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Number of results: 19
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Abstract

The paper presents test results for the assessment of the tracer content in a three-component (green peas, sorghum, maize) feed mixture that is based on the fluorescent method. The homogeneity of mixtures was determined on the basis of the maize content (as the key component), which was treated with fluorescent substance: tinopal, rhodamine B, uranine and eosin. The key components were wet-treated with fluorescent substances with different concentrations. Feed components were mixed in a vertical funnel-flow mixer. 10 samples were collected from each mixed batch. Samples were placed in a chamber equipped with UV light and, then, an image recorded as BMP file was generated. The image was analysed by means of the software programme Patan. On the basis of the analyses conducted, data on the maize content marked with a fluorescent marker were obtained. Additionally, the content of the key component was determined in a conventional manner – using an analytical scale. Results indicate the possibility of using this method for homogeneity assessment of the three-component grain mixture. From these tests, fluorescent substances that can be applied in the case of maize as a key component, together with their minimum concentrations, were identified: tinopal 0.3%, rhodamine B 0.001%.

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Authors and Affiliations

Dominika B. Matuszek
Krystian Wojtkiewicz
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Abstract

Fluorescent Pseudomonas (FP) is a major group of plant growth promoting rhizobacteria and a well-known synthesizer of siderophores, which imparts a selective advantage on rhizosphere competence and their biocontrol traits. The present study was aimed at examining the factors affecting the production of siderophores and their potential biocontrol traits. Sixteen FP isolates were shortlisted based on their siderophore-producing ability in chrome azural S medium. The isolates were checked for variations in siderophore production under varying incubation times, temperatures, pH, iron (Fe3+) concentrations and mutagens. In addition, the iron binding affinity of siderophores, mycelial inhibition assay and plant growth promotion traits were assessed. Results showed that the siderophore production was highly influenced by the time of incubation, changes in pH, temperature and iron concentration. Chemical characterization showed that the produced siderophores were hydroxamates. Maximum siderophore production was observed at pH 7 whereas UV and EtBr exposure invariably suppressed siderophore production drastically in all isolates. All FPs from maize rhizosphere showed excellent siderophore production which could be due to the competence in strategy-II of the plant rhizosphere and significant growth inhibition on Fusarium oxysporum. Our results suggest the inclination of siderophores to iron, in terms of various criteria affecting production and the possible role of environmental mutations that affect the natural iron harvesting mechanism.
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Authors and Affiliations

Deori Monali
Jayamohan Nellickal Subramanyan
Kumudini Belur Satyan
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Abstract

Taro leaf blight caused by Phytophthora colocasiae affects plant health and is a major threat to taro culture in Cameroon. Chemical fertilizers used often harm the ecosystem. Plant growth-promoting rhizobacteria (PGPR) are better alternatives that increase plant growth promotion and suppress phytopathogens. In the present study, a total of 67 fluorescent Pseudomonas spp. was characterized by 17.91, 5.97, and 4.47% populations of P. fluorescens, P. chlororaphis, and P. putida, respectively, among the most represented. More than 36% of bacteria showed antagonistic potential through the production of both diffusible and volatile compounds. Some of them (03) exhibited antagonistic activity in dual culture against P. colocasiae with a diameter greater than 13 mm. These rhizobacteria produced a significant amount of siderophore, IAA, SA, HCN, protease, lipases, and cellulases. For the pot experiment, treatment by Pseudomonas significantly increased the enzymatic activity involved in the resistance of taro, such as peroxidase (PO), polyphenol oxidase (PPO), and phenylalanine ammonia-lyase (PAL). The two antagonists also increased plant growth parameters of taro such as chlorophyll, plant height, shoot length, total leaf surface, fresh root biomass, and fresh leaf biomass. These findings showed that fluorescent Pseudomonas have an intriguing and undeniable potential in the fight against P. colocasiae, which could lead to the development of a biopesticide in the future.
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Authors and Affiliations

