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Sunflower plants were grown on soil contaminated with several levels of Cd (from 0.3 to 15 mg Cd kg/soil). Cd and nutrient (Cu, Zn, Fe, Ca, K, Mg) contents were evaluated in root and aboveground biomass during the vegetative growth period (from the emergence of the cotyledon leaves to the flower bud phase). An overall increase of Cd content was found in the plants during the growing cycle. Significant interactions were found between Cd contamination levels and phenological stages for Cu, Fe, Ca and Mg content in the whole plant. Cd levels involved significant increases of such nutrients only at the flower bud phase. At this stage, significant interactions between Cd levels in soil and plant portions (root and shoot) were found only for micronutrients (Zn, Cu, Fe). The translocation of micronutrients from root to the shoot was negatively affected by Cd, which probably interferes with the mechanisms of the element transport in the plant. Root stored about 70% of the total Cd and showed greater imbalance in nutrient content compared to the aboveground portion. Cadmium affects plant nutritive status in a different way depending on Cd contamination level, nutrient considered, plant portion and phenological stage.

Minituber production by traditional method is an expensive procedure due to limited productivity. In order to increase the multiplication rate of seed material in vitro, multiple techniques have been assayed in the last decades. The aeroponic system is a soilless culture system, where roots are kept in a dark environment saturated with aerosol of nutrient solution. Aeroponics technology is potentially efficient for specific potato cultivars. The aim of this study was to investigate the multiplication rate of microtubers of national cultivars in aeroponics while maintaining weekly intervals between harvests. The total number of harvests was 14 to 15 depending on year. The results of the experiments were analysed with ANOVA and means were separated with the Tukey's test at 5% P-value. The most important parameter of minituber production, their number, was on average 32.5-36.0 per plant and 1268-1396 per m² depending on cultivar. Number of minitubers was two to three times greater in the case of aeroponic production than by traditional method. A full economic analysis is necessary to prove that this production technique can be put into practice.

Soil organic matter (SOM) is a major index of soil quality assessment because it is one of the key soil properties controlling nutrient budgets in agricultural production systems. The aim of the in situ near-infrared spectroscopy (NIRS) for SOM prediction in paddy area is evaluation of the potential of SOM and prediction of other soil properties. There are keys for soil fertility and soil quality assessments. A spectral reflectance of 130 soil samples was collected by field spectroradiometer in a region of near-infrared. Spectral reflectance collections were processed by the first derivative transformation with the Savitsky-Golay algorithms. Partial least square regression method was used to develop a calibration model between soil properties and spectral reflectance, which was used for prediction and validation processes. Finally, the results of this study demonstrate that NIRS is an effective method that can be used to predict SOM (R² = 0.73, RPD (ratio of performance to deviation) = 1.82) and total nitrogen (R² = 0.72, RPD = 1.78). Therefore, NIRS is a potential tool for soil properties predictions. The use of these techniques will facilitate the implementation of soil management with a decreasing cost and time of soil study in a large scale. However, further works are necessary to develop more accurate soil properties prediction and to apply this method to other areas.

This research was conducted to assess the influence of long-term tillage system on soil organic carbon, microbial biomass carbon, root biomass and crop yield in spring wheat-field pea rotation fields in a rainfed semi-arid environment from 2013 through 2015. The treatments were; conventional tillage with stubble removed (T); no-till with stubble removed (NT); no-till with stubble retained (NTS) and conventional tillage with stubble incorporated (TS) arranged in a randomised complete block design with three replicates. The soil organic carbon in NTS increased by 16% and 14% over T and NT. Compared with the T and NT, NTS increased soil microbial biomass carbon by 42% and 38% in 0-30 cm depth, respectively. Root biomass was significantly increased in NTS by 47% and 54% over T and NT, respectively. Across the three years, NTS had an average grain yield of 53% and 41% higher than T and NT, respectively. Compared with NTS, T and NT decreased root biomass by 54% and 48%, respectively. In view of the limited and erratic biomass production in this region, integration of no-till with straw mulching is recommended for soil fertility improvement, environmental quality and sustainable crop production.

