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A new, effective and economical method to extract ardicrenin from Ardisia crenata Sims collected in the Wolong natural reserve, Sichuan, China, is established. Ardisia crenata Sims powder is counter-current extracted with 80% methanol reflux, decompressively enriched and centrifuged to defat. Supernatant is applied to macroporous resin column (AB-8) with 80% methanol, ardicrenin is isolated by silica gel chromatography with dichlormethane-acetoacetate-methanol (4:1.5:1) washing, and recrystallized in methanol. The final product which proved to be ardicrenin by analytic procedure including Furier transform infrared (FTIR) and ultraviolet spectrum (UV), mass spectroscopy (MS), nuclear magnetic resonance (NMR) and high performance liquid chromatography (HPLC) is white amorphous powder with yield of 1.59 ± 0.02%.

Organic manure is considered as a beneficial fertilizer on soil quality and an excellent alternative resource of chemical fertilizer (CF). However, organic manure from intensive farms may have a negative impact on soil quality because of containing some harmful components, such as heavy metal and antibiotics. The aim of this study was to determine the influence of poultry litter (PL) and livestock manure (LM) from intensive farming on soil physical and biological indicators of soil quality. Results showed that PL and LM amendment increased soil macropore and mesopore volumes and decreased soil micropore volumes. Tensile strength in PL and LM treatment were lower than those in CF, while soil aggregate wet stability index were greater than those in CF. Compared with CF treatment, the microbial biomass C and N contents (+89%, +74%), soil basal respiration rate (+49%) and soil microbial quotient (+45%) in PL and LM treatment were significantly greater. Significant linear correlations were found between soil organic carbon and most soil physical and biological properties (P < 0.01). The results suggested that modern intensive farm manures can be alternate chemical fertilizers as a main fertilizer to improve soil physical and biological indicators in a rice-wheat system.

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.

The objectives of present study were to determine the residual and cumulative effects of zinc (Zn) fertilizer on cotton (Gossypium hirsutum L.) and wheat (Triticum aestivum L.) in a silt loam Typic Haplocambid soil (< 0.05 mg/kg diethylenetriaminepentaacetic acid (DTPA)-Zn). The study comprised of two years field experiments where first cotton crop received zinc sulphate (ZnSO₄∙H₂O) at five rates (0, 5, 7.5, 10, 12.5 kg Zn/ha) in a randomized complete block design with four replications. After harvest, each plot was divided into two sub-plots. To study the residual effect, one sub-plot of all plots did not receive Zn fertilizer for the subsequent crops; however, the other sub-plot received all Zn rates for 2005-06 wheat, 2006 cotton, and 2006-07 wheat. Fresh applied, residual as well as cumulative Zn application significantly (P ≤ 0.05) increased crops production for both experimental years. Residual effect of 5.0 kg Zn/ha optimized the 2006 cotton yield; however, wheat productivity was optimized with residual effect of 7.5 kg Zn/ha in 2005-06 and of 10.0 kg Zn/ha in 2006-07. Optimum yield of both crops was attained with a lesser fresh-applied and residual Zn rate than cumulative Zn rate. Total Zn uptake by wheat (134.9-289.6 g/ha) was much greater than by cotton (92.3-192.5 g/ha). It is concluded that one application of 7.5 kg Zn/ha proved adequate for optimizing two cycles of the cotton-wheat production system. Two-year repeated use of 5.0-7.5 kg Zn/ha did not depress crop yields.

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.

