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The object of our study is soil fertilized with a variety of compost produced from unsorted municipal waste maturing in heaps for different lengths of time, and with green waste compost. Municipal waste composts were applied at rates of 10 and 30 g·kg-1 soil, whereas green waste compost was introduced to soil as 10 g·kg-1 soil. Processes that take place during compost maturation have resulted in an increased concentration f polycyclic aromatic hydrocarbons. More PAHs were determined in municipal waste composts than in green waste compost. Fertilization of soil with municipal waste composts increased the content of PAHs in soil, but in most cases the natural concentration of these compounds was not exceeded. However, the total PAHs more than 200 μg·kg-1 d.m. soil, which is above the natural content, were observed in the objects where the highest rates of one- and three-month-old composts were applied. In the objects fertilized with green waste compost, total PAHs (as well as the levels of particular compounds) were close to the values recorded for the control object.
Up till now, no critical contents have been elaborated which permit to evaluate the correct microelement nutrition on the basis of chrysanthemum stock plant leaves analysis. Experiments were carried out to determine the content of iron, zinc and copper in the leaves of chrysanthemum motherplants by studying 16 cultivars in 2000 and 13 cultivars in 2001. Analyses were carried out at 4 terms (from: February to May). The values characterizing the content of the particular components in the leaves of each cultivar of chrysanthemum were statistically elaborated. Standard deviation for the cultivars and variation coefficient for the whole population in the given year were calculated. The usability of guide values utilized for traditional methods of chrysanthemum growing in diagnostics of plant nutrition were critically evaluated. New standard ranges of the content of iron, zinc and copper in chrysanthemum motherplant leaves were elaborated.
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Haploidy in early bovine embryos produced in vitro

88%
Early bovine embryos (two - to sixteen blastomeres) produced in vitro were cytogenetically analysed to determine the incidence of haploidy. Follicular oocytes were matured in vitro and inseminated with sperm prepared using the swim up method. After 2-3 days of culture, chromosome slides were prepared according to the air-drying technique and stained with Giemsa. Altogether 202 embryos produced metaphase spreads. Of these 4.5% were pure haploid embryos and 5.5% displayed a haploid cell line within mosaic embryos (n/2n and n/3n). The occurrence of haploid embryos observed in this study was compared to results of other studies and a possible origin of haploidy was discussed.
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Wartosc nawozowa kompostu z osadu sciekowego

76%
The fertilization value of composted sewage sludge was estimated on the basis of pot experiments during three following vegetation periods with buckwheat sown twice (1998), oat and maize (1999) and oat again (2000). The availability of nitrogen, phosphorus, magnesium and zinc for tested plants was determined. Tested manure was obtained after 8 months of composting of the mixture of sewage sludge with 20% of sawdust and 3% of CaO. The compost moisture was 69%. The following contents of nutrients was found (g·kg⁻¹): N - 21.0, P - 5.47, K - 1.11, Mg - 3.22 and Zn - 1 204 mg·kg⁻¹. The C : N ratio was 17.4. Compost was applied in the first year of experiment in two doses 150 or 300 g per 6 kg of poor sandy loam acid soil. The application of compost to the soil resulted with a noticeable increase of the yield of dry matter of tested plants due to the privation of nutrients under the tested conditions. The uptake of nutrients noticeably increased, predominantly of phosphorus and magnesium. Total uptake of nitrogen, phosphorus and magnesium was at the level of 16.4%, 32.5% and 45% respectively, during 3 years of experiment with the incorporated lower dose of compost. The incorporation of a high dose of zinc with compost at both doses did not result with a significant increase of its uptake by plants due to the decrease of acidity. Fertilization of the tested soil with composted sewage sludge positively affects the physico-chemical properties of soil. The cation exchange capacity and the amount of available phosphorus and zinc were found to be improved and as the soil acidity was noticeable lower.