The study evaluates the effect of liming materials application in combination with NPK fertilizer and borax on macronutrient contents (nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg)), in an extremely acid soil and raspberry leaves and fruits during a two-year period. Liming increased soil pH, N mineral content, P, Ca and Mg soil content, while K content either increased (dolomite and borax application), or decreased (lime application). The N and P contents in raspberry leaves after liming increased significantly, but P content remained below the optimal values. Some treatments with lime caused a decrease in K content in leaves, while dolomite and borax application increased K content. Initially optimal Ca content in leaves increased significantly in the treatments with lime, but decreased after dolomite application. The Mg content in leaves increased after dolomite and borax application, but mainly remained below optimal values. Liming either did not alter or only slightly altered macronutrient contents in raspberry fruits.

The aim of this study was to determine whether meat and bone meal (MBM) can be used as NP fertilizer for spring barley grown for fodder. A two-factorial field experiment was conducted in Poland. Experimental factor I was MBM dose (0, 1.0, 1.5, 2.0, 2.5 t/ha/year) which was compared to the mineral fertilization (NPK), factor II was the year of the study (two consecutive years). MBM used in doses higher than 1.0 t/ha had a more beneficial influence on the grain yield of spring barley and grain plumpness than mineral fertilizers. The positive yield-forming effect of MBM doses 2.0 t/ha and 2.5 t/ha was statistically significant. The nitrogen (N) content of grain was similar in treatments with MBM and mineral fertilization. The two highest MBM doses contributed to a significant decrease in the phosphorus (P) content of grain, particularly in the second year of the study, in comparison with the remaining MBM doses and mineral fertilizers. Grain yield and N content were also affected by the year of the study, due to weather conditions and the residual effect of MBM. The optimal MBM dose was 1.5 t/ha, which allowed to produce 5.1 t/ha of the plumpest grain whose N and P content was consistent with the feeding standards for livestock.

Two-way field experiment was carried out in a split-plot design in 4 growing seasons at the Experimental Station of the Bydgoszcz University of Science and Technology in Mochełek (Poland). The forecrops for winter triticale cv. Tulus were lupins: yellow, blue and white, field pea and spring barley. Nitrogen (N) fertilization in triticale after harvesting forecrops was: 0-60-120-180 kg N per ha. Average long-term yields of grain and protein in triticale after leguminous forecrops were statistically similar, by 0.84 t/ha and 86 kg/ha higher than after spring barley. On plots without mineral N fertilization, by over 1.5 t/ha more grain was obtained after leguminous forecrops, and by 142 kg/ha more protein than on the plot after spring barley. However, the rate of 180 kg N/ha guaranteed obtaining a significantly highest mean protein yield in triticale. The applied mineral N fertilization at rates from 60 to 180 kg N/ha did not significantly vary the average yield of winter triticale. Mineral nitrogen (N_min) content in the layer 0-60 cm after harvesting the leguminous forecrop without mineral N fertilization was by 25.5% higher than after harvesting spring barley fertilized with a rate of 60 kg N per ha.

This study investigated copper (Cu) and lead (Pb) enrichment factor (EF) and mobility factor (MF) as possible indicators of their uptake by spinach (Spinaceae oleraceae) and carrots (Daucus carota) grown on a sludge-amended luvisol (SAL). Sewage sludge was applied to luvisol at different rates and spinach and carrots planted. Enrichment of Cu and Pb in SAL was determined, and values regressed with those of Cu and Pb concentrations in spinach and carrots. Concentration of Cu and Pb in vegetables was calculated using the regression model obtained, and calculated values compared with actual values. Pb MF were higher than Cu MF but Cu and Pb EFsoil values were < 3.0, indicating minor enrichment from sludge addition. EF had 10% reliability in predicting Cu and Pb uptake in vegetables. MF was more than 70% reliable in predicting carrot Cu uptake and spinach Pb uptake. EF and MF are not effective as predictors of heavy metal uptake by vegetables. The role of other soil components including root exudates and by-products from microbial activities should also be investigated.

