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The aeroponic system is a viable technological alternative for potato minituber production within a potato tuber seed system. The aim of the study was to evaluate the productivity of potato minitubers grown in aeroponic culture and collected in 14 successive periods of the growing season. The minitubers of cvs. Ametyst and Tajfun were tested in an experimental field after a storage period. It was found that cv. Ametyst was characterized by higher yield and number of tubers than cv. Tajfun. Yield of cv. Ametyst averaged 42.6 t/ha, and cv. Tajfun 37.3 t/ha. The number of tubers over 3 cm of cv. Ametyst averaged 644.2 per ha, and cv. Tajfun 437.7 per ha. The yield and number of tubers was dependent on the physiological age of minitubers harvested on successive dates. Comparing the productivity of minitubers grown in aeroponics and in the soil, a significant difference was found in the number of tubers with a transversal diameter over 3 cm. There were more daughter tubers from minitubers grown in soil. They are the result of different-size minitubers used for planting, smaller ones from aeroponics and larger from soil.

In the present study, the effects of fungicide Aliette WG 800 [80% fosetyl-Al (aluminium tris-o-ethyl phosphonate)], widely used against Phytophtora infestans on tomatoes grown in greenhouse in Turkey, were studied on the morphology and viability of tomato (Lycopersicon esculentum Mill.) pollens. The fungicide was applied to tomatoes grown in greenhouse at recommended dosage (200 g/100 l water) and at double the recommended dosage (400 g/100 l water). The fungicide caused changes in the morphological structures of tomato pollens. Some pollen morphological structures that are not observed in the control group were encountered in the pollens in equatorial view and in polar view at 200 g/100 l treated groups. On the other hand, pollen viability level decreased as the dosage increased. Especially, non-viable pollen types such as wrinkled pollen or pollen with abnormal shape were encountered in the fungicide groups. It was expected that the pollen fertility as well as yield would decrease in future.

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

The objective of the present study was to evaluate the effect of P, Ca, S, and/or K and/or Mg application at different rates on the botanical composition, herbage yield and its nutritive value in dehesas developed on calcareous soils. In two growing seasons, 2009/10 and 2010/11, five surface-broadcast fertiliser treatments were applied once in autumn. Two grazing periods were simulated by cutting the pasture in mid-spring and late-spring. Treatment K1, with the highest amount of Ca and without K in its composition, provided higher crude protein values in the herbage than controls in 2009/10. When the effect of each nutrient was analysed separately, a strong and highly positive response of Mg application on herbage production was recorded. A surface application of fertilisers containing 25 kg Mg/ha in autumn could increase herbage yield by 40% under the studied conditions. However, Mg was not applied alone, and thus this increase could be due to an effect of Mg by itself or to a synergistic effect between Mg and other nutrients applied. The application of Ca, P and Mg may also favour the production of high-quality forage by yielding a greater cover of legumes and digestible protein.

Humic acid urea fertilizer (HA-N) is a new type of slow-release nitrogenous fertilizer that can enhance utilization rate of urea, and consequently increases crop yield. However, there were few researches about the effect of HA-N on the nitrogen absorption and utilization in sweet potato production. Hence, the effect of HA-N on nitrogen accumulation and distribution, nitrogen use efficiency (NUE), and yield of sweet potato was studied in the field using the ¹⁵N tracer technique. Results showed that HA-N significantly increased the number of storage roots per plant and the average fresh weight per storage root, as well as the yield increased by 29.6% compared with urea fertilizer. Furthermore, nitrogen accumulation of total plant was higher under the HA-N. In addition, HA-N significantly increased nitrogen production efficiency of fertilizer and nitrogen production efficiency. Results of a ¹⁵N tracer experiment revealed that the percentage of nitrogen absorbed by plant from fertilizer increased from 31.1% to 38.7% and NUE increased from 33.5% to 44.8% with application of HA-N when compared with single N treatment, respectively. HA-N significantly increased sweet potato storage root yield, nitrogen absorption and NUE, as well as it reduced the loss of nitrogen fertilizer.