Samuel Arsène Ntyam Mendo
1
ORCID: ORCID
Dorice Nguelo Dzumafo
2
Laure Brigitte Kouitcheu Mabeku
3
Severin Tchameni Nguemezi
2
ORCID: ORCID
Lambert Sameza Modeste
2
Rosalie Anne Ngono Ngane
2

  1. Department of Biological Sciences, Higher Teacher Training College, University of Yaounde 1, Yaounde, Cameroon
  2. Department of Biochemistry, Faculty of Sciences, University of Douala, Douala, Cameroon
  3. Department of Microbiology, Faculty of Science, University of Yaoundé 1, Yaounde, Cameroon
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Abstract

In the present investigation optical, electro-optical and dielectric properties have been measured for nematic liquid crystal (NLC) material 1550C which consists of 4’-(trans, trans-4-alkylbicyclohexyl) carbonates and 4’-(4-(trans,trans-4-alkyl)-4-cyanobicyclohexane, dispersed with fluorescent dye (Benzo 2,1,3 Thiadiazole) in two different concentrations. Photoluminescence has been enhanced for a dye dispersed system which is the key finding of this investigation. UV absorbance study has also been performed and found to be increased for composite system. Enhanced birefringence after dispersion of dye into pure NLC is also a prominent result of this investigation. Relative permittivity, threshold voltage and dielectric anisotropy have also been measured and found to be increased. The outcome of the present work may be very useful in the construction of liquid crystal displays (LCDs).

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Authors and Affiliations

G. Pathak
K. Agrahari
A. Roy
A. Srivastava
O. Strzezysz
K. Garbat
R. Manohar
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Abstract

The increasing salinity of water in reservoirs is caused by climate change. On the other hand, an increase in salinity promotes the group species, halophytes that tolerate or need NaCl for growth. The aim of this study was to identify the response of facultative halophytes’ photosynthetic apparatus efficiency ( PE) to water salinity. The study covered the spiny water nymph ( Najas marina L.) population in four mining subsidence reservoirs. Najas marina is a facultative halophyte which means that it can occur in both fresh and salt water. This plant has the characteristics of the species invasive, such as rapid biomass growth, and wide ecological tolerance. Water salinity, described by conductivity, in the reservoirs ranged from 646 to 3061 μS∙cm –1. PE was expressed in terms of chlorophyll a fluorescence parameters, which were collected in situ using a Pocket PEA device. Water parameters using a YSI ProDSS probe were identified. Data analysis was performed using OJIP test and s the non-parametric Spearman’s rank test (p ≤ 0.05). The relationship between chlorophyll a fluorescence parameters and water parameters showed that conductivity, salinity, water clarity, and nitrate content statistically significantly affected PE (p <0.05). Generally, the higher salinity e.g. more than 3000 μS∙m –1, supports PE of facultative halophyte at the stage of optimum development in the vegetation season.
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Authors and Affiliations

Edyta Sierka
1
ORCID: ORCID
Michał Bujok
1
ORCID: ORCID
Barbara Stalmachova
2
ORCID: ORCID
Tomasz Horaczek
3
ORCID: ORCID

  1. University of Silesia in Katowice, Institute of Biology, Biotechnology and Environmental Protection, Jagiellońska St. 28, 40-032 Katowice, Poland
  2. VSB Technical University of Ostrava, Institute of Environmental Engineering, VŠB, Ostrava, Czech Republic
  3. Institute of Technology and Life Sciences - National Research Institute, Falenty, Poland
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Abstract

