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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.

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.

A field experiment was conducted on rendzina soil in the years 2010-2012. The seeds of two linseed cultivars (Szafir and Oliwin) were sown at row spacing of 15 cm and 25 cm. Three agrotechnical levels in different nitrogen doses and with or without application of herbicides were used. The objective of the study was to evaluate the effect of row spacing on yield, seed protein and oil content of two linseed cultivars grown under different conditions of mineral fertilization and chemical weed control. Results showed that cv. Szafir was characterized by significantly higher seed yield (on average by 20.2%) and protein content (by 2.6%) while cv. Oliwin had higher content of oil (by 4.9%). Intensive technology of cultivation (80 kg N/ha, Linurex 50 WP, Fusilade Forte 150 EC, Glean 75 WP), compared to the economical technology (40 kg N/ha, without herbicides), significantly increased the seed yield of both linseed cultivars (on average by 80-102%). This was due to higher plant density, higher number of branches, and higher number of capsules per plant. The intensive technology of cultivation had a beneficial effect on the content of α-linolenic acid in linseed seed.

The experiments were laid out to understand the mechanisms causing yield limitations imposed by post-anthesis water and nitrogen deficiencies in plants with modified source-sink ratios. Two soil-water regimes were allotted to the main plots. At anthesis, three levels of N were applied: none, 25% and 50% of total the N supply. Spike-halving caused reduction in grain yield at both water regimes and all N supply levels, showing that the reduction in grain number can not be compensated by a higher individual grain weight. Sink reduction by trimming 50% of the spikelets reduced grain number per ear by 38.5% and increased individual grain weight by 12.0%, which shows the plasticity in grain weight and grain set of wheat if sufficient assimilates are available. Additional nitrogen supply at anthesis had no significant effect on the total aboveground biomass, but increased grain yield through more allocation of dry matter to grains. Our findings suggest that for rainfed wheat with optimum N supply and supplemental irrigation, wheat growers should choose cultivars with a high grain number per ear and manage the crop to increase grain number per unit of land (sink capacity).

For the purposes of assessment of long-term changes, two sets of Chernozems soil samples were analysed and compared in parallel: 'old' file samples obtained during the Soil Survey 1960-1970 in the former Czechoslovakia and a 'present' (2013) set of samples from exactly the same sites as the archive samples. The recently collected samples revealed worse qualitative parameters (lower humic acid to fulvic acid (HA/FA) ratios and higher colour quotient Q4/6 values) than the file samples, for all the localities. On the other side, the quantitative soil organic matter (SOM) parameters (oxidizable carbon (C_ox) and all its determined components) showed contrary results. The amount of total SOM at the same sites is higher now than it was about 50 years ago. It can be concluded that the current decline in SOM quality in Chernozems is partly compensated for by higher accumulation of SOM in the soils. All the analysed Chernozem samples were found to have much worse qualitative SOM parameters than the values mentioned for this soil type in the older literature. However, a comparison of the current data and the file data of Chernozem SOM quality can still be considered an open issue and require more complex research.

Soil organic carbon (SOC) plays a critical role in rice production, but its feedback to the fate of fertilizer nitrogen (N) is not clear. In this study, a pot experiment was conducted to investigate the responses of rice yield and the fate of fertilizer N to different SOC levels using ¹⁵N-labelled urea. The results showed that rice biomass, yield and the total N uptake increased significantly with increasing SOC content. Both rice N uptake from soil and urea increased significantly with increasing SOC content. The recovery rate and residual rate of fertilizer N improved significantly with increasing SOC content, leading to a reduced rate of not-specified fertilizer N. Therefore, it was concluded that high SOC could not only improve rice yield and fertilizer N recovery, but also could increase the retention of fertilizer N and decrease the not-specified N in the paddy soil.

In this study, a simulation experiment by farm warming with infrared ray radiator was carried out, and results showed that the broad bean (Vicia faba L.) growing days were shortened by increased temperature. The seedling, ramifying, budding, blooming, podding, and maturing stages were shortened by 1-4, 1-2, 1, 2-3, 1-2, and 2-4 days, respectively, and the whole growing period was shortened by 7-16 days when the temperature increased by 0.5-2.0°C. The broad bean yield increased by 10.1-16.6% when the temperature increased by 0.5-1.0°C, and significantly decreased by 38.1-90.1% when the temperature increased by 1.5-2.0°C. Increased temperature significantly improved the fat, carbohydrate, ash and energy contents.

