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Number of results: 40
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Abstract

Water samples were collected at 12 oceanographic stations from six standard depths ranging from 0 to 100 and 150 m. The number of bacteria and concentration of organic components were expressed in adequate units per 1 litre of sea water and in the form of the integrated values for the whole water column under I m2 of sea of organic components were expressed in adequate units per 1 litre of sea water and in the form of the integrated values for the whole water column under 1 m2 of sea surface. Total numbers of bacteria (TC) ranged from 0.16 to 7.31 x 107/1 and 1.74 — 5.67 x 10, 2/m2 saprophytic bacteria (CFU) 0.10 — 46.85 x 103/1 and 0.62 — 27.7x 108/m2. contents of particulate organic carbon (РОС) 0.02 — 0.25 mg/1 and 3.5 — 20.0 g/m2 dissolved organic carbon (DOC) 0.07 — 3.02 mg/1 and 53.5 — 207.9 g/m2, dissolved free amino acids (DFAA) 0 — 1.8965 μmol/1 and 2.7 -151.5 mmol/m2, dissolved combined amino acids (DCAA) 0 2.9366 μmо1/1 and 16.5— 163.5 mmol/m2, particulate combined amino acids (PCAA) 0 — 3.0215 μmо1/1 and 3.7 — 249.0 mmol/m2. Total numbers of bacteria and РОС, DOC and DCAA concentrations, widely differentiated in the investigated area, were on the average much lower than the values obtaine in previous years. The saprophytic bacteria content and DFAA and PCAA concentrations were at a similar level to that in the past years. Higher TC and CFU values were observed in the areas with high concentrations of phytoioplankton to the NW of Anvers I. and around Clarence I.
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Abstract

On the basis of elemental composition, optical properties in the visible region, infrared spectra and thermal analysis (TG, DTG, DTA), humic acids of tundra soils in Spitsbergen are found to be more similar to fulvic acids than to humic acids of soils from other soil-climatic zones. The authors claim that it results from climatic conditions (low temperature, considerable humidity, alternation of freezing and thawing) and specific biochemical composition of tundra plants (predominance of plants devoid of lignin) which constitute substratum of the studied humic acids.
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Abstract

This year we are celebrating 150 anniversary of the discovery of DNA by Friedrich Miescher. His finding initiated a series of discoveries that allowed to depicts life's most famous molecule with novel features with considerable biological interest. In this article we recall the biggest mile stones of 150-year history of DNA and present the context and meaning of several key observations that have brought us closer to understanding DNA. 150 years ago, people had no idea that DNA existed, and they certainly hadn’t heard of DNA structure and sequencing. We now know that DNA is a dynamic, tortuous coil, constantly shuffling and unwinding. Today DNA is all around us, in a physical sense and in a cultural sense. It is really part of our culture. We will discuss also the little known facts, often overlooked in similar discussions. We will focus particularly on Professor Richard Altmann's from Iława, whose contribution to knowledge about nucleic acids is significant, although not well recognized so far.
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Abstract

In broiler chickens, the relationship between dietary supplementation of vitamin C and hepatic, cardiac and renal heat shock proteins (HSP60, HSP70 and HSP90), heat shock factors (HSF-1 and HSF-3) and enzymatic antioxidants requires further investigation. The current study aimed to investigate this relationship at cellular and molecular levels in a 42 days experiment. Two hundred, one-day-old broiler chicks (Ross 308) were allocated into four equal groups. Chicks in the first and third groups were thermo-neutral (TN; 22°C for 24 hours/day) and fed basal diet without or with vitamin C (1g/kg basal diet), respectively. Chicks in the second and fourth groups were heat stressed (HS; 34°C for 8 hours/day) and fed basal diet without or with vitamin C, respectively. Performance parameters were recorded throughout the experiment. Levels of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione S-transferase (GST), glutathione peroxidase (GPX), Catalase (CAT) and gene expression of heat shock proteins (HSP60, 70 and 90) and heat shock factors (HSF 1 and 3) were analyzed in liver, heart and kidney tissues of the studied groups. Heat stress induced a negative impact on performance parameters, significant reduction in activities of all examined antioxidant enzymes and a significant up-regulation in heat shock proteins and factors genes in all studied tissues. Dietary supplementation of vitamin C corrected these parameters towards the normal control values. Conclusively, dietary supplementation of the examined dose of vitamin C was efficient at ameliorating the detrimental effects of heat stress on liver, heart and kidney tissues of broilers chickens at cellular and molecular levels.
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Abstract