The presented work complements studies on agroclimatic zoning that were performed during 19^{th and 20th century in the Czech Republic and Austria and allows estimating the effect of climate change on the spatial distribution of agroclimatic conditions within both countries. The main conclusions of the study are: (1) The combination of increased air temperature and changes in the amount and distribution of precipitation will lead to significant shifts in the agroclimatic zones by the 2020's. The current most productive areas will be reduced and replaced by warmer but drier conditions, which are considered less suitable for rainfed farming. (2) While trends in the changes expected in lowlands are mostly negative (especially for non-irrigated crops), higher elevations might experience improvement in their agroclimatic production potential. However, the production potential of these regions is usually limited by other factors such as the soil quality and terrain accessibility. Additionally, these positive effects might be shortlived, as by the 2050's, even the areas in higher altitudes might experience much drier conditions than nowadays. (3) Dairy-oriented agriculture (based on permanent grassland production) at higher altitudes could suffer through an increased evapotranspiration demand combined with a decrease in precipitation, leading to higher water deficits and yield variations. (4) All above listed changes will most likely occur within less than four decades. The rate of change might be so high that the concept of agroclimatic zoning itself might lose its relevance due to the perpetual change.}

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.

Water and nitrogen managements are both very important to increase crop yield. An experiment was carried out in split plot design to study the effects of urea types (normal urea and coated urea) and irrigation on soil and fertilizer nitrogen use in maize (Zea mays L.) field in 2006 and 2007. Irrigation was used as main plot, and urea types were used as split-plot. Two irrigation levels, no irrigation in the whole growth duration and 85 mm irrigation at the blister stage, were designed. There were five nitrogen treatments, which were no nitrogen used as control (N0), normal urea 75 kg N/ha (N1), normal urea 150 kg N/ha (N2), coated urea 75 kg N/ha (C1) and coated urea 150 kg N/ha (C2). The results showed that, at the same level of irrigation and nitrogen, the soil nitrogen contents of the treatments with coated urea (CU) applied were higher in 0~40 cm soil layers, but lower in deeper soil layers, than those with normal urea (NU) applied. Irrigation increased the nitrate losing, but the nitrate loss of CU was lower than those of NU. Using CU with irrigation could increase the nitrogen uptake by maize, and more nitrogen was transfered to grain. At the same nitrogen level, CU had higher N recovery efficiency but lower soil N dependent rate than NU. When applied with CU, the nitrogen release rate was lower and the nitrogen was quickly absorbed by maize, which reduced the risk of nitrogen loss and increased the use efficiency of soil and fertilizer nitrogen. These results suggest that coated urea combined with deficit irrigation should be applied for high yield and nitrogen use efficiency of maize on the North China Plain.

The effects of three tillage systems: no-tillage (NT), reduced tillage (RT) and conventional tillage (CT), and three levels of fertilization (0, 258 and 516 kg/ha NPK (58:18:24)), on the maize yield during ten years (1999-2008) were analyzed on the chernozem soil type in Zemun Polje, Serbia. Statistical analyses showed significant effects of all three factors i.e., year, soil tillage and amount of fertilizers, and their interactions on the maize yield. The ten-year averages showed that the highest yields were observed with CT (10.61 t/ha), while the averages with RT and NT were lower (8.99 t/ha and 6.85 t/ha, respectively). The results of the influence of the amount of the applied fertilizers on maize yield showed that the lowest yield was in the zero level of fertilization 7.71 t/ha, while the yield was raised when the 258 kg/ha and 516 kg/ha NPK were applied (9.18 t/ha and 9.56 t/ha, respectively). Analyzing the influence of the soil tillage systems on maize production with respect to the amounts of applied fertilizers, this research revealed the benefits of CT under the presented agroecological conditions, irrespective of the level of applied fertilizer.

Microbial contamination of small streams in agricultural areas was monitored for two years. Microbiological indicators of faecal pollution (faecal coliforms, Escherichia coli and intestinal enterococci were detected by standard methods based on the cultivation of bacteria on selective media). The obtained results showed that running contamination of streams from agricultural areas was not extremely high, but it showed marked seasonal fluctuations (the average values and maximal values revealed great differences). Microbial contamination also increased several times in relation to high precipitation. The water quality in three (and/or four) localities exceeded the acceptable counts of faecal coliforms and enterococci given by the Czech legislation (40 CFU/ml for faecal coliforms and 20 CFU/ ml for enterococci). In agriculturally polluted streams, there were detected more enterococci than faecal coliforms, and also some less frequent species related to farm animals (Streptococcus equines and S. bovis) or plant rests (E. mundtii, E. gallinarum, E. casseliflavus) were present. E. faecalis and E. faecium strains (these are the most common species related to human faecal pollution) were less frequent there.