Among Meliaceae derivatives, neem cake is usually used as a fertilizer; however its origin and industrial processing are often unknown, so that its effect on soil fertility is not predictable. In this study, the effect of soil incorporation of 6 commercial neem cakes and leaves of Melia azedarach L. on nitrogen (N) and carbon (C) dynamics was investigated in a 118-day laboratory incubation experiment. Neem cake at a rate of 8 g/kg of soil and melia leaves at 16 g/kg were incorporated into the soil and their net N and C mineralisation were evaluated 2 h after application and at day 1, 2, 6, 12, 26, 54 and 118, by analysing a 50-g soil sample placed in 250 glass jars. The apparent net N mineralisation was well predicted by N concentration and C/N ratio of derivatives. The derivatives with a C/N ratio < 24 caused a net N mineralisation, whereas those with a C/N ratio ≥ 24 caused net N immobilisation. C mineralisation ranged between 15% and 25% and was not related to chemical composition of the derivative. Neem cake with a C/N ratio < 24 can be used to add N, while neem cake with a C/N ratio > 24 can be used to reduce soil mineral N.

Soil testing in the Czech Republic is based on the use of the Mehlich 3 method for determination of macronutrients and diethylentriaminepentaacetic acid (DTPA) and hot-water extraction for determination of micronutrients. Since inductively coupled plasma optical emission spectrometers have become commonly used in soil testing laboratories, Mehlich 3 extractant could be used very effectively also for a simultaneous micronutrient determination. To take full advantage of the universal Mehlich 3 extractant, new criteria for evaluation of the content of micronutrients in this extractant are needed. The criteria presented in this study were obtained by a simple calculation of criteria from the relationships between the Mehlich 3 extractant and the extraction methods for which the criteria were available (DTPA for copper, zinc, manganese, iron and hot-water extraction for boron). The first calculated estimates of the criteria were pre-validated and slightly adjusted to minimize the difference between the frequency of the samples in each category after determination and evaluation by the compared methods. Further adjustment of the presented critical values with respect to the field and pot experiments will be necessary in the future.

Four clones of short rotation coppice (SRCs) were investigated for phytoextraction of soil contaminated by risk elements (REs), especially Cd, Pb and Zn. As a main experimental factor, the influence of rotation length on the removal of REs was assessed. The field experiment with two Salix clones (S1 - (Salix schwerinii × Salix viminalis) ×S. viminalis; S2 - S. × smithiana) and two Populus clones (P1 - Populus maximowiczii × Populus nigra; P2 - P. nigra) was established in April 2008 on moderately contaminated soil. For the first time, all clones were harvested in February 2012 (2012_4y) after 4 years. Subsequently each plot was equally split into halves. The first half of the SRC clones was harvested in February 2014 after 2 years (2014_2y) and again it was harvested in February 2016 after further 2 years (2016_2y). The second half was harvested in February 2016 after 4 years (2016_4y). The results showed that the biomass production for the second 4-year harvest period was significantly higher for all clones but the metal concentration was lower in the mentioned period. 4-year rotation seems to be more advantageous for the phytoextraction than two 2-year rotations. The highest metal removal presented by remediation factors (RFs) per 4 years for Cd (6.39%) and for Zn (2.55%) were found for S2 in the harvest 2016_4y treatment. Removal of Pb was the highest by P1 clone with very low RF per 4 years (0.04%). Longer rotation is also economically superior.