The depletion of natural resources such as freshwater and cropland makes it necessary to find a new solution for sustainable food production. Aquaponic systems seem to be a great alternative to traditional agriculture, however, there are still many unknowns that need to be explored. It is already known how fish stocking affects water quality in aquaponic systems, but not how it affects the plants’ growth, and especially on chlorophyll fluorescence. In this study, we examined how the density of 0, 2, 4, 8, and 16 stocking fish in five aquaria affects lettuce growth. The first tank was only a hydroponic system with plants but without fish (control). In the remaining four aquaria – 2, 4, 8 and 12 specimens of common carp fry with an average weight of 20 grams (average 8.5–33.2 g) were placed in the aquaponic growing system. Physicochemical analysis of water was conducted to determine the levels of pH, electrical conductivity ( EC), N-NO 3, N-NO 2, N-NH 4, P-PO 4, O 2 and physiological parameters of plants (nitrogen balance index – NBI, chlorophyll content index – CCI, quantum yield – QY, flavonoid content – Flv) were analysed. The results showed that fish stocking density has different effects on plant physiological parameters, but in most cases, was insignificant. It seems that the greater number of fishes and higher density indirectly causes growth inhibition (lower photosynthetic efficiency) due to the increase of N-NO 3 and a decrease of O 2 in the water.
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Authors and Affiliations

Zuzanna Malwina Jaszczuk
1
ORCID: ORCID
Adam Brysiewicz
2
ORCID: ORCID
Agnieszka Kozioł
2
Alicja Auriga
3
ORCID: ORCID
Marian Brestic
4
ORCID: ORCID
Hazem M. Kalaji
2 5
ORCID: ORCID

  1. Warsaw University of Life Sciences SGGW, Faculty of Agriculture and Ecology, Warsaw, Poland
  2. Institute of Technology and Life Sciences – National Research Institute, Falenty, 3 Hrabska Ave, 05-090, Raszyn, Poland
  3. West Pomeranian University of Technology in Szczecin, Faculty of Biotechnology and Animal Husbandry, Department of Animal Anatomy and Zoology, Szczecin, Poland
  4. Slovak University in Agriculture in Nitra, Institute of Plant and Environmental Science, Faculty of Agrobiology and Food Resources, Nitra, Slovakia
  5. Warsaw University of Life Sciences SGGW, Institute of Biology, Department of Plant Physiology, Warsaw, Poland
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Abstract

This paper presents a method of optical fluorescence analysis for the evaluation of homogeneity of multicomponent grain mixtures. This method is based on the evaluation of the content of fluorescent marker. Maize with two degrees of fineness d1 = 1:25 mm and d2 = 2:00 mm was used as a tracer. Maize was covered with Rhodamine B, which emits red light under the influence of ultraviolet radiation. The tracer was introduced into the mixture before the mixing process began. Nine multicomponent grain mixtures were used. The proportion of fluorescent maize was evaluated on the basis of computer image analysis. Additionally, the fraction of the tracer was evaluated using a control method (validation of the accuracy of the proposed method). The results indicate that the degree of the tracer’s fineness influences the results obtained. The use of fluorescent maize with particle size d2 = 2:00 mm allowed to obtain results which differed less from the control method. The average size of the difference in results ranged from 0.20–0.38 for the 2.00 mm tracer and 0.38–1.34 for the 1.25 mm tracer.
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Authors and Affiliations

Dominika B. Matuszek
1
Jolanta B. Królczyk
2

  1. Opole University of Technology, Faculty of Production Engineering and Logistics, Department of Biosystems Engineering and Chemical Processes, Mikolajczyka 5, 45-271 Opole, Poland
  2. Opole University of Technology, Faculty of Mechanical Engineering, Department of Manufacturing and Materials Engineering, Mikolajczyka 5, 45-271 Opole, Poland
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Abstract

