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The stability of plant nuclear genome is a necessary condition for the faithful transmission of genetic information through cell lineages. When DNA damage occurs due to various impairments, cells start a number of repair processes including ligation of broken chromosomes. As a result, dicentric chromosomes can be formed. Dicentrics are easily detectable as anaphase bridges during following mitosis. Using Arabidopsis as a model plant, we developed a sensitive cytogenetic assay to identify specific chromosomal rearrangements. Here we show Arabidopsis tert^-/- and atm^-/- mutants and their chromosome rearrangements and fusions analysed by fluorescence in situ hybridization (FISH). The method is based on successive rounds of FISH with chromosome-specific probes and the comparison of resulting FISH images.

The effect of three seedling treatments: T₀, normal germination; T₁, cotyledons removed; T₂, cotyledons removed 5 days earlier than in T₁; and two phosphorus levels (P₀ and P₃₀) on nodulation and nodule function in soybean [Glycine max (L.) Merr.] were investigated in nutrient solution culture. The number of nodules formed at P₀ was in the order T₂ > T₀ > T₁, but it was T₀ > T₂ > T₁ at P₃₀. Nodule dry weight per plant had the same tendency as the nodule number. Nodule size (dry weight per nodule) in seedlings ranged from 0.601 to 1.089 mg in the order T₀ > T₁ > T₂, regardless of P level. For example, nodule size in T₀ was larger by 86% and 52% than T₂ at P₀ and P₃₀, respectively. Furthermore, regardless of P level, a specific acetylene reduction activity (ARA, µM C₂H₄/h/g nodule) increased with P content in seedlings, but no significant difference was found (P < 0.05). Leghemoglobin (Lb) content was not significantly affected by P level; however, seedlings (T₀ and T₁) significantly affected the Lb content per unit plant biomass (P < 0.05). All these results suggest that seedling P content plays a key role in nodulation and nodule function of soybean.

Spring wheat var. Vánek was cultivated in pots in a soil naturally contaminated with heavy metals. Experimental plants were treated with three different types of brassinosteroids (BRs; 24-epibrassinolide, 24-epicastasterone and 4154) during two different growth stages 29-31 DC (off shooting) and 59-60 DC (beginning of anthesis). Content of heavy metals (Cu, Cd, Pb and Zn) was determined using AAS method in the plant growth stages 47-49 DC (visible awns), 73-75 DC (30-50% of final grain size) and 90-92 DC (full ripeness). At the stages 47-49 DC and 73-75 DC, the content of the heavy metals was determined in the biomass of whole plants, while at the stage 90-92 DC it was determined separately in straw and grains. After the treatment of plants with BRs a decrease in heavy metals content was observed in the growth stage 73-75 DC (i.e. during the period when the plants are harvested for ensilage purposes. Likewise, a decrease of lead content in the grains by 70-74% in the plants treated at both stages 29-31 DC and 59-60 DC and by 48-70% in the plants of the third group (plants treated at stage 59-60 DC) was determined as compared with the untreated plants.

In Europe, Rumex obtusifolius L. is the most problematic grassland weed species, especially under the conditions of organic farming. The aims of this study were (1) to investigate the effectiveness of repeated mechanical weeding of R. obtusifolius from the permanent sward, cut two or three times per year, by digging the plants out from 5 cm below the soil surface, and (2) to test the effect of nutrient availability on the effectiveness of mechanical weeding. In 2007, the manipulative experiment was established on permanent grassland infested by R. obtusifolius using the following fertilizer treatments: control, P, N, NP and NPK. Plants of R. obtusifolius were removed eight times during three vegetation seasons. No significant decrease in the density of R. obtusifolius was recorded after three vegetation seasons and density was not significantly affected by fertilizer treatment. The cover of R. obtusifolius decreased slightly, but significantly, over the study period from 7.5% to 4.5%. The cover of R. obtusifolius was only marginally affected by fertilizer treatment. Mechanical weeding by digging the plants out from 5 cm below the ground is not a sufficient method of control for R. obtusifolius in infested fertile grasslands, even when applied eight times during three vegetation seasons.

