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Soil salinity and semi-arid and arid climate of Pakistan is a major constraint in agriculture and predominantly in foodstuff production. It limits crop yield and use of land previously uncultivated. Wheat is moderately salt tolerant. A great variation was observed between and within the cultivars (genotypes: S-24 salt tolerant and DN-27 salt sensitive) in relationship to the choice of salinity level (control and treatments: in increment of 25 mol/m³ NaCl/day to a final level of 80 and 160 mol/m³ NaCl into the nutrient solution) that will be used for screening purpose. Relative water content (RWC), membrane stability index and the activities of some antioxidant enzymes were determined after 20 and 40 days of salt stress exposure. As a result of activity enzymes, superoxide dismutase (SOD), peroxidase (POD) and catalase increased in S-24 with the increase of salt stress, while in DN-27 all the enzymes showed constant activity at all the stress levels. Meanwhile, relative water content and membrane stability index decrease the value as well as they increases the stress levels. It can be concluded that all three antioxidant enzymes were limiting factors for these genotypes and these reasons also led to the salt sensitivity in DN-27. Different selection methods should be applied to improve different traits in different conditions in wheat.

The long-term effect of 87.3 kg/ha P on the yield elements and nutrient content of maize was studied at the National Long-Term Fertilization Experiment of the Karcag Research Institute in Hungary. The soil of the experiment site is non-calcareous Luvic Phaeosem, and its soluble phosphorus (P) and zinc (Zn) content in 0-20 cm soil layer are: ammonium lactate P: 141.1 mg/kg and diethylene triamine pentaacetic acid (DTPA)Zn: 0.85 mg/kg, respectively. The effect of foliar Zn fertilization was studied at three levels of nitrogen (150, 200 and 250 kg/ha) and under 87.3 kg/ha P and 82.6 kg/ha K application in four replications. The applied Zn amount was 700 g/ha. We measured the grain yield and the thousand-kernel weight. Leaf and grain samples were analyzed for phosphorus, zinc, potassium, calcium, magnesium and manganese content. Foliar Zn application did not increase the yield significantly, but it enhanced the thousand-kernel weight. The element content did not change significantly - neither in leaves nor in kernels. Under the examined habitat circumstances even the long-term application of 87.3 kg/ha P dosage did not cause Zn deficiency to such an extent which would lead to significant yield depression of maize.

Soil microbial properties are varied by growing different crops, ultimately reflecting the growth and reproduction of crops. In this study, two types of oilseed rape (Brassica napus L. ZS11 and ZY821) and wheat (Triticum aestivum L. ZM9023) were planted in the Jianghan plain of China. Rhizosphere soil samples were collected three months after sowing. Soil physicochemical properties, enzyme activities and microbial diversity were determined. The results showed that soil available phosphorus significantly increased from 25.57 mg/kg (ZM9023) to 33.20 mg/kg (ZS11) and 35.72 mg/kg (ZY821), respectively. Invertase activity of ZS821 (0.86 mg glucose/g) was significantly lower than in ZS11 (1.04 mg glucose/g). Acid phosphatase activity under planting rapes was significantly higher than that under wheat. Urease activities significantly increased from 40.88 mg NH₄⁺-N/g soil/24 h (NFP) to 49.04 mg NH₄⁺-N/g soil/24 h (FNP) and 51.28 mg NH₄⁺-N/g soil/24 h (ZM9023), 51.60 mg NH₄⁺-N/g soil/24 h (ZY821) and 52.28 mg NH₄⁺-N/g soil/24 h (ZS11), respectively. The ACE (abundance based coverage estimator) and Chao1 indexes of bacteria of ZS11 were lower than ZY821, which were similar to ZM9023. Fertilization increased soil bacterial ACE and Chao1 indexes. However, ACE and Chao1, Shannon and Simpson indexes of soil fungi for ZS11 were significantly higher than in ZY821, which were similar to ZM9023 (except for the Shannon index).