In the present study, the effects of 10, 20, 30 ppm hormone mixtures (indole-3-acetic acid + gibberellic acid + kinetin) with 0.1, 0.3, 0.5 and 1 ppm zinc (Zn) concentrations alone and their mixtures on the cambial activity of sour cherry (Cerasus vulgaris Miller) cuttings were investigated. Morphological and anatomical developments of the plants were observed. The leaves of the plants treated with zinc were found to be greener than the control. Plants treated with zinc faded earlier than the control. The cambial zone thickness, the cambial zone cell line, the radial and tangential lengths of the cambial zone cells decreased with increasing concentrations of zinc and increased with increasing concentrations of hormones. The radial and tangential wall widths of the cambial zone cells increased with increasing zinc concentrations and decreased with increasing hormone concentrations. As a result, in the 0.1, 0.3, 0.5 and 1 ppm Zn concentrations, the cambial zone thickness decreased by 10, 28, 50 and 65%, respectively, compared to the control. Thirty ppm hormone mixture – H.M. (indole-3-acetic acid + gibberellic acid + kinetin) increased the cambial zone thickness by 65, 15, 5% in 0.1, 0.3 and 0.5 Zn, respectively, compared to the control. It was found that plant hormones importantly improved the harmful effects of zinc on the cambial activity of the plant cuttings.
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Abstract

The research was focused on the selection of the best conditions for the lactic acid production. As the organic source diluted waste whey was used. Two facultative anaerobic bacteria strains were examined: Lactobacillus rhamnosus and Lactococcus lactis. The neeed of anaerobic conditions as well as mineral supplementation of cultivationwere investigated. It turned out that the oxidationwas not the key parameter, but cultivationmediumneeded a supplementation for higher process efficiency. Finally, Lactobacillus rhamnosus strain was selected, for which LA production was app. 45% higher than for Lc. lactis. On the other hand, Lactobacillus rhamnosus was active at higher lactose concentration, thus waste whey needed to be less diluted. Additionally, high values of product/substrate yield coefficient make the process very efficient.
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Abstract

Effects of fermented extruded rye flour supplements with Lactobacillus sakei KTU05-6 or Pediococcus pentosaceus BaltBio02 on milk production and composition, as well as ruminal parameters, were determined in Lithuanian Black & White dairy cows. Also, determination of antimicrobial activities of tested lactic acid bacteria (LAB) against a variety of pathogenic and opportunistic bacterial strains previously isolated from diseased cattle was performed. The highest antimicrobial activity was demonstrated in L. sakei against S. aureus, and in P. pentosaceus against P. aeruginosa and S. aureus. The count of LAB in the supplements after 72 h of fermentation of extruded rye flour with L. sakei and P. pentosaceus was 9.6±0.4 log10 CFU/g and 9.5±0.3 log10 CFU/g, respectively. All cows (n=60) were fed the same basal diet. The treatment differences were achieved by individually incorporating (65 d.) one of the supplements: L. sakei KTU05-6 (group B; n=20) or P. pentosaceus BaltBio02 (group C; n=20). The control group A (n=20) was on the basal diet only. A supplement fermented with L. sakei does not have a significant influence on dairy cattle milk production and rumen fluid parameters. The type of LAB used has a significant influence (p<0.0001) on microbiological parameters of the rumen (TCM, TCL, TCE). The milk yield was increased (p≤0.05) using P. pentosaceus BaltBio02 supplement, and further research is needed to identify w hat is the main mechanism of the positive action.
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Abstract