Dissolved organic nitrogen (DON) has high bioavailability and is an important source of soil nutrients. In order to determine the concentrations and the composition of DON in different depths (0-30 cm), and provide a theoretical basis for further deep research into the paddy soil nitrogen supply, experiments based on the lysimeter method were carried out to investigate the effect of fertilization on composition and spatial distribution of DON in paddy soil. Paddy soil was treated under chemical fertilization treatment (CT) and mixed fertilization treatment (MT). With methods of PCR-DGGE and HPLC-MS, the results of the experiments suggested that the samples in 10-20 cm and 20-30 cm under MT had significantly higher bacterial diversity than those under CT except in 0-10 cm. DON had a high percentage (63.1-79.9%) in N_tot of soil solution. The results of the correlation analysis revealed that DON had a significant positive correlation with organic matter content, Shannon-Wiener diversity index (H') and a significant negative correlation with pH. The possible results of HPLC-MS identification of DON from paddy soil solution were that (a) 3-(4-thiazolyl)-l-alanine; (b) 2-phenylbenzimidazole-5-sulfonic acid; (c) 4-(2, 4-difluorophenyl)-3-nitrobenzene carbaldehyde; (d) fendizoic acid.

Wheat grain products are the primary source of dietary Cd-intake for humans. Since varieties differ markedly in grain-Cd accumulation, efforts are needed to find traits associated with low, or high, accumulation. Two durum wheat varieties, selected in a field screening as low (Creso) and high (Svevo) grain-Cd accumulating, were grown on soil spiked with 1.5, 3 and 4.5 mg Cd/kg. Growth patterns, Cd uptake and translocation were investigated at heading and maturity. Cadmium did not affect plant growth and grain yield, but grain-Cd concentration always exceeded the permissible limit of 0.2 mg Cd/kg, and was approximately double in Svevo than in Creso. At maturity, total Cd-uptake increased linearly with supply in Creso, from 13 to 23 µg/plant, and was approximately 18 µg/plant, irrespective of Cd level, in Svevo. Partitioning to shoot was higher in Svevo than in Creso, both at heading and maturity. We suggest that reduced plant height, high root to shoot biomass ratio during vegetative growth and elevated post-heading dry matter accumulation promoted Cd accumulation into grain. Since these traits are common to modern wheat varieties, risks of grain Cd-contamination can increase in the future.

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.

Problems concerning total dry weight and distribution of underground phytomass were studied in a pasture trial at Rapotin near Šumperk, the CzechRepublicin the period 1995-1999. The total weight of dry underground pasture phytomass (DUP) was 976 g/m² (5-year average) in a soil layer of 0-200 mm (both live and dead roots). The DUP was significantly increased by mineral fertilizers (90 kg N/ha, 30 kg P/ha a 90 kg K/ha). The weight of DUP was not significantly influenced by a grazing system, renewal or resowing of the original grassland. In unfertilized plots, DUP weight amounted to 989 g/m², i.e. 92 g/m² (8.6%) less than in fertilized plots in the period 1996-1999. In the same period, under the grassland exploited by rotational grazing 1142 and under continuous grazing 1082 g/m² DUP were determined, i.e. by 60 g/m² (5.5%) less. The highest DUP weight in the period 1996-1999 was found in autumn 1997 (1222 g/m2) immediately before achieving the maximum forage yield in May 1998. In a layer of 0-20 mm, 54.6% of the total DUP was found. In this surface layer, significant increase in the DUP weight was found in fertilized plots. In 1999, some 88.5 and 90.2% of DUP were concentrated in unfertilized (903 g/m²) and fertilized (952 g/m²) plots, respectively in a layer of 0-100 mm.

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.