In Hawaii, past use of arsenical pesticides has left elevated levels of arsenic (As) in some soils. Sorption isotherms of an Andosol and an Acrisol showed that the former required 1100 mg/kg, and the latter 300 mg/kg of added As to maintain 0.20 mg As/L in solution, the maximum allowable As level in streams/rivers in Hawaii. Greenhouse experiments were conducted on an Andosol (315 mg/kg total As), which was amended with 0, 5 g/kg compost, 5 g Fe/kg as amorphous Fe(OH)₃, or 250 mg P/kg as Ca(H₂PO₄)₂, and on a low-As (15 mg/kg) Acrisol, which was spiked with 0, 150 or 300 mg As/kg as Na₂HAsO₄.7 H₂O. Brake fern (Pteris vittata L.) was used as the test plant. Arsenic concentration in the fern fronds averaged 355 mg/kg in the Andosol, and 2610 and 1270 mg/kg (from consecutive plantings, 2 and 12 months after As addition, respectively) in the Acrisol spiked with 300 mg/kg of As. Chemical reactions, as suggested by sequential extractions, likely controlled the availability and uptake of soil As. Mehlich-3 extraction could be used to identify As-contaminated soils and potential phytoremediation as it correlated well with bioaccessible As and with As in fern fronds.

Soil carbon transformation was observed in long-term stationary field experiments (longer than 20 years) at two sites with different soil-climatic conditions (Luvisol, Chernozem). The following crops were rotated within the trial: row crops (potatoes or maize)-winter wheat-spring barley. All three crops were grown each year. Four different fertilization treatments were used: (a) no fertilizer (control); (b) sewage sludge (9.383 t dry matter/ha/3 years); (c) farmyard manure (15.818 t dry matter/ha/3 years); (d) mineral NPK fertilization (330 kg N, 90 kg P, 300 kg K/ha/3 years). At the Luvisol site, the control treatment showed a tendency to decrease organic carbon (C_org) in topsoil. At organic fertilization treatments the content of C_org increased: sewage sludge - +15.0% (Luvisol) and +21.8% (Chernozem), farmyard manure - +19.0% (Luvisol) and +15.9% (Chernozem). At the NPK fertilization, the increase was +4.8% (Luvisol) and +4.7% (Chernozem). The increased C_org content was also associated with an increase of microbial biomass carbon (C_mic) and extractable organic carbon (0.01 mol/L CaCl₂ and hot water extraction). The ratio of C_mic in C_org was within the range 0.93-1.37%.

This study was aimed to determine the impact of risk element content on the prevalence of the selected microbial groups in industrial soils of one of the steelworks in Poland. The concentration of heavy metals: Cd, Cr, Cu, Hg, Fe, Ni, Pb and Zn along with soil pH and the number of mesophilic bacteria, fungi, actinomycetes and Azotobacter was assessed in 20 soil samples. The limit concentrations of Cd, Pb and Zn were exceeded in five sites. However, even in these strongly contaminates sites, the studied microorganisms were abundant. The correlation between the concentration of heavy metals and microbial numbers was very weak and statistically insignificant. High numbers of fungi were observed in the contaminated sites, which was particularly interesting in one of the sites, strongly contaminated with Cd, Pb and Zn.

Arbuscular mycorrhizal (AM) root colonization is known to have beneficial effects on plant growth especially under phosphorus (P) deficit conditions. The objectives of present study were: (i) to quantify changes in early wheat root development of AM-inoculated (AMI) and AM-free (AMF) roots under limited P availability; (ii) to assess possible mitigating effect of AM inoculation on photochemical efficiency under P deficit stress. AMI (inoculated with Rhizophagus irregularis) and AMF wheat plants were grown for 20 days in low (1 μmol/L) and high (50 μmol/L)P treatments. AM inoculation affected root morphology and shoot P concentration in low P treatment. AM inoculation alleviated reduction of the total root length in low P treatment, mainly due to an increase of fine roots length(< 0.5 mm). Contrastingly, shoot dry weight was reduced by AM inoculation in low P treatment. P deficiency decreased photochemical efficiency of wheat plants. However, due to increased sink capacity and facilitated nutrient concentrations AM inoculation alleviates phosphorus deficit stress and increased photochemical efficiency.

