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The aim of this study was to determine the effect of sulphur (S) fertilization on macronutrient concentrations in the roots, straw and oil cake of white mustard and Indian mustard. The experiment was conducted in northeastern Poland (2006-2008). The highest content of N, P, K, Mg and S was noted in the oil cake of both mustard species. Sulphur fertilization increased S concentrations and had no effect on Mg concentrations in the roots of white mustard and Indian mustard. Sulphur fertilizers applied to soil significantly increased the content of N, K and Ca in the roots of Indian mustard, whereas they had no significant effect on the content of N, P and Ca, and decreased K concentrations in the roots of white mustard. Sulphur fertilization led to a significant decrease in N content, and an increase in the content of K and Ca in the straw of both mustard species. Sulphur fertilization significantly decreased P concentrations and increased S concentrations in the oil cake of both mustard species. In response to S fertilization, the content of N and K decreased in the oil cake of Indian mustard, but did not change significantly in the oil cake of white mustard. Therefore, S fertilization significantly differentiated the fertilizing value of post-harvest residues and the feeding value of white mustard and Indian mustard seeds.

Limited water resources restrict winter wheat grain yield and quality in the Huang-Huai-Hai Plain of North China, and establishing optimal planting patterns according to crop water requirements is the key factor for achieving rational water use. In this paper, 4 planting patterns were applied, namely, uniform row (30 cm; traditional pattern), wide (40 cm)-narrow (20 cm) row, furrow (double lines in the furrow with 20 cm spacing, and 40 cm between furrows), and seed bed (double lines on the bed with 20 cm spacing, and 40 cm between beds). Each planting pattern was irrigated twice during the jointing and heading stages, and total irrigation water was controlled at 120 mm. Grain yield was significantly (LSD, P < 0.05) higher in the furrow planting pattern than in the uniform row, wide-narrow row, and seed bed planting patterns, by 73.4, 64.3, and 53.4 g/m², respectively, in 2004-2005 and by 54.3, 42.6, and 30.2 g/m², respectively, in 2005-2006, mainly because of a significant (LSD, P < 0.05) increase in the spike and kernel numbers. These results were caused by changes in the contribution of dry matter remobilization to grain yield (CDMRG); the CDMRG was higher in the furrow planting pattern than in the uniform row, wide-narrow row, and seed bed planting patterns by 5.1%, 4.3%, and 2.9%, respectively. Gliadin and glutenin contents in the furrow planting pattern were 4.67% and 5.85%, respectively, and were significantly (LSD, P < 0.05) higher than those in the uniform row, wide-narrow row, and seed bed planting patterns; however, the furrow planting pattern had no significant (LSD, P < 0.05) effect on albumin and globulin contents. Dough development time (DDT) and dough stable time (DST) in the furrow planting pattern were 5.6 min and 8.8 min, respectively; they were significantly (LSD, P < 0.05) improved compared to those in the uniform row, wide-narrow row, and seed bed planting patterns; however, there were no significant (LSD, P < 0.05) differences in dough breakdown time (DBT) between any of the planting patterns. These results suggest that the furrow planting pattern combined with deficit irrigation during the jointing and heading stages can be applied to winter wheat production in the Huang-Huai-Hai Plain of North China.

A field experiment was conducted in 2008-2010 at the Experimental Station of the Faculty of Agricultural Sciences in Zamość (50°42'N, 23°16'E), University of Life Sciences in Lublin. The aim of the study was to assess the impact of cropping method and weed control methods on the content of Cu, Zn, Fe and Mn in maize and on their uptake. Two cropping methods were studied - sole cropping and strip cropping (common bean, dent maize and spring barley in adjacent strips) and two weed control methods - mechanical and chemical. Strip cropping reduced Mn content in maize, did not significantly affect Zn content, and increased accumulation of Cu and Fe. The content and uptake of the elements by maize depended on the position of the row in the strip and on the adjacent plant species. Placement next to beans resulted in higher Fe and Zn content, while placement next to barley increased Cu content. The highest Mn content was noted in maize from the centre row. In general, micronutrient uptake by maize was lowest in the middle row. These results indicate that strip cropping can be an effective agricultural practise for plant biofortification.

