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Our study focuses on the phosphorus (P) balance in two long-term fertilization experiments which were carried out in characteristic soils of Hungary with four fertilization treatments and four main crops. The objectives of this study are: (1) to quantify the P accumulation rate in the upper soil layers and (2) to calibrate and validate the P-balance module of the 4M crop model. The concentration of ammonium-lactate soluble P (AL-P) increased with time in both soils. The mean AL-P accumulation rates in the 0-20, 20-40 and 40-60 cm soil layers were 3.7, 0.7, 0.1 and 3.7, 4.3, 0.6 mg/kg/year in the chernozem and the sandy soil, respectively. The P accumulation rates in the top layers (0-20 cm) changed significantly in time as these gradually decreased from around 6.5 mg/kg/year to zero in about 26 years in both soils. The model results of the phosphorus content in different soil layers, as well as the plant phosphorus uptake were in good agreement with the observed values.

The use of switchgrass (Panicum virgatum L.) as an energy crop has gained great importance in past two decades due to its high biomass yields on marginal lands with low agricultural inputs and low maintenance requirements. Information on the allocation of photosynthetically fixed C in the switchgrass-soil system is important to understand the C flow and to quantify the sequestration of C in soils. The allocation of ¹³C labeled photosynthates in shoot, root, soil, and in microbial biomass carbon (MBC) of rhizosphere and bulk soil of 45 days old, greenhouse grown-switchgrass was examined during 20 days ¹³C-CO₂ pulse labeling period. The total ¹³C recovered in the plant-soil system varied from 79% after 1 day to 42% after 20 days of labeling. After labeling, 54%, 40%, and 6% excess ¹³C resided in shoot, root and soil, respectively on day 1; 27%, 61% and 11%, respectively on day 5 and 20%, 63% and 17%, respectively day 20 after labeling. The maximum incorporation of ¹³C from roots into the MB of rhizosphere soil occurred within the first 24 h of labeling. The excess ¹³C values of rhizosphere soil and rhizosphere MBC were significantly higher than excess ¹³C values of bulk soil and the bulk soil MBC, respectively. The proportion of excess ¹³C in soil as MBC declined from 92 to 15% in rhizosphere soil and from 79 to 18% in bulk soil, for 1 day and 20 days after labeling, respectively. The present study showed the effectiveness of ¹³C labeling to examine the fate of recently photosynthesized C in soil-plant (switchgrass) system and dynamics of MBC.

One of cereal diseases that has gained a greater importance for growers, processing industry as well as for breeders in many regions of the world is Fusarium head blight (FHB) caused by fungi of the Fusarium genus. The objectives of this study were to test diversity among spring barley breeding lines exhibiting various sensitivity to FHB and to find RAPD markers and AFLP markers that will distinguish between susceptible and resistant and/or moderately resistant genotypes. A test of a set of spring barley genotypes artificially infected by fusaria in field trials was carried out. Based on the results from field and laboratory evaluation and deoxynivalenol (DON) content assessment, barley genotypes with different responses to FHB were selected. The genotypes were hybridized and doubled haploid (DH) lines were derived in F₁ generation using the in vitro androgenesis method. Initial parental components and derived DH lines were tested for FHB infection and DON content. A set of parental genotypes of spring barley was tested with 80 RAPD markers. A RAPD marker (H30) was detected which enabled to distinguish between very susceptible parental genotypes and other resistant or moderately resistant spring barley genotypes based on the fragment of about 1300 bp. This specific product was screened in 23 DH lines derived from crosses of parental genotypes of spring barley and detected in 10 DH lines. During the study, some DH lines were selected that exhibited improved resistance to Fusarium infection. A low infection level and low DON content was found in the line DH 4/2 derived from CI 4196 × Foster. The AFLP technique was used to analyse parental genotypes of spring barley. The detected markers can be further evaluated and employed to select breeding materials.