The experiment included testing of rheological properties of dough as well as the baking quality of bread flour and bran obtained by grinding coloured wheat grains with purple pericarp (cultivars Rosso, Konini and PS Karkulka) and blue aleurone (cv. Scorpion). Common wheat cv. Mulan was used for comparison. Formulas containing 10, 15 and 20% of bran were prepared. The addition of bran increased the water loss during baking by an average of 1.28%, specific volume of bread decreased by 2 to 10 mL, and the ratio number decreased from 0.57 to 0.51. The dynamic oscillatory rheometry simulated processes occurring during baking. A higher content of bran increased the complex viscosity of dough. In the initial stages of heating, the increasing presence of bran promoted dough weakening. Starch gelatinization was also influenced by the content of bran.

In a three-year experiment, three types of soil conservation techniques were tested in the legumes cultivation systems. Our treatment types were no-till, standard tillage to the depth of 8 cm and deep tillage to 20 cm. The study evaluated winter pea (cv. Enduro), spring pea (cv. Eso), white lupine (cv. Amiga), narrow-leaved lupine (cv. Boregine) and soybean (cv. Merlin) in two autumn terms (winter pea only) and in spring term (all legume species). In no-till technology, the average yield of all legumes was 2.24 t/ha. For standard tillage (2.58 t/ha) and deep tillage (2.62 t/ha), yields were significantly higher than in no-till technology. From the monitored parameters, deep tillage appeared as the best soil treatment. Although the yield was similar to standard tillage, the soil was less stiffened, resulting in a higher content of nitrogen in the seed and a better use of the pre-crop value of the legumes. In the experiment, winter pea spring sowing term (2.93 t/ha) was better than both autumn sowings (2.68 t/ha and 2.65 t/ha).

Three-year strict experiments with winter rapeseed were conducted in three experimental stations. In the research, winter rape fertilization with elemental sulphur (S) in the doses: 20, 40 and 60 kg S/ha, boron (B) - in the dose of 2 kg B/ha and copper (Cu) - 5 kg Cu/ha were applied. Microelements were introduced separately, in treatments B and Cu, as well as in combination B + Cu. The experimental soils featured low content of sulphate sulphur SO₄^2--S and boron, medium and low copper content. Rapeseed fertilization with sulphur, boron and copper resulted in their increased concentration in plants. Sulphur at 40 and 60 kg S/ha doses affected the increase in oilseed rape grain yield by 11-12% compared to the not fertilized treatment. The dose of 20 kg S/ha did not show any significant influence on yield. The yield increased by more than 10% in the comparison to the treatment without B and Cu, was obtained due to boron, as well as combination of boron and copper fertilization. A significant increase in fat content, in relation to not fertilized treatment, ranking from 1.0-1.4% dry matter, was recorded after fertilization with the highest sulphur dose - 60 kg S/ha, as well as after application of boron and copper fertilization.

Biochar has been studied extensively in terms of its influence on soil hydrophysical properties, but only small part of results was obtained from the field experiments. In this study, the soil water content was measured in 5-10 cm depth at experimental plots which received 20 t/ha and 0 t/ha (control) of biochar amendment at the Malanta area (Slovakia). The experimental area was cultivated with maize in 2015 and spring wheat in 2016. Our field measurements show that the positive effect of biochar amendment (20 t/ha) on soil water content is strongly related to the type of the crop grown and not straightforward. Unexpectedly, during the monitoring campaign in 2015 the soil water content of the biochar-amended soil was lower than control. In 2016, negligible differences were observed in soil water contents at both experimental plots, especially during the dry spells. However, higher soil water content was measured at the plot with biochar amendment after the series of precipitation events during the physiological maturity of the spring wheat. Moreover, the biochar amendment did not increase the biomass production and yields of maize in 2015, but it significantly increased the biomass production and yields of spring wheat in 2016.