This study aims to explore the optimum nitrogen (N) application method by analyzing effects of variable N application stages and ratios on the N absorption and translocation of high-yield summer maize (DH661). The study included field experiments and ¹⁵N isotopic dilutions for pot experiments. Results showed that the yield was not increased in a one-off N application at the jointing stage. The uptake of fertilizer-derived N in the grain increased with the increasing of N applied times. Compared to a single or double application, total N uptake (N_up) and biomass increased significantly by supplying N at the six-leaf stage (V6), ten-leaf stage (V10) and 10 days after anthesis in ratios of 3:5:2 and 2:4:4. The fertilizer-derived recovery rates were 67.5% and 78.1%, respectively. The uptake and utilization of fertilizer-derived N was enhanced by increasing the recovery rate of N supplied after anthesis, and reducing the absorption of soil-derived N. Therefore, the 2:4:4 application ratios was the optimal N application method.

Influence of CULTAN system (controlled uptake long term ammonium nutrition) on the nitrogen uptake by spring barley (Hordeum vulgare L.) was observed at 5-year small-plot field experiments under conditions of the Czech Republic (central Europe). Nitrogen uptake by CULTAN-fertilized plants was more even during vegetation period probably due to delayed term of fertilizer application. Nitrogen concentration in the aboveground biomass at BBCH 51 and in straw had no effect on grain yield. Post-heading nitrogen uptake as well as contribution of nitrogen translocation to total nitrogen in grain did not differ among both nitrogen fertilization treatments. Increase in grain size of spring barley by the CULTAN system can be explained by tendency to lower number of ears per area rather than by prolonged nitrogen uptake from soil. Lower protein content in grain of CULTAN-fertilized spring barley can be caused by increase in grain retained on a 2.5 mm sieve and also decrease in total nitrogen concentration in above-ground biomass at BBCH 51. No significant effect of CULTAN treatment on nitrogen use efficiency and nitrogen uptake efficiency was recorded. Significantly higher nitrogen utilization efficiency at CULTAN treatment could be explained by lower grain protein content compared to conventional treatment.

How light conditions affect development of park grasslands is a question that has not been satisfactory addressed. The aim of this study was therefore determination of the level to which unfavorable light conditions influence grassy parks area and relationships between parameters which determine state of turf grasses. Researches were conducted in two parks in Warsaw, in various light conditions and included measurement of: leaf density, sward height, leaf area index (LAI), and botanical composition of the communities. The leaf density of shaded areas did not exceed 70%. LAI value varied from 0.5 to 0.9-fold lower than in the areas in half-shade and in sun. The participation of basic lawn species at Skaryszewski Park was higher under shade, while at Łazienki Królewskie was higher in full-sunlight areas. The state of tested grassy areas in limited solar radiation does not satisfy the requirements of recreational and representational functions. The development processes of vegetation coverage were inhibited at the sites of lower solar radiation. LAI was influenced by both leaf coverage and sward height. Agrostis stolonifera and Poa trivialis may be recommended to create grass areas under limited solar radiation.

