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The production of organic acids and changes during decomposition of rice straw amended with tricalcium phosphate (TCP) and Udaipur rock phosphate (URP) were studied under laboratory conditions. The organic C content of rice straw decreased and total N increased with time, resulting in a decrease in C:N ratio as the decomposition progressed. The pH decreased to acidic range in all the treatments on day 15, but became alkaline again later on. Soluble P increased at 15 days after incubation, declined later during decomposition, and was highest in the treatments containing TCP and Aspergillus awamori inoculation. Citric, oxalic, formic and maleic acids were detected during decomposition of rice straw and maximum amounts were present on day 15. Citric and oxalic acids were responsible mainly for P solubilization from TCP and URP; generally, citric acid was the most effective in P solubilization.

The effect of droplet spectra on efficiency of contact and systemic herbicides was evaluated. As a model components were used: mixture of clethodim 240 g/l + surfactant (90% raps fluid, 10% polyetoxyl esters); bentazon 600 g/l and bentazon 480 g/l + Wettol LF 150 g/l. The effect of droplet spectra on Elytrigia repens (L.) Desv. was evaluated using systemic herbicide (clethodim 240 g/l + surfactant). No significant differences of the efficiency were observed between different droplet sizes at the treatments of mixture of clethodim + adjuvant between very different droplet size ranging from VMD = 193 µm to VMD = 929 µm. The effect of droplet spectra on Chenopodium album L. and Galium aparine L. was evaluated using contact herbicides (bentazon 600 g/l and bentazon 480 g/l + Wettol LF 150 g/l). Six droplet spectra, ranging from VMD = 183 µm to VMD = 911 µm, were used. The efficiency significantly increased with smaller droplet sizes. The worst results were achieved by droplet spectra of 586 µm and 911 µm for both bentazon 600 g/l and bentazon 480 g/l + Wettol LF 150 g/l. Effect of droplet spectra is more pronounced in contact compounds. Translocation of systemic compounds may be the main mechanism that nullifies the effect of the droplets size and lower leaf coverage.

The portable soil core sampler was engineered for gradual sampling of soil profile in the depth up to 0.5 m, which ensures extraction of the whole sample volume of soil profile in determinable depth. The portable soil core sampler was compared with the professional soil probe Eijkelkamp P1.31 (Eijkelkamp Agrisearch Equipment, Netherlands) in field conditions. The portable sampler was compared with the physical soil sample rings in laboratory conditions to eliminate all of possible restrictive aspects affecting the procedure of measurement. The portable soil core sampler with inner diameter 71 mm, depth 120 mmenables gradually take samples of soil profile by step of 50 mmand is able to detect possible local extremes. On the other hand a soil probe is not able to reach desired accuracy in taking of a soil sample. Values measured from a soil probe approximately taken by step of 150 mmare inaccurate. The values of bulk density of both sampling methods were variable at significant interval from 40 into 80 kg/m³. Different values could be caused by soil profile condition and by the use of different sampling methods. The design of a portable soil sampler should be of assistance in fast and precise soil profiling sample collection, which is required to determine bulk density of the soil, its variance depending on moisture content in soil compaction determining criteria.

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.

The objective of this study was to examine and demonstrate how harvesting age (flower age) contribute to the variations in the quality of Echinacea purpurea (L.) Moench. The effects of different flower developmental stages on caffeic acid derivatives and isobutylamide content are described. These phytochemicals were extracted from fresh plants with 60% ethanol and quantified by the HPLC analysis. The results revealed that the quality of Echinacea is strongly influenced by the flower developmental stages. The highest content of both hydrophilic and lipophilic components in the anthodium of Echinacea plants were found in the third (mature) developmental stage, which is regarded as the optimum one for the harvest to obtain optimum yield levels.

This research was instigated by the fact that during the last decade annually repeated shallow disk tillage on the same field became frequent practice in Hungary. In order to study the changes of soil condition associated with disk tillage and to assess it is consequences, long-term tillage field experiments with different levels of nutrients were set up in 1991 (A) and in 1994 (B) on Chromic Luvisol at Gödöllö. The effects of disk tillage (D) and disk tillage combined with loosening (LD) on soil condition, on yield of maize and winter wheat, and on weed infestation were examined. The evaluation of soil condition measured by cone index and bulk density indicated that use of disking annually resulted in a dense soil layer below the disking depth (diskpan-compaction). It was found, that soil condition deteriorated by diskpan-compaction decreased the yield of maize significantly by 20 and 42% (w/w), and that of wheat by 13 and 15% (w/w) when compared to soils with no diskpan-compaction. Averaged over seven years, and three fertilizer levels, the cover % of the total, grass and perennial weeds on loosened soils were 73, 69 and 65% of soils contained diskpan-compaction.