The effect of foliar application of selenium (Se) fertilizers (sodium selenite and selenate) in two different Se doses (10 and 20 g/ha) on grain yield, Se content and mechanical and technological parameters of winter wheat grain was investigated in the field fertilization experiment. Foliar spray application of Se was applied at the growth stage of the 2^nd node on the main stem (32 BBCH). Selenate foliar applications in dose 10 g Se per ha showed a significant increase of grain yield in comparison to control treatment without Se application. The mechanical and technological parameters of wheat grain were not significantly affected by both selenite and selenate foliar application. The average Se concentration was significantly lower in 2007/2008 (grain yield 8.72 t/ha) than 2006/2007 (yield 6.35 t/ha) growing season (0.133 versus 0.189 mg Se/kg dry matter). The grain Se absorption efficiency at foliar application of 10 and 20 g Se/ha of selenite and selenate were 1.35-1.45% and 13.24-15.14%, respectively.

Influence of plant growth regulators chlormequat chloride, chlormequat chloride + ethephon, ethephon, and mepiquat chloride + prohexadione-Ca + pyraclostrobin + ammonium sulphate (BAS67800F + BAS00800D) on decreasing sunflower height was evaluated. It was determined that sunflower height can be reduced by as much as 30 cm. In the case of BAS67800F + ammonium sulphate, there was a slight difference between application at BBCH 31-33 and BBCH 50-51, whereas for ethephon better application time was at BBCH 50-51. For chlormequat chloride, application at BBCH 31-33 was better, but height reduction did not endure until harvest. Flower head diameter shortly before harvest was not affected at any tested regulator. Flowering was delayed primarily at applications at BBCH 50-51.

The present studies aim at determining the antagonistic effect of selected fungi species occurring in the soil under carrot cultivation towards Altenaria dauci (J.G. Kühn) J.W. Groves & Skolko, Alternaria radicina Meier, Drechsler & E.D. Eddy, Fusarium oxysporum E.F. Sm & Swingle, Rhizoctonia solani J.G. Kühn and Sclerotinia sclerotiorum (Lib.) de Bary. The field experiment considered cover crops (oats, tansy phacelia and vetch). The control consisted of traditional carrot cultivation (without cover crops). Statistically, the smallest population of fungi was found in 1 g of soil dry weight after the application of oats, and a slightly bigger - after tansy phacelia and vetch. The largest population of fungi was obtained in the traditional cultivation of carrot. Cover crops contributed to the increase of the population of antagonistic Clonostachys spp., Myrothecium spp., Penicillium spp. and Trichoderma spp. in the soil. Regardless of the experimental treatment, those antagonistic fungi were the most effective in limiting the growth of S. sclerotiorum, A. dauci and A. radicina. The effect of those fungi was a little smaller towards F. oxysporum and R. solani. Oats as a cover crop had the best effect on the antagonistic activity of the studied fungi occurring in the soil environment of carrot.

In four-year experiments, hop was treated with 7 biologically active substances in two terms during vegetation: Lignohumate max (a mixture of humic acids and fulvic acids), Lexin (a mixture of humic acids and fulvic acids enriched with auxins), Lexenzym (a mixture of humic acids and fulvic acids enriched with auxins, phytohormones and enzymes precursors), Ascophyllum nodosum seaweed extract, synthetic auxin, humic acids and fulvic acids alone. The chlorophyll content was monitored after the application both in the vine leaves and in the branch leaves. After harvesting of the hops from the individual treatments, the yield of dry hops was determined and the cones were analysed for the content of alpha bitter acids. The results show that the most effective hop treatment was the application of Lexin and Lexenzym. The Lexenzym treatment provided a yield of dry hops of 1.86 t/ha, i.e. 0.47 t/ha higher compared with untreated control. The Lexin treatment provided yield higher by 0.41 t/ha of dry hops compared with the untreated control, while the harvested cones contained the most alpha-bitter acids (4.57%).