The study was conducted over the years 2004–2006 in experimental plots located in Bałcyny. A multi-purpose, late potato cultivar, Jasia, was grown. The experimental factors were as follows: I – mineral fertilization levels: A (N – 80 kg ha⁻¹, P – 80 kg ha⁻¹, K – 120 kg ha⁻¹), B (N – 120 kg ha⁻¹, P – 144 kg ha⁻¹, K – 156 kg ha⁻¹), II – foliar fertilization: 1 (Basfoliar 12-4-6 – 8 dm³ ha⁻¹), 2 (ADOB Mn – 4 dm³ ha⁻¹), 3 (Solubor DF – 2 dm³ ha⁻¹), 4 (ADOB Mn – 2 dm³ ha⁻¹ + Basfoliar 12-4-6 – 4 dm³ ha⁻¹), 5 (ADOB Mn – 2 dm³ ha⁻¹ + Solubor DF – 1 dm³ ha⁻¹), 6 (Basfoliar 12-4-6 – 4 dm³ ha⁻¹ + Solubor DF – 1 dm³ ha⁻¹), 7 (Basfoliar 12-4-6 – 2.7 dm³ ha⁻¹+ADOBMn – 1.3 dm³ ha⁻¹+SoluborDF – 0.7 dm³ ha⁻¹), 8 (control treatment without foliar fertilization). The health status of potato tubers was studied after five-month storage. The rates of tuber infection by Streptomyces scabies and Rhizoctonia solani were estimated on 100 tubers selected randomly of particular treatments, according to a nine-point scale, and were presented as a percentage infection index. The symptoms of soft rot (Pectobacterium carotovorum subsp. carotovorum), late blight (Phytophthora infestans) and dry rot (Fusarium spp.) were evaluated in 5 kg samples for each treatment. The results were expressed as a percentage of the mass of infected tubers. Foliar fertilization and the levels of mineral fertilization NPK did not affect the severity of common scab symptoms. Significantly higher rates of infection by R. solani were observed in tubers from the control treatment without foliar fertilization and from the treatment with a lower level of mineral fertilization (A). The symptoms of soft rot (4.6% of the mass of infected tubers) and late blight (1.3%) were strongest in 2006, while the symptoms of dry rot (2.7%) – in 2005. The severity of diseases caused by the above pathogens was greater in tubers grown in plots with a higher level of mineral fertilization (B) – N 120 kg ha⁻¹, P 144 kg ha⁻¹, K 156 kg ha⁻¹ (1.3 to 4.1% of the mass of infected tubers) than in tubers grown in plots with a lower level of mineral fertilization (A) –N80 kg ha⁻¹, P 80 kg ha⁻¹, K 120 kg ha⁻¹, (0.8 to 3%). The combined application of foliar fertilizers reduced the percentage mass of tubers infected by P. carotovorum subsp. carotovorum and P. infestans to the highest degree.
The aim of the present research was to evaluate whether or not, and to what extent, exclusive mineral fertilisation affects the content of water-soluble ions determining the soil salinity. The soil was sampled from the arable layer of a multi-year field experiment carried out in 1974-2007. The research involved differentiated nitrogen fertilisation (factor I, n=3) and potassium fertilisation (factor II, n=4). The content of water-soluble ions was defined in water extract, in the soil to water ratio of 1:5; cations K+, Na+, Ca2+ were determined with the method of emission spectrometry and Mg2+ – with atomic absorption. Anions were analysed with the argentometric (Cl-) and nephelometric (SO4 2-) methods. In addition, electrolytic conductivity (R) was tested with the conductometric method, based on which the salt concentration in the solution (C) and the ionic strength (I) were calculated. The present results were statistically verified. The prolonged application of intensive nitrogen and potassium fertilisation (32 years) significantly differentiated the content of cations: K+, Na+, Ca2+ and Mg2+ as well as anions: Cl- and SO4 2- in soil solution. The contents of K+, Na+, Ca2+, Mg2+ in the soil solutions differed and fell within the range of (mean value) 0.136-0.507 (0.281) K+, 0.398-0.555 (0.472) Na+, 1-2.192 (1.350) Ca2+ and 0.211- 0.365 (0.272) Mg2+ mmol(+)⋅kg-1. The highest nitrogen dose significantly limited the concentration of SO4 2- in the soil solution, while the different doses of potassium did not result in such significant changes in the concentration of the above ions. The content of chlorine ions in the soil solution did not depend significantly on differentiated nitrogen and potassium fertilisation. No effect of the long-term mineral fertilisation on soil salinity was noted.
Improving Nitrogen Use Efficiency (NUE) in crops of winter wheat is of interest in Poland, due to their significant share in the sown area. The aim of this study was, therefore, to determine the relationships between grain (Yd) and N yields (Yn), NUE, Water Use Efficiency (WUE) depending on N rates (F) and actual potential evapotranspiration (APET). The study used the results of field experiments, conducted in the years 2003–2013 in two locations in Poland. In the experiments, wheat was fertilized with doses of 40, 80, 120, 160 and 200 kg N/ha under the fertilization with P, K, Mg and Ca. It was found that the dose range of 80 ± 40 kg N/ha allowed to obtain Yd of 5.34 ± 1.43 t/ha and NUE values of 116 ± 17%, which brought the risk of soil N mining. Increasing N doses (160 ± 40 kg/ha) increased Yd (6.08 ± 0.71 t/ha) and allowed for obtaining the desired values of NUE (73 ± 5%), Yn (119 ± 18 kg/ha) and N surplus (43 ± 13 kg/ha). The performed statistical analysis showed that Yd, Yn and WUE had grown with increasing doses of N under the influence of water shortages in the range of APET less than 398 mm. Under these conditions positive interaction between Yd, Yn, WUE depending on F and APET has been demonstrated. Only for a dose of 200 kg N/ha were found negative interactions between Yd, WUE on F and APET. NUE decreased with increasing N doses. The relationship between NUE and WUE was positive but specific for N doses due to the statistically significant interaction of F×WUE. The maximum value of WUE obtained in the experiments was 26 kg grain/ha/mm. In the absence of limiting factors WUE increased linearly together with growing NUE up to the value of 93.9% and then linearly decreased. In the range of the desired NUE values (50–90%), WUE values were between 16,4–23,5 kg grain/ha/mm.
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