In 1998-2000, in a multi-factorial field experiment established by the method of split blocks and subplots, we studied the effect of three systems of beet tops management, two sowing rates and two levels of N fertilization and the effect of interactions of the factors on production and qualitative indicators of spring barley varieties Amulet and Kompakt. The evaluation shows the dominant effect of the particular year on the variability of all characters. The proportion of the effect of the year on the variability of characters ranged from 2.1 (number of plants per m2) to 80.1% (yield). The variability of quality parameters was also considerably affected by the genetic factor of the variety (grain over2.5 mmsieve 40.4%, TGW 20.5%). The level of characters was greatly variable in relation to the course of climatic conditions of the year. The highest grain yield was achieved in 1999 (7.21 t/ha), the lowest one in 2000 (5.25 t/ha). The best quality parameters were shown by grain from the 1998 harvest (yield 6.20 t/ha) with significantly highest TGW (47.76 g), a high proportion of grain over2.5 mmsieve (92.01%, 5.54 t/ha) and a favourable content of N substances in the grain (10.60%). Ploughed down beet tops supported the creation of the yield, the average differences between variants were, however, minimal being heavily affected by the course of weather in particular years. More favourable conditions for the creation of the yield (6.17 t/ha) and for the formation of mechanical properties of the spring barley grain (TGW45.55 g, grain over2.5 mmsieve 85.86%) were produced by variants with late ploughing down beet tops, the smallest accumulation of N substances occurred in variants with harvested beet tops (11.83%). Sowing rate significantly affected values of all studied characters. Variants sown 4.5 MGS (6.27 t/ha) gave higher average grain yields, grain of better quality was obtained from the stands sown 3.5 MGS (TGW45.22 g, grain over 2.5 sieve 84.41%, N substances 11.93%). Between particular varieties, significant differences were found both in the economic yield and the grain quality. The Kompakt variety showed on average 4.7% higher yield (6.37 t/ha) than the Amulet variety which, however, reached the higher average TGW values as well as the proportion of grain over2.5 mmsieve (45.87 g, 88.24%). The grain quality of the Amulet variety was negatively affected by the increased accumulation of N substances in the grain (12.49%). As compared with control, N fertilization at the rate of 30 kg/ha showed significant increase in the yield in 1998 only (by 7.5%) while in other years, an increase in the yield was not noticed. In all years under investigation, the TGW values and the proportion of grain over2.5 mmsieve decreased and the content of N substances in grain increased after application of N at the rate of 30 kg/ha.

Field experiments were conducted at two different locations (Barani Agricultural Research Institute Chakwal and farm field Talagang, district Chakwal) for two crop-growing seasons in northern rainfed Punjab, Pakistan to assess the yield and micronutrient uptake of chickpea (Cicer arietinum). The treatments were four combinations of two levels of sulfur (15 and 30 kg/ha) from two sources (gypsum and ammonium sulfate) and a no-sulfur control. Application of sulfur resulted in a significant increase in seed yield up to 17% over control. Ammonium sulfate was a more efficient source of sulfur as compared to gypsum at both the locations. Sulfur application resulted in a significant increase in micronutrient uptake by plant; however effect of sulfur application on soil pH at the end of experiment was not significant. Availability of soil zinc and copper increased with sulfur application at the end of two year experiment. Tissue copper and iron and soil available copper and iron correlated negatively with soil pH. Sulfur should be applied to chickpea grown under rainfed conditions in order to increase seed yield, to improve nutritional composition of product and to enhance efficiency of other fertilizers.

The effects of land use practices on soil fauna, especially earthworms, are poorly known in coastal saline agricultural soils. Here we compare earthworm communities in six types of land use practice in the coastal region of China's Bohai Bay, namely uncultivated saline soil, two orchard (pear and winter jujube) lands, man-made forests (chinese ash), vegetable land and cropped land (maize). In addition, we recorded selected physicochemical properties of the soil. Soil organic matter content and total N were significantly higher under pear orchard and vegetable land than under the other land use practices, and their lowest values were observed from uncultivated saline soil. Vegetable land and pear orchard land showed a significantly higher abundance of earthworms than the other land use practices, whereas no earthworm was found in uncultivated saline soil. The sites under individual practices supported one to three earthworm species. Aporrectodea trapezoides species was present under four types of land use practice, and the biomass of this species accounted for more than 60% of the community. Vegetable land and pear orchard land supported richer earthworm community than the other land use practices, dominated by Aporrectodea trapezoides and Drawida japonica. These preliminary results indicated that land use practices have substantial effects on the abundance and composition of earthworm communities in saline soils.