The decline of soil organic carbon (SOC) has aggravated salinity-related problems in semi-arid irrigation areas of the Awash river basin, Ethiopia. This study aimed at evaluating the performance of potential remediation crops on saline soil and their effectiveness for remediating soil salinity and improving pH, SOC, bulk density (BD) and hydraulic conductivity (HyCo). Rhodes grass (RHG), alfalfa (ALF), sudangrass (SUG) and blue panicgrass (Retz) (BPG) were grown in saline (3-13.9 dS/m) field plots. The crop biomass was incorporated into the soil immediately before flowering. The results show that at high soil salinity levels, BPG and SUG grew well, with the harvesting frequency of BPG being much higher than for SUG. Conversely, the growth of ALF and RHG was strongly inhibited by high soil salinity. Significant (P < 0.05) reduction of soil salinity levels (-3.2 dS/m) and related ionic concentrations, an increase of SOC (0.8% to 1.6%) and improvement of BD and HyCo were observed in BPG plots. The fast-growing nature of BPG in the hot climate of the experimental area resulted in harvests every three weeks and promoted the incorporation of high amounts of biomass to the soil and efficient soil salinity remediation. At moderately saline conditions, ALF also showed a great potential for salinity reclamation (-1.8 dS/m) and SOC accumulation. The cultivation of fast-growing annual crops proved an efficient and low-cost strategy for soil salinity mitigation and the reclamation of salinity-associated soil degradation in irrigation agriculture in Ethiopia.

Soils of forest ecosystems can release or consume methane (CH₄) depending on their specific hydrological regime. Our study reported the consumption of CH₄ by soil in a lowland broadleaf mixed temperate forest in the Czech Republic (Central Europe). The motivation of our study was to determine the importance of CH₄ fluxes in context of carbon dioxide (CO₂) fluxes of a broadleaf mixed forest. CH₄ and CO₂ emissions from the soil were measured during the 2016 vegetation season on a long transect applying the chamber technique. The average daily consumption of atmospheric CH₄ by the forest soil ranged from 0.83 to 1.15 mg CH₄-C/m²/day. This consumption of CH₄ during summer and autumn periods was not significantly affected by soil temperature and soil moisture. However, during spring period the consumption of CH₄ was positively significantly affected by soil temperature and moisture. Estimated amount of carbon (CH₄-C) consumed by the forest soil makes up a very small part of carbon (CO₂-C) participated in the ecosystem carbon cycle.

A five-year (2010-2015) field experiment was conducted to investigate warming impacts on organic carbon (OC), total nitrogen (TN) and total phosphorus (TP) contents and their ratios in bulk soil and soil water-stable aggregates in an alpine meadow of the Tibetan Plateau. Compared with unwarmed control, warming had no significant effects on OC, TN and TP contents and their ratios in bulk soil. The contents of OC, TN and TP associated with macroaggregates and microaggregates decreased, whereas those associated with silt + clay fractions significantly increased. The C:N and C:P ratios in macro- and microaggregates and silt + clay fractions decreased, with significant differences for C:P ratio in microaggregates and C:N and C:P ratios in silt + clay fractions. The results indicated that C, N and P were protected chemically in silt- and clay-size fractions under warming, which offset the loss of C, N and P protected physically by macro- and microaggregates. Both physically and chemically protected C decomposition proceeded relatively more rapidly or accumulated relatively more slowly than did N and P. Our results suggest that C, N and P distributions within soil aggregate size fractions influence their net changes in bulk soil under future climate change scenarios.

One of the most serious threats facing agricultural productivity in the world is unfavourable soil conditions. Several studies have shown that almost half of the world's land-mass is affected by either natural or human-induced pollution. This, therefore, poses a threat to agricultural improvement needed to tackle the problem of a continuous increase in the world population. The emergence of soil extremophiles with plant growth-promoting trait has proven to be a reliable means to quell the threat posed by some factors limiting soil potency. Adopting these organisms as bio-inoculants will easily proffer a solution to both biotic and abiotic soil stress. As such, the natural bio-fertilisers will help to improve the quality of the soil by making it healthy enough to sustain sufficient plant growth. This review gives an overview of the multifarious importance of extremophiles on plants grown under harsh soil conditions, with the multifaceted application of omics as a means to unveil these organisms and their benefits for environmentally sustainable agricultural systems and food safety.