A three-year field experiment was conducted in North-East Poland. Each year three sulfur fertilization rates in the form of sulphate (S-SO₄^2-) and pure (S-S⁰) sulfur were applied: 40, 80, and 120 kg/ha. After the third year of the study, the application of sulfate and elemental sulfur decreased the zinc content of 0-40 and 40-80 cm soil layers, as compared with soil sampled before the experiment. Over the entire experimental period, sulfur fertilization had no significant effect on changes in the natural copper content of soil at a depth of 0-40 and 40-80 cm. Manganese concentrations remained at a similar level at a soil depth of 0-40 cm. The manganese content of the 40-80 cm soil layer was substantially lower than in the 0-40 cm horizon. An insignificant increase in the lead content of soil was observed. The applied doses of sulfate and elemental sulfur led to an increase in the cadmium content of soil depth of 0-40 cm. Sulfur fertilization contributed to a decrease in the nickel content of soil. The applied doses of sulfate and elemental sulfur exerted a stronger effect in the 0-40 cm soil layer than in the 40-80 cm horizon.

Water stress is a frequent and critical limit to wheat (Triticum aestivum L.) production in North China. It has been shown that photosynthetic active radiation (PAR) is closely related to crop production. An experiment was conducted to investigate the effects of deficit irrigation and winter wheat varieties on the PAR capture ration, PAR utilization and grain yield. Field experiments involved Jimai 20 (J; high yield variety) and Lainong 0153 (L; dryland variety) with non-irrigation and irrigated at jointing stage. The results showed that whether irrigated at jointing stage or not, there was no significant difference between J and L with respect to the amount of PAR intercepted by the winter wheat canopies. However, significant differences were observed between the varieties with respect to the amount of PAR intercepted by plants that were 60-80 cm above the ground surface. This result was mainly caused by the changes in the vertical distributions of leaf area index (LAI). As a result, the effects of the varieties and deficit irrigation on the radiation use efficiency (RUE) and grain yield of winter wheat were due to the vertical distribution of PAR in the winter wheat canopies. During the late growing season of winter wheat, irrespective of the irrigation regime, the RUE and grain yield of J were significantly (LSD, P < 0.05) higher than those of L. These results suggest that a combination of deficit irrigation and a suitable winter wheat variety should be applied in North China.

An incubation study was carried out to investigate the influence of nitrogen rates to determine optimum C/N ratio under various moisture levels for straw decomposition and sequester carbon (C) in the soil. The aim was to observe straw carbon mineralization through measuring the amount of CO₂ evolution. A clay loam topsoil mixed with maize straw was supplied with four nitrogen rates (0.04, 0.08, 0.16, 0.32 g N/kg) using (NH₄)₂SO₄ to adjust C/N ratios at 82, 42, 20, and 10. Soil moisture was maintained at 55%, 70%, 85%, and 100% of field capacity incubated at 25°C for 53 days. The experiment was set up with 16 treatments arranged in complete randomized design. Results showed that mixing of straw with soil increased 50% cumulative CO₂-C compared to controls. Averagely, about 44% of added maize straw C was mineralized to CO₂-C. Straw addition along with nitrogen and moisture had significant relationships (P < 0.05) to cumulative CO₂-C, soil organic C and microbial biomass C. There was a highly significant relationship (R² = 0.99) between CO₂-C emission and incubation time.

Changes of soil organic matter (SOM) parameters were investigated in a haplic Luvisol with medium-heavy texture. Soil samples were taken from several layers at minimum (MT) and conventional (CT) tillage plots of a field experiment in Sitzenhof (Germany). All cultural practices except for tillage (crop rotation, fertilizing, protection measures, etc.) were identical over the whole time of the experiment. The concentrations of oxidizable carbon C_ox and its constituents (humic acids (HA), fulvic acids (FA), and hot-water soluble carbon) are comparable in layers 15-20 cm in both variants. In 0-15 cm and 30-55 cm layers, these concentrations were higher in the MT variant. A similar trend was observed in the colour quotient values of humic substances Q4/6, which indicates increasing condensation of humus substances (HS) at deeper layers in both variants, and it is also confirmed by a humic to fulvic acids ratio HA:FA. Concentrations of SOM fractions were higher (except 15-20 cm layers) in the MT than CT treatment throughout the profile, especially below the 30 cm depth. The SOM did not accumulate markedly in the surface layer of long-term MT treatment.