The paper presents selected information on the newest results of a wide investigation of the state of information and communication technologies development in agricultural production enterprises in the Czech Republic. The investigation was realized in the first half of 2009 with the main aim to analyze development of information infrastructure and actual trends in ICT use in rural regions where most entrepreneurial subjects operate. Besides a presentation of own research results, some obtained pieces of knowledge are then commented and eventually discussed in connection with official outputs of the Czech Statistical Office (CSO), if they have a certain relevance to the given problems.

Arbuscular mycorrhiza is a mutualistic association between fungi and higher plants, and play a critical role in nutrient cycling and stress tolerance. However, much less is known about the mycorrhiza-mediated enhancement in growth and salinity tolerance of the peanuts (Arachis hypogaea L.) growing in the arid and semi-arid areas. Therefore, mycorrhizal status of Glomus mosseae in diverse salinity levels on original substrate soil conditions was investigated. Different growth parameters, accumulation of proline content and salt stress tolerance were studied. These investigations indicated that the arbuscular mycorrhizal fungi could improve growth of peanuts under salinity through enhanced nutrient absorption and photosynthesis. Chlorophyll content and leaf water content were increased significantly under salinity stress by the inoculation with mycorrhizal fungi. Tolerance of the plants to salinity was increased and the mycorrhizal association was found highly effective in enhancing peanut growth and establishment in soils under salinity and deficient in phosphorus.

Soil microbial biomass is a dynamic force driving soil phosphorus cycling in soils. The temperature, time and method for killing soil organisms in soil biomass P determination are so important factors that affect the results. The aim of this study was to compare some methods of soil sterilization and soil microbial P (Pm) release in extraction with NaHCO₃. Five samples of calcareous soils in three replicates were incubated in field capacity and 28°C. The texture of soils differed from loamy sand to sandy loam. They had 10-15% equivalent calcium carbonate, 1-3% organic carbon and 40-90 mg/kg available P content. After 1, 10, 30, and 50 days of incubation a portion of each soil was sterilized by five methods (chloroform fumigation, autoclaving at 121°C for 0.5 h, oven drying at 70°C for 48 h, oven drying at 180°C for 2 h, and ultrasonification). Phosphorus of the sterilized and control soils were extracted with 0.5M NaHCO₃ (pH 8.5) and determined spectrophotometrically as blue molybdate-phosphate complexes under partial reduction with ascorbic acid. Results showed that the method of soil sterilization and soil type had significant effects on biomass P estimated in soils (P < 0.01). There were no significant differences between extracted biomass P at chloroform fumigation, autoclaving at 121°C for 0.5 h, and oven drying at 70°C for 48 h. However biomass P was significantly more extracted from soil by oven drying at 180°C for 2 h and by ultrasonification. Fixation of Pm in soil during the extraction period can reduce the precision of biomass P estimates. This effect was more obvious in biomass P determination by fumigation and oven drying at 70°C for 48 h. Biomass P determined by these methods and autoclaving had positive and significant correlations with soil sand contents, respectively due to long sterilization period and temperature. Ultrasonification released more P from these calcareous soils especially at the start of soil incubation. It released higher microbial P and reduced P sorption in soils; biomass P determined by this method compared to other methods had relatively higher correlations with fungi, glumales spore and P solubilizing bacteria numbers in soil.

The influence of mechanized cutting time on the yield and quality of hops was studied for three years (2007, 2008 and 2009) in three Czech hybrid varieties Harmonie, Rubín and Agnus. The cutting term classified as 'early' was carried out at the turn of March and April. Further cutting dates were made at intervals of 7-10 days and they were classified as 'middle' and 'late' ones. Yield and contents of alpha acids were evaluated during the machine harvest. The measured data revealed no statistical relationship between term of cutting, alpha acid content and yield in any of the tested cultivars. However, during the experimental period considerable inter-annual differences were observed, especially in the yield. Average yield in the range of 2.0-2.5 t/ha in the period 2007-2008 decreased to 1.2-1.9 t/ha in 2009 due to downy mildew attack. On the basis of the obtained data it can be recommended to cut the hybrid varieties Harmonie, Rubín and Agnus in the first ten days of April, taking into account other factors such as age and the location of hop garden and current weather conditions.