The complex interaction process of the abiotic factors (sunlight, air temperature and soil water) in regulating maize (Zea mays L.) photosynthesis has not been fully understood. Our field experiment explored the changed sensitivity (or role) of the abiotic factors in regulating maize photosynthesis under a drought development process. The experiment established a scenario with a long-term drought and an instantaneous cloud cover. The results revealed that long-term drought stress causes the sensitivity (or role) of sunlight and temperature exchanged in regulating maize photosynthesis. The maize photosynthesis was more sensitive to instantaneous sunlight rather than temperature in the absence of drought. However, a diminishing photosynthetic sensitivity to sunlight but an increasing photosynthetic sensitivity to temperature was observed with drought development process. The variable photosynthetic sensitivity indicated that the roles of temperature and sunlight in regulating maize photosynthesis were exchanged, so it is expected that higher photosynthetic rate could be achieved by adjusting temperature rather than sunlight after severe drought. Nevertheless, further studies are needed to provide more evidence and mechanism explanations.

The purpose of the present studies was to determine the antagonistic effect of bacteria Bacillus spp. and Pseudomonas spp. towards selected fungi from the soil environment of carrot. Oats (Avena sativa L.), tansy phacelia (Phacelia tanacetifolia Bentham) and vetch (Vicia satica L.) were used as cover crops in the cultivation of this plant. In the traditional cultivation of carrot the population of bacteria was the smallest, while after the application of oats it was the largest. Laboratory tests showed that cover crops promoted the development of antagonistic Bacillus spp. and Pseudomonas spp. Irrespective of the experimental treatment, those bacteria were the most effective in limiting the growth and development of Fusarium oxysporum and Thanatephorus cucumeris (syn. Rhizoctonia solani), while being less effective towards Altenaria dauci and Alternaria radicina, and the least towards Sclerotinia sclerotiorum. The best total antagonistic effect of Pseudomonas spp. and Bacillus spp. towards the tested fungi was found after using oats and vetch, while the worst - in the traditional cultivation of carrot.

Potato (Solanum tuberosum L.) is a plant typical mainly for temperate climate and develops best at about 20°C. Heat stress due to increased temperatures is an agricultural problem in many areas in the world. The aim of our work was to assess the response of selected new potato cultivars to heat and drought stress during the subsequent stages of plant growth starting from buds forming. The pot experiment was carried out over the course of two years with the following early cultivars: Lord, Miłek, Gwiazda, Hubal, Oberon and Tetyda. The impact of heat (38°C/25°C) and drought stress on potato plants was tested in four periods of two weeks. In these periods half of the plants were watered to a level close to optimal while the other half remained without irrigation. Our studies demonstrated that tested potato cultivars' response to heat stress depends on the growth stage, in which the temperature acts on the plants and on the soil moisture. Besides the decrease in yield and tubers' diminution, the biggest problem was the presence of tubers with physiological defects, particularly of immature tubers. The response of cultivars was differentiated.

Soils harbour enormously diverse bacterial communities that interact specifically with plants generating beneficial interactions between them. This study was the first approach to assess bacterial communities before sowing with three cotton genotypes, including both transgenic and conventional ones. The structure of bacterial communities was identified using the next generation sequencing analysis, ion torrent PGM (Personal Genome Machine™) sequencer technology, based on the V2-V3 16S rRNA gene region. Quantitative insights into microbial ecology pipeline were used to identify the structure and diversity of bacterial communities in bulk soil samples collected in the northeast of Mexico. Bulk soil textures and chemical properties, including most nutrients, were homogeneous in these bulk soil samples. Relative abundance analysis showed similar bacterial community structures. Dominant taxonomic phyla were Proteobacteria, Firmicutes, Acidobacteria, Actinobacteria, Gemmatimonadetes and Bacteroidetes, whereas the main families were Bacillaceae, Chitinophagaceae and Rhodospirillaceae with an abundance average of BS1 (bulk soil sample), BS2 and BS3 (24.85, 19.74 and 19.71%, respectively). Alpha diversity analysis showed a high diversity (Shannon and Simpson index) and a large value of the observed species found in bulk soils samples. These results allowed establishing the previous bacterial structural community in an unused soil before sowing it with a transgenic crop for the first time.