Morinda citrifolia Linn. (family Rubiaceae) is a small tree occurring in tropical areas of the world. The plant contains several medicinally active components that exhibit the therapeutic effects such as antibacterial, antiviral and anticancer activities. Anti-genotoxic effects of aqueous extracts prepared using dried leaves of M. citrifolia was studied. Allium cepa root tip meristem cells treated with 7% hydrogen peroxide were used for eliciting anti-genotoxicity. For this purpose experiments were performed with A. cepa onion bulbs treated for 24 h with different concentrations (15 or 30 g/L) of aqueous extract with or without pre-treatment (1 h) with 7% hydrogen peroxide. A significant reduction in mitotic index was recorded in treatment groups over negative control. Chromosomal aberrations such as breaks, bridges, stickiness and polar deviations were observed in positive control and treatment groups. The highest (21.48) percentage of chromosomal aberrations was noticed in positive control. A significant reduction in chromosomal aberrations (9.39) was recorded in root tips treated with hydrogen peroxide followed by 15 g/L extract. H₂O₂ induced chromosomal aberrations were reduced due to leaf extract treatment indicates anti-mutagenic potential of the M. citrifolia. The observations suggest that M. citrifolia aqueous leaf extracts have anti-mitotic and anti-genotoxic effects; consequently oxidative stress induced aberrations due to H₂O₂ are efficiently restored in the extract treated A. cepa root meristem cells.

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.

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.

Dynamics of the plant-available potassium (K) has been studied in polyfactorial long-term fertilization experiments since 1980. The fertilization scheme includes 10 combinations of K muriate and farmyard manure application rates (annually 0-230 kg K/ha). At medium treatment (annually 153 kg K/ha), the K balance within an 8-year crop rotation reflected crop specific K application rates with positive annual balances in years of growing silage maize and sugar beet (high K input), and negative in two years of growing alfalfa. Available K clearly corresponded to the dynamics of the K balance, with statistically significant fluctuations from 88 to 149 mg K/kg within one crop rotation cycle. Periodic fluctuations of available K induced by crop rotation were observed also in non-fertilized treatments. The variability of available K contents was influenced primarily by crop plants and experimental unexplained factors; interannual weather fluctuations and field differences were of low significance. In the paper, the importance of interannual K dynamics for the construction of correct long-term time trends is shown and discussed.

To investigate the environmental advantages of using grass-clover binary mixtures over pure stands as winter cover crops, a serial of five field experiments (each designed as randomized complete blocks with four replicates) was carried out in eastern Slovenia. Trifolium incarnatum L. and Lolium multiflorum Lam. were sown in late summer as pure stands and binary mixtures. Pooled data calculated from all the experiments revealed that the soil mineral N in spring and accumulation of N by plants decreased with decreasing proportion of T. incarnatum in the binary mixtures, while the C:N ratio of cover crop organic matter increased. C accumulation was the highest when the seeding ratio of the binary mixture of T. incarnatum and L. multiflorum was 50:50. In the C and N environmentally sustainable management efficiency coefficients, three important traits of winter cover crops for environmental pro-tection were given equal importance (low soil mineral N content in spring, high C accumulation in plants, and high N accumulation in plants). The coefficient was higher for binary mixtures of T. incarnatum and L. multiflorum than for pure stands of these crops, proving the complex environmental advantages of binary mixtures over pure stands.

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.

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.