To better understand how water stress and availability affect the enzyme activity and microbial communities in soil, we measured the changes of organic carbon (OC), bacteria and fungi populations, and endoglucanase and exoglucanase activities in a semiarid soil treated with air-dried primary sewage sludge at a rate of 20 g/kg. The water potentials established for soil incubation were: saturation (SA, 0 bar), field capacity (FC, -0.3 bar), and permanent wilting point (PWP, -15 bar). An irrigation treatment was a drying-rewetting cycle (DWC) between -0.3 to -15 bars. After 0, 20, 60 and 90 days of incubation soils were sampled for analysis. The addition of sewage sludge increased soil OC, endoglucanase and exoglucanase activities significantly. The effects of soil moisture, incubation time and their interactions on OC, and endoglucanase and exoglucanase activities in soil were significant. During 20 days of incubation, OC, endoglucanase and exoglucanase activities decreased significantly. Soils incubated in DWC and FC compared to soils incubated in SA and PWP had lower OC contents due to organic matter mineralization. Organic C, exoglucanase and endoglucanase activities significantly increased with increasing soil water potential. The activities of exoglucanase and endoglucanase in soils incubated in SA were significantly higher than those in soils incubated in PWP.

Yields of winter wheat, winter rape and oats were evaluated in the field; the field was divided into the site-specific zones and treated with variable doses of nitrogen fertilizer in years 2004-2006. Measurements of the yields were carried out with a yield monitor placed in a combine harvester. The measured data were processed into the yield maps by means of ArcGIS 9.2 software. Variable application of fertilizer should balance yield potential of the field. Generally, total yield variability on the field after the application of various doses of experimental fertilizer was similar in the years 2004 (11.3%), 2005 (14.7%) and 2006 (11.7%) in comparison with the year 2003 (25.02%). Variable application of nitrogen in the site-specific zones, created on the basis of the yield levels, decreased the yield variability in comparison with the uniform dose. Different doses of nitrogen fertilizer also enabled to increase utilization of production potential of the experimental field.

Soybean cultivation in many zones of India shows occurrence of native rhizobia besides other exotically adapted strains. In the current study, 22 rhizobial isolates (recovered from 12 different soybean growing sites) and 8 reference strains were selected for biochemical and metabolic characterization. Of 22 isolates, 18 were recovered as fast growing isolates while the rest were slow growing based on bromothymol blue (BTB) test. Unlike earlier belief that rhizobia have no ability to grow on glucose peptone agar medium, in this study, some isolates and some reference strains grew well on this medium. Similarly, when all the isolates were subjected to ketolactose test, some of the isolates were found to show growth on the medium. In contrast, based on C-utilization pattern (15 carbohydrates) a remarkable metabolic diversity was observed among the rhizobial isolates recovered in the study. The clustering and matching analysis showed that most of isolates were matching with slow growing reference strains, a few were with fast growing reference strains and some were found to be unique and hence not matching with any of reference strains. Such analysis suggests the occurrence of metabolically distinct types of rhizobia besides commonly known types (B. japonicum, B. elkanii and S. fredii) of soybean rhizobia and further validation is suggested through 16SrRNA gene sequencing technique.

Microarray analysis is a cultivation-independent, high-throughput technology that can be used for direct and simultaneous identification of microorganisms in complex environmental samples. This review summarizes current methodologies for oligonucleotide microarrays used in microbial ecology. It deals with probe design, microarray manufacturing, sample preparation and labeling, and data handling, as well as with the key features of microarray analysis such as specificity, sensitivity and quantification potential. Microarray analysis has been validated as an effective approach to describe the composition and dynamics of taxonomic and functional microbial communities, in environments including soil, compost, sediment, air or humans. It is now part of the technical arsenal available to address key issues in microbial community ecology, ranging from biogeography to ecosystem functioning.

A 2-year field experiment was conducted under light enrichment and shading conditions to examine the responses of seed yield and yield components distribution across main axis in soybean. The results showed that the maximum increase in seed yield per plant by light enrichment occurred at 27 plants/m², while the most significant reduction in seed yield per plant by shading occurred at 54 plants/m². Light enrichment beginning at early flowering stage decreased seed size on average by 7% while shading increased seed size on average by 9% over densities and cultivars, resulting in a fewer extent compensation in seed yield decrement. Responses to light enrichment and shading occurred proportionately across the main axis node positions despite the differences in the time (15-20 days) of development of yield components between the high and low node positions. Variation intensity of seed size of three soybeans was dissimilar as a result of changes in the environment during the reproductive period. The small-seed cultivar had the greatest stability in single seed size across the main axis, followed by moderate-seed cultivar, while large-seed cultivar was the least stable. Although maximum seed size may be determined by genetic potential in soybean plants, our results suggested that seed size can still be modified by environmental conditions, and the impact can be expressed through some internal control moderating the final size of most seeds in main stem and in all pods. It indicates that, through redistributing the available resources across main stem to components, soybean plants showed the mechanism, in an attempt to maintain or improve yield in a constantly changing environment.

