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New studies on the relationship between physiological phosphorus concentration and protein content were performed, involving well-characterised research material: elements of 36 carcasses of pigs differentiated in respect of gender, post-slaughter weight (PSW) and meatiness measured as the lean meat percentage (LMP), determined on the ground of dissection. The contents of total phosphorus (PC), crude protein (BC), collagen (CC) and muscular protein (BM = BC – CC) in meat were determined. It was found that determination of crude protein alone was not sufficient for prediction of natural phosphorus content in pork meat and its products. Satisfactory estimation of phosphorus content in pork meat based on crude protein and collagen content was obtained. Influence of carcass meatiness and post-slaughter weight of pigs on phosphorus content in meat was demonstrated and considered in the equation of estimating phosphorus content in meat. No effect of pig gender on phosphorus content in meat was found.
The objective of the study was to investigate the impact of sulphur application on the content (g kg-1) and uptake (kg ha-1) of phosphorus and potassium with the yield of potato tubers. In 2004-2006, a field experiment on potato was conducted, in which S was applied in different forms (elemental and K2SO4) and doses (0, 25 and 50 kg ha-1). The content and uptake of P and K in the dry mass of potato tubers was significantly increased by sulphur. The application of sulphur increased the P content and uptake irrespective of the S dose, but elemental S proved more effective. The K content was the highest when sulphate was applied at 50 kg S ha-1. The K uptake by tubers was significantly increased by both of the applied doses versus the control plots. The tuber yield depended substantially on the rate of S fertilizer. Sulphur applied as sulphate increased the content of SO4-S in the soil. The application of elemental S in a dose of 50 kg ha-1 decreased the soil pH. The soil content of total C was dependent on each dose and form of the applied sulphur. The content of SO4-S and total C in the soil positively correlated with the P content and uptake by potato tubers. A negative correlation was found between the pH value and content and uptake of P by potato tubers. No correlation was found between K and soil parameters, but a positive correlation was found between the P and K uptake by tubers and between the P and K uptake versus tuber yield.
In a 3-year experiment, the effect of catch crop management [catch crop incorporated in autumn (A) or mulched (B) vs plots without a catch crop (C)] on soil acid (PAC) and alkaline (PAL) phosphatase activities as well as on the available phosphorus content (PAVAIL) were investigated on typical Alfisol. The catch crops were sown at the beginning of August and ploughed in the autumn in 2008, 2009, and 2010, or left as mulch during the winter. Soil samples were taken four times a year from spring barley plots that were grown in 2009, 2010, and 2011. Generally, catch crop treatment significantly influenced the enzymatic activity as compared to the control. The PAC activity was significantly greater with a mulched catch crop than in a ploughed one only in I and II sampling dates, whereas the PAL activity was not influenced by the method and time of field pea management. The time of sampling significantly influenced the PAL activity in 2011 and the PAC activity in 2009 and 2011.
The subject of the work was the assessment of the effect of variable content of total phosphorus and collagen in a model product on its rheological characteristics. The trial material was formed by 5 variants of model mortadella made of lean pork shoulder (40-60%), pork stomachs (10-30%), neck pork fat in cubes (20%) and 10% addition of water-fat-protein emulsion (5/5/1). The following factors were determined: water, total protein, fat, NaCl, total phosphorus and collagen contents. The so-called invariables were calculated, i.e. content ratios of: water to protein (Feder’s number), fat to protein, phosphorus to protein and collagen to protein. The rheological properties of mortadella were tested with the CASRA method. The growing share of shoulder of higher protein content in the recipe resulted in an increase in total phosphorus content in the product and it led to strengthening of its structure and improvement of its consistency, which was shown in the linear increase in plasticity (P) and fall of product elasticity (E) and fluidity (F). The growing share of pork stomachs resulted in weakening of the structure and worsening of the product consistency, as shown by decrease in plasticity (P) and increase in elasticity (E) and fluidity (F).
In this paper the results of studies on three different forms of phosphorus – total, organic and inorganic – in soils of the Chornohora massif (Eastern Carpathians, Ukraine), depending on altitude, have been presented. The studied gleyed acid brown soils are situated in the belt of alpine meadows (1760 and 2057 m a.s.l.) and in the forest layer (1020 and 1120 m a.s.l.).