The adverse effect of the application of phosphorus (P) on arsenic (As) adsorption by soils can result in increasing mobility and availability of As. However, in different soils, P might influence As adsorption differently. In this study, the arsenate [As^(V)] adsorption capacities of six soils with different properties and the effects of P application were studied. The results indicated that the adsorbed As^(V) contents all increased as a function of the As^(V) content in equilibrium. When analysed using the Langmuir and Freundlich equations, the maximum As^(V) adsorption capacity of 0.72 mg/g was found for an Alumi-Plinthic Acrisol, while the minimum capacity of 0.09 mg/g was observed for an Epigleyic Cambisol. The adverse effects of P application on As^(V) adsorption by the six soils were observed to be variable. When the P/As molar ratio in a culture experiment was increased from 0 to 10, the maximal and minimal decreases in the As^(V) adsorption capacity of 0.086 and 0.014 mg/g were found in the Alumi-Plinthic Acrisol and Epigleyic Cambisol, respectively. P was relatively more effective in competing for adsorption sites with As^(V) in the Alumi-Plinthic Acrisol and Luvi-Endogleyic Phaeozem due to their higher A/P values (decrease in adsorbedAs/added P) of 1.143 and 1.135, respectively. These results will help decrease the environmental risk of some As-contaminated agricultural soils through the controlled application of P.

Little attention has been paid to the effect of long-term fertilizer application on concentrations of elements in grain of barley produced on the metal non-contaminated agricultural soil. In 2010, we analyzed yield and concentrations of elements in grain of spring barley in unfertilized control, mineral fertilizer application (N₄P₂K₂ - 70, 60 and100 kg N, P and K per ha) and combinations of farmyard manure or poultry litter with mineral fertilizer (FMN₄P₂K₂ and PLN₄P₂K₂) treatments in the Ruzyně Fertilizer Experiment established on Luvisol in 1955 in Prague (Czech Republic). The yield of grain ranged from 4.03 to 9.74 t/ha in the control and FMN₄P₂K₂ treatment. There was a positive effect of fertilizer application on concentrations of nitrogen, phosphorusand potassium, but no effect on concentrations of calcium and magnesium. With the exception of iron, concentrations of micro (copper and zinc) and risk elements (arsenic, cadmium, chromium, lead, manganese and nickel) were not significantly affected by the fertilizer treatments. Long-term use of organic and mineral fertilizers with appropriate application rates does not represent any risk for contamination of barley grain by risk elements on mineral rich and metal non-contaminated agricultural soils.

Using a pot experiment with slightly acidic and alkaline soils anthropogenically contaminated by As, Cd, Pb, and Zn, we assessed how the establishment of Bryum argenteum and concentrations of elements (P, Ca, Mg, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in its biomass are affected by the pH of the substrate, mobility of trace elements, and by quick lime (CaO) and superphosphate (P) additives. Over one vegetation season, in pots naturally colonised by B. argenteum, a substantially higher cover of B. argenteum was recorded on acidic soil that was heavily contaminated with Cd, Pb, and Zn than on alkaline soil with higher As but lower Cd, Pb, and Zn mobility. In acidic soil, the establishment of B. argenteum was substantially improved by CaO additive, which reduced the mobility of Zn and Cd, and by P additive, which improved the P nutritional status and reduced the extremely high concentrations of many elements (As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in its biomass. Although B. argenteum can be used for the monitoring of soil contamination, concentrations of trace elements in its biomass must be evaluated with caution as they can be affected by total and mobile concentrations of elements in the substrate, and by other soil chemical properties.

Gaeumannomyces graminis var. tritici causes take-all disease, the most important root disease of cereal plants. Cereal plants are able to form a symbiotic association with soil-borne arbuscular mycorrhizal fungi which can provide bioprotection against soil-borne fungal pathogens. However, the bioprotective effect of arbuscular mycorrhizal fungi against soil-borne fungal pathogens might vary. In the present study we tested the systemic bioprotective effect of the arbuscular mycorrhizal fungi Glomus mosseae, Glomus intraradices and Gigaspora rosea against the soil-borne fungal pathogen Gaeumannomyces graminis var. tritici in a barley split-root system. Glomus intraradices, Glomus mosseae and Gigaspora rosea colonized the split-root system of barley plants at different levels; however, all arbuscular mycorrhizal fungi clearly reduced the level of root lesions due to the pathogen Gaeumannomyces graminis. Our data indicate that some arbuscular mycorrhizal fungi need high root colonization rates to protect plants against fungal pathogens, whereas others act already at low root colonization rates.