Using High Performance Liquid Chromatography, concentrations of uric acid in the surface waters of two non-glaciated catchments (Fugle and Dynamisk) on Spitsbergen were measured. Measurements of specific conductivity enabled us to perform tests on the dissolution of the carbonate rocks present in both catchments in both natural and aqueous solutions of uric acid. Samples of calcium urate were made and its water solubility determined. Given a knowledge of concentrations of uric acid, calcium ions and calcium urate solubility product, an estimate of the role of uric acid in the dissolution of carbonate rocks was possible. Uric acid increases the dissolution of carbonate rocks by c. 12.5% in case of the Fugle catchment and 7% in Dynamisk.
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Abstract

Al2Cu phase has been obtained by melting pure metals in the electric arc furnace. It has been found that the intermetallic phase undergoes selective corrosion in the H3PO4 aqueous solutions. Aluminium is dissolved, the surface becomes porous and enriched with copper. The corrosion rate equals to 371 ± 17 g·m–2·day–1 (aerated solution) and 284 ± 9 g·m–2·day–1 (deaerated solution). The surface of Al2Cu phase after selective corrosion was characterised by using electrochemical impedance spectroscopy. It was found that the surface area of the specimens increases with temperature due to higher corrosion rate and is between 2137 and 3896 cm2.
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Abstract

Eco-friendly leather processes based on the usage of natural products have become a potentially attractive issue for leather industry during the last few decades. Synthetic protective chemicals like bactericides used in most soaking process are known as hazardous substances and cause tannery effluents with high concentrations of Chemical Oxygen Demand (COD). In the present study, the effect of tannic acid on microorganisms, skin, wool and effluent were investigated in order to demonstrate the applicability of tannic acid in soaking process instead of commonly used bactericides. The bacterial load (cfu/ml), COD and Nitrogen Content (N) of the soaking effluents and Total Kjeldahl Nitrogen (TKN) content of skins and wools were investigated. Application of 0.5 and 1 wt% tannic acid concentrations was more effective than commercial bactericide, while comparable results were achieved by 0.1 and 0.3 wt% tannic acid. The application of tannic acid for soaking process resulted in lower COD and N values of effluents. The results show that tannic acid has the potential to be an alternative, eco-friendly bactericide for leather industry by reducing the pollution of leather soaking process.
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Abstract

The study evaluated the curing properties of natural silica sand moulded with 1% by weight Furotec 132 resin binder catalysed by Furocure CH Fast acid and Furocure CH Slow acid. Physical properties of this sand included an AFS number of 47.35, 4.40 % clay, 0 % magnetic components, 0.13 % moisture, and 64.5 % of the size distribution spread over three consecutive sieves (150 – 600 μm). The sand was washed repeatedly to remove all the clay and oven dried. 2 kg washed sand samples were mulled with pre-determined weights of either catalyst to give 30 %, 50 % and 70 % by weight of 20 g Furotec 132 resin which was added last. Furotec 132 resin + Furocure CH Slow acid catalyst system gives longer bench lives and strip times but the maximum compressive strength in excess of 5000 N/cm2 is attained after more than 8.5 hours curing time irrespective of the weight % of catalyst added relative to the resin. On that basis, exceeding 30 weight % Furocure CH Slow acid catalyst when sand moulding with Furotec 132 resin has neither technical nor economic justification. In comparison, the Furotec 132 resin + Furocure CH Fast acid catalyst system was only capable of producing mould specimens with maximum compressive strength above 5000 N/cm2 at 30 weight % catalyst addition rate. At 50 and 70 weight % catalyst addition rates, the mulled sand rapidly turned dark green then bluish with a significant spike in temperature to about 40 oC, far exceeding the optimum curing temperature of Furotec 132. This high temperature accelerates the curing rate but with a very low degree of resin curing which explains the low compressive strength. In fact the sand grains fail to bond and have a dry, crumbly texture implying dehydration. Thus, not more than 30 weight % Furocure CH Fast acid catalyst should be used in sand moulding.
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Abstract