Three-year trials were conducted to study germination and emergence of prickly lettuce (Lactuca serriola L.) achenes, increments of shoot dry matter and susceptibility of the weed to selected herbicides. The germination rates of achenes at10°C (92%),20°C (97%) and30°C (95%) did not indicate any significant differences within 20 days from sowing. The highest percentage emergence of prickly lettuce achenes was determined after their sowing into a depth of1 mm. Differences from the variants of sowing onto the soil surface (0 mm), into a depth of 10 and20 mm were significant. There were no differences in the emergence rates from a depth of 10 and20 mm. The highest increments of shoot dry matter were observed when prickly lettuce plants were grown for 4-7 weeks after sowing at20°C. The effect of selected herbicides on prickly lettuce plants treated at the stage of 2-3 true leaves was evaluated on the basis of a change in the content of shoot dry matter. A significant decrease in dry matter against the control was recorded in all variants after herbicide application. The effect (expressed by a lower dry matter content) was significantly higher after the combination amidosulfuron + iodosulfuron-methyl + mefenpyr-diethyl (10 + 2.5 + 25 g/ha) was used than after the application of tribenuron (10.85 g/ha) and picolinafen + cyanazine (120 g + 480 h). The effect of amidosulfuron (22.5 g/ha) was significantly higher than in the variants treated with tribenuron, picloram + clopyralid (16.75 + 66.75 g/ha), clopyralid (90 g/ha) and picolinafen + cyanazine (150 + 600 g/ha). The best effects were produced by herbicides containing amidosulfuron and iodosulfuron as active ingredients.

Around half of the cereal growing soil in the world are zinc (Zn)-deficient and it severally affects the health of plants, animals and humans. In order to investigate the enrichment of Zn in cereals a pot experiment was conducted in two contrasting wheat genotypes viz., UP2628 (Zn efficient) and UP262 (Zn inefficient) under different methods of Zn application such as control (0 Zn), soil application (5 mg Zn/kg soil tagged with 3.7 MBq of ⁶⁵Zn/pot), foliar spray of 0.5% ZnSO₄ at 30, 60 and 90 days (tagged with 925 KBq of ⁶⁵Zn/pot), soil application (5 mg Zn/kg soil tagged with 3.7 MBq of ⁶⁵Zn/pot) + foliar spray of 0.5% ZnSO₄ at 30, 60 and 90 days (tagged with 925 KBq of ⁶⁵Zn/pot). Cultivars showed marked difference in ⁶⁵Zn accumulation and grain Zn content. In both contrasting genotypes the highest Zn content in grains was recorded under soil application + foliar spray of Zn fertilizers. Both UP262 and UP2628 showed similar accumulation of ⁶⁵Zn in leaves however, UP2628 exhibited better translocation efficiency and accumulated higher ⁶⁵Zn in stem and grains than UP262.

An experiment was conducted to study the effect of heavy metals (Cd, Cr and Pb), soil texture (sandy, loam and clay) and incubation periods (7, 15, 30, 60, 90 and 120 days) on soil respiration (CO₂ evolution) during sugarcane trash decomposition in laboratory conditions of the Indian Institute of Sugarcane Research, Lucknow, India. Surface soils (0-15 cm) were collected from agricultural fields and crop residue of sugarcane trash (Saccharum officinarum L.) was taken in the institute farm. Crop residue (10 t/ha) and heavy metals (10, 50, 100, 1000 μg/g) were mixed and incubated at 30°C ± 2°C in an incubator. The rate of soil respiration (CO₂ evolution) decreased with increasing heavy metals concentration. During the 120 days, the toxicity decreased but still remained significant. Maximum soil respiration was recorded at 7 days of incubation period; further, it decreased with increasing incubation period. The highest drop of soil respiration rate was caused by addition of 1000 μg/g Cd, Cr and Pb levels. Clay soils evolved maximum CO₂ followed by loam and sandy soil.