Mercury (Hg) is one of the major pollutants in soils because of the annual import of toxic Hg into the agricultural lands. The aims of the present studies are to investigate the effect of Hg on chlorophyll content in winter wheat var. jinan No. 17. Moreover, calcium (Ca) levels and bioaccumulation of Hg in wheat leaves were studied with the technique of inductively coupled plasma sector field mass spectrometer (ICP-SF-MS). The study conducted a range of Hg concentrations from 0~500 mg Hg/kg in the dry weight soil. The soil was artificially contaminated with Hg as follows: 0, 100, 200, and 500 mg Hg/kg as HgCl₂. At early stages of the wheat growth, both low and high concentration of Hg stimulates chlorophyll content, but inhibits chlorophyll content at later stages of the wheat growth. Furthermore, the concentrations of Ca and Hg in wheat leaves increased with the increasing concentration of Hg on the thirty-fourth day with the technique of ICP-SF-MS. The results indicate that Hg can accelerate the absorption of Ca in winter wheat and Hg stress may affect Ca levels in wheat leaves.

The mixtures of Bromus marginatus Nees ex Steud. + Coronilla varia L., Festuca pratensis L. + Lotus corniculatus L., Dactylis aschersoniana Graebn. + Trifolium repens L., Arrhenatherum elatius (L.) P. Beauv. ex J.S. et K.B. Presl + Medicago lupulina L. were sown in rows of 125 mm in the year 1997 in Prague (chernozem, altitude 281 m a.s.l., average precipitation is 472 mm per year, average year temperature 9.3°C). The stands were one or three times per year cut with the mass removing or one or two times mulched. Botanical composition (by weight method), number of present species and agrobotanical groups (grasses, legumes, other dicotyledonous) coverage were measured during 6 years of vegetation. The species number was highest on plots cut 3 times (6-17), it increased linearly. The sown species share in the dry mass yield was 75-99% and the share of grasses decreased linearly with time. The significantly highest dry mass yield was reached when mulched two times per year Bromus marginatus Nees ex Steud. with Coronilla varia L. (till 14 t/ha ). The stands coverage was 43-80%.

Over 2004-2006, effects of mineral fertilisers (60 N + 30 P + 60 K kg/ha or 120 N + 30 P + 60 K kg/ha) and farmyard manure (12 or 24 t/ha) application on biological and chemical properties of soil were studied in seminatural grassland. The research trial was established at Radvaň site, central Slovakia (altitude 480 m, loamy to sandy-loamy Cambisol). These parameters were investigated during the growing seasons: CO₂ production, intensity of total N mineralisation (TMN), the rate of nitrification (NIT), total C content in microbial biomass (MB-C), C_ox, N_t, P, K, Mg and the humic acids to fulvic acids ratio (HA:FA). At the application of mineral fertilisers, the highest N rate significantly increased TMN and NIT, mainly in 2004 and 2005. The manure application showed the strongest effects on the biological parameters. The manure rate of 12 t/ha significantly increased the soil respiration in 2005 and 2006 as well as TMN and NIT throughout the research. The manure application increased also the soil pH, MB-C, N_t, Mg, P and C_ox.