Silica multichannel monoliths modified with zirconia, titania and alumina have been used as reactive cores of microreactors and studied in chemoselective reduction (MPV) of cyclohexanon/benzaldehyde with 2-butanol as a hydrogen donor. The attachment of metal oxides to the silica surface was confirmed by FT–IR spectroscopy, and dispersion of metal oxides was studied by UV–Vis spectroscopy. the catalytic activity of the lewis acid centres in both chemical processes decreased in the order zirconia > alumina > titania. This activity is in good agreement with dispersion and coordination of metal species. good stability of zirconia-grafted reactors was confirmed. high porosity of the monoliths and the presence of large meandering flow-through channels with a diameter of ca. 30 mm facilitate fluid transport and very effective mixing in the microreactors. The whole synthesis process is perfectly in line with trends of modern flow chemistry
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Abstract

The paper deals with the impact of co-firing biomass with coal in boilers on the dew point of the flue gas. Co-firing of biomass may have twofold implications on corrosion and fouling, which are the processes that determine the lowest acceptable flue gas outlet temperature and as a result, boiler efficiency. Both phenomena may be reduced by co-firing of usually low sulphur biomasses or enhanced due to increased moisture content of biomass leading to increased water dew point. The present study concerns the problem of low-temperature corrosion in utility boilers. The paper gives (in the form of diagrams and equations) a relationship between water dew point and moisture content of fuel mixture when co-firing coal and various biomasses. The regression analysis shows that despite significant differences in the characteristics of coals and these of additional fuels, which are planned for co-firing in large-scale power boilers, the water dew point can be described by a function given with the accuracy, which shall be satisfactory for engineering purposes. The discussion of the properties of biofuels indicates that the acid dew point surplus over the water dew point (Δtr = tr - twr) is not likely to exceed 10 K when co-firing biomass. The concluding remarks give recommendations for the appropriate operation of boilers in order to reduce risks associated with biomass co-combustion.
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Abstract

The possibility of producing 3-aminobenzyl alcohol and 3-aminobenzaldehyde by oxidation of 3-aminotoluene with ozone in the solution of acetic anhydrite in the presence of manganese (II) acetate, potassium bromide and sulfuric acid has been shown. The catalytic systems for regulating selectivity and depth of substrate oxidation has been developed. The catalytic system Mn(OAc)₂ – Ac₂0 – H₂SO₄ promotes the formation of alcohol (65.5%) and 3- acetylaminobenzylidendiacetate (20.1%) with the system Mn(OAc)₂ – KBr – Ac₂O – H2SO₄ increases oxidation selectivity on the methyl group to 90.8% producing mainly aldehyde (80.8%) The optimum temperature of selective oxidation of 3– aminotoluene with the ozone – air mixture (30°C) which is much lower than that of oxidation by the known methods (120°-240°C) and the optimum rations of the reagents concentrations: for alcohol synthesis – [ArCH3] : [Mn(OAc)₂] : [H₂SO₄] =1 : 0.2 : 2.5; for aldehyde synthesis –[ ArCH3]: [Mn(OAc)₂] : [KBr] aldehyde synthesis – [ArCH3] : [Mn(OAc)₂] : [KBr] : [H₂SO₄] = 1:0.2:2.5 have been determined.
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Abstract

Chemical heat pumps (CHP) use reversible exothermal and endothermal chemical reactions to increase the temperature of working fluids. In comparison to the “classical” vapour compression chemical heat pumps, CHP enables us to achieve significantly higher temperatures of a heated medium which is crucial for the potential application, e.g. for production of superheated steam. Despite the advantages presented, currently, there are no installations using CHP for lowgrade waste heat recovery available on the market. The scaling up of industrial processes is still one of the greatest challenges of process engineering. The aim of the theoretical and experimental concept study presented here was to evaluate a method of reclaiming energy from low temperature waste streams and converting it into a saturated steam of temperature from 120 to 150 ◦C, which can be useful in industry. A chemical heat pump concept, based on the dilution and concentration of phosphoric acid, was used to test the method in the laboratory scale. The heat of dilution and energy needed for water evaporation from the acid solutionwere experimentally measured. The cycle of successive processes of dilution and concentration has been experimentally confirmed. A theoretical model of the chemical heat pump was tested and coefficient of performance measured.
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Abstract