Changes of amino acid (AAs) contents (glutamic acid - Glu, aspartic acid - Asp) and fatty acids profile (FAs) in spinach under cadmium (Cd) soil contamination (Cd1 = 30, Cd2 = 60, Cd3 = 90 mg/kg soil) are reported here. Spinach plants were sampled 25, 40, 55 and 75 days after sowing. Growing Cd soil contamination was associated with the strong inhibition of above-ground biomass (23.5-6.3 g dry matter per pot) and with the enhancement of Cd content (0.60-72.38 mg/kg dry matter) in leaves. During 55 days of plant growing the increase of Glu and Asp content was associated with the enhancement of Cd content. The highest accumulation of AAs was determined on Cd3 treatment after 55 days of cultivation. Strong decreases of both AAs were confirmed in the last sampling period for Cd treatments (reduction of Glu content of Cd3 treatment to ca. 64% and Asp content to ca. 72% in contrast to control). The content of saturated fatty acids increased (mainly palmitic acid) and the content of unsaturated fatty acids decreased in spinach aboveground biomass with increasing Cd concentration. Results of multivariate analysis of variance MANOVA showed the significant effect of Cd contamination for FAs metabolism, but the most significant effect was confirmed for plant growing period.

Three non-food cultivars of winter wheat (Biscay, Clarus, Rapsodia) were grown at four locations in the Czech Republic with different agro-ecological conditions in the years 2005-2008 and two levels of nitrogen fertilization - 90 and 120 kg N/ha were used. The influence of growing conditions (year, location, cultivation technology) on grain yield, starch content, protein, gluten, share of amylose in starch, falling number and amylographic characteristics. All qualitative indicators were significantly affected by the weather. Wheat grown in the areas 500 m a.s.l. had lower grain yield of 2.8 t/ha (8.4 t/ha), higher starch content of 2.1% (69.0%) and lower content of proteins by 1.8% (10.2%) in grain than wheat grown in the fertile conditions (below 300 m a.s.l.). The cv. Biscay had the highest starch content of 68%; the proportion of amylose in the starch was in the range 22-27%. The content of proteins was negatively correlated with starch content (r = -0.89). The level of damage of starch α-amylase was most affected by wet weather during ripening - falling number was 62 s, with a very low amylographic gelatinization maximum(30-155 Brabender units) and a low gelatinization temperature at the maximum (67-74°C). The respective values recorded in dry conditions were ca 300 s, AU 600 and 90°C. Most damaged starch was recorded in the cv. Clarus.

This study was conducted to determine the effect of row spacing (40, 60 and 80 cm) on forage dry matter (DM) yield and quality of four hybrids grown in the years 2001 and 2002. The highest DM yield was obtained from the Arifiye (24.1 and 22.4 t/ha) while the lowest DM yield was obtained from Pioneer 3163 (19.9 and 19.8 t/ha) in the years 2001 and 2002, respectively. As row spacing increased, DM yield as an average of two years decreased from 27.2 to 16.6 t/ha. No differences were found among row spacing for DM content, harvest index (HI) and ear content. As row spacing increased, whole-plant acid detergent fiber (ADF) and neutral detergent fiber (NDF) content increased from 214 to 227 g/kg and from 420 to 451 g/kg during the year 2001, respectively. However, ADF content decreased from 281 to 267 g/kg and NDF contents decreased from 530 to 515 g/kg with increasing row spacing during the year 2002. In this study, hybrids showed distinct differences for crude protein, ADF and NDF contents in both years. Forage quality parameter including ADF and NDF of Pioneer 3163, TTM 8119 and Karadeniz Yildizi were higher than Arifiye hybrid.

A reduction in the water available to plants will lend increasing importance to the dynamics of water uptake and to the water use efficiency (WUE) of cereals. The effect of drought on the water use efficiency of winter cereals was investigated in a greenhouse experiment in the Centre for Agricultural Research. The effect of water deficiency on the water use properties was studied by measuring changes in the grain weight, thousand-kernel weight and aboveground biomass. The water use efficiency of wheat varieties generally ranged from 1.5-2.3 kg/m³ and 1.06-2.0 kg/m³ in the case of optimum and limited water supplies, respectively, while these figures were 1.4 kg/m³ and 0.8 kg/m³ for winter barley and 0.8 kg/m³ and 0.5 kg/m³ for winter oat. Investigation on the relationship between harvest index (HI) and WUE was found that the harvest index is only one indicator of drought tolerance; but the stability of HI under non-optimum environmental conditions also needs to be determined.