Caragana microphylla Lam., an indigenous leguminous shrub, was the dominant plant species to be used to control desertification in semi-arid Horqin Sandy Land. To elucidate the cover effect of Caragana microphylla planted for 25 years on spatial distribution of soil nutrients including C, N, P and K, soil samples were taken from four soil depths (0-5 cm, 5-10 cm, 10-20 cm, and 20-40 cm) and three slope positions (windward slope, top slope, and leeward slope). Soil nutrients under shrubs (US) and between shrubs (BS) were compared to investigate the enrichment effect of plantation. The results showed that soil nutrients except total K were significantly higher in surface soil (0-5 cm) than in deeper layer soil (P < 0.01). Significant differences were found in the contents of total organic carbon, total nitrogen, total phosphorus, and total K at different slopes. The contents of total organic carbon and total nitrogen were higher in US than in BS (P < 0.05), but pH was lower (P < 0.01). Our results indicated that the establishment of Caragana microphylla increased the accumulation of soil nutrients, and played an important role in restoring sand dune ecosystems.

We have tested the effect of water, methanol and dichloromethane extracts from the leaves of several species of Impatiens (I. noli-tangere, I. parviflora, I. glandulifera) on germination of seeds Leucosinapis alba and Brassica napus. All of the tested extracts had inhibitory effects to seeds of all studied plants (except the dichloromethane extracts). The highest activity revealed methanol extract and extract from I. glandulifera.

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.

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.

Little is known about the effects of air-drying and freezing on the transformation of phosphorus (P) fractions in soils. It is important that the way in which soils respond to such perturbations is better understood as there are implications for both P availability and loss to surface waters from soils. In this study, the effects of air-drying and freezing were investigated using two soils, one being a forest soil (FS) high in organic matter and the other being a sterile soil (SS) low in organic matter. Soil P was fractionated using a modified Hedley fractionation method to examine the changes of phosphorus fractions induced by air-drying and freezing. Generally, there were no significant differences of total phosphorus among the three treatments (CV% < 10%). Compared with field moist soils, freezing the soil evoked few changes on phosphorus fractions except that the resin-P increased in FS soil. On the contrary, air-drying significantly changed the distribution of phosphors fractions for both soils: increased the labile-P (especially resin-P) and organic-P (NaHCO₃-Po, NaOH-Po and Con.HCl-Po) at the expense of NaOH-Pi and occlude-P (Dil.HCl-P and Con.HCl-Pi). Resin-P significantly increased by 31% for SS soil and by 121% for FS soil upon air-drying. The effect of air-drying seemed to be more pronounced in the FS soil with high organic matter content. These results indicated that drying seem to drive the P transformation form occlude-P to labile-P and organic-P and accelerated the weathering of stable P pool. This potentially could be significant for soil P supply to plants and P losses from soils to surface waters under changing patterns of rainfall and temperature as predicted by some climate change scenarios.

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.

The present investigation was conducted to know the impact of bio-inoculants in low input field conditions on the magnitude and direction of gene effects and mean performance of some morphological and productivity traits in three wheat cultivars WH 147 (medium mineral input), WH 533 (drought tolerant), Raj 3077 (drought tolerant) and six generations namely P₁, P₂, F₁, F₂, BC₁ and BC₂ of three crosses i.e. WH 147 × WH 533, WH 533 × Raj 3077 and WH 147 × Raj 3077. The experiment was conducted in randomised block design with three replications and three treatments i.e. control (C, without inoculation), inoculation with arbuscular mycorrhiza fungi (AMF, Glomus fasciculatum), and AMF + Azotobacter chroococcum (Azc). Mineral fertilizer (80 kg N/ha + 40 kg P/ha + 18 kg ZnSO₄/ha) was applied in all the three treatments. The application of bio-inoculants, AMF and AMF + Azc had a positive effect on plant height, peduncle length, grain yield, biological yield and harvest index in various populations of all the crosses. However, in some of the generations the impact of bio-inoculants was insignificant. The joint scaling test revealed that additive-dominance gene effects were mainly operative in governing expression of peduncle length, tillers per plant, plant height, grains/spike, grain yield and all traits except days to flowering and harvest index in crosses WH 147 × WH 533 and WH 533 × Raj 3077. The application of bioinoculants influenced gene effects for days to flowering, days to maturity, flag leaf area, spike length, grains/spike, 1000 grain weight and harvest index where complex genetic interactions were changed to simple additive-dominance gene effects in the cross WH 147 × Raj 3077. Likewise, additive-dominance gene effects were altered and digenic interactions exhibited for days to maturity, flag leaf area in WH 147 × WH 533 and days to flowering, plant height, flag leaf area in WH 533 × Raj 3077. Flag leaf area and plant height were governed by additive gene effects while for days to maturity and 1000-grain weight both additive and dominance gene effect were important. Duplicate epistasis was important in all the three crosses for days to flowering and harvest index and in the cross WH 147 × Raj 3077 for grain weight grains per spike and flag leaf area.

