the response of soil enzymes such as dehydrogenases, urease and acid and alkaline phosphatases to heating oil contaminating (0.0, 0.25, 0.5, 0.75, 1.0, 1.5% of soil) the experimental soil supplemented with lime and used for cultivation of yellow lupine of the Markiz variety. An increasing contamination of soil with heating oil stimulated the activity of dehydrogenases and acid and alkaline phosphatases but had a toxic effect on yellow lupine. Lime supplements did not have a significant effect on an average activity of soil dehydrogenases. However, such soil treatment had a significant effect on urease. Increasing heating oil doses in lime-supplemented soil stimulated urease activity, whereas in lime-free soil urease activity was inhibited. The activity of acid and alkaline phosphatase was lower in limed soil than in lime-free soil. The activity of dehydrogenases, urease and alkaline phosphatase in the soil with lupine cultivation was significantly higher than in the unsown soil.

Soil bacteria belonging to the genus Azotobacter, Pantoea and some unidentified soil isolates were tested in vitro for phytohormone production under laboratory and soil conditions. The German wheat variety Munk was inoculated by several soil bacteria with exogenously applied hormones (IAA, 2,4-D) and a flavonoid(naringenin) with a half of the amount of recommended doses of fertilizers under greenhouse conditions. Most of the soil bacteria tested were able to produce indole acetic acid (IAA), and stimulated a lateral root development and colonization by the addition of 2,4-D and IAA. A formation of paranodules on roots as a result of crack entry invasion was observed with 2,4-D as well as with IAA. We were able to reisolate the organism from the paranodules and could establish the same results. Analyses for root exudates and in vitro phytohormone production by various bacterial isolates were also carried out, revealing that 2,4-D can be replaced either by high IAA producing bacteria or by exogenous application of IAA. Bacterial survival in the rhizosphere as well as the root and shoot weight of wheat plants were positively affected also by the addition of IAA, 2,4-D and naringenin.

Effect of sugar beet seed inoculation with a bacterium Pseudomonas fluorescens and treatment by fungicides Thiram 42-S and Dithane S-60 with and without seed inoculation aiming to control Aphanomyces cochlioides - root decay agent was studied. The trial lasted for three years on two soil types (Mollic Gleysols and Eutric Cambisols). The following parameters of sugar beet yield and quality were investigated: root yield, sugar content, sugar in molasses, sugar yield as well as percentage of the infected and decayed plants as a consequence of parasite fungus infestation. The highest average sugar beet root yield was obtained in the variant of the seed treated with fungicide Thiram 42-S and inoculated with bacterium P. fluorescens (85.15 t/ha). However, there were no statistically significant differences (P < 0.05) between the above-mentioned variant and the one with seed inoculated only with bacterium P. fluorescens (84.63 t/ha). The highest mean sugar content of 16.39% was also accomplished during the three-year investigation in the variant of the inoculated seed treated by fungicide Thiram 42-S. All other variants accomplished statistically very significantly lower values of this parameter. The same variant was characterized by the highest mean sugar yield value (12.79 t/ha) on both soil types. Namely, an average sugar yield of the variants inoculated with bacteria was 11.22 t/ha and by 44.22% higher compared to an average yield of non-inoculated variants. The highest percent of the infected and decayed plants (average value on both soil types in the three year investigation) was reported in the control variant (28.92% infected and 25.00% decayed plants) whereas the lowest one was detected in the variant of the seed inoculated with bacterium P. fluorescens in combination with low dose of fungicide Thiram 42-S (4.70% infected plants and 2.88% decayed plants). An average percent of the infected plants inoculated with bacterium P. fluorescens was 9.13% whereas the aforesaid value of the plants infected with parasitic fungus A. cochlioides in non-inoculated variants was by 146.00% higher being 22.42%.

Six wheat varieties/lines and six derived F₂hybrids were studied to ascertain and compare heritability and genetic advance for flag leaf osmotic pressure, flag leaf water potential, flag leaf venation, flag leaf area and flag leaf thickness. Most of these characters had high heritabilities and expected a genetic advance. Prospects of a genetic improvement for all the characters studied are evident. The most promising cross combinations are PASBAN-90 × SARC-5 and SH-2002 × SARC-5. These traits therefore deserve a better attention in future breeding projects for evolving better wheat for stress environments.

Biofertilizers have been used as sources to improve plant nutrients in sustainable agriculture. Experiments were conducted to evaluate the potential of phosphate solubilizing bacteria (PSB) Bacillus megaterium var. phosphaticum and potassium solubilizing bacteria (KSB) Bacillus mucilaginosus inoculated in nutrient limited soil planted with pepper and cucumber. Results showed that rock P and K applied either singly or in combination did not significantly enhance soil availability of P and K, indicating their unsuitability for direct application. PSB was a more potent P-solubilizer than KSB, and co-inoculation of PSB and KSB resulted in consistently higher P and K availability than in the control without bacterial inoculum and without rock material fertilizer. Integrated rock P with inoculation of PSB increased the availability of P and K in soil, the uptake of N, P and K by shoot and root, and the growth of pepper and cucumber. Similar but less pronounced results were obtained when rock K and KSB were added concomitantly. Combined together, rock materials and both bacterial strains consistently increased further mineral availability, uptake and plant growth of pepper and cucumber, suggesting its potential use as fertilizer.