The aim of the study was to determine the glycoproteins content (total glomalin (TG), easily extractable glomalin (EEG) and soil proteins related to glomalin (GRSP)) in soil under long-term monoculture of maize. Soil microbiological and biochemical properties, including microbial biomass and enzymatic activity were also assessed. The presence of total, easily-extractable glomalin and soil proteins related to glomalin was dependent on both the growth phase of the plant and tillage system. The highest content of glomalin was detected in the soils under maize in direct sowing and reduced tillage. The glomalin content was correlated with soil biological activity. The linear regression was observed between TG and GRSP content, but no linear relationship was found between GRSP and C_org. The principal component analysis showed the strong correlations between the parameters of soil quality and biodiversity indicators. Selected indicators of soil microbial parameters explained 52.27% biological variability in soils.

The present study investigated the impact of transgenic Bacillus thuringiensis (Bt) cotton on several aspects of arbuscular mycorrhizal (AM) fungus Funneliformis mosseae. The results showed that Bt cotton significantly inhibited spore germination and pre-symbiotic hyphal growth. The appressorium density, arbuscule frequency and colonization intensity in Bt roots were also decreased. The statistical analysis demonstrated that the transformation event resulted in the inhibition of hyphal development and colonization. The reduced interaction between AM fungi and plants could affect nutrient uptake and transportation in plant-fungus symbiosis. The mechanism might involve the direct toxicity of Bt toxins or the interference of signal perception between AM fungus and Bt cotton.

Biochar has been studied extensively in terms of its influence on soil hydrophysical properties, but only small part of results was obtained from the field experiments. In this study, the soil water content was measured in 5-10 cm depth at experimental plots which received 20 t/ha and 0 t/ha (control) of biochar amendment at the Malanta area (Slovakia). The experimental area was cultivated with maize in 2015 and spring wheat in 2016. Our field measurements show that the positive effect of biochar amendment (20 t/ha) on soil water content is strongly related to the type of the crop grown and not straightforward. Unexpectedly, during the monitoring campaign in 2015 the soil water content of the biochar-amended soil was lower than control. In 2016, negligible differences were observed in soil water contents at both experimental plots, especially during the dry spells. However, higher soil water content was measured at the plot with biochar amendment after the series of precipitation events during the physiological maturity of the spring wheat. Moreover, the biochar amendment did not increase the biomass production and yields of maize in 2015, but it significantly increased the biomass production and yields of spring wheat in 2016.

The study concerned the determination of nitrous oxide (N₂O) emissions under conventional and reduced tillage conditions. In the reduced cultivation, a soil cultivating seed drill was used for simultaneous sowing of seeds and subsurface application of fertilizer. The emission levels of the gas tested were dependent on the year of the study and the method of soil tillage, and were subject to considerable changes during the growing season. The use of reduced soil tillage significantly limited emissions of the analysed gas into the atmosphere. Depending on the year of the study, N₂O emission in the reduced tillage system was from 15% to 40% lower than in the conventional system. Low levels of easily mineralized components in soil could have been the cause of the reduction in N₂O emissions to the atmosphere.

Transpiration efficiency (TE) is an important physiological trait associated with drought tolerance of plants. Currently, little is known about the grain sorghum TE and its dynamics with the age of plants. To compare the sorghum TE at different growth stages, four studies (two in the greenhouse and two in the growth chamber) were conducted under controlled environmental conditions. Plants were grown in lid-covered boxes and harvested at six-leaf, flag leaf, grain filling and maturity stages. The mean shoot TE values were 4.47 and 4.10 kg/m³ for two greenhouse studies, and 4.85 and 4.30 kg/m³ for two growth chamber studies, respectively. The shoot TE was not different among four growth stages within each study, suggesting that sorghum plants used the same amount of water per unit of biomass production for different growing periods. Because crops grown under dryland environments often run out of water during reproductive periods, result supports the ideas that soil water availability at later growth stages is crucial to achieve the yield potential of dryland sorghum.