In 2002-2004, a study was carried out, based on a field experiment set up on soil of very good rye complex. The experiment was designed as randomized sub-blocks with three replications. Two methods of soil tillage, conventional and simplified tillage, and seven weeding methods such as application of the following herbicides 1) control object – without herbicides, 2) Plateen 41,5 WG , 3) Plateen 41,5 WG + Fusilade Forte 150 EC, 4) Plateen 41,5 WG + Fusilade Forte 150 EC + adjuvant Atpolan 80 EC, 5) Barox 460 SL, 6) Barox 460 SL + Fusilade Forte 150 EC, 7) Barox 460 SL + Fusilade Forte 150 EC + adjuvant Atpolan 80 EC), constituted experimental factors. Phosphorus content in the tubers of cultivar Wiking potato was determined by colorimetry and calcium was tested by the atomic absorption spectrophotometry method (AAS). Phosphorus and calcium content and their uptake with tubers yield significantly depended on the tillage methods and weed control methods as well as weather conditions in the study years. Potato tubers from the simplified tillage cultivation had more phosphorus than tubers whose cultivation was based on the conventional tillage, in contrast to calcium, which was more abundant in tubers from the conventional method. The herbicides significantly reduced the phosphorus content and increased the calcium content compared with the control object. Phosphorus and calcium uptake by potato was significantly higher in the conventionally tilled treatments compared with the simplified method, and in the herbicide-treated plots compared with the mechanically cultivated control treatment.
Leaf functional traits are indicators of both plant community and ecosystem responses to environmental factors and can thus increase our capacity to understand ecosystem processes and community assembly due to climate change. The variation in leaf functional traits between succession stages in Horqin Sandy Land is caused by soil nutrient content and by intrinsic biological characteristic of species, but the effects are different. Leaf economic spectra were assessed for seven leaf traits of eight species from early and advanced stages of succession. Species from early succession stages are Agriophyllum squarrosum (L.) Moq., Corispermum macrocarpum Bge., Setaria viridis (L.) Beauv. and Pennisetum centrasiaticum Tzvel., and species from advanced successional stages are Chenopodium acuminatum Willd., Chloris virgate Swartz, Digitaria sanguinalis (L.) Scop. and Leymus secalinus (Georgi) Tzvel. All these species were grown in a greenhouse experiment under two contrasting nutrient supplies including high nutrient level (N , with 20 g of nutrient addition) and low nutrient level (N-, with no added nutrients). As expected, the resource uptake strategies of the species were affected by soil fertilization addition. Leaf nitrogen content (LNC), leaf phosphorus content (LPC), and photosynthetic capacity per unit leaf area (Aarea) significantly increased at high nutrient level but LPC is more dramatically changed than others leaf traits. Leaf life span (LLS) and specific leaf area (SLA) did not show similar tendency with succession stage. At the same nutrient level, LES still shows different pattern between the early and the advanced succession stages. Species from early succession stages have higher LPC and Aarea, compared to species from advanced stages. Species from early succession stage also tend to have higher SLA and higher LNC than at the advanced succession stage. The LLS did not show any clear changes with succession process. These results provide evidence that LES shift along the succession process is mainly caused by intrinsic biological characteristic of species.
A three-year field experiment was conducted in Byszwałd near Lubawa in 2000-2002. The aim of this study has been to determine the influence of increasing rates of sulphur on the dynamics of available phosphorus in soil at two horizons: 0-40 and 40-80 cm. The trial was set up on acid brown soil of the granulometric composition of heavy loamy sand. The initial soil had the following properties: pH(KCl) = 5.30, mineral nitrogen 24.0, sulphate sulphur 4.10, available phosphorus 34.5 and potassium 110.0 mg kg-1 of soil. Three levels of sulphur fertilization were applied: 40, 80 and 120 kg⋅ha-1 in the sulphate form (S-SO4) and as elementary sulphur (S-S0). During the whole duration of the field trials, the results demonstrating the effect of fertilization with different forms and rates of sulphur on the content and transfer of available phosphorus in soil were inconsistent. Only the dose of 120 kg⋅ha-1 S-SO4 caused a significant increase in the concentration of available sulphur in soil in the 0-40 and 40-80 cm layers. All the rates of elementary sulphur as well as 40 and 80 kg⋅ha-1 sulphate sulphur caused little less but an increasing tendency in the content of phosphorus in soil. The effect of elementary sulphur became apparent as late as the third year of the trials. The effect of the doses of 40 and 80 kg⋅ha-1 of sulphur on properties of soil depended on the form of sulphur, duration of the experiment.
The potential of mycorrhization of lettuce in hydroponic conditions was tested in a two-year experiment carried out in the autumn of 2011 and 2012 in an unheated foil tunnel. The experimental factors were as follows: inoculation of plants with arbuscular mycorrhizal fungi (AMF+ or AMF-), concentration of phosphorus in a nutrient solution (10 or 40 mg dm-3) and the type of substrate (rockwool or coconut coir). The inoculation of plants with arbuscular mycorrhizal fungi of the genus Glomus was performed twice, i.e. while sowing seeds and when planting lettuce plants into mats. The impact of the experimental factors on the degree of colonization of lettuce roots by AMF as well as the yield and nutritional status of plants, expressed as the content of macro- and micronutrients, was studied. The mycorrhizal frequency in roots inoculated with AMF reached 51.36%. The nutrient solution concentration of phosphorus and the type of substrate did not have any significant effect on the mycorrhizal frequency. There were no differences in the yield and content of macronutrients in lettuce leaves between plants inoculated and not inoculated with AMF (AMF+, AMF-). Likewise, there were no differences in the yield caused by different phosphorus levels in the nutrient solution or the types of substrate. Plants growing on rockwool accumulated significantly less P, Ca and Mg in comparison to plants growing on coconut coir. Regarding Ca, this effect was especially pronounced in plants receiving the nutrient solution with a higher concentration of P, i.e. 40 mg dm-3. Mycorrhiza had a significant effect on the content of Cu, Mn and Zn in lettuce leaves. Inoculated plants were characterized by a lower content of these micronutries compared to plants grown without AMF. With respect to Mn, this effect was particularly evident in plants grown on rockwool.
