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The aim of the study was to determine the influence of the process of low-temperature transformation and the addition of plant material to sewage sludge diversifying the content of mobile forms of heavy metals and their ecotoxicity. The experimental design included: sewage sludge + rape straw, sewage sludge + wheat straw, sewage sludge + sawdust, sewage sludge + bark and sewage sludge with no addition. The mixtures were subjected to thermal transformation in a chamber furnace, under conditions without air. The procedure consisted of two stages: the first stage (130 °C for 40 min) focused on drying the material, whereas in the second stage (200 °C for 30 min) proper thermal transformation of materials took place. Thermal transformation of the materials, caused an increase in total contents of heavy metals in comparison to the material before transformation. From among elements, the cadmium content changed the most in materials after thermal transformation. As a result of thermal transformation, the content of water soluble form of the heavy metals decreased significantly in all the prepared mixtures. Low toxicity of the extracts from materials for Vibrio fischeri and Lepidium sativum was found in the research, regardless of transformation process. L. sativum showed higher sensitivity to heavy metals occurring in the studied extracts from materials than V. fischeri , evidence of which are the positive significant correlations between the content of metals and the inhibition of root growth of L. sativum . [ABSTRACT FROM AUTHOR]

• PGRs changed plant growth dynamics. • Trinexapac-ethyl, paclobutrazol, flurprimidol, mefluidide and ethephon reduced plant growth. • Gibberellic acid resulted in higher plant growth. • PGRs resulted in reduced mechanical strength parameters. • Mechanical traits depends on rate of paclobutrazol, flurprimidol and gibberellic acid. Plant growth regulators (PGRs) are widely used on sport turfgrass to reduce mowing frequency and inhibit seedhead formation. However, PGRs may also affect turf colour, density and wear tolerance. The objective of this study was to examine the effects of plant growth regulators on the mechanical properties of leaves of perennial ryegrass (Lolium perenne L.). A pot trial was conducted in three seasons in 2016-2018. Three cultivars were tested, 'Barlicum', 'Vulcanus', and 'Info'. Six different PGRs, trinexapac-ethyl, paclobutrazol, flurprimidol, mefluidide, ethephon and gibberellic acid, were applied at five different rates. An untreated control turfgrass was also tested for each cultivar. The turfgrass height was measured using a falling plate metre. The biomechanical parameters, i.e., strain-at-break, stress-at-break, modulus of elasticity and work-to-break, were determined using a tensile testing machine. All tested PGRs significantly changed plant growth dynamics. Trinexapac-ethyl, paclobutrazol, flurprimidol, mefluidide and ethephon application reduced plant growth. Gibberellic acid resulted in higher plant growth. This effect was usually observed at 7, 14 and 21 days after PGR application. Perennial ryegrass leaves under tensile stress exhibited a characteristic behaviour with a nearly linear initial period followed by a decrease in the stress rate under a constant strain rate. All PGRs resulted in reduced mechanical strength parameters, namely, stress-at-break and modulus of elasticity. Gibberellic acid also resulted in lower strain-at-break. The work-to-break parameter was affected by all PGRs except ethephon. The PGRs application rate significantly affected certain mechanical parameters only when paclobutrazol, flurprimidol and gibberellic acid were used. [ABSTRACT FROM AUTHOR]

Compost extracts with the addition of polymers obtained from thermoplastic corn starch and polyethylene are novel organic amendments, which can be typically applied to suppress soil-borne diseases. Considering the diversity of biologically active substances, including those growth-promoting and stabilizing various pathogens contained in extracts, composts have a large potential to successfully replace the massively used pesticides. The effect of various concentrations of water compost extracts with the addition of polymers obtained from thermoplastic corn starch and polyethylene on the linear growth, biomass, and sporulation of the following polyphagous fungi was assessed under in situ and in vitro conditions: Fusarium culmorum (W.G. Smith), Fusarium graminearum Schwabe, Sclerotinia sclerotiorum (Lib.) de Bary, Rhizoctonia solani Kühn, Alternaria alternata (Fr.) Keissler. The studies revealed that the fungistatic activity was determined by the kind and concentration of compost extract added to the medium, as well as by the fungus kind. The analyzed compost extracts blocked the linear growth of the tested fungi on average by 22%, biomass increment by 51%, and sporulation by 57%. F . culmorum and S . sclerotiorum proved to be the most sensitive to the tested compost extracts. It was found that the extract from compost with the addition of polymer with the highest share of polyethylene blocked the sporulation of F . culmorum by 87% and F . graminearum by 92%. In turn, composts with the addition of polymers with the highest share of a biocomponent weakened the fungistatic activity of composts. The authors demonstrated that the addition of microbiological inoculum to one of the composts enhanced the fungistatic activity with respect to S . sclerotiorum , F . graminearum , and F . culmorum . The obtained results can be used to better understand the growth-promoting and suppression effects of compost extracts with polymer addition, help to enhance crop production, and constitute a paradigm shift towards the development of the next generation of compost with applications in a range of new fields. [ABSTRACT FROM AUTHOR]