Machines without satellite navigation in fields have a tendency to pass-to-pass errors, especially unwanted overlaps, resulting in waste of fuel and pesticides, longer working times and also environmental damage. This paper evaluates the accuracy of individual machinery passes in fields. Real pass-to-pass errors (omissions and overlaps) in a field were measured on different tractor-implement units with and without guidance system utilization and a comparison between observed guidance arrangements was made regarding final working accuracy and possible benefits from navigation utilization. Additionally, intensity of machinery passes, and repeated passes on soil, as a possible risk for soil compaction in fields, were monitored. The outcomes from our measurements revealed a statistically significant difference between the total area treated by machinery without any guidance system and machinery using precise guidance systems. Concerning the intensity of traffic in fields, it was found out that more than 86% of the total field area was run-over at least once during one cropping season when using conventional tillage practice. The usage of guidance systems can reduce machinery traffic in field to some extent as well and thus improve soil conditions.

Spatial variability of total soil nitrogen and sulphur content has been observed in two plots (I - 54 ha and II - 32 ha). Soil samples were taken from the topsoil in a regular grid, which was localised by GPS (individual sampling points were 80 m apart); subsequently total soil N and S contents were analysed. The average N content in plot I was 0.16%; in plot II it was 0.12%. The content of S in plots I and II was 0.09% and 0.08%, respectively. Spatial variability of total N differed in separate parts of the plots. A higher variability was recorded in plot I, where the coefficient of variation (CV) was 15.7%, whereas in plot II it was only 11.1%. However, sulphur showed only little variability, and thus its coefficient of variation was low (2.5 a 2.3% in plots I and II, respectively). A positive and mostly conclusive relationship has been observed between the N content of soil and the crop yield. This effect was more significant in plot II. The S content in soil showed no correlation with yield. Furthermore, positive correlations were observed between field altitude, soil moisture and crop yield in both plots.

Non-destructive and rapid monitoring methods for crude protein content (CPC) in rice grain are of significance in nitrogen diagnosis and grain quality monitoring, and in enhancing nutritional management and use efficiency. In this study, CPC and canopy spectra in rice were measured based on rice field experiment. Key spectral bands were selected by principal component analysis (PCA) method, and the predicted models were built by multiple linear regressions (MLR), artificial neural network (ANN) and partial least squares regression (PLSR). The results showed that there is a significant correlation between CPC content and key spectral bands. The results of prediction for the three models were in order of PLSR > ANN > MLR with correlation values of 0.96, 0.92 and 0.90, respectively, for the validation data. Therefore, it is implied that CPC in rice (grain quality) could be estimated by canopy spectral data.

Fast-growing woody plants that can be grown under short-rotation systems offer an alternative to food production on arable land, and serve as a potential source of renewable energy. In order to establish the feasibility of future large scale production under the conditions of the Czech-Moravian highland, a high density experimental field plantation including a range of available clones of Populus sp. and Salix sp. with the total area of 1.5 ha was established in early 2001 in Domanínek (Czech Republic, 49°32'N, 16°15'E and altitude 530 m). The clone experiment of Populus sp. covered 0.3 ha in the center of the plantation and included 13 clones in total, with hardwood cuttings of only 6 clones available in numbers allowing 4-replicate experiment. The plantation was established on agricultural land and the trees were planted in a double row design with a density of 10 000 trees/ha. The trial was weeded by mechanical methods, and no irrigation, fertilization, or herbicides were applied. The experiment site was harvested at the end of 2006. It was found that the biomass yields of the tested clones of Populus sp. were in the higher range of results from national and European studies in case of hybrid clones. The satisfactory survival rate in the first year, when mortality tends to be highest, was supported by relatively wet weather conditions after plantation establishment. At the end of the first rotation, the highest yields were obtained from clones J-105 and J-104 (P. nigra × P. maximowiczii) and P-494 (P. maximowiczii × P. berolinensis) with J-105 showing a mean annual increment of dry matter close to 14 t/ha. Additional experiments seem to suggest that well managed poplar plantation might produce even better values if higher survival rates can be achieved.