Opal can be found in several locations, including America, Tanzania, Brazil, Mexico, East Africa, Indonesia and Australia, which is now the world’s top producer of black opal. One of the most economically valuable gems in the world is the mineraloid opal. In the Rongkong area, opal is found in the host rock of volcanic igneous rock, namely andesite. This study aims to determine the opal mineraloid host-rock’s microstructural characteristics and the elemental and compound content of the opal mineraloid host-rock’s geochemistry in the Rongkong area, Indonesia. The research took three samples in the field as large as hand specimens. The three samples were one host-rock sample and two opal mineraloid samples; the samples were then prepared and analyzed in the laboratory. Laboratory analysis was performed using SEM-EDS, XRF and petrographic analyses. The results of the SEM-EDS test analysis showed that most opal mineraloid carrier rock constituents are aluminum and oxide. This can be seen from the substantial Al and O content. In samples 1 and 2, Al, O, Ca and P with the highest composition of chemical compounds are Al2O3, CaO, and P2O5. The Rongkong opal mineraloid from Limbong Village, Rongkong District, North Luwu Regency, South Sulawesi, based on the results of XRF analysis, contains the chemical compounds SiO2, Al2O3, K2O, Fe2O3, CaO, TiO2, RuO2, SrO, MnO, V2O5, Rb2O, Ag2O and CuO. The content compound that is more dominant in opal mineraloids is SiO2 due to silicate enrichment in the forming of opal mineraloids.
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Authors and Affiliations

Alam B. Thamsi
1
ORCID: ORCID
Agus A. Budiman
1
Emi P. Umar
1
Harwan Harwan
1

  1. Universitas Muslim Indonesia, Indonesia
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Abstract

This study presents the determination of the content of selected metals (Ba, Ca, Fe, Nb, Rb, Sr, Y, Zn, and Zr) in postglacial deposits from two glacial valleys (Ebbadalen and Elsadalen) in the Petunia Bay (southern Spitsbergen). The aim of the research was to experimentally check the usefulness of the handheld energy dispersive X-ray fluorescence technique in the study of samples from the polar zone, before performing the future field tests. Deposit analyses were performed (in parallel) with two handheld X-ray fluorescence spectrometers from different manufacturers, to investigate the accuracy and reliability of the instruments. The statistical analysis of the results indicated that the measurements carried out with two spectrometers were statistically significantly different, which was probably due to the different calibration characteristics used by the manufacturers. However, the analysis of the spatial distribution of element concentrations using Geographic Information System tools showed that the distribution maps of elements concentrations were similar regardless of the spectrometer used in the analyses.
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Authors and Affiliations

Lidia Kozak
1
Juliana Silva Souza
1
Adam Nawrot
2
Jędrzej Proch
1
Marcin Kaźmierski
3
Agnieszka Zawieja
4
Przemysław Niedzielski
1

  1. Adam Mickiewicz University in Poznań, Faculty of Chemistry, Department of Analytical Chemistry, Uniwersytetu Poznańskiego 8, 61-614 Poznań, Poland
  2. Institute of Geophysics Polish Academy of Sciences, Księcia Janusza 64, 01-452 Warszawa, Poland
  3. Adam Mickiewicz University in Poznań, Faculty of Geographical and Geological Sciences, Bogumiła Krygowskiego 10, 61-680 Poznań, Poland
  4. MEWO S.A., Starogardzka 16, 83-010 Straszyn, Poland
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Abstract

The subject of this work was the investigation of zeolite as a sorbent of toxic gases. In Nizny Hrabovec in the Slovak republic, two layers of zeolite with the active component clinoptilolite can be found. The study presented here investigated the ability of this natural zeolite to reduce polycyclic aromatic hydrocarbons (PAH) and NO emissions from engine exhaust. Exhaust gases from combustion engines include toxic components such as carbon monoxide, nitrogen oxides and hydrocarbons. Polycyclic aromatic hydrocarbons (PAH) are a component of hydrocarbons causing harmful influence on life forms. The experiments focused on the potential reduction of these toxic gases based on the sorption and catalytic properties of natural zeolite. Also observed was the influence of chemical adjustment including incorporation of certain metal elements. Chemical analysis by mutually independent technologies served to observe the sorption of PAH with carcinogenic properties on the natural zeolite tested. The experiments showed that chemical modification improved the sorption and catalytic properties of natural zeolite. The PAH were analysed in an extract of the contaminated, thermally-activated natural zeolite and modified zeolite after washing with ammonium chloride, cobalt chloride and copper sulphate. The study also presents results of NO measurements obtained by testing the filter-sorptive automobile system.