Subsoil compaction can result in unfavourable soil physical conditions and hinder the root growth of maize. The effects of deep tillage and conventional tillage on soil physical properties and root growth of maize were studied during 2010-2011 at two sites (loam at Hebi and clay at Luohe) in central China. The results showed that soil penetration resistance, bulk density, water content and root length density were significantly affected by tillage, soil depth and year. Deep tillage had lower penetration resistance and lower soil bulk density, but higher soil water content than conventional tillage across years and depths. Averaged over the whole soil profile, deep tillage not only significantly decreased penetration resistance and soil bulk density, but significantly increased soil water content and root length density on loam, while deep tillage only significantly increased the root length density on clay. We conclude that deep tillage on the loam is more suitable for the root growth of summer maize.

The aim of the study was to collect seeds of wild oat from the fields where, in spite of the applied herbicides, the weed is very poorly controlled, and to determine under greenhouse conditions if any resistant biotypes are present. In the years 2008-2011, 34 samples of wild oat were collected from fields where the weed was poorly controlled. The biotypes were analyzed in greenhouse experiments to determine if they are resistant to herbicides. Among five resistant biotypes three of them (R3, R4 and R5) were resistant only to iodosulfuron and mesosulfuron, and biotype R2 - only to propoxycarbazone-sodium. Biotype R1 exhibited multiple resistance to iodosulfuron + mesosulfuron and pinoxaden. The use of sulfometuron proves that the mechanism of resistance of two biotypes of wild oat (R1 and R4) to acetolactate synthase inhibitors is associated with target-site mutation. The curve of biotypes R3 and R5 controlled with iodosulfuron + mesosulfuron shows a relatively low resistance index and control of those biotypes with sulfometuron indicates a metabolic resistance.

To assess the effects of long-term fertilization on soil available micronutrients in farmland, this study examined diethylenetriaminepentaacetic acid (DTPA) extractable iron (Fe), manganese (Mn), copper (Cu), and zinc (Zn) in surface soil with monoculture of corn (Zea mays L.) with a 30-year filed fertilization experiment established in Northeast China. Treatments included no fertilization (CK); nitrogen only (N); nitrogen and phosphorus only (NP); NP and potassium (NPK); NPK plus cornstalk (SNPK), and NPK plus farmyard manure (MNPK). Results showed that DTPA-Fe and Mn were significantly increased with chemical N application, and DTPA-Cu and Zn were significantly increased with farmyard manure amendment, while micronutrients were not significantly different between treatment SNPK and CK. DTPA-Fe and Mn were about twice to threefold in treatments N, NP, and NPK as much as in treatments SNPK, MNPK and CK. DTPA-Cu and Zn in treatment MNPK were about 3.9 and 6.5 times as much as in CK. DTPA-Fe and Mn decreased with the increasing of soil pH and cation exchange capacity, while DTPA-Cu and Zn increased with the increase of soil organic carbon and electrical conductivity.

Chicory (Cichorium intybus L.) is a rich source of polysaccharides (intibin and inulin), vitamins, acids and mineral salts. The present studies determined the antagonistic activity of selected bacteria of the soil environment of root chicory towards fungi pathogenic towards this plant: Alternaria alternata, Botrytis cinerea, Fusarium culmorum, F. oxysporum, Thanatephorus cucumeris and Sclerotinia sclerotiorum. Root chicory was cultivated with using cover crops (oats, tansy phacelia and common vetch). The use of cover crops, especially oats, in the cultivation of root chicory had a positive effect both on the total population of bacteria and the population of Bacillus spp. and Pseudomonas spp. in the soil. Antagonistic Bacillus spp. and Pseudomonas spp. displayed differentiated activity towards the studied fungi. The greatest antagonistic effect was found out after the mulch of oats. After common vetch, the antagonistic activity of bacteria was more than twice, and after phacelia three times as low as after oats. In the traditional cultivation of root chicory this activity was nearly twelve times lower.