The purpose of this study has been to determine the effect of soil contamination with fluorine on the content of phosphorus in crops. Alongside the simulated fluorine soil pollution, substances neutralizing this xenobiotic, such as lime, charcoal and loam, were applied to soil. Depending on the sensitivity of the plants, the degree of soil pollution with fluorine was: 1) 0, 20, 40 and 60 mg F kg-1 of soil under sensitive crops, i.e. narrow-leaf lupine; 2) 0, 50, 100 and 150 mg F kg-1 of soil under moderately sensitive crops, i.e. seed lucerne; 3) 0, 100, 200 and 300 mg F kg-1 of soil under more tolerant crops, i.e. maize, winter oilseed rape, spring triticale, black radish and phacelia. The content of phosphorus varied, depending on the level of soil contamination with fluorine and substances applied to inactivate this element, as well as on the species and organ of the examined plants. An increasing degree of soil pollution with fluorine contributed to raising the phosphorus content in black radish, in aerial biomass of yellow lupine and in roots of spring triticale. Regarding the maize roots, a reverse dependence was recorded. The highest phosphorus content appeared in roots of winter oilseed rape (8.16 g P kg-1 d.m.) and black radish (7.33 g P kg-1 d.m.), while the lowest one was in roots of spring triticale (0.86 g P kg-1 d.m.). Overall, the applied neutralizing substances resulted in lower concentrations of phosphorus in the analyzed plant organs, with the most univocal influence achieved in aerial biomass of yellow lupine, in roots of narrow-leaf lupine, in aerial mass and roots of black radish and in aerial biomass from the first cut of seed lucerne. In respect of the other plants, the impact of the neutralizing substances on the content of phosphorus was also significant albeit dependent on their species.
The paper dealt with the evaluation of concentration and spatial distribution of nitrogen and phosphorus forms in dug wells in selected farms in the upper Narew River valley. The study was also aimed at assessing the influence of selected elements of a farm on quality of well water. Examinations were carried out in 8 villages in Podlasie region. Three farm dug wells were selected for examination in each village. All wells take water from the first water-carrying level. The study included well waters within the section of the Narew River from the villages Sobótka to Złotoria. The checkpoints were set in: Sobótka, Narew, Ciełuszki, Kaniuki, Zawyki, Uhowo, Topilec, and Złotoria localized along the Narew and its adjacent lands. Water samples were collected in spring, summer and autumn 2006. Ammonia, nitrates (III), nitrates (V), and phosphates were determined in water samples filtered through micropore filters (d = 0.45 μm) by means of colorimetry applying a spectrometer HACH (DR-2000). Parameters of the analytical procedures were adjusted in accordance to the Decree of Minister for Environment (2004). In total, 288 determinations in three series were made. For each of the three wells from every village, the arithmetic means of the analyzed parameters were calculated on the basis of samples collected on three dates. The assessment of underground water quality was made according to the Decree of Minister for Environment of 11 February 2004 on on surface and underground water status, screening performance, interpretation and presentation of the status of such waters. In addition, the Decree of the Minister for Health of 29 March 2007 (Rozporządzenie Ministra Zdrowia, 2007) was referred to. The results were compared to concentrations of forms of particular components (N-NH4, N-NO2, N-NO3) included in the Decree of the Minister for Environment (2004) and the Decree of the Minister for Health (2007) in order to designate water quality classes and principal chemical requirements to the well waters examined. The study revealed that the analyzed waters did not meet standards set for potable water due to exceeding permissible values for ammonia and nitrates (V) concentrations. The distance of a well from the nearest farm buildings affected ammonia concentration in well water.
Vegetation experiments were conducted in the years 2002–2004, in two specialist horticultural farms. The dynamics of nitrogen, phosphorus and potassium contents were analyzed in the index parts of selected anthurium cultivars (Anthurium cultorum Birdsey): ‘Baron’, ‘Choco’, ‘Midori’, ‘Pistache’, ‘President’ and ‘Tropical’. Plants were grown in expanded clay using drip fertigation with standard nutrient solution. Fully expanded leaves after fresh-cut flowers as the index parts for chemical analyses were collected every 2 months over the period of 3 years. A varied dynamic of nutrient contents was found in the index parts of plants. During the 3 years of studies a downward trend was recorded for nitrogen content, while an upward trend was observed for contents of phosphorus and potassium. A cultivar differentiation was shown for contents of the above mentioned nutrients and quantitative proportions between them.
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