This study was carried out to investigate the effect of treated wastewater on soil chemical and physical properties. Field experiment was conducted in Borkhar region in Isfahan province in central Iran with two water treatments of wastewater and groundwater under sprinkler and surface irrigation systems for three crops of sugar beet, corn and sunflower. Soil samples were collected to 120 cm depth to determine concentration of lead (Pb), manganese (Mn), iron (Fe), cadmium (Cd), nickel (Ni), cobalt (Co), copper (Cu) and zinc (Zn). Irrigation systems had no significant effect on extractable heavy metals in soil. The accumulation of Pb, Mn, Ni and Co in the soil increased significantly in the wastewater treatment as compared to the groundwater treatment. The accumulation of Pb, Mn, Ni, Co, Cu and Zn decreases with the soil depth. Treated wastewater showed no effect on the increase of Fe, Cd, Ni, Cu and Zn during growing season. The irrigation system had a significant effect on infiltration rate, bulk density and total porosity. Under sprinkler irrigation system the infiltration rate increased significantly

The effects of different concentrations of copper (0-800 μmol) on growth, protein contents, peroxidase (POD), catalase (CAT), superoxide dismutase (SOD), and phenylalanine ammonia-lyase (PAL) in Jatropha curcas L. seedlings were assessed by means of pot experiments. Results suggested that increased copper concentrations lead to decreased shoot elongation and seedling biomass. Protein content in the leaves and roots reached their highest levels at the copper concentrations of 400 μmol, while the highest protein content in the stem was observed at 800 μmol copper. POD activity in leaves and stems was unaffected at low copper concentrations, but showed a considerable variation at high copper concentrations. In roots, the highest POD activity was observed at 200 μmol copper. Under copper stress, SOD activity in leaves increased concomitantly with increasing copper up to 400 μmol, and SOD activity in stems and roots showed a slight increase. Catalase activity significantly elevated in leaves and roots but showed no significant changes in stems of the seedlings exposed to copper. A gradual increase of PAL activity in leaves and roots at the copper concentration of 400 and 200 μmol was observed, while PAL activity remained unchanged in stems.

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).

The effect of osmotic stress on oxidative injury, compatible solutes content and water relations was investigated in two maize cultivars (Zea mays L. cv. Ankora - drought-sensitive and cv. Nova - drought-tolerant). Relative water content in leaves of both cultivars decreased after drought treatment, leaf water loss of sensitive cv. Ankora was higher than that of cv. Nova. The 24 h water stress induced by 0.3M sorbitol (-1.4 MPa) resulted in a damage of cell membranes. Lipid peroxidation rose in all studied organs of cv. Ankora and electrolyte leakage in roots of cv. Ankora was much higher than in cv. Nova. Similarly, proline content increased significantly in all studied organs of cv. Ankora. Content of soluble sugars increased in all studied organs of both cultivars, but the mesocotyl of cv. Nova accumulated the highest amount of sugars. The electrolyte leakage was the highest in the roots of both cultivars. Osmotic stress had deep influence predominantly on the roots of both cultivars. It is apparent that stress impact on the drought-sensitive cv. Ankora was deeper than on the drought-tolerant cv. Nova.

The effect of three different growing methods, and plant age on the yield of purple coneflower (Echinacea purpurea L.) Moench., Asteraceae are described. The weight of fresh and dry mass of rhizomes increased significantly with the age of the plants. Independently of the age, the highest yield of rhizomes (1779 g/m² FW - 589 g/m² DW in the third year) was found in the plants grown from root cuttings and the smallest (385 g/m² FW - 108 g/m² DW in the third year) from seeds sown directly into the soil. A similar dependence was obtained in the yield of flower heads. No relation was noticed between the growing method and the flavonoids and polyphenol acids contents neither in the flower heads nor in the rhizomes. The polyphenol acids content was slightly higher in the flower heads (2.85% in the third year) than in the rhizomes (2.22% in the third year). The results demonstrate that the experimental factors can stimulate increased yield of rhizomes and flower heads of E. purpurea.

Uptake of mineral nutrients in chickpea cultivars might be an important response in drought tolerance. An experiment under controlled conditions was carried out to study the genotypic response of 11 chickpea (Cicer arietinum L.) cultivars to drought and its relations with N, P, K, Ca, Mg, Fe, Zn, Mn and B uptake and uptake efficiency. Plants were grown either optimal or drought stress implemented at pre- (early drought stress, EDS) and post-anthesis (late drought stress, LDS) stages. Growth reduction of the cultivars as a response to drought significantly differed. The results of the study indicated that EDS had less detrimental effects on growth and nutrient uptake than LDS conditions. In general, drought tolerant chickpea cultivars accumulated more N, P, K, Ca, Zn, Mn and B in both drought stress treatments except for Zn and Mn uptake in LDS treatment. The total nutrient uptake efficiency of the cultivars were also very significantly correlated with the growth reduction ration (GR) both in EDS and LDS treatments giving correlation coefficients (r) of -7859 and -0.7678, p < 0.01, respectively.