The effects of mineral and organic fertilization on the contents of Fe, Cu, Zn, Mn, B and Mo in soil and in the soil solution as well as on availability of these elements for crops were investigated in the long-term field trial. The highest contents of Zn, Fe, Mn and Cu in soil and soil solution were observed in the treatment with the lowest pH (NPK). In this same combination the content of B and Mo was the lowest. The concentration of Zn, B and Fe in the soil solution significantly increased under farmyard manure application. Liming significantly decreased contents extractable by 1 mol/L HCl forms of Mn and Zn and significantly increase the content of Mo in the soil. Regardless of fertilization applied, microelement concentrations in the soil solution are sufficient for fulfilling nutritional needs of plants cultivated during the trial.

It has been demonstrated that endophyte-infected (EI) ryegrass performed better in response to N deficiency than its endophyte-free (EF) counterpart. When P is considered, there is a lack of related information. In this study, Lolium perenne L. infected with Neotyphodium lolii was employed to establish EI and EF populations. Soil-grown EI and EF ryegrass were tested for their responses to P deficiency. The results showed that the endophyte infection improved the adaptability of ryegrass to P deficiency. When P was limited, EI roots were significantly longer (EI, 398.8; EF, 323.4 m/pot) and heavier (EI, 30.58; EF, 23.20 g/pot) than EF roots; the root: shoot ratio of EI plants was greater than that of EF plants (P < 0.05). The content of total phenolics and organic acids was significantly greater for EI roots than for EF roots at low P supply; the concentration of both, however, was not improved by the endophyte infection. This suggested that it was the higher root dry weight (DW) that contributed to the higher content of total phenolics and organic acids for EI plants, and the endophyte infection might have negligible effects on chemical modification of perennial ryegrass. Endophyte infection did not increase P uptake rate but did significantly improve P use efficiency of ryegrass in response to P deficiency (EI, 0.734; EF, 0.622 g DW/mg P).

Agricultural practices that reduce soil degradation and improve agriculture sustainability are important particularly for dry hilly land of Chaoyang County in the Liaoning Province, North-east China, where cinnamon soils are widely distributed and mainly for wheat production. The impacts of 10-year cropping systems (wheat-cabbage sequential cropping, wheat-corn intercrop, wheat-sunflower rotation, wheat-soybean rotation) on soil enzyme properties of surface-soil (0-20 cm) were studied. Total carbon, nitrogen, phosphorus and sulfur, and nine soil hydrolases related to nutrient availabilities (β-galactosidase, α-galactosidase, β-glucosidase, α-glucosidase, urease, protease, phosphomonoesterase, phosphodiesterase, arylsulphatase) and five enzymes kinetic characters were examined. Wheat-corn intercrop systems had higher total C, total N, total P and total S concentrations than wheat-soybean and wheat-sunflower rotation systems. Most test enzyme activities (α-galactosidase, β-galactosidase, α-glucosidase, β-glucosidase, urease, protease, phosphomonoesterase and arylsulphatase) showed the highest activities under wheat-corn intercropping system. Urease, protease and phosphodiesterase activities of wheat-cabbage sequential cropping system were significantly higher than two rotation systems. The maximum reaction rates of enzymes (V_max) were higher than apparent enzyme activity, which suggests larger potential activity of enzymes, while not all kinetic parameters were adaptive as soil quality indicators in dry hilly cinnamon soil.

The influences of arbuscular mycorrhizal (AM) fungus on growth, gas exchange, chlorophyll concentration, chlorophyll fluorescence and water status of maize (Zea mays L.) plants were studied in pot culture under well-watered and drought stress conditions. The maize plants were grown in a sand and black soil mixture for 4 weeks, and then exposed to drought stress for 4 weeks. Drought stress significantly decreased AM colonization and total dry weight. AM symbioses notably enhanced net photosynthetic rate and transpiration rate, but decreased intercellular CO₂ concentration of maize plants regardless of water treatments. Mycorrhizal plants had higher stomatal conductance than non-mycorrhizal plants under drought stress. The concentrations of chlorophyll were higher in mycorrhizal than non-mycorrhizal plants under drought stress. AM colonization significantly increased maximal fluorescence, maximum quantum efficiency of PSII photochemistry and potential photochemical efficiency, but decreased primary fluorescence under well-watered and droughted conditions. Mycorrhizal maize plants had higher relative water content and water use efficiency under drought stress compared with non-mycorrhizal plants. The results indicated that AM symbiosis alleviates the toxic effect of drought stress via improving photosynthesis and water status of maize plants.