Yacon [Smallanthus sonchifolius (Poepp. et Endl.) H. Robinson], a native plant of the Andes, belongs to the family Compositae (Asteraceae). It represents a traditional crop from the original population of Peru. Most of the tuberous root biomass is constituted by water (> 70% of the fresh weight). Saccharides, especially oligofructans, form 70-80% of their dry weight. Four yacon ecotypes originating from Bolivia, Ecuador, Germany and New Zealand were cultivated on the trial fields of the Czech University of Agriculture in Prague in 1995, 1996, 2000 and 2001. Considerable differences among the ecotypes were observed in their content of inulin (141-289 mg/kg d.m.) and lesser for fructose levels (195-217 mg/kg d.m.). No differences were found in glucose and saccharose contents. The highest inulin and fructose contents were found in the harvests from 2001 and 2000, similar trends were found for glucose. Statistically significant effect on the content of all saccharides has the year of cultivation. Tubers contained much higher levels of inulin (179 g/kg d.m.) and fructose (193 g/kg d.m.) in comparison with rhizomes. No significant differences were found for saccharose (higher in rhizomes) and glucose (lower in rhizomes). The contents of inulin and fructose in the upper and lower parts of tubers were reciprocal. During the storage period of 140 days at10°C and 75% a relative humidity inulin content decreased by 48.7% and monosaccharides content increased (fructose by 9.97%, glucose by 31.4%) due to hydrolysis. Likewise saccharose content increased by 12.9%.

Growth response of sugar beet plants to drought stress applied at different growth stages has been investigated. Cessation of watering imposed moderate water stress and resulted in the reduction of the relative water content of young and old leaves maximally by 6%. However, water content in taproot was more drastically decreased than in the shoot. Water withholding reduced dry matter accumulation and leaf assimilatory expansion when imposed at successive growth stages, especially in the case of earlier stress application. Substantial change in distribution pattern was observed when stress affected foliar development, more than 80% of dry matter was accumulated in the taproots. Water shortage negatively influenced both taproot and sugar yield by 16-52%, depending on the stress timing in the season. Drought stress did not change the sucrose concentration but when occurred in foliar and early stage of root development, decreased the contents of important non-sugar compounds like potassium and -amino-N solutes in the final yield. Overall, data concerning the different water status in particular organs implies that a hydrodynamic equilibrium does not exist within the sugar beet plant as a response to water stress. Drought imposed on the earlier stage, most drastically influenced plant growth and final yield. When water stress occurs at the end of crop cycle, sugar beet plants had a higher ability to recovery their growth.

Producers in highland and semiarid regions have difficulty in increasing diversity in crop rotations due to unfavorable conditions imposed by cool temperatures, inadequate rainfall, and shorter growing periods. In such conditions, safflower appears as a promising alternative because it is cold and drought tolerant. The objective of this study was to determine the responses of the hybrid and open-pollinated safflower genotypes to irrigated and non-irrigated conditions in a highland environment. For this reason, the field research was performed during the years of 2001 and 2002 in eastern Anatolia, Turkey. According to the results of the study, safflower genotypes tested were well adapted to the cool and short-season conditions in this region. The response of seed yield to genotype varied depending on the growing seasons. The non-irrigated plants produced nearly the same seed yield as irrigated ones. Average seed yields of safflower genotypes tested were 914.3 and 928.0 kg/ha in 2001, and 1143.6 and 1139.9 kg/ha in 2002 years for irrigated and non-irrigated experiments, respectively. In general, the genotypes differed in all of the investigated traits. In both irrigated and non-irrigated experiments genotype × year interactions were very significant for all parameters. This research shows that in semiarid and highland environments safflower has a big potential value as an oilseed crop under dryland conditions.

The influence of seed inoculation with a bio-preparation of nodule bacteria Rhizobium leguminosarum, fertilization of 0, 40, 80, 120 kg N/ha and molybdenum topdressing on the yield of green mass, dry matter, seed, average number of pods per plant, average number of seeds per pod, average nodule number per plant, nodule dry weight as well as plant and seed protein concentration were studied during the two years of investigations on two soils - Mollic Gleysols and Eutric Cambisols. The highest values of all investigated parameters were obtained in the inoculated seed variants with molybdenum application, except the average nodule number per plant where the highest values were achieved in variants without molybdenum. The effect of nitrogen fertilization depended on the soil type, i.e. its chemical properties. The largest number of the investigated parameters obtained the highest values as a result of fertilization with 40 kg N/ha on Mollic Gleysols (3.96% humus). Thus, seed yield was 4.02 t/ha, nodule dry matter 0.482 g per plant whereas seed protein concentration was 26.91%. The largest number of the investigated parameters on Eutric Cambisols (1.07% humus) obtained the highest values with fertilization of 80 kg N/ha where seed yield amounted to 3.65 t/ha, nodule dry matter 0.456 g per plant while seed protein concentration was 26.48%.