The compost derived from cellulosic material coming from the Public Utility Company in Zabrze (Poland) was investigated for its capability for adsorbing acid dyes from aqueous solution at various concentrations of the dyes and the compost dosages. Four acid dyes were investigated: Acid Red 18 (AR-18), Acid Blue 9 (AB-9), Acid Green 16 (AG-16) and Acid Black 1 (ABk-1). The adsorption isotherms were determined by comparing the experimental data with the isotherm models (Freundlich, Langmuir and Dubinin–Radushkevich models). The sorption capacity of the compost depended on the initial concentrations of dyes in the solution, compost dosage, and on the structure of dyes. The maximum sorption capacities of the compost for adsorbing particular dyes may be ordered as follows: ABk-1 > AG-16 > AB-9 > AR-18. The amounts of bound and the percentages of removed acid dyes from effluent depended on the adsorbent dosage. The growth of the dye removal percentages with growing adsorbent mass may be attributed to the growth of the adsorbent uptake surface with growth of the adsorbent mass. The dyes were bound onto the surface of compost through the electrostatic interaction between the surface (negatively charged at pH > pHPZC) and the dye cations (AG-16), and/or through the hydrogen bond between the functional groups of the humic matter in compost (–OH, –COOH) and the functional surface groups of AR-18, AB-9 and ABk-1 dyes (–OH, –NH2 ). At the experiment conditions, the Freundlich and Dubinin-Raduskevich adsorption isotherm models fitted the equilibrium data very well (much better than the Langmuir one). The values of 1/n in the Freundlich equation and E in the Dubinin-Raduskevich one indicate the favourable adsorption. The studied compost may be used as a low-cost sorbent for the removal of acid dyes from wastewater released by textile industries. However, elevated values of chemical oxygen demand (COD) in the final solutions may enhance the solubility of humic compounds.
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Abstract

A ceria loaded carbon nanotubes (CeO2/CNTs) nanocomposites photocatalyst was prepared by chemical precipitation, and the preparation conditions were optimized using an orthogonal experiment method. HR-TEM, XRD, UV-Vis/DRS, TGA and XPS were used to characterize the photocatalyst. Nitrogen adsorption-desorption was employed to determine the BET specific surface area. The results indicated that the photocatalyst has no obvious impurities. CeO2 was dispersed on the carbon nanotubes with a good loading effect and high loading efficiency without agglomeration. The catalyst exhibits a strong ability to absorb light in the ultraviolet region and some ability to absorb light in the visible light region. The CeO2/CNTs nanocomposites photocatalyst was used to degrade azo dye Acid Orange 7 (40 mg/L). The optical decolorization rate was 66.58% after xenon lamp irradiation for 4 h, which is better than that of commercial CeO2 (43.13%). The results suggested that CeO2 loading on CNTs not only enhanced the optical decolorization rate but also accelerated the separation of CeO2/CNTs and water.
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Abstract

The paper presents the research results for the soils sampled from the area located in the eastern part of the Chodzieskie Lakes, between the Middle Noteć River Valley and the Wełna River Valley, the right tributary of the Warta River. The research involved 7 soil samples from the surface horizons, allocated to the cultivation of various plant species (cereals and vegetable crops). The following were determined in the soil material: the content of phytoavailable forms of selected heavy metals Zn, Cu, Pb, Ni, Fe and Mn, active and available to plants phosphorus against the activity of selected oxydo-reduction and hydrolytic enzymes. The soil under the vegetable crops showed a very high richness in phosphorus available to plants, which must have been related to an intensive fertilisation. There were identified relatively low contents of the available forms of the heavy metals investigated, the fact that points to their natural content in soil, which triggered the inhibition of neither the oxydo-reduction nor hydrolytic enzymes.
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Abstract

We examined whether allelochemical stress leads to increased lipoxygenase activity in roots of sweet maize (Zea mays L. ssp. saccharata), pea (Pisum sativum L.) and radish (Raphanus sativum L. var. radicula). The lipoxygenase activity of soluble and membrane-bound fractions was assessed in roots after exposure to ferulic and p-coumaric acids. Lipid peroxidation and membrane injury were determined as indicators of stress. Increased lipoxygenase activity of both studied fractions was followed by lipid peroxidation and plasma membrane injury. The results suggest the key role of lipoxygenase in plasma membrane injury during allelochemical stress caused by administration of hydroxycinnamic acids.
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Abstract