• Effect of PGRs was in the wavelength range from 540 to 650 nm. • Gibberellic Acid resulted in lighter leaves with higher yellow hue. • Paclobutrazol and Trinexapac Ethyl had a beneficial influence on colour and turf quality. • Flurprimidol and Mefluidide did not change turfgrass colour and quality. Plant growth regulators (PGRs) are used on turfgrass to slow vertical growth and reduce mowing intensity. However, turfgrasses sometimes exhibit some leaf discolouration after PGR applications. The objective of this study was to determine the effect of different rates of PGRs on turfgrass quality with a special focus on colour characteristics. Three cultivars of perennial ryegrass (Lolium perenne L.) were used in an experiment. Six PGRs were used, namely, Trinexapac Ethyl, Paclobutrazol, Flurprimidol, Mefluidide, Ethephon and Gibberellic Acid, at five different rates. A control without the addition of PGRs was also tested simultaneously. The measurement of leaf colour was performed using a portable spectrophotometer and is presented in CIE Lab colour space. The turfgrass quality was assessed by a visual score. The results showed that the turfgrass quality was significantly different regarding the perennial ryegrass cultivar, treated with different PGRs rates. The changes owing to different PGRs rates appeared in the wavelengths ranging from 540 to 650 nm. PGRs application significantly affected L , b and a colour components. Gibberellic Acid application resulted lighter leaves with higher yellow hue and in a lower score of overall appearance and turf colour assessment. Paclobutrazol and Trinexapac Ethyl, had a beneficial influence on colour characteristics and turf quality. Flurprimidol and Melfuidide had no effect on turfgrass colour and quality after PGR treatment. The changes in colour of turf of perennial ryegrass correlated with PGR rates. Higher rates resulted in increased intensity of discolouration. The results of the spectrophotometric analysis of leaf colour corresponded with visual turf colour assessment. However, visually scored turfgrass did not show differences between PGR rates. [ABSTRACT FROM AUTHOR]

• Optimum fertilizers rate and frequency was investigated. • Fertigation parameters affected nutrients content in leachate. • Fertigation parameters influence on colour and turf quality. • Optimal fertigation parameters were of 60 kg N ha−1 and fertigation interval of 4.4 days. The main aim of turfgrass fertilization is to maintain high turf quality and obtain proper turf colour. Fertigation has been recognized as the best fertilization method for proper turfgrass nutrition and for minimizing nitrogen leaching. The aim of this study was to determine the optimum fertilizer rate and frequency for obtaining high-quality turfgrass and minimizing nutrient losses using a fertigation system. Lysimeter experiment was conducted on perennial ryegrass and Kentucky bluegrass mixture in 2016-2018. Three different fertigation rate treatments were applied: 60, 120, and 240 kg N ha−1 (NPK). Fertigation was applied at three intervals: 2, 4 and 8 days between fertigation (DBF). A control treatment with granular fertilizers (CTR) was also applied. The following turfgrass parameters were scored: leaf texture, overall appearance, turf cover and turfgrass colour. Additionally, colour was measured using a spectrophotometer. The colour parameters were expressed using the CIELAB colour system. Leached water samples were taken every two weeks during the vegetation period. The contents of the available forms of selected macro- and microelements (N, P, K, Mg, Ca, Na, Zn, Cu, Mn and Fe) were determined. The fertigation parameters, nutrient rate and interval between fertigation, significantly affected the contents in leachate of most nutrients and metals, except those of N-NH 4 , Na and Zn. Fertigation resulted in significantly lower N-NO 3 losses in comparison with those under CTR. Higher rates of nutrients in fertigation solution resulted in increased N-NO 3 content in leachate. The same effect was observed for P, Mg, K, Ca and Cu. The fertigation interval only affected P losses. The lowest P content in leachate was observed in the 2DBF treatment, and the P content in leachate increased as the intervals increased. The fertigation interval did not affect the leaching of any other nutrient. However, a significant difference in leachate content was observed between the CTR with granular fertilizers and fertigation. This effect was observed for N-NO 3 , K, Ca, Mn and Cu. A significantly higher content of all these nutrients was observed in leachate from the CTR treatment than in that from the fertigation treatments. Fertigation resulted in darker grass leaves in comparison with those under CTR. Higher fertigation rates resulted in darker leaves with higher green hue content than those at lower rates. There were no differences in colour hue in turfgrass fertigated at different time intervals. Turfgrass quality was affected by the fertigation rate and interval. This effect was significant for overall appearance, turf colour and leaf texture, but not for turf cover. The highest mean quality score was obtained at 240NPK, and the lowest was obtained at 60NPK. The optimal fertigation parameters for reduced nutrient losses and high turfgrass quality were calculated to be the 60NPK fertigation level at a fertigation interval of 4.4 days. [ABSTRACT FROM AUTHOR]

Highlights: [•] The salt concentration of 150mM limits Miscanthus growth. [•] The salt tolerance of Miscanthus depends strongly on the initial FW of rhizomes. [•] The changes FW and DW of roots and leaves most reflect salt response of Miscanthus. [•] High accumulation of K and proline in the leaves decide Miscanthus salt tolerance. [ABSTRACT FROM AUTHOR]