Three moss (Pleurosium spp., Polytrichum spp., Rhytidiadelphus spp.) and two lichen taxa (Hypogymnia physodes L., Pseudevernia furfuracea L.), were exposed for four weeks in six petrol stations, two consecutive years (2015-2016), in urban area of the Prešov city (Slovakia), to assess accumulation of selected airborne elements Cd, Co, Cu, Fe, Hg, Mn, Ni, Pb and Zn. Significantly highest (P < 0.01) ability to accumulate Zn, Ni, Co and Fe was found in Pleurosium spp.; Pseudevernia furfuracea was determined the best accumulator of Hg, whereas Rhytidiadelphus spp. was found as the least suitable for this purpose. No significant differences in heavy metal accumulation between moss and lichen taxonomic group were found. Samples of conifer (used as a moss/lichen bag holder) showed significantly lower content of heavy metals compared to mosses and lichens. Major content of heavy metals trapped in the air around petrol stations, did not originate from the petrol combustion, but predominantly from the car body, which is mechanically disrupted during fuelling.

This experimental work was undertaken to assess the effect of various fertilization regimes (CaNPK, NPK, CaPK, CaPN, CaKN and Ca) and different soil properties on growth and yield of Miscanthus plants and to check the impact of this plant on soil microbial characteristics. Field experiment was set up in 2003 on a long-term fertilization experiment, which had been established since 1923. Miscanthus giganteus response to high soil acidity and deficiency of N, P and K was investigated. Some physico-chemical and microbiological properties of soil samples were estimated and microbial characteristics of soil were conducted to investigate the number of the following microorganisms: heterotrophic bacteria, microscopic fungi, and some diazotrophic bacteria. Obtained results showed that, the highest yield of Miscanthus was obtained from the field fertilized with the CaNPK; while the lowest one was found for plants grown without nitrogen (CaPK). The high acidity of soil and small amount of phosphorus did not affect the yields in the NPK and CaKN combinations as compared with CaNPK one. The experiments showed that Miscanthus giganteus responded positively to mineral fertilization, especially with nitrogen. The rhizosphere of Miscanthus plants provides a suitable environment for the growth and development of microorganisms, in contrast to the non-rhizosphere zone.

Effects of insecticidal sprays on poppy root weevils (Stenocarus ruficornis, Stephens 1831) were assessed in small plot trials at three localities in the Czech Republic during two years (2011-2012). In addition, the effects of seed dressing were included into the assessment in one of the localities (Červený Újezd). The levels of root damage caused by the insect pest larvae (expressed as number of bore holes per root) and yield got from individual treatments were compared. Sprays applied for 18 days after the first record of poppy root weevils in trials showed the highest effects on a decrease of the levels of root damage (40% of untreated control). In general, sprays applied at the date when SATF₁₄ value exceeded 20°C showed significant effects on decreasing the levels of root damage. The highest effects were usually recorded in sprays which were applied when SATF₁₄ value exceeded 100°C.

We studied the heterogeneity of soil weed seed-bank in a rice-wheat rotation system after long-term application of different organic or non-organic fertilizers, and the effects of major nutrients on the characteristics of the weed seed-bank. The soil was sampled in the Taihu area after a 31-year long-term fertilization experiment. Weed seeds were identified and counted in the surface soil of 12 differentially treated areas using microscopic examination, and analyzed by the Simpson, Shannon, Margalef, and Pielou indexes. The long-term application of organic fertilizers could significantly reduce the density of soil weed seed-bank; non-organic fertilizers and a combination of non-organic and organic fertilizers had a significant influence on the number of species and diversity of weeds. The application of organic fertilizers improved the Simpson, Shannon and Pielou indexes of soil weed seed-bank community and stabilized the community structure. In terms of the soil nutrient system itself, the soil organic materials and total nitrogen content are the main environmental factors affecting the distribution of soil weed seed-bank.

Amaranth is a promising C4-crop. However, for a wider spread of the crop a better understanding of factors that are influencing yield formation is crucial for optimizing the plant phenotype and enhancing yield. The present study wanted to clarify the effects of assimilate sources and sinks on yield formation by artificially altering source or sink size. Field experiments were conducted in Eastern Austria during three years with three genotypes, applying source-sink manipulation treatments at mid flowering (control, 50% of inflorescence removed, 50% or 100% of leaves removed). At maturity we measured shoot, inflorescence and grain dry matter, thousand kernel mass and number of seeds per plant. An average grain yield level of about 3.5 t/ha dry matter on control plots indicated favorable growth conditions for amaranth in general. The removal of all leaves had a strong detrimental effect on all parameters, but severity of yield reduction due to defoliation differed between genotypes, ranging from -49% to -73%. Contrastingly, 50% flower reduction did not have any significant effects. Also with 50% defoliation no significant yield reduction was observed. We conclude that source strength of amaranth during flowering is more yield limiting than its sink capacity.