The adverse effect of the application of phosphorus (P) on arsenic (As) adsorption by soils can result in increasing mobility and availability of As. However, in different soils, P might influence As adsorption differently. In this study, the arsenate [As^(V)] adsorption capacities of six soils with different properties and the effects of P application were studied. The results indicated that the adsorbed As^(V) contents all increased as a function of the As^(V) content in equilibrium. When analysed using the Langmuir and Freundlich equations, the maximum As^(V) adsorption capacity of 0.72 mg/g was found for an Alumi-Plinthic Acrisol, while the minimum capacity of 0.09 mg/g was observed for an Epigleyic Cambisol. The adverse effects of P application on As^(V) adsorption by the six soils were observed to be variable. When the P/As molar ratio in a culture experiment was increased from 0 to 10, the maximal and minimal decreases in the As^(V) adsorption capacity of 0.086 and 0.014 mg/g were found in the Alumi-Plinthic Acrisol and Epigleyic Cambisol, respectively. P was relatively more effective in competing for adsorption sites with As^(V) in the Alumi-Plinthic Acrisol and Luvi-Endogleyic Phaeozem due to their higher A/P values (decrease in adsorbedAs/added P) of 1.143 and 1.135, respectively. These results will help decrease the environmental risk of some As-contaminated agricultural soils through the controlled application of P.

The purpose of the studies was to determine the species composition of fungi and their antagonistic effect towards soil-borne plant pathogens after the cultivation of oats, spring vetch and tansy phacelia as intercrop cover plants. The total population of fungi in the soil after the cultivation of oats was twice as low as after the cultivation of tansy phacelia. A little smaller fungi population was obtained as a result of mulching the soil with spring vetch in comparison to that after the cultivation of tansy phacelia. The proportion of Fusarium spp., Alternaria alternata, Pythium irregulare and Thanatephorus cucumeris isolated from the soil after the cultivation of oats was the lowest one, while being a little higher after the cultivation of spring vetch, and the highest after tansy phacelia. The greatest number of antagonistic fungi occurred in the soil after ploughing in the mulch of oats. Antagonistic fungi isolated from the soil mulched with oats were the most effective in limiting the growth and development of A. alternata, Fusarium culmorum, F. oxysporum, Haematonectria haematococca, P. irregulare and T. cucumeris since the value of their antagonistic effect was the largest. The lowest antagonistic activity of fungi was found out after using tancy phacelia.

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.

Soil pollution of fluorine is a serious environmental problem in the world, and the fluorine pollution evaluation of spatial and vertical distribution study in the Karst region is quite limited. In this study, the farmland around lead-zinc mine in the Karst region was chosen as the study area. Ninety-one upper layer soil samples and two soil profiles (one in paddy field, the other one in aerated field) samples were taken. The average concentration of total fluorine of topsoil in the paddy fields is 378 mg/kg, whereas in the aerated field it is 508 mg/kg. The concentrations of total fluorine in all paddy soil samples and 97.87% aerated field soils are higher than that of the background value of Guangxi. The total fluorine contaminations in all aerated field soils are much higher than in paddy soil samples, so the aerated field is contaminated severely. The vertical distribution of fluorine is different in paddy field and aerated field. In paddy field, the content of fluorine increases from 20 to 40 cm, then it decreases rapidly from 40 to 60 cm in depth, and then increases gradually. However, in the aerated field, the content of fluorine rises gradually with the depth of the sampling point. The results of relative analysis and regression analysis between fluorine in soil and soil properties show that the spatial distribution and vertical variation of fluorine in this region are mainly affected by parent rock.