The response of blackgram (Vigna mungo L. Hepper) to two levels of elevated carbon dioxide (550 and 700 ppm) in terms of growth and yield was investigated and compared with ambient CO₂ level (365 ppm) using open-top chambers. The growth parameters viz., length and weight of root and shoot, root:shoot ratio, leaf area and weight significantly increased at 700 ppm CO2 when compared with 550 ppm. The percentage increase in total biomass at 700 and 550 ppm CO₂ was 65.4% and 39%, respectively compared to the ambient (chamber) control. The increase in total seed yield at 700 ppm (129%) was due to an increase in number of pods per plant and 100 seed weight, whereas at 550 ppm (88.7%) it was due to an increased number of pods/plant and seeds/pod. The results indicate variable responsive effects at different levels of CO₂ emphasizing the pertinence of research on elevated CO₂ in various agroecological inhabitations all over the world. The indication of higher responses for root and leaf at initial growth stages at the higher elevated level of CO₂ (700 ppm), which leads to better root establishment, achieving early photosynthetic efficiency and also better biomass production, and its improved partitioning can be reckoned as a positive aspect of increasing concentrations of CO₂ in atmosphere. The harvest index increased significantly to 35.7 and 38.4% at 550 and 700 ppm, respectively; it is a very important phenomenon in pulses for breaking the yield barrier.

Limited information is available regarding the source-sink alterations on soybean yield under whole plant light enriched conditions. The differential responses of yield components for two old and two new cultivars were investigated. The yield sensitivity of the old cultivars to the changes in source strength and light enriched conditions was much greater than that of the two new cultivars. The yield of the new cultivars was more likely sink-limited, and source-limited for the old cultivars. The increased yield by light enrichment was in part due to an increased branch contribution. Pod number per plant was more responsive than seed number per pod. The reduction in pod number by source-sink manipulation was more severe in the old cultivars. Light enrichment increased pod number in the two old cultivars but not in the two new cultivars. Seed size was responsive to changes in the source-sink ratio and changes in the environment. Both pod number or seed size may be increased or decreased if environmental conditions for seed filling are altered.

This study compares effects of 2,3,5-triiodobenzoic acid (TIBA) and flavonoid quercetine (Q). In spite of the fact that both these compounds are inhibitors of the polar transport of auxin, a number of experiments demonstrated that their properties are different. If the flax seedlings were decapitated and one cotyledon was removed, the axillary bud of the remaining cotyledon grew up more intensively while TIBA (0.5% applied in the form of a lanolin paste on the remaining cotyledon) induced a correlative reversal so that axillars of removed cotyledons grew up more intensively. However, when Q (0.5%) was applied on the remaining cotyledon in the form of a lanolin paste, this inhibition was not significant. In the lamina-deprived petioles of apple trees TIBA accelerated abscission while Q caused an inhibiting effect similar to that of auxin. TIBA applied on epicotyls of pea seedlings inhibited their growth by 35% while Q only by 15%. As far as the release of ethylene by pea seedlings is concerned, both compounds showed promoting effects similar to the effect of auxin.

An interrelationship between introduced and indigenous rhizobia focused on their competitiveness in nodulation was evaluated in a soil pot experiment. Clover seeds were inoculated by six different gradual concentrations of inoculum of two effective Rhizobium leguminosarum bv. trifolii isolates (inoculation strains 1/2 and 14/2). At the beginning of flowering, clover plants were removed from the pots, and nodules from each pot representing different degrees of inoculum level were taken for reisolate cultivation. The PCR technique was used for the identification of rhizobial reisolates, random amplified polymorphic DNA product patterns were acquired and analysed. Nodule occupation by inoculation strains or indigenous Rhizobium leguminosarum bv. trifolii strains was assessed by comparing the number of nodules formed by inoculation or indigenous strains and inoculation strains competitiveness was calculated. Nodule occupancy by the inoculation strain 1/2 increased sharply with the increase in inoculum dose, whereas in inoculation strain 14/2 more nodules were formed gradually starting from low inoculum level. Competitiveness of inoculation strain 1/2 was calculated as low and was documented by an absence of nodule occupancy in four inoculation levels. On the other hand, competitiveness of the inoculation strain 14/2 was considerably higher, and even in low inoculum dose this strain was more competitive than native rhizobia. Although both the inoculation strains 1/2 and 14/2 were found highly efficient in nitrogen fixation, only the strain 14/2 was able to manifest this characteristic due to the higher competitiveness when applied in lower doses.