A litterbag experiment was conducted to investigate the changes of tannins and nutrients in branchlets at different decomposition stages of Casuarina equisetifolia in southern subtropical coastal zone, China, using the colorimetric assays. The time required for the loss of half of the initial dry weight (t₅₀) was 9.13 months. Total phenolics (TP), extractable condensed tannins (ECT), protein-bound condensed tannins (PBCT), total condensed tannins (TCT) and protein precipitation capacity (PPC) of branchlets litter decreased rapidly, while fibre-bound condensed tannins (FBCT) increased during decomposition. Nitrogen and phosphorus concentration of the branchlet litter both increased gradually during decay. Negative correlations between TP and nitrogen or phosphorus, as well as TCT and nitrogen or phosphorus were found. These chemical changes enhanced the current knowledge on the potential ecological role of nutrient transformation in tannins in C. equisetifolia plantations.

We aimed to evaluate the extractability of different extractants for zinc (Zn) and copper (Cu) in soils of long-term field experiments covering different agro-ecological zones of India. The relationships between the amounts of Zn and Cu extracted by Mehlich 3, 0.1 mol/L HCl and AB-DTPA (ammonium bicarbonate-diethylenetriaminepentaacetic acid) with those extracted by DTPA, the conventional extraction method widely used in soil testing laboratories in India, were elucidated. The treatments of the long-term experiments included control (no fertilizer), 100% NPK, 50%NPK + 50% N through FYM (farm yard manure) and a fallow soil. Some important physico-chemical properties of soil like pH, organic carbon, textural class, CaCO₃ content, etc. were analyzed. The NPK + FYM treatment was found to be the most effective treatment in terms of increased content of Zn and Cu in soils. The results showed that the amount of Zn and Cu extracted by Mehlich 3 were significantly correlated with that extracted by 0.1 mol/L HCl (r = 0.970** for Zn and r = 0.914** for Cu). Accordingly, Mehlich 3 and 0.1 mol/L HCl could be used effectively for estimating Zn and Cu availability in soils of India. However, Mehlich 3 was superior to all the other extractants used for the study.

The paper presents the contents of phosphorus and potassium available in soil, soil sorption properties against the activity of alkaline and acid phosphatase. The fertilisation applied involved P, K, Mg, Ca and S: (P K Mg Ca S), (K Mg Ca S), (P Mg Ca S), (P K Ca S), (P K Mg S), (P K Mg Ca) as well as nitrogen fertilisation at the following rates: 0, 50, 100, 150, 200, 250 kg N/ha. The application of high nitrogen rates with no liming applied resulted in an unfavourable increase in hydrolytic acidity and a decrease in the total bases, cation exchange capacity as well as the sorption complex saturation with bases. According to the criteria provided in PN-R-04023, the soil investigated can be classified as the 3^rd class with an average available phosphorus (P_E-R). The analysis of Luvisol salinity demonstrated that the unbalanced mineral fertilisation applied did not trigger any chemical degradation. Significant values of the coefficients of correlation were recorded between the activity of alkaline and acid phosphatase and the parameters investigated (hydrolytic acidity, total exchangeable, base stauration, P_E-R). The calculated enzymatic index of soil pH (AlP/AcP) ranged from 0.11 to 0.72.

Chlorine, one of the most abundant elements in nature, undergoes a complex biogeochemical cycle in the environment, involved in the formation of volatile organochlorines (VOCls), which in turn can contribute to environmental problems, contaminate natural ecosystems, and are of public health concern. Several industrial and natural sources of VOCls have already been identified; however, data - particularly on the natural sources - are still scarce. The aim of this study was to investigate the diversity of emission of VOCls from soil and several undergrowth plants collected in temperate spruce forest ecosystem and the effect of salting on the VOCl emission of plants. Undergrowth plants were found to emit chloroform (CHCl₃) in the range of 2.2-201 pmol/day/g dry weight (DW), tetrachloromethane (CCl₄) 0-23.5 pmol/day/g DW, and tetrachloroethene (C₂Cl₄) 0-13.5 pmol/day/g DW; the average emission rates were about 10 times higher than that of soil (2.9-47.2; 0-5.8; 0-3.6 pmol/day/g DW of CHCl₃; CCl₄; C₂Cl₄ emission, respectively). Addition of sodium chloride solution in most cases caused an increase in the emission of CHCl₃ and caused a species specific - effect on the emissions of CCl₄ and C₂Cl₄. The results suggest that the emission of VOCls from spruce forest contribute to the atmospheric input of reactive chlorine; however, on a global scale it is only a minor net source.