Little information is available on how fertilizer application affects concentration of many elements in peeled potato (Solanum tuberosum) tubers and peels. We analyzed how long-term application of cattle slurry and mineral N, P and K fertilizers affects the yield of tubers, their dry matter content and concentrations of elements. In 2009, potatoes tubers were collected in control, cattle slurry (CS), mineral N₄P₂K₂ and combined CSN₄P₂K₂ treatment of the Ruzyně Fertilizer and Crop Rotation Experiment established on Illimerized Luvisol in Prague (Czech Republic) in 1955. Amount of N, P and K supplied by CS was 138, 30 and 172 kg/ha and the amount supplied by N₄P₂K₂ was 110, 31 and 186 kg/ha. Yield of fresh potatoes ranged from 20.6 in the control up to 31.2 t/ha in CSN₄P₂K₂ treatment. Dry matter content of unpeeled tubers, peeled tubers and potato peels was not significantly affected by fertilizer treatments probably because of not excessive N application. Normal cropping practices with application of CS and mineral N, P and K fertilizers did not significantly increase concentrations of trace elements in peeled tubers or potato peels on neutral soil with low trace elements availability. Concentrations of many elements (N, P, K, Ca, Mg, Cd, Cr, Cu, Mn, Ni, and Zn) were higher in potato peels than in peeled tubers, but the differences in the case of trace elements were relatively small.

This paper evaluates the response on the rate of photosynthesis (P_n), transpiration (E), stomatal conductance (g_s) and water use efficiency (WUE) in 15 genotypes of young hop plants (19 BBCH) grown in greenhouses in the conditions of water deficit for the period of 9 days. On the 9^th day, the relative content of water in the experimental plants fluctuated between 70.14-75.20%. The levels of P_n and g_s evidently dropped in the monitored species as a result of the water deficit. The decrease of P_n in the experimental plants compared with the control group was largest in the Saaz Os. cl. 72 (by 77.5%), Magnum (by 73.3%) and Columbus (by 62.3%). To the contrary, the lowest P_n decrease was noted in the case of genotypes Saaz Late (by 15.7%), Vital (by 23.9%) and Premiant (by 24.2%). All genotypes except for cv. H16 showed an evident decrease of E. Judging by the highest values of WUE, the most effective water management was shown by Premiant, Vital and Saaz Late genotypes. A significant stomatal limitation of photosynthesis due to water stress was identified in the most widely used Czech cultivar, Saaz Os. cl. 72, with low values of stomatal conductance, photosynthetic rate and transpiration.

The four-year trial was conducted in north-western Slavonia (main arable crop producing region in Croatia) to evaluate the effects of different tillage systems on the water content of silty loam soil (Albic Luvisol) and yields of maize (Zea mays L.) and winter wheat (Triticum aestivum L.). The tillage systems compared were: conventional tillage; reduced conventional tillage; conservation tillage I; conservation tillage II (CM); no-tillage (NT). During the study period, there were one dry, two wet and one average season. Soil water content (SWC) was measured at 0-5, 15-20 and 30-35 cm depths on a monthly basis. Tillage systems had significant (P < 0.05) effects on SWC and yields. The highest average SWC in all seasons was measured under the NT system, followed by the CM system. In the second season, the highest yield was measured under the NT system while in all other seasons, it was under the CM system.

In conjunction with soil type and climate, the use of nitrogen fertilizers is a major factor affecting nitrous oxide emissions. This study compares injection of pig slurry and pig slurry digestate at 15 or 20 cm depths with trailing-hose application followed by immediate incorporation. The work was based on a laboratory microcosm experiment with undisturbed soil cylinders (0-30 cm depth) from three arable soils (Histosol, Gleysol and Plaggic Anthrosol). Soil cylinders were fertilized with pig slurry and pig slurry digestate (150 kg N/ha) and emissions of N₂O, CH₄ and CO₂ were monitored. The comparison of application techniques over a 37-day period show that soil type and application technique, had a strong (P < 0.001) impact on N₂O emissions. Fertilization with pig slurry showed no significantly higher N₂O emissions than pig slurry digestate. Fertilizer injection significantly increased N₂O emissions compared to fertilization with a trailing-hose with incorporation.