The aim of this work was to estimate the changes in contents of different sulfur (S) fractions in soils under conditions of lowering inputs of S from emissions together with the influence of application of manure and mineral fertilizers. Soil samples from long-term field experiments were used for this purpose. The samples were taken from 10 sites from precise long-term field experiments with different soil-climatic conditions in the Czech Republic. The samples were analyzed using the following fractionation: (i) water soluble S (H₂O extracts), (ii) sorbed S (0.032M NaH₂PO₄ extracts) and (iii) S occluded with carbonates (1M HCl extract). Furthermore, the concentration of total S (S_tot) and organic S (S_org) was determined. Soil samples were taken in the years 1981 and 2007. During 26 years a decrease of S_tot by about 3-8%, water soluble S by 65-68% and sorbed S by 39-44% were observed in the topsoil of the evaluated soils. Furthermore, a low increase in the content of organic S was observed. The estimated ratio of S_org reached 78.7-80.9% from S_tot in the year 1981 and 87.7-89.8% in 2007. Farmyard manure (40 t/ha) applied every 4 years did not have a significant influence on S fractions and S_tot contents in soils; intensive S fertilizing increased S_tot and mobile S forms contents in soils. Very close correlations were obtained especially between S_tot and water soluble S and organic S.

Evaluation of the nutrient status in soil is important for nutritional, environmental, and economical aspects. The objective of this study was to determine potassium (K) available to Pinto beans (Phaseolus vulgaris) in 15 soils from the Charmahal Va Bakhtyari province. The treatments included two K levels [0 and 200 mg K/kg as potassium sulfate (K₂SO₄)] and 15 soils in a factorial experiment in a randomized block design with three replications. The results indicated that in some soils K application increased yield, K concentration and K uptake by bean. The 9 extracting solutions used in this study were classified in 4 groups on the basis of the mechanism of the extraction. The first group of extractants were acidic extractants, boiling 1 mol/L HNO₃, 0.1 mol/L HNO₃, 0.1 mol/L HCl, and Mehlich 1. The second group includes 0.1 mol/L BaCl₂, and 0.01 mol/L CaCl₂. The third group includes 1 mol/L NH₄OAc (ammonium acetate), and AB-DTPA (ammonium bicarbonate-diethylenetriamine pentaaceticacid), and finally distilled water. The correlation studies showed that NH₄OAc, AB-DTPA,0.1 mol/L BaCl₂, 0.1 mol/L HCl, and boiling 1 mol/L HNO₃ could not be used as available K extractants. But the correlation of other extractants with relative yield, plant response, concentration K, and K uptake were significant. Therefore, these extracting solutions can be used as available K extractants. Potassium critical levels by extractants were also determined by Cate-Nelson method. Potassium critical levels for 90% of relative yield were 22, 190, 28, and 50 mg/kg for distilled water, 0.1 mol/L HNO₃, Mehlich 1, and 0.01 mol/L CaCl₂, respectively.

Non-invasive determination of deoxynivalenol (DON) still presents a challenging problem. Therefore, the present study was aimed at a rapid determination of DON in whole wheat grain by means of FT-NIR spectroscopy, with a wide range of concentrations for potential applications in breeding programs and common systems of quality management using partial least square calibration (PLS) and discriminant analysis technique (DA). Using a set of artificially infected wheat samples with a known content of DON, four PLS models with different concentration range were created. The broadest model predicting DON in the concentration range of 0-90 mg/kg possessed the highest correlation coefficients of calibration and cross validation (0.94 and 0.88); but also possessed the highest prediction errors (SEP = 6.23 mg/kg). Thus the subsequent combination of DA as the wide range predictive model and the low-range PLS model was used. This technique gave more precise results in the samples with lower DON concentrations - below 30 mg/kg (SEP = 2.35 mg/kg), when compared to the most wide-range PLS model (SEP = 5.95 mg/kg).Such technique enables to estimate DON content in collections of artificially infected wheat plants in Fusarium resistance breeding experiments.