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Authors and Affiliations

Jozef Mačala
Iveta Pandová
Taťána Gondová
Katarína Dubayová
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Abstract

Using Langmuir and Langmuir-Blodgett techniques molecular films of chlorinated perylene derivatives, namely tetra-n-butyl-1,6,7,12-tetrachloroperylene-3,4,9,10-tetracarboxylate (PCn for n = 1, 5, 9) have been studied. The Langmuir films of pure compounds and mixed with liquid crystalline 4-octyl-4′-cyanobiphenyl (8CB) were characterized by surface pressure-mean molecular area isotherms. An additive rule reveals miscibility of all the dyes with 8CB but shows different types of intermolecular interaction forces. The pure and mixed Langmuir films were transferred onto quartz plates and characterized spectroscopically. Absorption and fluorescence spectra were recorded for the samples in form of diluted chloroform solution, the dye with 8CB mixtures in monomolecular Langmuir-Blodgett films and in liquid crystal cells. Different tendency to aggregation of the dye with short and long alkyl chains was observed. It is shown that the dye molecule stacking and aggregation of the chlorinated perylene dyes depend on the dye concentration and are related to the torsion of the perylene core.

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Authors and Affiliations

A. Modlińska
E. Chrzumnicka
T. Martyński
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Abstract

In this work a review of investigations concerning interaction of intense extreme ultraviolet (EUV) and soft X-ray (SXR) pulses with matter is presented. The investigations were performed using laser-produced plasma (LPP) EUV/SXR sources based on a double stream gas puff target. The sources are equipped with dedicated collectors allowing for efficient focusing of the EUV/SXR radiation pulses. Intense radiation in a wide spectral range, as well as a quasi-monochromatic radiation can be produced. In the paper different kinds of LPP EUV/SXR sources developed in the Institute of Optoelectronics, Military University of Technology are described.

Radiation intensities delivered by the sources are sufficient for different kinds of interaction experiments including EUV/SXR induced ablation, surface treatment, EUV fluorescence or photoionized plasma creation. A brief review of the main results concerning this kind of experiments performed by author of the paper are presented. However, since the LPP sources cannot compete with large scale X-ray sources like synchrotrons, free electron lasers or high energy density plasma sources, it was indicated that some investigations not requiring extreme irradiation parameters can be performed using the small scale installations. Some results, especially concerning low temperature photoionized plasmas are very unique and could be hardly obtained using the large facilities.

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Authors and Affiliations

A. Bartnik
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Abstract

This article is focused on considerations based on experimental studies concerning changes of selected parameters of identical compact fluorescent lamps (CFLs) intended for use in buildings during their operation. The studies constituted a long-term experiment whose goal was an evaluation of selected operating parameters of the CFLs in terms of meeting the requirements set out in the specified regulations as well as the issue of marking the lamps with the energy efficiency class. The measurements were performed with the authors’ experimental setup consisting of original equipment designed and made especially for the purpose of the measurements. The studies covered registration of the luminous flux as well as selected electrical parameters such as active power, current and the power factor during the so-called “start-up time” and operation time equal to 100 h, 500 h, 1000 h, 2000 h, etc. with a 1000 h step. The studies were finished with the moment of natural burnout of the CFLs tested. The results showed that the biggest drawback of CFLs is lack of preservation of the required time to reach 60% of the stabilized luminous flux just after short time of lamp operation. Similarly when assessing the conformity of the parameters declared by the manufacturer that have been verified, it can be stated that they are true only at the initial stage of lamp operation.