Studies on glomalin-related soil protein (GRSP) have focused on soil aggregation and fungal physiology, whereas it is not known how exogenous GRSP could positively impact on these processes, soil enzyme activity and plant growth. Easily extractable GRSP [EE-GRSP, 0.022 mg protein/mL citrate buffer (20 mmol, pH 7.0)] from a 26-year-old citrus orchard was exogenously applied into 5-month-old potted trifoliate orange (Poncirus trifoliata) for 3 months to evaluate effects on soil water-stable aggregate distribution, relevant soil enzyme activities and plant growth. Depending on the applied concentrations as 1/2, 1/4 or full strength, exogenous EE-GRSP generally significantly increased the distribution of soil water-stable aggregates and mean weight diameter (MWD, an aggregate stability indicator). Values of MWD and plant biomass production curvilinearly positively correlated with exogenous EE-GRSP applications. Exogenous EE-GRSP generally significantly increased the activity of rhizospheric polyphenol oxidase, peroxidase, acid and alkaline phosphatase. Both the 1/2-strength and 1/4-strength, but not the full-strength exogenous EE-GRSP, significantly stimulated plant growth performance. Our results firstly demonstrated the positive contribution of exogenous EE-GRSP to soil aggregation, relevant rhizospheric enzyme activities and/or plant growth, which has important implications for exploring GRSP in enhancing soil structure and/or plant performance.

Recent concerns over the environmental impact of peat harvesting have led to restrictions on the production of peat based potting substrates. Therefore the objective of our study was to evaluate the use of compost and biogas residues without and each with 20% additives (Perlite, Styromull, Hygromull, Lecaton, Peat, Cocofiber) as a substitute for peat. Ryegrass (Lolium perenne L.), chosen as an experimental plant, was cut four times. The results reveal that compost and biogas residues are suitable potting substrates. The incorporation of additives mixed into the basic materials partly resulted in higher yield and nutrient uptake. However, the difference among additives was mainly insignificant. Incorporation of Hygromull, especially into biogas residues favored plant growth and increased the uptake of nutrients, which is attributed to the fact that Hygromull stores nutrients and delivers them even later in the growing season. Furthermore Hygromull reduces the salt concentration of the medium, resulting in favored plant growth of younger plants.

The present study investigated the adsorption-desorption behaviour of triazophos on Indian soils at 10, 20 and 40°C using batch equilibrium technique. Results revealed that adsorption isotherms were explained better by Freundlich model and adsorption coefficient (K_f) decreased with increase in temperature indicating that adsorption was affected strongly by temperature. Moreover thermodynamic analysis showed that triazophos adsorption onto soil was spontaneous, exothermic and might have occurred through chemisorptions, hydrogen bonding or ligand-exchange interactions. Desorption results depicted that nearly 90% of the pesticide amount adsorbed by soil was retained by it at 10°C and the amount decreased with increase in temperature. Thus, the pesticide has a potential to contaminate surface and ground water at higher temperature due to weak adsorption on tested soils and release of more adsorbed pesticide during desorption with water. At temperature below 20°C, pesticide became almost immobile and therefore soil remediation may be required. The study highlights the importance of temperature in regulating the application of triazophos in soil.