N-fertilization type affected differently tomato growth. In the field experiment, hydroponic cultures were conducted using NO₃-N (5 mmol); mixture of KNO₃-N (3 mmol) and (NH₄)₂SO₄-N (2 mmol); NH₄⁺-N (5 mmol) or urea (5 mmol) as nitrogen source. Compared to nitrate, ammonium and urea had negative effects on morphology and dry matter production. Effects of the different nitrogen forms were investigated by measuring several photosynthesis parameters and chl a fluorescence. Two different significant types of reaction were found. When nitrogen was added as ammonium or urea, dry weight, chlorophyll tenor, transpiration rate, stomatal conductance and photosynthetic activity were inhibited. Supply of ammonium or urea, reduced the ratio (F_v/F_m), photochemical quenching and enhanced the non photochemical quenching. These data suggest that the adverse decrease in tomato growth under ammonium or urea supply may be related principally to inhibition of net photosynthesis activity. The high non photochemical quenching shown in tomato fed with ammonium or urea indicated that PS II was the inhibitory site of NH₄⁺-N which was directly uptaken by roots, or librated via urea hydrolysis cycle.

Small plot trials were carried out in years 2001-2003 with sugar beet. In the treatment without weed control, dry weight of sugar beet top and LAI of sugar beet were very low (approx. 50 g/m² and 0.5 m²/m², respectively). Yield loss of sugar beet was 80-93%. Dominant weeds were Chenopodium album, Fumaria officinalis and Galium aparine. In the treatments where weeds were removed (by hand) until 4 leaf stage of sugar beet, dry weight of sugar beet top and LAI of sugar beet at first increased normally, but were markedly decreased from the half of the vegetation period. Yield loss of sugar beet was 54-28%. Dominant weed in this treatment was Amaranthus retroflexus. The development of sugar beet top dry weight and LAI of sugar beet was practically identical in the treatments where weeds were removed until 8-10 leaf stage of the crop and in those where weeds were removed during the whole vegetation period (500-900 g/m², or 4-7 m²/m², respectively). No yield loss of sugar beet was recorded. Dry weight of weeds did not exceed 30 g/m² and LAI 0.1 m²/m². A. retroflexus and Mercurialis annua were the most frequent weeds in this treatment.

Fruit quality attributes were studied for two consecutive years in seven blackberry cultivars grown in a Serbian climate and on acidic soil. Physical parameters [berry weight (BW), size and shape] and chemical parameters [soluble solids content (SSC), acidity, total phenolic (TPH) and flavonoid content (TFC) and total antioxidant capacity (TAC)] were evaluated. A high variability was found in the set of the evaluated blackberry cultivars and significant differences were found among them in all studied quality attributes. Year-by-year variations were observed for all quality traits, except berry length (L) and berry shape index (BSI). A high correlation was found among TPH and TAC. In addition, most of cultivars had good adaptation capability and respectable fruit quality attributes, and also had good potential as a commercial crop for fresh and processing markets and future breeding programs.

The main aim of this study was to determine the intensity of hydrophobic/hydrophilic components of the soil's organic matter as well as its hydrophobicity. Non-destructive Fourier Transform Infrared (FTIR) spectroscopy was used for the diagnosis and characterization of the basic classes of the chemical groups (hydrophilic and hydrophobic components) from which the organic matter in the soils is formed. Soil samples (depth 0-30 cm) were taken from the topsoil of the 70 sampling sites from the experimental field at Prague-Ruzyne (Czech Republic) during 2007-2009, where a conventional soil tillage technology was used. It was found that the variability of the intensity of the hydrophobic components is greater (27.6%) than that of the intensity of the hydrophilic components (6.2%), which correlated significantly with the C_org (r = 0.58; P < 0.05) and N_t (r = 0.65; P < 0.05) in the soil. It was proven that the soil samples with a higher proportion of coarse grains are more hydrophobic than those with higher proportions of clay. Data about soil hydrophobicity can help to evaluate the soil quality parameters as well as the soil fertility.