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Authors and Affiliations

Jarosław Zygarlicki
Małgorzata Zygarlicka
Janusz Mroczka
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Abstract

This article is focused on considerations based on experimental studies concerning changes of selected parameters of identical compact fluorescent lamps (CFLs) intended for use in buildings during their operation. The studies constituted a long-term experiment whose goal was an evaluation of selected operating parameters of the CFLs in terms of meeting the requirements set out in the specified regulations as well as the issue of marking the lamps with the energy efficiency class. The measurements were performed with the authors’ experimental setup consisting of original equipment designed and made especially for the purpose of the measurements. The studies covered registration of the luminous flux as well as selected electrical parameters such as active power, current and the power factor during the so-called “start-up time” and operation time equal to 100 h, 500 h, 1000 h, 2000 h, etc. with a 1000 h step. The studies were finished with the moment of natural burnout of the CFLs tested. The results showed that the biggest drawback of CFLs is lack of preservation of the required time to reach 60% of the stabilized luminous flux just after short time of lamp operation. Similarly when assessing the conformity of the parameters declared by the manufacturer that have been verified, it can be stated that they are true only at the initial stage of lamp operation.

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Authors and Affiliations

Przemysław Tabaka
ORCID: ORCID
Paweł Rózga
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Abstract

Salt stress is one of the main factors disturbing the physiology of organisms, including epigeic lichens inhabiting roadsides, due to de-icing salts used in winter seasons. The aim of the research was to study the effect of acute salt stress in various doses on the chlorophyll fluorescence parameters of chlorolichens, i.e., Cladonia furcata, C. mitis, Diposchistes muscorum, and cyanolichens, i.e., Peltigera didactyla, and P. rufescens, which naturally grow inland in the vicinity of roads. We also aimed to study changes in the photosynthetic efficiency of lichens over time and their responses to rainfall simulations in the days following exposure to salt stress to test whether liquid water supply improves photosynthetic efficiency. Salt stress led to a reduction of it in cyanolichens in most experimental groups, while in chlorolichens only treatment with 2.9-3.9M NaCl solutions significantly decreased FV/FM. Exposure to acute salt stress significantly affected fluorescence transient curves in all studied species. With respect to chlorolichens, a marked decrease of FM was observed and the flattened shape of the transient curves after treatment with the highest salt doses was the most apparent. Significantly greater disturbances were observed in cyanolichens in which the induction curve lost its sigmoid characteristics after treatment with solutions with a concentration greater than 0.35M. Furthermore, in all lichen species, increased values of ABS/RC and DI 0/RC and decreases in PI ABS, ET 0/RC and TR0/RC as well as quantum yields and efficiencies were observed. Simulated rainfall resulted in a significant increase in the photosynthetic efficiency of chlorolichens to a level corresponding to healthy lichens almost throughout the duration of the whole experiment. On the contrary, in the case of cyanolichens, significant increases in FV/FM after water treatment were found only after exposure to low salt doses and, at the latest, 24 h after the stress. Although many cyanobacteria developed adaptations to survive in highly saline environments, cyanobionts present in inland lichen species seem to be highly susceptible to salt stress. We concluded that the time when rainfall occurs after exposure to salt stress is a crucial factor affecting the potential regeneration of PSII efficiency. Regeneration after rainfall is an important aspect for epigeic lichens occurring near roadsides, where, during the winter season, they are exposed to de-icing salt for a long time, and rainfall may partially compensate for their disturbances and increase their photosynthetic efficiency, enhancing the possibility of survival.
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Authors and Affiliations

Karolina Chowaniec
1
ORCID: ORCID
Jakub Styburski
1
Kaja Rola
1
ORCID: ORCID

  1. Institute of Botany, Faculty of Biology, Jagiellonian University, Gronostajowa 3, 30-387 Kraków, Poland
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Abstract