The study focused on the effects of gap size on natural regeneration of European beech (Fagus sylvatica L.) and Norway spruce (Picea abies L.) and micro-environmental soil conditions in gaps of different sizes under temperate mixed forest in the Czech Republic. Six gaps comprising two for small (≥ 200 m²), medium (≥ 500 m²) and big (≥ 900 m²) each were selected. Ten circular 1 m² subsampling plots were established at 2 m intervals along individual North-South-East-West transects, including one at the gap centre. Regeneration was monitored in 2014 and repeatedly in 2019. Soil conditions were only measured in 2019. Gap size was found to be a significant parameter for European beech natural regeneration in 2014. Besides, the quick occupation of European beech in gaps at natural beech zone provoked its prolific regeneration compared to Norway spruce in 2014. However, in 2019 the recent threat of weather variabilities was responsible for the general abysmal growth performance of natural regeneration. Division of gap microsites into different within-gap positions based on prevailing light or shade conditions was helpful in assessing the significant variations of soil conditions within-gap positions and among gap sizes. Soil temperature and moisture significantly influenced the regeneration of European beech and Norway spruce, respectively.

Cotton (Gossypium hirsutum L.) is a global major crop with strong tolerance to abiotic stress, but its tolerance to cadmium (Cd) stress is unclear. The objective of this study was to determine the influence of Cd stress on the seedling growth and some physiological properties of cotton. Cotton seedlings with three fully expended leaves were treated with Cd at different concentrations (0, 25, 50 and 100 μmol/L), and seedling growth, chlorophyll (Chl) content, malonaldehyde (MDA) content, photosynthetic rate, superoxide dismutase (SOD) and peroxidase (POD) activity in the main-stem leaves were measured 5 days or 10 days after stress treatment. It was found that with the increase in the Cd concentration, the SOD and POD activity of the stressed seedlings displayed an increase first and then a decrease. The MDA content increased and the Chl decreased, which finally led to a decline in plant height and leaf area. The results suggest that cotton seedlings were adapted to low-concentration Cd stress by the increased protective enzyme activity, but over 50 μmol/L of Cd concentration would exert a significantly inhibitory effect on the photosynthetic properties and protective enzyme activity of the cotton leaves. Cotton plants can be adapted to low Cd stress by increasing the activity of the protective enzymes.

The studies determined the effect of bacteria Bacillus spp. and Pseudomonas spp. isolated from the soil after carrot cultivation on pathogenic fungi Altenaria dauci, A. radicina, Fusarium oxysporum, F. solani, Rhizoctonia solani and Sclerotinia sclerotiorum. A field experiment on carrot cultivation considered different intercrop plants (rye, buckwheat, white mustard, sunflower). Rye and buckwheat were the most conducive to the growth of Bacillus spp. and Pseudomonas spp. Those bacteria were the most effective in inhibiting the growth of F. solani, F. oxysporum and R. solani. The antagonistic effect of soil-borne Bacillus spp. and Pseudomonas spp. towards the tested fungi was the largest after the application of rye and white mustard as intercrop plants in the cultivation of carrot. Buckwheat and sunflower showed a slightly smaller influence on the antagonistic activity of the studied bacteria. Bacillus ssp. had a significantly lesser antagonistic effect than Pseudomonas ssp.

The aim of this study was to test different soil phosphorus (P) extraction methods in relation to plant P uptake. A greenhouse pot experiment was conducted with spring wheat. The soils were extracted with the following methods/extractants: H₂O, CaCl₂, LiCl, iron oxide impregnated filter papers (Fe-oxide P_i), Olsen, calcium-acetate-lactate (CAL), cation and anion exchange membranes (CAEM), Mehlich 3, Bray and Kurtz II (Bray II), citrate-bicarbonate-dithionite, organic P, HCl, acid ammonium oxalate, total P. Plant P uptake was in the range of the P extracted by neutral salt solutions (CaCl₂, LiCl). P extracted with H₂O, CaCl₂ and CAEM correlated best with plant P uptake over one growing season, while several established soil P test methods, including CAL, Mehlich 3 and Bray II, did not show significant correlations. When grouping the soils according to pH, the weaker extraction methods (H₂O, CaCl₂, LiCl) showed significant correlations with plant P uptake only for the low and intermediate pH groups (pH in 1 mol/L KCl ≤ 6.6), while some of the stronger extraction methods (CAL, Mehlich 3, Bray II, dithionite, oxalate, total P) showed significant correlations only for the high pH group (> 6.6) comprised of calcareous soils. It was concluded that weaker P extraction methods, especially neutral salt solutions best predict plant-available P in the short term. However, they do not perform well for calcareous (and clayey) soils and do not account for P that may become available beyond one growing season.