The paper deals with the possibilities of arsenic analysis in the soil. The aim is the selection and verification of the methods for analysis of As in the soil, which seem to be suitable for risk evaluation based on the increased As soil load. Economical and analytical availability of the methods is an important criterion. A sample set of 6 heavily contaminated soils was used to compare application potential of prevalent as well as less common procedures for determination of arsenic forms in soils. The results showed that substitution of analytically more demanding As total content analysis and sequential analysis for simple extraction using one-off agents seemed to be promising in many cases. The comparison and evaluation of statistical correlation of used methods of As analysis in the soil was realised. The results suggested that using the combination of simple 1M NH₄NO₃ extraction and determination procedure for amorphous Fe forms in the soil (the Tamm method) was suitable for the risk assessment stemming from the As contamination without necessity of the application of more complicated sequential extraction procedures.

Formerly arable luvic chernozem set aside for ten years (1997-2006) with different herbaceous cover (grass, legumes and their mixtures) and agronomical practices (mulching and cut/harvesting) was studied. The experimental plot was maintained as black, spontaneous and controlled fallows from 1997 until July 2003 (BD period). In July 2003 the plots were desiccated by glyphosate herbicide and were run as a black fallow until August 2004 (AD). The last period (AG) was characterized by monoculture of Italian ryegrass cut/harvested twice a year until October 2006. The experimental soils were characterized with 18 parameters. Mulched plots in all periods (BD, AD and AG) were evaluated as highly microbial active plots. The black fallow (BD) permanently maintained by glyphosate herbicide was the lowest in biological parameters. The desiccation caused a highly significant increase (P < 0.01) of nitrates in topsoil, but in following period (AG) their significant decrease was detected. Desiccation enhanced carbon immobilization into microbial cells especially on mulched and cut/harvested sites (BD, AD). Due to mulching accumulation of soil organic matter highly significantly increased (P < 0.01). This induced a highly significant (P < 0.01) increase in the basal respiration (AD, AG) as the soil organic matter accumulated in the period BD was intensively mineralized.

In order to study the characteristics of element values in the cell of plants and soils and their relationships that would help to evaluate the biogeochemical effect of soil on the element contents in the cells of plants in the same environment of Southwestern China, the soil samples were collected for analysis and the weight and atom percentage of elements (WT% and AT%) in the leaves of two different species of Flos Lonicerae were analyzed by the electron probe (EDX-9100). The results of soil analysis show that the nutrient element contents in the soil are determined by the liable content of elements, which were arranged as: Ca > Mg > Cu > Mn > K > Na > P > B > SiO₂ > Zn > Fe, even though the total element values in soil of different horizons were arranged as: SiO₂ > Fe > Ca > Mg > K > Na > Mn > P > Zn > B > Cu. It indicates that karst environment is composed of soluble calcium-rich rock and soil scarcity. Moreover, the migratory velocity and availability of elements are also determined by their coefficient variability. According to statistical results, Ca, Mn and P in the soil have high coefficient variability, reflecting its background of karst soil. Based on the electron probe, it is shown that the content of Ca is higher while Mg is the lowest in the cell of two different species of Flos Lonicerae (r = -0.156, P < 0.05) and the content of P in the cell is inferior to Ca (r = 0.868, P < 0.01). By studying the relationship of soil and the plants, it can be seen that these results are probably caused by the characteristics of local biogeochemistry. Ca is mainly absorbed by plant with the help of transpiration and accumulated in the cell, and thus becomes a predominant element in the cell. The accumulation of Ca in cell of plant will affect the absorbency and the content of other elements in the cell of Flos Lonicerae, resulting in the different contents of other elements in the Flos Lonicerae through synergistic and antagonistic action, followed by the affected quality and officinal value of the Flos Lonicerae.

Urbanization has drastically changed soil properties, and an assessment of these changes is essential for soil management and soil health. The activities of urease, acid phosphatase, invertase and catalase, soil organic matter, pH, electrical conductivity (EC) and clay (< 0.01 mm) content of urban soils under two land-uses in the central built-up area of the Shenzhen city were investigated, and multivariate analysis was used to study the relationship between soil enzymes and soil physical-chemical properties. The results showed that invertase activity in roadside soil was significantly higher than that in urban park soil, whereas catalase activity was significantly higher in urban park soil. Soil organic matter had significant positive correlation with activities of invertase, urease and acid phosphatase but not with catalase. Soil pH had a significant negative direct effect on urease and acid phosphatase activity, but the effect was counteracted by positive indirect effect of soil organic matter. Soil EC had a positive direct effect on activities of catalase and there was a significant correlation between soil EC and soil catalase activities. Soil organic matter, soil pH and EC were the major factors influencing activities of soil enzymes.