Grazing-induced variations in vegetation may either accelerate or reduce soil carbon storage through changes in litter quantity and quality. Here, a three-year field study (2005-2007) was conducted in Tibetan alpine meadow to address the responses of surface soil (0-15 cm) organic carbon (SOC) storage in the plant growing season (from May to September) to varying grazing intensity (represented by the residual aboveground biomass, with G₀, G₁, G₂, and G₃ standing for 100%, 66%, 55%, and 30% biomass residual, respectively), and to explore whether grazing-induced vegetation changes depress or facilitate SOC storage. Our results showed that: (i) Higher grazing intensity resulted in lower biomass of grasses and sedges, lower root biomass, and in a change in plant community composition from palatable grasses and sedges to less palatable forbs. (ii) Increased grazing reduced the SOC content and storage with only G₃ showing an SOC loss during the plant growing season. (iii) Soil organic carbon storage exhibited a highly positive correlation with the residual aboveground biomass and root biomass. Our results imply that a grazing-induced reduction in plant biomass productivity and changes in species composition would depress soil carbon storage, and that an increase in grazing pressure can lead to a gradual change of alpine meadow soils from being 'carbon sinks' to become 'carbon sources'.

The aim of this study was to investigate the impact of used technology and environmental condition on lucerne dry matter yield in the regional conditions. During a three year period (2011-2013), the investigation was based on management survey in 27 farms in the Czech Republic. Climate conditions significantly influenced yield in some interaction with soil where only combination of dry climate and less fertile soil conditions reduced forage yield. The single soil effect was not significant for forage yield. Applied technology was influenced by both environment and farm characteristic (such as farm size and cow's milk performance) which together significantly explained about 40% of variability of used technological properties. From all investigated technological properties, only cultivation of lucerne in mixture with grasses consistently increased forage yield therefore should be considered as important factor for modelling forage farm yield in the regional conditions.

The present investigation was undertaken to find out efficient strains of arbuscular mycorrhiza (AM fungi) alone or in combinations with Trichoderma viride for inoculation Dendrocalamus strictus L. seedlings. The inoculated seedlings showed good response having higher plant height, phosphorous ions content in root and shoot, AM spore number and root colonization than non-inoculated (control) seedlings in both single (alone) and co-inoculation (combined consortium) experiments. T. viride showed significant growth followed by Glomus mosseae, G. fasciculatum and mixed AM with single inoculation. In co-inoculation, the best growth responses were observed with G. fasciculatum + T. viride followed by G. mosseae + T. viride, mixed vesicular arbuscular mycorrhizas (VAM) + T. viride, G. mosseae + G. fasciculatum + T. viride + mixed VAM, G. mosseae + G. fasciculatum + T. viride and G. mosseae + G. fasciculatum after 120 days and also depicted maximum increase in phosphorus content of shoot and root when compared with other inoculated seedlings. However, all the inoculated seedlings showed significant increase in phosphorus content when compared with control seedlings.

The effects of mineral and organic fertilization on the contents of Fe, Cu, Zn, Mn, B and Mo in soil and in the soil solution as well as on availability of these elements for crops were investigated in the long-term field trial. The highest contents of Zn, Fe, Mn and Cu in soil and soil solution were observed in the treatment with the lowest pH (NPK). In this same combination the content of B and Mo was the lowest. The concentration of Zn, B and Fe in the soil solution significantly increased under farmyard manure application. Liming significantly decreased contents extractable by 1 mol/L HCl forms of Mn and Zn and significantly increase the content of Mo in the soil. Regardless of fertilization applied, microelement concentrations in the soil solution are sufficient for fulfilling nutritional needs of plants cultivated during the trial.