Application of composted pig manure (PM) is a traditional practice to improve soil fertility, whereas generally leads to some environmental questions. The effects of PM application on Cd, Cu and Zn accumulation in soil and maize were investigated based on a long-term field trial in Northeast China, including control (CK), PM_L, PM_M, and PM_H, receiving 0, 100, 250 and 500 kg total N/ha/year from 2002 to 2008 and 0, 10, 25 and 50 t fresh weight/ha/year from 2009 to 2018, respectively. Results showed that long-term soil application of PM increased maize grain yield, soil organic carbon (SOC) contents, coupled with significant accumulation and availability of Cd, Cu, and Zn in soil (0-15 cm). Compared with CK, the soil total Cd, Cu and Zn concentrations significantly increased by 105, 287 and 108% at high PM rate, respectively. Notably, the increments enhanced these heavy metals storage in maize roots rather than in grains. Moreover, the application of PM confirmed vertical transport of heavy metals in the tested soil, particularly for Cd and Cu in PM_H treatment. Overall, the repeated application of PM can cause the accumulation and leaching of Cd, Cu and Zn in soil.

The objective of the study was to examine a possibility of predicting phosphorus leaching from the top layer of agricultural soils by rainfall simulations by means of three multi-nutrient soil tests: Mehlich 3, NH₄-acetate extraction and water extraction (1:5, w/v). Another objective was to determine parameters of maximum phosphorus losses after an extreme load of rainfall on the top layer. Forty soils from different localities of the Czech Republic were used for the experiment. A leaching experiment was conducted in pedological cylinders with a soil layer of about 1 cm and with the bottom from a glass microfibre filter with pores 1.2 μm in size. Within 15 days the soils were flooded ten times with 25 mm of simulated rainfall in a minimum interval of 1 day. The closest regression between the soil test and phosphorus leaching was computed for NH₄-acetate soil test (R² = 0.8831) and Mehlich 3 test (R² = 0.8572) after the first application of 25 mm of rainfall. In water extraction it was for the mean of 10 simulated rainfalls (R² = 0.8674). As leaching proceeded, the closeness of regression diminished due to fluctuations of P concentration in leachates (increases and decreases), mainly in soils with higher P-test. The increase in P concentration could be caused by the activation of phosphorus from Fe-phosphates under anaerobic conditions in wet soils. The steepest decrease in P concentration in leachates was observed in light soils with low CEC value and higher initial P-test.

Mehlich 3 is an extractant used worldwide for extracting bioavailable nutrients in soils; however, its extraction abilities for sulfur (S) are still not well described. The aim of this preliminary study was to compare the results of Mehlich 3 determined soil S fraction (S_M3) with the results of sulfur fractionation, mainly focusing on bioavailable S (S_av - sum of water-extractable (S_w) and adsorbed (S_ads) sulfur). Air dried soil samples from commonly used agricultural soils were chosen for the analyses. The following S fractions were determined: (i) S_w; (ii) S_ads; (iii) S_av; (iv) 1 mol/L HCl extractable (S_HCl); (v) estersulfate (S_es); (vi) organic (S_org) and (vii) total (S_tot). The median value of S_M3 (18.3 mg/kg) was similar to S_av (17.9 mg/kg). From the correlation and regression analysis it is clear that S_M3 results are in close relationship with S_av form. On the other hand, the relationships between S_M3 and organic S (including S_HCl) were very weak. Based on the obtained results it can be concluded that Mehlich 3 method has a good potential to determine bioavailable sulfur in commonly used agricultural soils. However, especially the plant response should be further studied to confirm this theory.