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.

By reference to the Eternal Rye trial in Halle, Germany, as an example, it is demonstrated that long-term trials provide indispensable information for contemporary and future land use research. These trials serve as tools for the examination of cultivation measures or the effects of climate on nutrient dynamics and mobilization, microbial biodiversity, mineral composition or soil formation processes. They are therefore essential for the evaluation of land-use strategies or climatic change and, because of that, can provide more accuracy in related political considerations.

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.

Basmati rice (Oryza sativa L.) cultivars viz. PRH-10 (pusa rice hybrid-10) and PS-2 (Pusa Sugandh-2) were grown under two different day/night temperatures (31/24°C, 35/28°C) at ambient (370 μmol/mol) and elevated (550 μmol/mol) carbon dioxide (CO₂) concentration, respectively, to characterize how an increase in CO₂ and temperature affects rice photosynthesis and carbohydrate metabolism. At elevated CO₂, the photosynthetic rates increased under both the temperature regimes, compared with plants grown at ambient CO₂. The photosynthetic rate, sucrose-P synthase (SPS) activity and accumulation of soluble sugars and starch were higher in PRH-10 (pusa rice hybrid-10), compared to PS-2 (Pusa Sugandh-2). Elevated temperature decreased the photosynthetic rates both under ambient and elevated CO₂ conditions. The SPS (sucrose-P synthase) activity and the accumulation of soluble sugars and starch were enhanced at elevated CO₂ under both temperature regimes compared with plants grown at ambient CO₂. The up-regulation of SPS (sucrose-P synthase) under elevated CO₂ and temperature would be beneficial for growth and productivity of rice plants for the future climatic conditions.

A gradual increase of phosphorus (P) concentrations in combination with organic and mineral fertilizers was applied to clayey soils at six precise experimental field sites with different climatic conditions within the Czech Republic. Soil samples were collected after the harvest of barley. Readily available P concentrations were determined using water and 0.01M CaCl₂ extractions, mobile phosphate contents were determined using the extraction procedures Mehlich 3 and Olsen. Furthermore, P uptake by barley plants was assessed. All selected procedures showed that increasing concentrations of applied P increased the mobile and readily available P contents in soils. Phosphorus uptake by barley plants ranged between 9.00 and 14.5 kg/ha and increased P application resulted in increased P concentrations in plants. Statistical analyses were performed using the Spearman test. The closest relationship was obtained for P uptake by plants and the water extraction (r = 0.81). Significant relationships were also obtained for plant uptake and the Mehlich 3 and CaCl₂ methods (r = 0.40 and 0.36, respectively). There was no statistical dependence between P uptake and the Olsen method (r = 0.25). Regression analysis was expressed best as linear regression. The closest relationship was found for water extracts and P uptake by plants (with a determination coefficient of 65%). Determination coefficients for P uptake and other methods used were significantly lower (max. 20%).

The fertilising experiment was set up in 1968 on the mountain meadow (720 m a.s.l.) in Czarny Potok near Krynica (20°8' E, 49°4' N). The experiment was conducted on the acid Cambi soil and comprised objects fertilised with two nitrogen forms and two doses against the background of PK fertilisation, the untreated object, and plots with unilateral P and N fertilisation. The paper concerns 30 years of investigations (1968-1997) of the effect of different NPK fertilisation on the dynamic of yields and the meadow sward quality against a background of the same treatments. The dynamic of the botanical composition was presented as well as the dynamic of the grassland yield potential with systematic mineral fertilisation and liming. The application of nitrogen fertilisation with the rate of 90 N.ha^-1 + PK under mountain conditions and systematic liming of the meadow enables to maintain or increase production over the long period, to decrease the production risk and to prevent degradation of the environment and natural resources.