The article presents the possibilities of visual and statistical outputs from the telemetric tracking of game: activity data, heat map, home regions, movement routes and the points of occurrence. Nowadays the methods of the telemetric tracking of game are also used for finding the best ways to eliminate damage caused by wild boar generally, and field crops damage specifically. From telemetrically gained data it is possible to study the local habits of wild boar and their preference of crops and cultivars in various periods. On the basis of this knowledge it is possible to implement the necessary agrotechnical measures. The pilot processing and verification is run on the portal Zvěř (game) online (http://zver.agris.cz/). Currently there are 11 wild boars marked and tracked. The public part of portal is used for the basic presentation of data; in the non-public part the data of private subjects (agricultural companies and hunting organizations) that are not interested in public presentation are processed in the same way. In this way there is at disposal an integral system of wild boar tracking: capturing, marking, data collection, processing and presentation. This system can be used by research institutions, farmers and hunters.

In the paper, the results of the long-term field experiment on soil depletion from potassium on yields and selected indices of nitrogen use efficiency of maize and spring barley were presented. The factors of the experiment were potassium fertilization (K plus and K minus treatment) and increasing nitrogen rates. Maize responded for soil exhausting from K in yield reduction over all the range of nitrogen rates applied in the experiment, and spring barley only through the highest rates. The greater values of nitrogen use efficiency indices were proven for barley as compared with maize. Potassium fertilization slightly increased agronomic efficiency and physiological efficiency of barley.

Field experiments were conducted at two different locations (Barani Agricultural Research Institute Chakwal and farm field Talagang, district Chakwal) for two crop-growing seasons in northern rainfed Punjab, Pakistan to assess the yield and micronutrient uptake of chickpea (Cicer arietinum). The treatments were four combinations of two levels of sulfur (15 and 30 kg/ha) from two sources (gypsum and ammonium sulfate) and a no-sulfur control. Application of sulfur resulted in a significant increase in seed yield up to 17% over control. Ammonium sulfate was a more efficient source of sulfur as compared to gypsum at both the locations. Sulfur application resulted in a significant increase in micronutrient uptake by plant; however effect of sulfur application on soil pH at the end of experiment was not significant. Availability of soil zinc and copper increased with sulfur application at the end of two year experiment. Tissue copper and iron and soil available copper and iron correlated negatively with soil pH. Sulfur should be applied to chickpea grown under rainfed conditions in order to increase seed yield, to improve nutritional composition of product and to enhance efficiency of other fertilizers.

The purpose of the studies was to determine the species composition of fungi and their antagonistic effect towards soil-borne plant pathogens after the cultivation of oats, spring vetch and tansy phacelia as intercrop cover plants. The total population of fungi in the soil after the cultivation of oats was twice as low as after the cultivation of tansy phacelia. A little smaller fungi population was obtained as a result of mulching the soil with spring vetch in comparison to that after the cultivation of tansy phacelia. The proportion of Fusarium spp., Alternaria alternata, Pythium irregulare and Thanatephorus cucumeris isolated from the soil after the cultivation of oats was the lowest one, while being a little higher after the cultivation of spring vetch, and the highest after tansy phacelia. The greatest number of antagonistic fungi occurred in the soil after ploughing in the mulch of oats. Antagonistic fungi isolated from the soil mulched with oats were the most effective in limiting the growth and development of A. alternata, Fusarium culmorum, F. oxysporum, Haematonectria haematococca, P. irregulare and T. cucumeris since the value of their antagonistic effect was the largest. The lowest antagonistic activity of fungi was found out after using tancy phacelia.