The present study investigated the impact of transgenic Bacillus thuringiensis (Bt) cotton on several aspects of arbuscular mycorrhizal (AM) fungus Funneliformis mosseae. The results showed that Bt cotton significantly inhibited spore germination and pre-symbiotic hyphal growth. The appressorium density, arbuscule frequency and colonization intensity in Bt roots were also decreased. The statistical analysis demonstrated that the transformation event resulted in the inhibition of hyphal development and colonization. The reduced interaction between AM fungi and plants could affect nutrient uptake and transportation in plant-fungus symbiosis. The mechanism might involve the direct toxicity of Bt toxins or the interference of signal perception between AM fungus and Bt cotton.

Monitoring of grassland dry matter yield (DMY) is important for the economy and ecosystem management, but it is a time-consuming process. Calculating the correlation between compressed height (CH) and DMY is a faster way to estimate DMY. The aim of our study was to use CH in order to predict DMY for a meadow with different fertilization management and plant species composition. Four fertilization treatments and one unfertilized control were established in a mesophilic meadow in the Czech Republic. Using a rising plate meter (RPM), CH was measured before the first and second cuts. In addition, the cover of individual vascular plant species was estimated. Significant correlations between CH and DMY were ranging from 0.41 to 0.79 for treatments without nitrogen fertilization in the first and second cuts; for treatments with nitrogen fertilization there was a significant correlation only in the second cut. According to our results, the RPM method seems to be suitable for a rough DMY estimate for meadows with coverage of about 60% grasses, 10% legumes and 30% forbs. However, considerable changes in the cover of tall forbs (e.g. Urtica dioica L.) or tall grasses (e.g. Dactylis glomerata L.) could be the main sources of DMY estimation inaccuracy.

Spectral data contain information on soil organic and mineral composition, which can be useful for soil quality monitoring. The objective of research was to evaluate hyperspectral visible and near infrared reflectance (VNIR) spectroscopy for field-scale prediction of soil properties and assessment of factors affecting soil spectra. Two hundred soil samples taken from the experiment field (soil depth: 30 cm; sampling grid: 15 × 15 m) were scanned using portable spectroradiometer (350-1050 nm) to identify spectral differences of soil treated with ten different rates of mineral nitrogen (N) fertilizer (0-300 kg N/ha). Principal component analysis revealed distinction between higher- and lower-N level treatments conditioned by differences in soil pH, texture and soil organic matter (SOM) composition. Partial least square regression resulted in very strong correlation and low root mean square error (RMSE) between predicted and measured values for the calibration (C) and validation (V) dataset, respectively (SOM, %: R_C² = 0.75 and R_V² = 0.74; RMSE_C = 0.334 and RMSE_V = 0.346; soil pH: R_C² = 0.78 and R_V² = 0.62; RMSE_C = 0.448 and RMSE_V = 0.591). Results indicated that hyperspectral VNIR spectroscopy is an efficient method for measurement of soil functional attributes within precision farming framework.

In this experiment we proved an effect of dolomite limestone on chemical immobilization in soil contaminated by trace metals, namely Cd, Pb, and Zn. Primary, we set up lysimeter pot experiment to measure soil leaching without vegetation. Willow clone (S. × smithiana Willd) was cultivated in the second lysimeter pot as a new approach to monitor Pb, Cd and Zn leaching, which was affected by soil liming (used in 1% rate). At the time of both harvests, aboveground biomass increased significantly at the amended variant. After the second harvest aboveground biomass production increased by 80% in comparison with the first one, Cd and Zn concentration in biomass decreased 2-fold and 3-fold, respectively. Dolomite limestone as a process of liming: (i) restricted metals leaching from the soil substrate; (ii) reduced metal uptake by willow; and (iii) increased biomass production of willow. Liming also alleviated the plant stress imposed by risk elements resulting in better plant growth and lower levels of stress markers (total nitrogen content and the main amino acid metabolism parameters in the willow leaves) yet through different mechanisms.