The objective of this paper is to clarify the impacts of straw covering method on runoff and soil erosion in summer maize field on the Loess Plateau of China. A field experiment was conducted (2012-2014) in the artificial raining hall of the State Key Laboratory, with three soils and five straw covering methods. Three soils were Heilu soil (Calcisols), Huangmian soil (Fluvisols) and Lou soil (Anthrosols). Five straw covering methods were CK - no straw mulching and no stubble standing on the surface of the plot; T30 - 30 cm of winter wheat (WW) stubble standing above ground; M30 - 30 cm of WW stubble was harvest and mulched on the surface of the plot; M10T20 - 20 cm of WW stubble standing and 10 cm WW straw mulching on the surface of the plot; M20T10 - 10 cm of WW stubble standing and 20 cm of WW straw mulching on the surface of the plot. The results showed that (1) straw covering method not only impacted ITRP (initial time of runoff producing), but also affected runoff volume in summer maize field on the Loess Plateau of China. M10T20 was the best to postpone ITRP and to reduce runoff volume in summer maize field. (2) Different covering methods produced different sediment yield in summer maize field. M30 was the best to reduce soil erosion in summer maize field on the Loess Plateau of China. (3) When one covering method was used to reduce runoff or soil erosion, bulk density and soil mechanical composition (silt content, clay content and sand content) should be considered seriously.

The field experiment with different soil tillage treatments has been carried out in Prague-Ruzyně locality (Czech Republic) since 1995. Data of two growing cycles in the years 2007-2010 and 2011-2014 were evaluated. Tillage technique was decisive for changes in soil characteristics and crop yields. Bulk density, organic carbon (C_org) and microbial biomass C (C_mic) were more equilibrated throughout all tested soil layers (0-0.1; 0.1-0.2 and 0.2-0.3 m) in conventional tillage (CT). In reduced tillage (RT) and no-tillage (NT) treatments significant accumulation of C_org and increase of C_mic in the surface layer were found, compared to CT. No significant differences in C_org and C_mic between two growing cycles were determined; however, mostly higher values were obtained in the top layer of NT during the second growing period. Higher bulk density under conservation tillage techniques did not negatively affect soil characteristics and should be taken in consideration for data evaluation as it can alter interpretation of their changes in the soil profile. Crop yields were comparable in CT and RT. Yield decrease in NT was mostly observed for winter wheat and pea. Beneficial effects of RT and NT conserving soil moisture on crop yield were not observed in dry years.

Potato yield is affected by an interaction between nitrogen (N) and potassium (K) supply. This hypothesis was verified in a series of field experiments conducted during 2010-2013 in Albania (AL), Czech Republic (CZ) and Poland (PL). The two-factorial experiment was founded on relative scales of K (0, 50, 100, and 150%), and N application rates (75% and 100%) of the recommended doses, which were country-specific. The average tuber yield was doubled for AL, increased by 50% for PL, and by 15% for the CZ in response to K and N interaction. These differences are caused by an increase in the apparent nitrogen efficiency (ANE), which rose significantly by the progressive Krates. Maximum average ANE of 90 kg tubers/kg N was recorded in AL; it was 2-fold lower in CZ. Top average apparent potassium efficiency (AKE) of 65 kg tubers/kg K was recorded in PL; it was 4-times lower in CZ. The relationships between AKE and ANE clearly demonstrate the tight interaction between the N and K, and its effects on potato yield. However, a sound K application management should be adjusted to the local edaphic and climatic conditions.

The aim of this study was to compare the incidence of pathogens and pesticide residues in rapeseed samples depending on integrated and organic cultivation systems and cultivars. No pesticide residue was detected in seeds coming from the organic production system. However, trace amounts of pesticide residues admissible in rapeseed protection were detected for samples from integrated pest management. Seeds from both cultivation systems were most frequently infested by fungi Alternaria brassicicola and A. alternata. The greatest number of Leptosphaeria spp. cultures was obtained from seeds from organic cultivation.

This study evaluated the effects of biochar application on some properties of an alkaline soil and on lentil (Lens culinaris Medik) growth. Lentils were grown in the soil amended with the rates of 0.4, 0.8, 1.6, 2.4, and 3.3 weight percent of two biochars (B₁ and B₂), produced from rice husk under different pyrolysis conditions. Lentils were harvested after 70 days. Soil samples were also analysed for changes in physico-chemical properties. The results indicated that biochar application significantly increased soil organic carbon, cation exchange capacity, available potassium and below ground biomass of lentil, while it decreased soil bulk density. The results suggested that biochar application to alkaline soils has benefits to both soil quality and plant growth.