Drought significantly impacts the growth and yield of forage grasses, particularly its effect on Dactylis glomerata photosynthetic apparatus during the initial phase of development remains largely unknown. This study investigated the effects of drought on physiological parameters of various D. glomerata varieties. The seedlings obtained after seed germination under optimal and simulated drought conditions by PEG 6000 (three variants) were planted in small pots filled with garden substrate. Over a span of 42 days, the plants were initially kept well-watered (70% capillary water capacity, CWC), after which half of the seedlings from each variant were subjected to drought. This drought stress was applied during the tillering phase for 12 days. Subsequently, the plants were rehydrated (at 70% CWC) and allowed to recover for 14 days. Throughout both drought and recovery periods, measurements were taken. Leaf chlorophyll fluorescence parameters were assessed, and the JIP-test analysis was utilised to provide detailed insights into the functionality of D. glomerata photosynthetic apparatus under drought stress and post-recovery conditions. Several parameters were identified as indicative of the plants’ sensitivity to drought, such as performance indices PI ABS and PI tot, along with quantum yield parameters Ψ E0, φ E0, and φ P0. The results highlighted that var. Minora and Tukan exhibited greater tolerance to water deficit when compared to the other varieties studied. They showed a large increases in PIABS and PItot values after drought stress as well as after the re-watering (recovery period) compared to control plants. This suggests their potential for better adaptation to drought conditions.
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Authors and Affiliations

Barbara Borawska-Jarmułowicz
1
ORCID: ORCID
Grażyna Mastalerczuk
1
ORCID: ORCID
Piotr Dąbrowski
2
ORCID: ORCID
Żaneta Tuchowska
1
ORCID: ORCID
Hazem Kalaji
3
ORCID: ORCID

  1. Warsaw University of Life Sciences – SGGW, Institute of Agriculture, Nowoursynowska St, 159, 02-776 Warsaw, Poland
  2. Warsaw University of Life Sciences – SGGW, Institute of Environmental Engineering, Nowoursynowska St, 159, 02-776 Warsaw, Poland
  3. Institute of Technology and Life Sciences – National Research Institute, Falenty, Hrabska Ave, 3, 05-090 Raszyn, Poland
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Abstract

Abiotic stressors contribute to growth restriction and developmental disorders in plants. Early detection of the first signs of changes in plant functioning is very important. The objective of this study was to identify chlorophyll fluorescence parameters that change under phosphorus deficiency stress in cucumber. In this work, a trail to study the early changes caused by phosphorus deficiency in cucumber plants by analysing their photosynthetic performance is presented. Chlorophyll- a fluorescence (ChF) parameters were measured every 7 days for a period of 28 days. Measurements were made separately on young and old leaves and on cucumber fruit. Parameters that decreased during the stress were: p2G, PI abs, PI total, REo/CS o, and TRo/CSo. P deficiency decreased total electron carriers per RC ( ECo/RC), yields ( TRo/ABS ( Fv/Fm), ETo/TRo, REo/ETo, ETo/ABS and REo/ABS), fluxes ( REo/RC and REo/CSo) and fractional reduction of PSI end electron acceptors, and damaged all photochemical and non-photochemical redox reactions. Principal component analysis revealed a group of ChF parameters that may indicate early phosphorus deficiency in cucumber plants. Our results are used in the discovery of sensitive bioindicators of phosphorus deficiency in cucumber plants. Most JIP test parameters are linked to mathematical equations, so we recommend using of advanced statistical tools, such as principal component analysis, which should be considered very useful for stress identification. It has also been shown to be more effective in multivariate methods compared to univariate statistical methods was demonstrated.
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Authors and Affiliations

Leszek Sieczko
1
ORCID: ORCID
Piotr Dąbrowski
2
ORCID: ORCID
Katarzyna Kowalczyk
3
ORCID: ORCID
Janina Gajc-Wolska
3
ORCID: ORCID
Wojciech Borucki
4
ORCID: ORCID
Monika Janaszek-Mańkowska
5
ORCID: ORCID
Waldemar Kowalczyk
6
ORCID: ORCID
Domenica Farci
7
Hazem M. Kalaji
7
ORCID: ORCID