In the years 1999-2003 the effect of covering rows of early potatoes with non-woven fleece on the yield formation, dry matter content in tubers, temperature of soil and of air in ground layer was investigated. Covering of rows enhanced the market yield of tubers at early harvest 60 days after planting in average by 35.8% in comparison with the uncovered control. At harvest 67 days after planting the difference in advantage of the covered variant were 17.2% and 85 days after planting the difference in yield between variants was already non significant. The yield effect of the fleece was affected by year (higher effect in the years with cold spring) and by variety (Impala responded at 60 days after planting by yield increase under fleece 43.7%, Adora 27.9%). Higher dry matter content of tubers by 0.87% was found in covered plants 60 days after planting in comparison with control. Cover enhanced average air temperature in ground layer by 2.0°C, in soil in depth 100 mm by 1.8°C.

Significant quantities of Cd have been added to soils globally due to various anthropogenic activities, posing a serious threat to safe food production and human health. Rhizosphere, as an important interface of soil and plant, plays a significant role in the agro-environmental system. This article presents a review of relationship between root excretion and microorganisms and plant resistance to Cd toxicity and possible mechanisms. Root exudates markedly altered in species and quantity under Cd stress. Root exudates can affect Cd absorption by plants through changing the physical and chemical characteristics of rhizospheres. The influence of root exudates on Cd bioavailability and toxicity may include modifying the rhizosphere pH and Eh, chelating/complexing and depositing with Cd ions, and altering the community construction, the numbers and activities of rhizospheric microbes. In this paper, the methods to reduce the transfer of Cd in soil-plant system by adjusting rhizosphere environment are discussed, and some aspects are also proposed that should be emphasized in the future research work.

Several fusarioid microorganisms were isolated as potential pathogens of hop (Humulus lupulus L.) but their virulence was not proved in inoculation trials in field conditions. Molecular search for other possible pathogens was then performed. Using terminal restriction fragment length polymorphism (TRFLP), Gibberella pulicaris (anamorph: Fusarium sambucinum) was identified as a probable cause of the hop wilting. The primary cause of the disease is wounding of hop crowns by feeding of rosy rustic moth (Hydraecia micacea) caterpillars or by defect pruning and other unfavourable circumstances. The specific primer HLf1 was designed that can be used to detect the pathogen in soil and in damaged plant tissues.

The priority of this study was to investigate how selenium influences toxicity of Cd, Zn, Cu and Pb when the metals appear in the hydroponic solution in pairs. As a model subject mustard seedlings (Sinapis alba L.) were used. Except phytotoxicity of individual metals and Se-metal combinations determined through photosynthetic pigments content (chlorophyll a, b, total carotenoids) also metal accumulation in the roots and shoots was determined by the AAS method. Se in all metal combinations reduced the unfavourable effect of other metals tested for chlorophylls content, however, for carotenoids primarily the opposite effect occurred. For metal accumulation in the roots and shoots it was confirmed that Se stimulated only Cd (about 24%) and slightly Cu (about 9%) accumulation in the roots, while in the shoots there was inhibited accumulation of all metals tested. The strongest inhibition was observed in Pb accumulation (84.9%). This fact indicates that Se generates some barriers for metal transfer from the roots to the underground plant parts. In contrast, Cu, Zn, Pb and Cd increased Se accumulation in the roots in the range of 4 (in combination with Cu) to 68% (in combination with Cd) and in the shoots in the range of 11 (in combination with Pb and Zn) to 44% (in combination with Cd). In the shoots only Cu inhibited Se accumulation (about 67%).

Fertilization with tannery materials positively influenced the soil pH and increased the content of alkaline cations in soil. After four years of investigations organic carbon content decreased most in the soil fertilized with untreated sludge, mineral salts and in the control soil. Irrespective of fertilization used and year of studies cadmium occurred mainly in most mobile fractions (mobile, exchangeable and bound to manganese oxides). Copper was mainly bound in fractions less available to plants. After four years of studies an increase in mobile copper forms was registered in all treatment soils. Lead in the soil was present mainly in the form bound to organic matter and amorphous iron oxides. Distribution of lead points to the small share of this metal in the mobile and exchangeable forms, both immediately after fertilization applied and after four years of studies. Chromium became fixed in fractions less available to plants, mainly bound to iron oxides and in residual fraction. On the other hand, an apparent effect of fertilization with materials of tannery origin on this element total forms content was registered.

Our objective was to determine which rhizome extract from Japanese knotweed, Giant knotweed or Bohemian knotweed has the most significant inhibition effect on the germinated seeds. The seeds of white mustard were incubated with the extracts for two days under laboratory conditions. We monitored differences in number of germinated seeds, length of radicles, hypocotyls and root/shoot ratio between the control and experimental seeds. Inhibitory effect of extracts from dried knotweed rhizomes was confirmed, but without differences among tested plants. A higher allelopathic effect was revealed in the case of extract from aboveground parts.