Tested soils (1991-2002) were defined by chemical, textural and microbial characteristics. From the tests which describe cambisols, the following parameters have to be stressed. The higher level of C_org (1.20-1.76%), which resulted in quite high microbial biomass carbon content (396-625 µg/g dry soil), high control respiration (0.45-0.80 mg CO₂/h/100 g dry soil) and potential nitrification with (NH₄)₂SO₄ (6.7-18.4 mg N-NO₃/8 days/100 g dry soil). Studied luvisols reached typical levels: C_org (0.97-1.22%), C_MB (398-503 µg/g dry soil), control respiration (0.46-0.57 mg CO₂/h/100 g dry soil), potential nitrification with (NH₄)₂SO₄ (3.2-9.9 mg N-NO₃/8 days/100 g dry soil). Lower levels of organic carbon and a medium level of microbial biomass raised in higher ratio C_MB/C_org (average 4.0%). Highly significant differences (p < 0.01) between cambisols and luvisols were determined for C_org, N_t, pH(KCl), C_MB, C_MB/C_org, C_E, control respiration and potential nitrification, while the difference in potential ammonification with peptone was at level p < 0.05. With the exemption of ratio C_MB/C_org all cambisol characteristics were higher than luvisol ones. Studied soils were evaluated by six biological criteria (C_MB; ratios: C_MB/C_org, C_E/C_MB, potential/control respiration, potential/control ammonification, potential/control nitrification). These criteria distinguished tested soils into three groups. The first one includes two localities in the mountain region (Červená Voda 809, 810; altitude 565-590 m) defined as stagnic cambisols with higher content of C_org (1.40, respective 1.76%) and simultaneously with the highest biomass of micro-organisms from all tested soils (C_MB,625, respective 621 µg/g dry soil). It is not surprising that microbial activities (respiration, nitrification) at these localities were also high. The majority of the studied localities (one eutric cambisol and four luvisols) belongs to the medium group. The third group includes two localities (Neumětely - haplic luvisol, Čistá u Rakovníka - eutric cambisol) where biological criteria was mostly the worst. In the period 1993-2002 microbial biomass carbon was for both sites in the range of 357-458 µg/g dry soil which are not so bad values, but in comparison with localities in mountain wet region they are low. This status was issued in the lower ratio C_MB/C_org (2.71-3.77%).

The experiments were conducted to study the effects of arsenic-contaminated irrigation water, zinc and organic matter on the mobilization of arsenic in an Aeric Endoaquept in relation to rice (cv. IET 4786). The results show that the amount of extractable arsenic increased with the progress of submergence decreased with zinc application. The magnitude of such decrease varied with the Zn amount, being greater (0.70 to 1.08 mg/kg) in the treatment where zinc was applied at the rate of 20 mg/kg. With regards to organic matter application, the arsenic content in soil markedly decreased, especially with farmyard manure application. The results of the greenhouse experiment with exposure of graded doses of arsenic to rice suggest that the upper toxic limit of arsenic in soil was 10 mg/kg for rice. The results of the field experiment show that the grain yield of continuous flooding (4.84 t/ha) and intermittent flooding up to 40 days after transplanting followed by continuous flooding (4.83 t/ha) with the application of ZnSO₄ at the rate of 25 kg/ha did not vary significantly. The lowest grain yield (3.65 t/ha) was recorded in the treatment where the intermittent flooding was maintained throughout the growth period without the application of zinc. The amount of arsenic was, however, much lower in the treatment where intermittent flooding was maintained throughout the growing period combined with zinc sulphate application.

The effects of phosphate solubilizing bacterium (Bacillus FS-3) application on phosphorus contents of tomato (Lycopersicon esculentum L.) plant, growing performance and phosphorus forms in soil were evaluated under greenhouse condition. Five different phosphorus fertilizer treatments (normal superphosphate, triple superphosphate, di-ammonium phosphate, phosphoric acid, and rock phosphate) with and without bacterium (Bacillus FS-3) were applied in pots as 344 kg P/ha. Basal fertilizers were applied to all the pots as 180 kg N/ha (NH₄NO₃ 33% N), 100 kg K/ha (K₂SO₄ 50% K₂O). The results obtained showed that phosphorus availability from soil increased with phosphate solubilizing bacterium (PSB) application. The amount of plant available form of soil phosphorus fraction (resin-Pi + NaHCO₃-Pi + NaHCO₃-Po + NaOH-Pi + NaOH-Po) increased with PSB application. In all fertilizer types, bacteria application converted approximately 20% of less available phosphorus into labile forms. Statistically significant differences were obtained in shoot and root dry weight of tomato plants treated with PSB application. In all of the fertilizers, plant shoot and root weight and P uptake were greater with PSB applications than without PSB. The highest shoot-root dry weight and P uptake of plant were determined in triple superphosphate (TSP) with PSB application treatment. The data in the present study suggest that the application of PSB (FS-3) may increase the availability of soluble phosphate by dissolving the inorganic forms of phosphate and that bacterial strain tested in this study has a potential to be used as a bio-fertilizer in sustainable and organic agriculture.