  1. Warsaw University of Life Sciences – SGGW, Department of Biometry, Institute of Agriculture, 166 Nowoursynowska St., 02-787 Warsaw, Poland
  2. Warsaw University of Life Sciences – SGGW, Department of Environmental Management, Institute of Environmental Engineering, Poland
  3. Warsaw University of Life Sciences – SGGW, Department of Vegetable and Medicinal Plants, Institute of Horticultural Sciences, Poland
  4. Warsaw University of Life Sciences – SGGW, Department of Botany, Institute of Biology, Poland
  5. Warsaw University of Life – SGGW, Department of Fundamentals of Engineering and Power Engineering, Institute of Mechanical Engineering, Poland
  6. The National Institute of Horticultural Research, Skierniewice, Poland
  7. Warsaw University of Life Sciences – SGGW, Department of Plant Physiology, Institute of Biology, Poland
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Abstract

To study the influence of structural features of phthalocyanine (Pc) derivatives on their physico-chemical properties in bulk and thin films, 23 new phthalocyanines with different quantity and ratio of donor (alkyloxy-groups, in fragment “A”) and acceptor (Cl-, in fragment “B”) substituents in one molecule of the A3B, ABAB and AABB types with varied length of alkyloxy-substituents and their metal complexes were designed and synthesized. A comparative analysis of spectral, mesomorphic and photoelectric properties of these mix-substituted phthalocyanines of a “push–pull” type was performed. It was shown that non-peripheral substitution by alkyloxy-fragments in hetero-substituted Pcs (similar to homo-substituted Pc) leads to red-shifting of the Q-band into near-IR region. The intensity of photoluminescence, position of peaks and their splitting are strongly connected with chemical structure of Pcs and the type of solvent. In contrast to non-mesogenic octyloxy-Pc (A4) having alkyloxy-substituents in non-peripheral positions, 22 of 23 synthesized compounds possess columnar mesomorphism. The change of donor–acceptor ratio can influence the type of mesophase. A new approach to the creation of materials for optoelectronics is proposed and implemented, which includes design of compounds possessing vitrification from mesophase with maintenance of a columnar order, absorption in the near IR-region of the spectrum and good performance electrophysical characteristics simultaneously.

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Authors and Affiliations

N.V. Usol’tseva
A.I. Smirnova
A.V. Kazak
N.I. Giricheva
N.E. Galanin
G.P. Shaposhnikov
V.V. Bodnarchuk
S.V. Yablonskii
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Abstract

The vitality of lichens and their growth depend on the physiological status of both the fungal and algal partner. Many epiphytic lichens demonstrate high specificity to a habitat type and hygrophilous species are, as a rule, confined to close-to-natural forest complexes. Tolerance to desiccation stress and the rate of photosynthesis activation upon thallus hydration vary between species. Analyzes of chlorophyll fluorescence and photosynthesis efficiency have been widely applied to determine the viability of lichens. The aim of this study was to determine the activation photosynthesis rate upon hydration in epiphytic lichens exposed to short-term desiccation stress and to find potential links between their activation pattern and ecological properties. The results proved that even highly sensitive hygrophilous lichens, i.e., Cetrelia cetrarioides, Lobaria pulmonaria, Menegazzia terebrata, do not exhibit any delay in the restart of the photosynthesis process, compared to mesophytic or xerophytic ones. All examined lichens achieved nearly 100% of their maximum photosynthetic efficiency just one hour after they had been supplied with a relatively small quantity of water. Moreover, the increase in photosynthesis efficiency, measured at 20-minute intervals upon hydration, started from a relatively high level. In addition, the differences in the content of photosynthetic pigments and water holding capacity between species did not affect the general pattern of activation, which is comparable across various lichens. It can be concluded that healthy hygrophilous lichens do not require long hydration time to regain a high level of photosynthesis efficiency after a short rainless period. This fact supports the idea of applying chlorophyll fluorescence analysis in the field to assess vitality of lichens and the condition of their natural habitat.
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Authors and Affiliations

Piotr Osyczka
1
ORCID: ORCID

  1. Institute of Botany, Faculty of Biology, Jagiellonian University, Gronostajowa 3, 30-387 Kraków, Poland

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