A pot experiment using root separation technique was conducted to further understand the effect of root interaction played in intercropping system under different nitrogen levels. The results showed that root interaction and increasing nitrogen application increased the green leaf area per plant and chlorophyll content of soybean, but their effects gradually decreased with increasing nitrogen fertilization level. Root interaction and increasing nitrogen application can improve photosynthetic characteristics of soybean, but root interaction only had a significant effect under low nitrogen level. The number of bacteria, fungi, actinomycetes and Azotobacteria was also obviously affected by root interaction and nitrogen fertilization, and the number of Azotobacteria presented a changing trend of first increased and then decreased with increasing nitrogen fertilization level. Root interaction and increasing nitrogen application improved soybean yield and its components, but their effects gradually decreased with increasing nitrogen fertilization level. The root activity of soybean was obviously affected by root interaction, and was significantly positively correlated with green leaf area per plant, chlorophyll content, photosynthetic rate and economic yield per plant. Our results indicate that the advantage effect of root interaction and increasing nitrogen application will be partially inhibited with an increasing nitrogen fertilization level.

Soil samples were collected at both jointing and maturing stages of maize and wheat to compare the effects of 4-year no-tillage (NT) and conventional tillage (CT) on seasonal variations of microbial biomass carbon (C), metabolic quotient, and invertase activity in a sandy loam soil in North China. Soil invertase activity significantly increased (P < 0.05) from summer to spring of the next year and then significantly decreased (P < 0.05) from spring to summer. With a delay of about 3 months, soil microbial biomass C and basal respiration altered in a similar pattern, while microbial metabolic quotient changed on the contrary. Compared with CT, the NT practice significantly increased (P < 0.05) soil organic C content, and tended to result in higher soil microbial biomass C and invertase activity, as well as lower soil microbial metabolic quotient, especially at the jointing stage of maize. Our results indicated that NT might play an important role in the improvement of soil microbial efficiency, especially at the maize seedling season.

The study should reveal the effects of soil texture and of seed characteristics of oilseed rape (Brassica napus L.) on seed survival in the soil by a burial experiment. Seeds of 58 conventional and new trait accessions (genetically modified and/or with altered seed ingredients) were buried for six months in sandy loam (SL), clay (c) or silty clay loam (SICL) in the seasons 2008/2009 and 2009/2010 in Germany. Between 84-93% (2008/2009) and 64-87% (2009/2010) of the conventional seeds survived in the soil, and so did 41-67% and 8-44% of the new trait seeds. Significantly more seeds were found in C and SICL compared to SL. Seed survival also significantly depended on the genotype, with high and low seed survival in both conventional and new trait accessions. Seed survival rates are probably linked with moisture and oxygen provided by different soils. As soils with good water storage conditions seem to have a higher probability for oilseed rape seeds from harvest losses to survive, other measures such as growing low dormancy varieties and proper soil tillage are especially relevant to avoid volunteers on these soils.

The aim of study was to compare the effect of farming methods on soil microbial communities and dehydrogenase activity (DHA). During 2008-2013, in the five-field crop rotation the following treatments were carried out: ORG - organic; ORGFYM - organic with cattle manure; CONFYM - conventional (cattle manure, mineral fertilizers and pesticides were used). From the treatments soil samples in three replicates were taken for microbiological tests in September yearly. Total bacteria and cellulose decomposing bacteria were determined as a number of colony forming units per g of dry soil. Soil DHA was determined in accordance with Tabatabai (1982). Solid cattle manure applied in the ORGFYM rotation increased significantly (P < 0.05) the number of total bacteria and cellulose decomposing bacteria (by 19.4% and 45.3%, respectively), and DHA by 22.7%. There appeared no clear and significant differences in effects between ORGFYM and CONFYM treatments, as an average of experiment period. In some cases, the use of certain pesticides in CONFYM treatment significantly affected the microbe numbers and soil DHA.