Petiole bending in detached leaves of Bryophyllum calycinum was intensively investigated in relation to polar auxin transport in petioles. When detached leaves were placed leaf blade face down, clear petiole bending was observed. On the other hand, no petiole bending was found when detached leaves were placed leaf blade face up. Indole-3-acetic acid (IAA) exogenously applied to petioles was significantly effective to induce and/or stimulate petiole bending when detached leaves were placed leaf blade face down. To clarify the mechanisms of petiole bending in detached leaves of B. calycinum when they were placed leaf blade face down, the effects of application of IAA, ethephon which is an ethylene releasing compound, inhibitors of polar auxin transport such as 2,3,5-tiiodobenzoic acid (TIBA), N-1-naphthylphthalamic acid (NPA) and 9-hydroxyfluorene-9-carboxylic acid (HFCA) and methyl jasmonate (JA-Me) were thoroughly investigated. Ethephon was not effective to enhance petiole bending, suggesting that ethylene derived from exogenously applied IAA does not play an important role in petiole bending in detachd leaves of B. calycinum. This suggestion was strongly supported by the fact that ethephon exogenously applied to petioles in intact plant of B. calycinum had no effect on inducing epinasty and/or hyponasty either (Ueda et al., 2018). Potent inhibitors of polar auxin transport, TIBA and HFCA, and JA-Me were extremely effective to inhibit petiole bending but NPA was not. Almost no petiole bending was observed in excised petiole segments without the leaf blade. Applicaton of IAA to the cut surface of petioles in the leaf blade side strongly promoted petiole bending. Polar auxin transport in excised petioles of B. calycinum was intensively investigated using radiolabeled IAA ([1-14C] IAA). Clear polar auxin transport was observed in excised petiole segments, indicating that auxin allows movement in one direction: from the leaf blade side to the stem side in petioles. When detached leaves were placed only leaf blade face down, transported 14C-IAA was reduced in the lower side of the excised petioles. These results strongly suggest that transport and/or lateral movement of endogenous auxin biosynthesized or produced in the leaf blade are necessary to induce petiole bending in detached leaves of B. calycinum. Mechanisms of petiole bending in detached leaves of B. calycinum are also discussed in relation to polar auxin transport and lateral movement of auxin.
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Abstract

During the research interaction of indole-3-acetic acid (IAA) and methyl jasmonate (JA-Me) in epinasty and/or hyponasty, as well as petiole growth of Bryophyllum calycinum were investigated. Exogenously applied IAA as a lanolin paste was extremely effective to induce epinasty and/or hyponasty accompanied with petiole elongation in intact B. calycinum. Application of IAA around or to the upper side of the petiole was much more effective than that to the lower side, suggesting that petiole epidermal cells on the adaxial side of B. calycinum are more sensitive and/or susceptive to IAA than those on the abaxial one. This is supported by the fact that not only the second curvature but also the first one in B. calycinum was enhanced by application of IAA to the upper side of the petiole. The degree of epinasty and/or hyponasty induced by IAA is strongly related to the increase of petiole growth. On the other hand, JA-Me significantly inhibited IAA-inducing epinasty and/or hyponasty, and petiole growth in intact B. calycinum. When detached leaves with petioles were placed leaf blade face down, clear petiole bending was observed. However, no petiole bending was found when detached leaves were placed leaf blade face up. Exogenously applied IAA to petioles was significantly effective to induce and/or stimulate petiole bending in placing detached leaves of B. calycinum face down but ethephon was not, suggesting that transport and/or movement of endogenous auxin produced in the leaf blade are necessary to induce petiole bending in detached leaves of B. calycinum and that ethylene derived from exogenously applied IAA does not play an important role in epinasty and/or hyponasty, and petiole bending in B. calycinum. The mechanisms of IAA-enhancing and JA-Me-inhibiting epinasty and/or hyponasty, and petiole growth are intensively discussed.
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