The aim of the studies was to determine the effect of the used herbicides and their mixtures on the level of glycoalkaloids (TGA) in the leaves and tubers of three edible potato cultivars. The studied factors were: I - three cultivars: Cekin, Satina and Tajfun. II - five ways of care: 1. mechanical care - the control object and four objects using herbicides Command 480 EC, Afalon Dispersion 450 SC and Stomp 400 SC. The content of glycoalkaloids both in the leaves and in the tubers of the edible potato significantly depended on the genotype. The highest content of TGA characterised the cv. Cekin - 623.5 mg/kg and 67.21 mg/kg of fresh weight (FW), respectively, while the smallest was found in cv. Satina - 339.3 mg/kg and 33.60 mg/kg of FW, respectively. Herbicides used in the experiment caused the increase of the content of glycoalkaloids compared to the tubers from the control object. However, a significantly higher concentration of TGA was stated after using the mixture of herbicides Command 480 EC + Afalon Dispersion 450 SC and Stomp 400 SC + Afalon Dispersion 450 SC.

The aim of this work was to compare herbicide efficacy and reduction of weed reproduction after the application of three frequently used soil residual herbicides during pre-emergent (PRE) and early post-emergent (EPOST) application in maize. Plot field trials were carried out in Central Bohemia during two growing seasons (2010 and 2011). Good efficacy (88%, resp. 83%) was found in isoxaflutole + thiencarbazone (ISF + THC) and terbuthylazin + S-metolachlor (TBA + SMC) on Echinochloa crus-galli, especially in PRE application use. Efficacy on Amaranthus retroflexus was 91% at both tested application periods and there were no significant differences between experimental years. Significant differences in A. retroflexus control were recorded among all tested herbicides (ISF + THC > TBA + SMC > pendimethalin (PEM) + dimethenamid (DMA)). No significant differences between PRE and EPOST were recorded in efficacy on Chenopodium album. Significant differences in efficacy on C. album were recorded among all tested herbicides (ISF + THC > TBA + SMC > PEM + DMA). Mercurialis annua was the most tolerant tested weed, which was significantly better controlled at EPOST herbicide application (73%) compared to PRE application (32%). TBA + SMC showed a significantly higher efficacy on M. annua compared with other tested herbicides. Seed production of all tested weeds was strongly effected by weather conditions, which were significant during 2011, when there was higher than average precipitation during May and June. The most seeds were produced by A. retroflexus > C. album > E. crus-galli > M. annua. ISF + THC best reduced seed production of E. crus-galli, A. retroflexus and C. album, especially when applied at PRE. TBA + SMC best reduced seed production of M. annua. Weed competition on untreated control plots caused yield loss by 90%and 47% in 2011 and 2012, respectively, compared to treatments with the highest yield (ISF + THC).

The present studies determined the antagonistic activity of selected fungi of the soil environment of root chicory -a high-inulin plant, with considerable pro-health values - towards such fungi pathogenic towards this plant as: Altenaria alternata, Botrytis cinerea, Fusarium culmorum, F. oxysporum, Thanatephorus cucumeris and Sclerotinia sclerotiorum. The cultivation of root chicory took into consideration soil mulching with cover crops (oats, tansy phacelia and common vetch) as well as the conventional cultivation, i.e. without any cover crops. The total population of fungi after soil mulching with common vetch was almost twice as small as in the control and smaller than with phacelia as a cover plant. Antagonistic Clonostachys spp., Myrothecium spp., Penicillium spp. and Trichoderma spp. displayed differentiated activity towards the studied fungi. The greatest antagonistic effect was observed after the mulch of oats. Besides, oats and common vetch the most positive effect on the antagonistic activity was that of Clonostachys spp., Myrothecium spp., Penicillium spp. and Trichoderma spp. Those fungi were most effective in inhibiting the growth and development of F. oxysporum, T. cucumeris and S. sclerotiorum.