Most of the works published since the beginning of the 20^th century have brought interesting results about beneficial effects of titanium (Ti) on plants, but much less is known about its phytotoxic effects at higher doses. Here we demonstrate the influence of Mg treatment on the phytotoxic effects of Ti. Mg, Ti + Mg and two different concentrations of Ti leaf sprays were applied on oats (Avena sativa L. cv. Zlaťák) grown on three different soil types (Fluvisol, Luvisol and Chernozem). Physiological parameters of oats as well as some essential elements contents were analyzed. The foliar applications of Ti caused significant toxic manifestations on oats at ≥ 10 mg/kg concentrations. Mg partially ammeliorates these toxic effects if applied together with Ti. The effect was strong on Fluvisol, but weaker on Chernozem and Luvisol. Ti effects are more significant the further the soil is from the nutritional optimum of the plants. This is most evident in the case of Fluvisol, which is deficient in Mg, Fe, Mn, and Zn. It seems that Ti possesses a generally equalizing effect on the elements content in the plant.

Microbial biomass and community catabolic diversities at three depths (0-10 cm, 20-30 cm, and 40-50 cm) in Chinese Mollisols as influenced by long-term managements of natural restoration, cropping and bare fallow were investigated. Microbial biomass was estimated from chloroform fumigation-extraction and substrate-induced respiration (SIR), and catabolic diversity was determined by using Biolog® EcoPlate. Experimental results showed that microbial biomass significantly declined with soil depth in the treatments of restoration and cropping, and not in the treatment of bare fallow, where the microbial biomass had a positive relationship with the total soil C content. The inspections into the catabolic capability of the microbial community at the same soil depth showed that the treatment of natural restoration had a relatively stronger metabolic ability than the cropping and bare fallow treatments. Shannon"s diversity index, substrate richness and substrate evenness calculated from the Biolog data were higher in the treatments of natural restoration and cropping than the bare fallow treatment with the same soil depth, and with the highest values in the top soil. Principal component analysis indicated that the catabolic profiles not only varied with the soil depth in each treatment, but also differed in the three treatments within the same soil depth. The catabolic profiles of the three treatments were similar to each other in the soil depth of 0-10 cm and distinctly different in the soil depths of 20-30 cm and 40-50 cm. These results suggest that it was microbial biomass rather than community function that was influenced by the different soil management in the topsoil (0-10 cm); in the relative depths, the soil microbial community function was more easily influenced than microbial biomass.

In the years 2004 and 2005 precise field trials were performed with the aim to evaluate the effect of variety, year of cultivation, N, P, K and Mg fertilization, and the cover with white propylene fibre Paegas-Agro UV 17 on the total carotenoid content (TC) in potato tubers. TC was determined by absorption UV-VIS spectrophotometry and obtained results were statistically evaluated (ANOVA and MANOVA variance analyses, Scheffe's test). Statistically significant differences (P = 0.05) in the ability of varieties to synthesize carotenoids were found (Karin, Agria and Marabel with high TC × Impala and Saturna with low TC) and also the year of cultivation significantly affected TC (5.8 mg/kg fw in 2004, 20.9 mg/kg fw in 2005). The effect of fertilization with N, P, K and Mg on TC in potatoes did not show any significant effect; however significant differences were observed among varieties. The effect of white polypropylene fibre in two early potato varieties (Adora and Impala) during three dates of harvest on TC in potato tubers was not significant. Contrariwise, statistically significant effects on TC were reported in the case of potato tubers maturity, year of cultivation and potato variety.

European winter wheat landraces and obsolete cultivars (121 accessions in set I and 101 accessions in set II) with modern check cultivars were evaluated in three-year field trials. Increased spike productivity in modern cultivars could be attributed mainly to increased number of grains in spikelet and increased HI, whereas TGW has marginal effect. Old cultivars had on average by 2-3% higher crude protein content in grain than modern ones. Among selected 10 characters, relatively wide diversity (C.V. 11-20%) has been estimated in spike length and characters of spike productivity (except of grain weight with C.V. close to 9%). It was difficult to distinguish the cultivars according to the country of origin, however, earliness and lower spike productivity seems to be characteristic for South-East origin whereas cultivars from North-West Europe showed opposite characters. Correlation analyses showed close relations between earliness in heading and in maturity and negative relation between late heading and grain filling period, which was positively correlated with TGW and HI (r = 0.26 to 0.38). Number of grains in spikelets was highly correlated with spike productivity and HI (r = 0.62 to 0.69) whereas relations between these two characters and TGW were lower (r = 0.20 to 0.51). Spike productivity characters, except of TGW, are in negative correlation with crude protein content in grain (r = -0.34 to -0.50). Regression analyses confirmed that main determining character for the spike productivity is number of kernels in spikelet (about 40% of variation) while effects of TGW are about half-size. Crude protein content was positively affected by plant height (15-30% of variation) impact of grain weight per spike was lower (14-17% of variation) and negative. Potentially valuable donors of earliness and longer grain filling period were identified for further studies and/or utilization in breeding programs. As especially valuable character can be considered very high crude protein content (around 18% in cvs Berg-land, Ukrajinka, Sippbachzeller, Innichen Nr. 25001 and Barbu du Finistre). High crude protein content combined with relatively good spike productivity and/or long grain filling period or earliness was found in cvs Visperterminen 640 E, Hatvan, Szekacz 1242, Berchtesgardener Vogel, Ble du Lot and Barbu du Finistere.