This work proposes a new method for the assessment of species richness, diversity, and homotony in related vegetation relevés of grass swards. Hypothetical vegetation relevés with identical species number but differing constancy were generated to compare the techniques describing the species variety and diversity. By calculating these theoretical values in combination with data from real swards of Alopecuretum meadows, it has been shown that the determination of the constancy of particular species is essential for the evaluation of species diversity of grass swards. The relationship between the share of different combinations of vegetation relevés in the whole sample and corresponding total number of plant species were expressed by generating regression equations and the mid values of these curves were worked out and evaluated for individual sets of relevés; it was then possible to create homotony/heterotony indices for these sets. The indices of heterotony can be used, e.g., for expressing biotope diversity within a set of vegetation relevés from different stands.

In a microplot experiment conducted in 1999 and 2000 on light soil triticale and field beans were grown as sole crops and in the intercrop system. Two pure stand plant densities were established: 200 and 400 plants/m² for triticale and 50 and 100 plants/m² for field beans. Four possible intercropping combinations were obtained by adding densities of both crops. Triticale was a better competitor than field beans in all intercrops resulting in competitive balance index significantly greater than zero. The number of pods per plant of field beans was significantly reduced in all intercropping combinations compared to the pure stands, however quality of grain of the legume was unaffected by competition. Intercrop comprising 200 plants/m² of triticale and 50 plants/m² of field beans was most productive in the experiment but addition 50 more plants/m² of the legume decreased significantly grain yield of intercrop by 16.2%. The results also show that effective triticale-field beans intercrop for light soil may be designed as additive one, based on 400 plants/m² of triticale.

The growth and yield response of spring wheat to inoculation with foreign and local rhizobacteria of Erzurum (Turkey) origin was studied. At the first stage of the research, a greenhouse experiment was carried out with wheat cv. Kirik using 75 local bacterial strains isolated from the soil with 6 foreign bacteria, and a control. According to results of the greenhouse experiment 9 local strains were identified. At the second stage, the response of wheat cv. Kirik to 20 treatments (9 local strains, 6 foreign bacteria, 4 levels of N, and a control) was investigated in Erzurum field conditions. Seventeen strains had significant positive effects on tiller number per plant, 47 strains on plant height, one strain on dry matter yield, and 28 strains on plant protein content in the greenhouse experiment. Inoculation with certain rhizobacteria clearly benefited growth and increased the grain and N-yield of field grown wheat. The effects of local strains were observed to be in general superior to those of foreign strains. Inoculation with the local Strain No. 19, 73, and 82 increased total biomass by 18.7, 18.1, and 19.9%; grain yield by 18.6, 17.7, and 18.0%; total N-yield by 27.5, 24.3 and 26.0%, respectively, as compared to control. In conclusion, Strain No. 19, 73, and 82 can be a suitable biofertilizer for spring wheat cultivation in areas with similar conditions as in Erzurum. Inoculation with these strains may lead both to increases in wheat yield and savings of nitrogen fertilizer.

Quality assurance is a major issue in the food industry. The authenticity of food ingredients and their traceability are required by consumers and authorities. Plant species such as barley (Hordeum vulgare), rice (Oryza sativa), sunflower (Helianthus annus), wheat (Triticum aestivum) and maize (Zea mays) are very common objects of interest of genetic modification (GMO); therefore the development of specific assays for their specific detection and quantification of GMO are needed. Furthermore, the production and trade of genetically modified lines from an increasing number of plant species brings about the need for control within research, environmental risk assessment, labeling-legal, and consumers' information purposes. Electrochemical sensors and biosensors based on modification of working electrode could be suitable tools for these purposes. Here, we report using of an avidin-modified carbon paste electrode for rapid and sensitive determination of avidin in plant extract solution and in a transgenic maize extract. The process could be used to determine avidin concentrations up to 3pM in solution and 170nM in a maize seed extract. Moreover, we applied the method to analyze different maize flours.