Timely and reliable prediction of grain yield and quality of spring barley represents a key prerequisite for effective crop management. Within this study we evaluated the relationships between yield components, grain quality, biomass production and the number of tillers in different growth stages. For this purpose, in three years (2011-2013) multifactorial field trials focused on the combined effects of cultivar, sowing density and nitrogen nutrition were conducted. Based on ANOVA it was found that the formation of grain yield was affected by individual factors in the following order of importance: year, nitrogen, cultivar and sowing rate. The final grain yield significantly correlated both with the number of tillers and dry weight of above-ground biomass per unit area. The best estimation of yield provided both parameters at early growth stage (R = 0.83** and 0.81** for number of tillers and the above-ground biomass at BBCH 25). The grain protein content was inversely related to early growth parameters (R = -0.64** and -0.41** for number of tillers and above-ground biomass at BBCH 25). Based on the comparison of relationships between the years, it can be concluded that the early growth of barley and tiller differentiation is a key parameter for the formation of yield and grain quality.

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.

A field experiment with a malting spring barley crop (2007-2009) was conducted in south-eastern Poland on Cambisols. Conventional (CST) and simplified soil tillage systems (SST) were used in combination with NPK fertilizer enriched with S and Mg. Analysis of the results showed a beneficial effect of CST and NPK fertilization with S and Mg on yield and yield structure. SST and NPK fertilization decreased grain yield by 6.6% and 6.2%. CST increased grain number per ear, grain weight per ear and plant height, while the SST decreased the value of these characteristics by 7.9, 5.7 and 5.3%. Number of ears (standardized regression coefficient b = 0.330), grain number per ear (b = 0.488) and 1000 grain weight (b = 0.360) were found to be significant for predicting grain yield. Significant correlations were found between grain yield and yield components of spring barley. Grain yield per ha was positively correlated with number of ears (r_n = 72 = 0.330), grain number per ear (r_n = 72 = 0.488), 1000 grain weight (r_n = 72 = 0.359), grain weight per ear (r_n = 72 = 0.528) and plant height (r_n = 72 = 0.246).

The experiments were conducted in four locations in Serbia: Valjevo, Kucevo, Nova Pazova and Surduk in 2012 and 2013. A working hypothesis that growing conditions would not affect the rutin content in buckwheat leaves was set up. The content of rutin in leaves of buckwheat was determined by the HPLC/DAD technique, using the external standard calibration method. Out of the basic biometric parameters, average value, variance, and the variation coefficient were estimated. Results were processed by the analysis of variance for the factorial experiment. The analysis of variance showed existence of significant differences in the rutin content, over locations, but only in the first year of testing. The average content of rutin in the first and the second year was 3.30% and 2.61%, respectively, and in both years of testing it amounted on average to 2.82%. The variation in the rutin content was larger in the second year of testing. On the other hand, this variation was lower in the first year (5.3-29.0%) in comparison to the second year (16.2-28.6%). Relatively lower rutin contents were recorded in samples collected at lower-altitude locations.

Among Meliaceae derivatives, neem cake is usually used as a fertilizer; however its origin and industrial processing are often unknown, so that its effect on soil fertility is not predictable. In this study, the effect of soil incorporation of 6 commercial neem cakes and leaves of Melia azedarach L. on nitrogen (N) and carbon (C) dynamics was investigated in a 118-day laboratory incubation experiment. Neem cake at a rate of 8 g/kg of soil and melia leaves at 16 g/kg were incorporated into the soil and their net N and C mineralisation were evaluated 2 h after application and at day 1, 2, 6, 12, 26, 54 and 118, by analysing a 50-g soil sample placed in 250 glass jars. The apparent net N mineralisation was well predicted by N concentration and C/N ratio of derivatives. The derivatives with a C/N ratio < 24 caused a net N mineralisation, whereas those with a C/N ratio ≥ 24 caused net N immobilisation. C mineralisation ranged between 15% and 25% and was not related to chemical composition of the derivative. Neem cake with a C/N ratio < 24 can be used to add N, while neem cake with a C/N ratio > 24 can be used to reduce soil mineral N.