Adjuvants are surface active agents that are added to pesticide formulations or tank-mix to facilitate the mixing, application, or efficacy of these products. Addition of adjuvants changes the physico-chemical properties of spray liquid. In this work, we have focused in particular on surface tension and density of aqueous solutions of different adjuvants registered for mixing with herbicides. Eleven different adjuvants were subject of this study under laboratory conditions. An equation which enables determination of density of aqueous solutions in concentration range of 0-15 g/kg was designed. Average difference between the experimental and calculated density values amounts to ± 0.006%. The concentration dependence of surface tension was utilized to determine the critical micelle concentration (cmc). Evidently, the cmc of most tested adjuvants was lower than the amount recommended by manufacturer, especially in case of adjuvants Dedal 90 EC and Mero 33528. For adjuvant Trend 90 EC the recommended rate is even lower than that obtained for the cmc. Maximum reduction of the surface tension of water was achieved with adjuvants Silwet L-77 and Break Superb.

In the present study the impact of beauvericin (BEA) on the cell membrane properties and respiration of young initial leaves of maize were studied using two maize cultivars differing in their susceptibility to Fusarium sp. BEA significantly depolarized E_M of leaf parenchymal cells and this depolarization showed time and dose dependency regardless on the sensitivity of maize cultivars to Fusarium. However, the extent of BEA-induced depolarization was 2-5 times higher in sensitive cv. Pavla than in tolerant cv. Lucia. Membrane permeability and K⁺ leakage from leaves cells treated with BEA was higher in sensitive cv. Pavla but the differences were not so considerable than the depolarization of E_M. Treatment of maize young initial leaves with 40 μmol BEA significantly inhibited respiration. In accord with electrophysiological measurements inhibition of respiration was higher in sensitive cv. Pavla showing 70% inhibition already after 90 min of BEA treatment while in tolerant cv. Lucia inhibition represented only 27%. The biological activity of BEA seems to be mediated by the ability of BEA to affect membrane permeability and ion transport. This is probably the initial effect of BEA on plant cell leading to subsequent effect on other cell organelles (mitochondria) and cell metabolism.

The greenhouse experiment was performed to determine Cu release characteristics in the bulk and the rhizosphere of some calcareous soils using rhizobox. The kinetics of Cu release in the bulk and the rhizosphere soils were determined by successive extraction with diethylenetriaminepentaacetic acid-triethanolamine (DTPA-TEA) and 10 mmol/L citric acid in a period of 1 to 504 h at 25 ± 1°C. The results of kinetics study showed that Cu extracted using DTPA-TEA in the rhizosphere soils was significantly (P < 0.01) lower than the bulk soils, while Cu extracted using citric acid in the rhizosphere soils was significantly (P < 0.01) higher than the bulk soils. The mean of released Cu after 504 h using DTPA-TEA were 8.59 and 7.46 mg/kg in the bulk and the rhizosphere soils, respectively. The mean release of Cu after 504 h using citric acid was 14.73 and 16.05 mg/kg in the bulk and the rhizosphere soils, respectively. Release kinetics of Cu in two extractants conformed fairly well to parabolic diffusion, power function, and first order equations. The results of correlation analysis illustrated that a significant correlation between Cu desorption after 504 h with citric acid and Cu concentration in wheat was found (r = 0.96 and r = 0.90 in the rhizosphere and the bulk soils, respectively, P < 0.01). Therefore, application of 10 mmol/L citric acid extractant would be recommended in the future study on the kinetics of release of Cu in calcareous soils.