In this research cyanobacteria (Blue-Green Algae, BGA) were isolated, identified, multiplied and used as an inoculum in pot rice experiment. The pH, moisture and algal population were measured in four seasons. The highest and lowest pH (6.7, 6.2), moisture of soil (43%, 34%) and algal population (12, 20 Colony-Forming Units/50 ml on A and B medium and 4, 5 Colony-Forming Units/50 ml on A and B medium) were recorded in spring and winter, respectively. The only heterocystous cyanobacteria were found in soil samples identified as Anabaena with four species (A. spiroides, A. variabilis, A. torulosa and A. osillarioides). The germination of rice seeds treated with cyanobacteria was faster than control. The result of pot experiment were: increase of 53% in plant height; 66% in roots length; 58% in fresh leaf and stem weight; 80% in fresh root weight; 125% in dry leaf and stem weight; 150% in dry root weight; 20% in soil moisture; 28% in soil porosity and a decrease of 9.8% in soil bulk density and 4.8% in soil particle density. There were significant differences (P < 0.05) in pot treated with BGA as compared with control.

The effect of diesel oil applied at 0, 2.4, 4.8 and 7.2 ml/kg of soil on yield of oat and number of oligotrophic, eutrophic, nitrogen immobilising, ammonifying and cellulolytic bacteria and Azotobacter sp., actinomyces and fungi was studied in a pot experiment. Inoculation with Streptomyces intermedius spores was used for soil detoxication. The experiment was performed in Eutric Cambisol soil derived from light clay sand. Diesel oil was found to have a negative effect on the growth and development of oat. Inoculation did not attenuate the response of oat to soil contamination with diesel oil, but it had a positive effect on oligotrophic and eutrophic bacteria as well as Azotobacter sp., nitrogen immobilising bacteria and fungi. Regardless of sown and unsown soil and inoculation with S. intermedius spores, diesel oil stimulated the number of oligotrophic, eutrophic, nitrogen immobilising bacteria and actinomyces. Sowing of oat positively affected microbiological properties of soil, because it had a positive influence on the relation of oligotrophic bacteria and actinomyces to fungi. This positive effect, however, was weakened by diesel oil.

Improvement in leaf hydraulics is directly related to the improvement of plant tolerance to drought stress. Therefore, a field and pot experiment was carried out to determine the type of genetic variability and selection of parental types on the basis of combining ability for leaf hydraulics. Genotypes showed similar performance in both experiments; higher values were shown by drought tolerant genotypes in all traits except for osmotic potential, which drought tolerant genotypes maintained lower. Osmotic adjustment in pot experiment showed the highest magnitude of additive type of genetic variability. Female showed a higher and significant contribution of general combining ability effects as compared to male; it suggests that within genotypes female rather than male mostly contribute for additive genes. AMES-10103 showed the highest general combining ability effects for traits such as turgor pressure and osmotic adjustment.

Sustainable land management requires that water and matter (nutrients and base cations) are efficiently recycled within ecosystems so that irreversible losses of matter from topsoils are minimised. Matter losses are connected to water flow. The division of water into evapotranspiration that is loss-free, and seepage to groundwater or surface water flow that both carry material losses, is decisive in determining total losses of dissolved matter in a given catchment. Investigations of areal matter losses confirmed the instrumental role of vegetation cover. Areal matter losses measured in agricultural catchments in Germany were on average between 1-1.5 tons of dissolved matter per ha per year, i.e. some 50 to 100 times higher than those from unmanaged land in a virgin forest. Such high losses continuously reduce soil fertility and can hardly be compensated by fertilisation. Some suggestions on how to achieve sustainable management of agricultural land and maintain high soil fertility are presented - the priority is to close water and matter cycles through the incorporation of more natural vegetation cover into our landscapes and to restore the energy-dissipative properties of ecosystems.