The effects of phosphorus (P) fertilizer on P loss potential, soil Olsen-P and neutral phosphatase activities in paddy soils fertilized with superphosphate or pig manure (PM) were evaluated in this paper. Data were collected from a field experiment in the Tai Lake Basin, China. Superphosphate rates were 0, 17.5, 26.7, and 35.0 kg P/ha, and PM rates were 0, 1.4, 2.1, and 2.8 t/ha for each crop, respectively. Soil Olsen-P in the plow layer increased to a greater extent with PM than with superphosphate. Pig manure increased neutral phosphatase activities in the plow layer compared with PM-free treatment. In contrast, superphosphate inhibited neutral phosphatase activities compared with superphosphate-free treatment. Spring application of P fertilizer markedly increased the total P of surface water in November (< 0.01 vs. 0.10 mg/L) compared with P-free treatment. The total P of shallow groundwater at a 75 cm depth was ~0.01 mg/L. Phosphorus fertilizer did not influence Olsen-P or neutral phosphatase activities under the plow layer. Downward movement of P did not occur. Appropriate rate of P application of 26.2 kg P/ha for each crop in this soil reduced the risk of P loss in the paddy wetland ecosystem.

The aim of this study was to investigate the impact of used technology and environmental condition on lucerne dry matter yield in the regional conditions. During a three year period (2011-2013), the investigation was based on management survey in 27 farms in the Czech Republic. Climate conditions significantly influenced yield in some interaction with soil where only combination of dry climate and less fertile soil conditions reduced forage yield. The single soil effect was not significant for forage yield. Applied technology was influenced by both environment and farm characteristic (such as farm size and cow's milk performance) which together significantly explained about 40% of variability of used technological properties. From all investigated technological properties, only cultivation of lucerne in mixture with grasses consistently increased forage yield therefore should be considered as important factor for modelling forage farm yield in the regional conditions.

Pea seeds were swollen in solutions with different concentrations of cytokinin benzyladenine (BA). As compared with controls, a low concentration of BA (0.05 mg/l) did not affect the growth of stems and roots of twelve-day-old seedlings but concentrations of 0.20-4.00 mg/l showed an inhibiting effect; this inhibition was proportional to the concentration of BA. In controls the ratio between the lengths of stems and roots was equal to 1.14, while in seedlings influenced by BA in concentration of 0.20 mg/l its value was significantly lowered to 0.91. Also in six-day-old pea seedlings cultivated under in vitro conditions, BA concentrations of 0.70 and 3.30 mg/l inhibited the growth of roots and epicotyls and significantly increased the production of ethylene (by 150 and 330%, respectively). Three hours after the amputation of the root of five-day-old pea seedlings the level of cytokinin trans-zeatin increased in the apical part of the stem. Within the interval of 48 hours after the amputation of the root the concentration of this plant hormone gradually decreased again. The initial increase in the zeatin level in the stem indicates that the absence of the root induces a reduction of growth-inhibiting effects of roots, which negatively influences the zeatin level in the stem apex at the beginning of germination.

The present study was undertaken to sequentially fractionate nickel (Ni) in soils of divergent physicochemical characteristics and evaluate the contribution of different fractions towards plant uptake. For this, fifteen bulk surface (0-15 cm) soil samples were collected from the cultivated fields of northwestern Indo-Gangetic alluvial plains. A pot experiment was conducted with these soils to assess the contribution of soil Ni fractions to plant uptake using soybean as test crop. Results showed that residual Ni was the most dominant fraction in soil constituting 3.19-63.6% of total Ni. The water soluble plus exchangeable Ni accounted for only 0.70-4.04% of total soil Ni. Organically bound Ni varied from 1.60-6.85% of total Ni; these values are relatively lower as compared to those reported for temperate soils. Correlation studies showed that the free iron oxide (Fe₂O₃) and soil organic carbon correlated with various fractions of Ni in soil. Water soluble plus exchangeable and organically bound are the dominant fractions which contributed positively and manganese oxide (MnO₂) bound and residual fractions contributed negatively towards the phytoavailability of Ni in soil.

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.