There are evidences of beneficial effects of selenium (Se) on plant growth. In this work, using alfalfa (Medicago sativa L.) and two varieties of Brassica oleracea L. (cabbage and kohlrabi), the effect of Se addition (10 and 20μM) on growth and concentration of sulfur and Se was investigated in hydroponic experiments. In order to study the involvement of Se-mediated changes in the antioxidant capacity of plants in growth promotion by Se, the activity of antioxidant enzymes including ascorbate peroxidase (APX), catalase (CAT), peroxidase (POD), superoxide dismutase (SOD) and glutathione reductase (GR) and the concentration of H₂O₂ and glutathione were determined. It was demonstrated that sulfur sufficient cabbage and kohlrabi plants concomitant with growth stimulation in response to Se addition expressed a progressive oxidative stress as judged by a lower activity of antioxidant enzymes and accumulation of oxidants. Results imply that the function of antioxidant system of plants could not explain either the growth stimulatory effect of Se in cabbage and kohlrabi or different response of alfalfa plants to Se supplementation.

Yacon [Smallanthus sonchifolia (Poepp. et Endl.) H. Robinson], a native plant of the Andes, belongs to the family Compositae (Asteraceae) and it represents a traditional crop of the original population of Peru used in traditional medicine. A major portion of tuberous root biomass is composed of water (> 70% of fresh weight). Saccharides, especially oligo-fructans, form 70-80% of dry weight, protein content ranges between 0.3% and 3.7%. Fructooligosaccharides of inulin type b (2®1), mainly oligomers (GF2-GF16), are known for their ability to keep the colon healthy. Yacon sweetness is predominantly caused by fructose, which is by some 70% sweeter than sucrose. Other oligosaccharides are 1-kestose and nystose. Diabetics and persons suffering from digestive problems are recommended to consume yacon because its sugars are not available from the small intestine. The mean tuberous root composition per 100 g of fresh matter is 81.3, 13.8, 0.9, 1.0, 0.1 and 1.1 g of water, saccharides, fibre, proteins, lipids and ash, respectively. Mean mineral contents per 100 g of fresh matter are 334, 34, 12, 8.4, 0.4 and 0.2 mg of potassium, phosphorus, calcium, magnesium, sodium and iron, respectively. Vitamins B1, B2, C, b-carotene and polyphenols in the same weight are present at mean concentrations 0.07, 0.31, 5.0, 0.13 and 203 mg, respectively. Yacon can be considered an industrial crop, particularly as a source of inulin. The used forms are flour, syrup, extract from tuberous roots and moreover leaf extract for the preparation of yacon infusion with hypoglycaemic effect. In yacon leaves di- and sesquiterpenes with protective effects against insects are present, among them mainly ent-kaurenic acid (ent-kaur-16-en-19-oic acid) and its derivative - 15-a-angeloyloxy-ent-kauren-19-oic acid 16-epoxide. Other components are polyphenolic antioxidants, esp. hydroxycinnamic acids and chlorogenic acid. A new antifungal melampolide - sesquiterpene lactone named sonchifolin, as well as three known melampolides, polymatin B, uvedalin and enhydrin, were isolated from leaf extracts of yacon. Three major phytoalexins were isolated: 4'-hydroxy-3'-(3-methylbutanoyl)acetophenone, 4'-hydroxy-3'-(3-methyl-2-butenyl)acetophenone and 5-acetyl-2-(1-hydroxy-1-methylethyl)benzofuran.