Plant root and shoot dry weight, leaf relative water content (LRWC) and chlorophyll content were reduced by 30%, 21%, 15%, 34%, respectively, at 40mM NaCl as compared to non-salt stress conditions. However, membrane permeability (MP) of plant increased (85.0%) with increasing salinity. Foliar nutrient application (FNA) alleviated deleterious effects of salinity stress on growth and this effect was statistically significant. The highest alleviation effect of FNA at 40mM salinity stress was observed in the case of 10mM foliar KNO₃ and Ca(NO₃)₂ application, resulting in increase in plant root dry weight (50%), shoot dry weight (50%), LRWC (8.2%) and MP decrease (27.4%) at 40mM NaCl. Phosphorus, Fe and Zn contents in shoots and roots of plants also increased with FNA treatments, but they were still much lower than those of non-salt stress treatment. Sulphur, P, Fe and Zn contents of shoots reached similar values as in non-salt stress treatment when KNO₃ was applied, whereas Fe, Mn, Zn, and Cu contents of roots reached the values of non-salt stress treatment when Ca(NO₃)₂ was applied.

The heavy metal contents and their bioavailability were monitored in soils of Central Spiš region of SR. This area belongs to long term contaminated and hygienically loaded areas. Soil contamination by heavy metals is caused especially by ore mining, processing and treatment. Soil samples from the Central Spiš contained higher proportions of mobile forms which corresponded to the following sequence Pb > Zn > Cu, while for mobilizable forms the sequence of investigated metals was as follows: Cu > Zn > Pb. Soil pH is one of the parameters that affect significantly the share of bioavailable forms of metals. Higher proportions of mobile fractions of metals were detected in samples taken from soils with acidic pH. Statistical processing confirmed a relationship between the percentage share of lead and zinc in the mobile form and the level of pH/KCl, which was significant for Zn: r = -0.53. The relationships for lead and copper were insignificant.

The objective of this study was to evaluate the influence of organic (cattle manure) and inorganic fertilizers [composite NPK (15:15:15)] and natural zeolites on soil properties, vegetative growth and yield of apple plants grown on vertisol under Cacak conditions (Western Serbia). The results showed that the combined fertilization induced a decrease in acidity, an increase in humus content, a partial increase in total nitrogen (NTOT), and, primarily, a rise in available phosphorus (P) and potassium (K) levels. A highly significant (P < 0.01) interactive effect of the apple cultivars and nutrients on one-year-old shoot length and trunk cross-sectional area (TCSA) and a significant effect (P < 0.05) on yield per tree and yield per hectare were determined.

The investigation was carried out in 2005, on 30 plots chosen in the Central-Eastern part of the Emilia Romagna region, and cultivated with pear, grapevine and vegetable crops under the organic management system. For each crop, 5 plots with a level of calcium carbonate > 10% and 5 plots with a level of calcium carbonate < 3% were selected. For pear and vine, soil analyses were performed at the depths of 0-20 cm and 20-50 cm, for vegetable at the depth of 0-50 cm. Organic matter content was higher in pear-cultivated plots, followed by grapevine and vegetable crops. Copper application rate, from 1998 to 2004, was higher in pear and grapevine than in vegetable plots. Soil total and DTPA-extractable Cu were higher in pear and grapevine than in vegetable-cultivated plots. Soil DTPA-extractable Cu concentration was higher in the upper horizon than at 20-50 cm soil depth. The increase of total Cu in pear and vine-cultivated plots was combined with the increase of soil inactive Cu.

Sulfur (S) regarded as the fourth key element is mainly taken by the plant roots. However, some plants can also absorb atmospheric sulfides, which may be of great importance for ameliorating the environment and for farming as a green organic S fertilizer used to balance insufficient soil S content for intensive cultivation in China; H₂S and mainly SO₂ are emitted to air as a result of the rapid industrialized and economic development. Globe amaranth (Gomphrena globosa L.) might be one of the plants that can use atmospheric sulfides for its growth. Therefore the effects of sulfate deprivation from root on its growth, S status and other elements concentration under hydroponic culture were explored firstly. Based on measurements of plant growth, biomass, nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), S, iron (Fe), manganese (Mn), copper (Cu), zinc (Zn), boron (B), and molybdenum (Mo) concentration, the results showed that S concentration in flower, shoot and root of plant without root sulfate supplied was increased with plant growth and development, symptoms of S deficiency disappeared and other elements concentration in plant tended to be nearly the same as the root sulfate-supplied plants. The interesting results might imply that globe amaranth may be able to live on the atmospheric sulfides as sulfur source.