Soil water content under no fertilizer (NF), fertilizer (F) (N:30; P₂O₅: 45 kg/ha), and fertilizer plus pig manure (FO) (N:30; P₂O₅: 45 kg/ha; pig manure 15 000 kg/ha in 2003; and 30 000 kg/ha in 2004 and 2005) treatments was measured using neutron probe instrument for a period three years in a long term field experiment in order to investigate the impact of different fertilization treatments on Haploborolls soil water content. Fertilization had significant effects on the soil water content. FO treatment had greater soil water content in 10 cm depth than F treatment with average 9.9% increase (P < 0.05) but lower than NF treatment; however, in the depth from 30 to 90 cm, there was no water content difference between F and FO treatments. Treatment with organic amendments reduced total soil water content on the long term experiment basis. Across the three years, no fertilizer treatment had total soil water content higher by 1.2% and 3.1% than fertilizer treatment and fertilizer plus pig manure treatment within 10 to 210 cm soil profile in most of the months, respectively.

A 75-day pot experiment was carried out to study the effect of growth of ryegrass (Lolium multiflorum L.) on degradation rate of spiked phenanthrene (the concentration was 5, 50, 200 mg/kg) in soil. The results showed that ryegrass growth enhanced the degradation of phenanthrene spiked in the soil, thus making the content of extractable phenanthrene lower (P < 0.05) in the ryegrass planted pots than that of pots without ryegrass. In the treatments of 5, 50 and 200 mg/kg of phenanthrene, phenanthrene degradation rate reached 81.1, 90.4 and 85.0%, respectively, while in pots without ryegrass they were only 73.5, 86.2 and 67.6%, respectively, and ryegrass growth shorted phenanthrene half-life. Ryegrass growth enhanced activities of polyphenol oxidase, dehydrogenase and increased the content of microbiological biomass carbon, thus raised the degradation rate of phenanthrene in the soil. High concentration of phenanthrene inhibited soil biological activity, and in turn the effect of soil biology on phenanthrene degradation. Therefore, the findings disclose the biological and enzymological mechanisms of the plant enhancing phenanthrene degradation. It was also found that ryegrass is rather tolerant to polycyclic aromatic hydrocarbons, but high phenanthrene concentration affected ryegrass growth.

Changes of free amino acid (AA) contents (glutamic acid, glutamine, aspartic acid, asparagines, proline, hydroxyproline) in Noccaea caerulescens and Arabidopsis halleri under cadmium soil contamination (Cd1 = 30, Cd2 = 60, Cd3 = 90 mg/kg soil) are reported. Results of the pot experiment confirmed different effect of Cd on N. caerulescens in contrast to A. halleri and the higher stress adaptation of A. halleri. Total free AA contents in both plant species were not significantly modified by Cd contamination. The glutamic acid and glutamate contents in plant biomass were decreased under Cd2 and Cd3 stress. The declines of contents of both AA can be caused by intensive syntheses of plant defense elicitors, but declines in A. halleri were significantly lower in contrast to N. caerulescens. The content of aspartic acid was increased in N. caerulescens under Cd stress, but in A. halleri its changes were not observed. The different pathways of nitrogen utilization of tested plants were confirmed: the major AA forms used for nitrogen transport are glutamate for N. caerulescens and asparagine for A. halleri. The increase of proline content was determined only in N. caerulescens growing under Cd stress in the beginning of growing period.

To better understand the potential for improving biomass accumulation and radiation use efficiency (RUE) of winter wheat under deficit irrigation regimes, in 2006-2007 and 2007-2008, an experiment was conducted at the Luancheng Experimental Station of Chinese Academy of Science to study the effects of deficit irrigation regimes on the photosynthetic active radiation (PAR), biomass accumulation, grain yield, and RUE of winter wheat. In this experiment, field experiment involving winter wheat with 1, 2 and 3 irrigation applications at sowing, jointing, or heading stages was conducted, and total irrigation water was all controlled at 120 mm. The results indicate that irrigation 2 or 3 times could help to increase the PAR capture ratio in the later growing season of winter wheat; this result was mainly due to the changes in the vertical distributions of leaf area index (LAI) and a significant increase of the LAI at 0-20 cm above the ground surface (LSD, P < 0.05). Compared with irrigation only once during the growing season of winter wheat, irrigation 2 times significantly (LSD, P < 0.05) increased aboveground dry matter at maturity; irrigation at sowing and heading or jointing and heading stages significantly (LSD, P < 0.05) improved the grain yield, and irrigation at jointing and heading stages provided the highest RUE (0.56 g/mol). Combining the grain yield and RUE, it can be concluded that irrigation at jointing and heading stages has higher grain yield and RUE, which will offer a sound measurement for developing deficit irrigation regimes in North China.