A 10-20% decrease in annual precipitation is predicted in the Mediterranean basin, and in particular to the Iberian Peninsula, with foreseen effects on the exchange of soil-atmosphere greenhouse gases (GHGs; CO₂, CH₄, and N₂O). To simulate this scenario, we setup an experimental design in the particularly dry period of 2008-2009 using rainfall exclusion and irrigation, to obtain plots receiving 110% (538 mm), 100% (493 mm) and 74% (365 mm) of the natural precipitation. Soil CO₂ fluxes showed a strong increase from summer to autumn as a consequence of increasing soil heterotrophic respiration that resulted from rewetting. Fluxes of N₂O were negligible. According to our data, soil was a permanent CH₄ sink independent of the soil water content (in the range between 6-26% WFPS - water-filled pore space) and of soil temperature (in the range of 7-28°C), supporting the concept that seasonally dry ecosystems (Mediterranean) may represent a significant sink of atmospheric CH₄. The study provides evidence that the 26% decrease or 10% increase in the ambient rainfall from annual precipitation of ca 500 mm did not significantly affect soil functionality and had a limited impact on soil-atmosphere net GHGs exchange in evergreen oak woodlands in southern Portugal.

Rhinanthus minor (yellow-rattle) can be used for restoration of species-rich grasslands but is vulnerable to competitive exclusion from high total aboveground biomass production of vascular plants. We asked (1) whether there is a threshold limit for total annual aboveground biomass production of vascular plants above which R. minor cannot establish viable population in grasslands and (2) how is cover of R. minor in grassland related to standing biomass of bryophytes. Data were collected in the Rengen Grassland Experiment (RGE) established in Germany in 1941 with following fertilizer treatments: unfertilized control, application of Ca, CaN, CaNP, CaNPKCl and CaNPK₂SO₄. Cover of R. minor and total annual aboveground biomass production of vascular plants were determined from 2005 to 2009. Further relationship between standing biomass of bryophytes and cover of R. minor was analyzed in 2006. Mean cover of R. minor over five years ranged from 0.7% to 12.3% in CaNPK₂SO₄ and control treatments, respectively. Cover of R. minor was significantly negatively related to total annual aboveground biomass production of vascular plants and cover of R. minor was below 3% in all plots with total annual aboveground dry matter biomass production of vascular plants higher than 5 t/ha. Although cover of R. minor was markedly reduced in highly productive plots in the RGE, high standing biomass of bryophytes (1.8 t/ha) in low productive control was not an obstacle for establishment of its viable population. We concluded, that viable population of R. minor can be established in grasslands only if total annual aboveground dry matter biomass production of vascular plants is below 5 t/ha regardless on standing biomass of bryophytes.

To investigate the effect of low soil pH caused by fertilization on soil available zinc in calcareous soil, this study was conducted based on a long-term experiment consisting of: (a) no fertilization (CT); (b) mineral fertilizer application coupled with 7500 kg/ha of wheat straw (WS-NPK); (c) mineral fertilizer application coupled with 3750 kg/ha of wheat straw (1/2WS-NPK); (d) mineral fertilizer application alone (NPK). Long-term fertilization results in a significant increase in soil DTPA-extractable zinc. However, the increased soil DTPA-extractable zinc is unavailable to crops and mainly confined to 0.25 mm > and 0.25 mm to 1 mm aggregates. Compared to CT, soil DTPA-extractable zinc under fertilization is more than 9.67% and 122.36% higher in 0.25 mm > and 0.25 mm to 1 mm aggregates, respectively. Furthermore, plant-available zinc in the 0-15 cm soil layer and wheat grain zinc are both significantly positive related to soil DTPA-extractable zinc in > 2 mm aggregates. Therefore, plant-available zinc in the 0-15 cm layer is closely associated with DTPA-extractable zinc in > 2 mm aggregates, and the low soil pH caused by long-term fertilization could not enhance plant-available zinc in the surface soil layer nor elevate wheat grain zinc concentration because of the occlusive effect of soil aggregates.