Paddy rice is one of the most important cereal crops in China. Nitrogen (N) is closely related to crops production by influencing the photosynthetic efficiency of paddy rice. In this study, laser-induced fluorescence (LIF) technology with the help of principal component analysis (PCA) and back-propagation neural network (BPNN) is proposed to monitor leaf N content (LNC) of paddy rice. The PCA is utilized to extract the characteristic variables of LIF spectra by analysing the major attributes. The results showed that the first three principal components (PCs) can explain 95.76% and 93.53% of the total variance contained in the fluorescence spectra for tillering stage and shooting stage, respectively. Then, BPNN was utilized to inverse the LNC on the basis of the first three PCs as input variables and can obtain the satisfactory inversion results (R² of tillering stage and shooting stage are 0.952 and 0.931, respectively; residual main range from -0.2 to 0.2 mg/g). The experimental results demonstrated that LIF technique combined with multivariate analysis will be a useful method for monitoring the LNC of paddy rice, which can provide consultations for the decision-making of peasants in their N fertilization strategies.

Festuca ovina L. is an important ornamental species used in urban landscapes and pastures reclamation. However, low resistance of this species to salt stress has hindered its extended application in low-water and salty regions. To study the effects of calcium on reducing salt stress injuries in seed germination and early growth of this species, a factorial experiment based on completely randomized design with three replications was conducted. The salt levels included NaCl solutions (5, 10, 15 and 20 dS/m). Calcium source was CaCl₂ with concentrations of 0, 10, 20 and 30 mmol₊/L. Germination percentage and mean germination time were significantly affected by interaction of salinity and calcium. As salinity increased, mean germination time increased. However, germination percentage, shootlet length, rootlet length, shootlet fresh and dry weight, rootlet fresh and dry weight and seed vigour index decreased following the increasing salinity. Concentrations of 10 and 20 mmol₊/L CaCl₂ had significant effects on reducing salt injuries on seed germination of Festuca ovina. This finding was even prominent in higher salinity levels of 15 and 20 dS/m. Therefore, to facilitate using this species in urban landscapes or in pastures, pre-treatment of the seeds using 10 and 20 mmol₊/L CaCl₂ is recommended.

The purpose of the study has been to determine the effect of soil contamination with copper on the modification of microbial number and spring barley yield and to assess whether spores of actinomycete Streptomyces odorifer and Streptomyces viridis were used for detoxification of copper polluted soils. The tests were performed in a pot experiment, which was conducted on two types of soil: Eutric Cambisol soil derived from light loamy sand and Eutric Cambisol soil derived from light loam. The results showed that number of all analysed microorganisms was significantly negatively correlated with a degree of soil contamination by copper, but positively correlated with the yield of spring barley. In general, the adverse impact of copper on the development of oligotrophic bacteria and their spores, eutrophic bacteria and their spores as well as actinomycetes and fungi was much weaker in more compact (light loam) than lighter (light loamy sand) soil. Copper had a strong toxic effect on spring barley and significantly inhibits the growth and development of the plants. An inoculum containing spores of Streptomyces viridis and Streptomyces odorifer did not alleviate the negative response of spring barley to copper contamination of soil, although it had positive influence on the growth of some microorganisms.

The effect of mineral nitrogen (N) nutrition on seed production and acquisition of ¹⁵N from fertilizers by components of cereal-pea mixtures was investigated. Yields of wheat-pea and oats-pea mixtures raised together with the increase of cereals percentage in the pot, and higher seed yields of mixture with barley was affected by a larger share of pea plants. The percentage of nitrogen derived from fertilizers was significantly higher in cereals as compared with pea. Pea accumulated the greatest quantity of nitrogen from fertilizers in straw and roots, and cereals translocated ¹⁵N mainly to ears - grain and glumes with rachis. The percentage of ¹⁵N in seeds of pea amounted to 15% on the average, and in grain of cereals - 54% to 60% of the total N taken up.