Declining water is a great concern in production of rice, because rice is more sensitive to water deficiency which restricts normal rice growth resulting in enormous economic loss. A field experiment was conducted to study the effect of hydrogel in different sowing techniques of aerobic rice viz. flat, ridge, and bed sowing. Observations on soil moisture percentage before every irrigation, yield, and yield components of rice were recorded. Application of hydrogel improved soil moisture contents in all the three sowing techniques as compared to soil without hydrogel. More soil moisture contents met the crop water needs and increased the number of germinated seeds. As a consequence of more emergence and better stand establishment, the yield components were also improved increasing the yield of rice in hydrogel amended soil in all sowing techniques. However, sowing of rice on beds with hydrogel amendment was found the most effective; it not only improved the performance of aerobic rice but also enhanced growth and yield of aerobic rice more than other sowing techniques.

One of the factors frequently affecting yields is topography. Topographic data can be obtained from various sources with different precision. This work evaluates suitability of airborne laser scanning data for use as another source of topographical characteristics creation in a smaller scale in regards to precision agriculture needs. Simple models of elevation, slope and flow accumulation were created and the correlation between yield and topography was determined over a seven-year period in relation to precipitations and temperature. The suitability of airborne laser scanning data was proved with certain limitations. Flow accumulation model derived from original airborne laser scanning data indicated the right trend of flow accumulation but not as clearly compared to other models. In drier years the correlation coefficients between flow accumulation and yield reached up to 60-70%.

Opium poppy (Papaver somniferum L.) is currently an important agricultural commodity, with the product being used in the food industry (seed) as well as in the pharmaceutical industry (morphine and other alkaloids). Intensive production of poppy leads to a specific direction of breeding with the aim to obtain highly productive cultivars of the so-called food industry or industrial type. The paper evaluates 57 genetic resources (mostly cultivars), comparing the groups of values representing the indicators of production-significant morphologic and agricultural characters (capsule size; morphine content in poppy straw; weight of dry, empty capsule) and content of morphine in the poppy straw, in relation to the ideotype of poppy, which in these indicators represents 100% of the value. On average lower values in the above indicators were achieved by cultivars with white-coloured seed, including morphine content; concrete data are specified in three cultivars with morphine content in the poppy straw above 0.40%. In blue-seed to grey-seed cultivars, except for the high-morphine cultivar Buddha (1.85% of morphine), we found only six materials with a minimum morphine content of 0.8% in the poppy straw (maximum of 0.92%). These genetic resources also achieved very good values in the morphological indicator and average value in the economic indicator. The results will be used in the selection and classification of suitable genetic resources of poppy in breeding of industrial forms.

Change in the community of epigeal spiders and harvestmen (Araneae, Opiliones) was studied in an experimental apple orchard for six consecutive years. Five plots were surveyed by pitfall traps. Four of the plots were young (1-4 years); one plot was older (15-20 years). The abundance of epigeal arachnids increased with the age on the young plots, while it was constant on the older plot. There were significantly more arachnids on the young plots than on the older one. In turn, the diversity was significantly lower on the young than on the older plots. Lycosidae, Phalangiidae and Tetra-gnathidae dominated the young plots. The older plots were richer in Agelenidae, Clubionidae, Dysderidae, Gnaphosidae, Linyphiidae, Pisauridae and Salticidae. Principal species of the young and older plots were identified using multivariate analysis.