22 research outputs found
Zmiany w komórkach mezofilu liści roślin Lycopersicon esculentum Mill. spowodowane zasoleniem
Five-week-old tomato plants (Lycopersicon esculentum) cv. Perkoz grown in pots
containing garden soil in a growth chamber were submitted to 50 or 150 mM NaCl for
1 h, 2 and 5 days. Tomato leaf anatomy generally did not change after short time
salinity, except 5-day-treatment with 150 mM NaCl, where changed cell shape
(shrunk and deformed) simultaneously with increased volume of intercellular spaces
(IS) were observed. Although leaf hydration (H) depleted only 1 h after 150 mM NaCl
treatment both salt concentrations generated two coexisting populations of saltaffected
mesophyll cells: (i) slightly-affected (Sl-A) which showed incipient
plasmolysis or slightly changed shapes, and (ii) severely-affected (Sv-A) which
showed severe plasmolysis; serious deformation of cell shape or disorganization
including cell degeneration. In Sl-A cells salinity changed location and shape of
chloroplasts which were: more rounded, with oversized starch grains (SG) (2d) or
more flat (5d). Salt-mediated changes were becoming more distinguished and
pronounced with length of 150 mM NaCl treatment. The amount of salt-affected cells
was changing during the experiment and depended on the salt concentration. In 50
mM-treated plants salt-affected cells appeared 1 h after treatment (~40%) and raised
up to 78% on 2nd day, however the population of Sl-A cells dominated. In 150 mM
NaCl-treated plants the percentage of affected cells raised during the experiment
from 75% to 99%. Firstly Sl-A cells dominated, but on the 5th day the majority was
Sv-A. Salt-affected cells were distributed quite evenly in palisade or spongy
mesophyll, except 2 d after treatment with 50 mM NaCl, when their number was
higher in the palisade mesophyll. Sv-A cells in the spongy mesophyll were located
mostly near the bundle while in the palisade mesophyll more irregularly. Different
susceptibility of cells to salt stress might be the consequence of an unequal
distribution of osmotic stress and subsequent ionic stress or physiological state of
cells
XIV Ogólnopolska Konferencja Polskich Bibliotek Prawniczych "Biblioteka prawnicza jako warsztat pracy prawnika - badacza - naukowca" : (Warszawa, 22-23 września 2016 r.)
"XIV Ogólnopolska Konferencja Polskich Bibliotek Prawniczych pod
hasłem „Biblioteka prawnicza jako warsztat pracy prawnika – badacza –
naukowca” odbyła się w dniach 22–23 września 2016 r. w Warszawie.
Jej organizatorami były biblioteki: Instytutu Nauk Prawnych Polskiej
Akademii Nauk, Wydziału Prawa i Administracji Uniwersytetu Warszawskiego,
Wydziału Prawa i Administracji Uniwersytetu Kardynała
Stefana Wyszyńskiego oraz Kancelaria Hogan Lovells. Pierwsza Konferencja
została zainicjowana w 2003 r. przez Bibliotekę Wydziału
Prawa, Administracji i Ekonomii Uniwersytetu Wrocławskiego." […] (fragm.
Spotkanie kierowników bibliotek prawniczych
Już po raz siódmy, pod koniec czerwca (26-27 VI 2009 r.), odbyło
się Spotkanie Kierowników Bibliotek Prawniczych, tradycyjnie organizowane
przez różne biblioteki, dotychczas we Wrocławiu, Słubicach/
Frankfurcie/Berlinie, Szczecinie, Katowicach/Krakowie, Toruniu
i w Warszawie. Tegoroczne spotkanie zorganizowała Biblioteka
Collegium Polonicum w Słubicach. Położone przy granicy polsko-niemieckiej
Słubice oraz Frankfurt nad Odrą pełnią funkcję pomostu
między Wschodem a Zachodem, Collegium Pollonicum zaś ukierunkowało
swoje działania na rzecz naukowej i kulturowej współpracy
między Polską a Niemcami, jako formy współpracy transgranicznej
w dziedzinie badań i dydaktyki, realizowanej przez Uniwersytet im.
Adama Mickiewicza w Poznaniu i Uniwersytet Europejski Viadrina we
Frankfurcie. Działająca przy Collegium Biblioteka jest naukowym zapleczem
programów badawczych obu uniwersytetów[…
Biblioteka Wydziału Prawa i Administracji UŚ - wczoraj, dziś i jutro
The article describes the library at the Faculty of Law and Administration at the University of Silesia in
Katowice. After short historical outline, the authors draw attention to the library resources and its development
plans for several years
The effect of EDTA and EDDS on lead uptake and localization in hydroponically grown Pisum sativum L.
Pisum sativum plants were treated for 3 days
with an aqueous solution of 100 lM Pb(NO3)2 or with a
mixture of lead nitrate and ethylenediaminetetraacetic acid
(EDTA) or [S,S]-ethylenediaminedisuccinic acid (EDDS)
at equimolar concentrations. Lead decline from the incubation
media and its accumulation and localization at the
morphological and ultrastructural levels as well as plant
growth parameters (root growth, root and shoot dry weight)
were estimated after 1 and 3 days of treatment. The tested
chelators, especially EDTA, significantly diminished Pb
uptake by plants as compared to the lead nitrate-treated
material. Simultaneously, EDTA significantly enhanced Pb
translocation from roots to shoots. In the presence of both
chelates, plant growth parameters remained considerably
higher than in the case of uncomplexed Pb. Considerable
differences between the tested chelators were visible in Pb
localization both at the morphological and ultrastructural
level. In Pb?EDTA-treated roots, lead was mainly located
in the apical parts, while in Pb?EDDS-exposed material
Pb was evenly distributed along the whole root length.
Transmission electron microscopy and EDS analysis
revealed that in meristematic cells of the roots incubated in
Pb?EDTA, large electron-dense lead deposits were located
in vacuoles and small granules were rarely noticed in cell
walls or cytoplasm, while after Pb?EDDS treatment metal
deposits were restricted to the border between plasmalemma
and cell wall. Such results imply different ways of
transport of those complexed Pb forms.The X-ray microanalysis was performed in the
Laboratory of Electron Microscopy, Nencki Institute of Experimental
Biology, Warsaw, Poland at the equipment installed within the project
sponsored by the EU Structural Funds: Centre of Advanced Technology
BIM—Equipment purchase for the Laboratory of Biological
and Medical Imaging.
Conflict of interest T
The effect of pre-incubation of Allium cepa L. roots in the ATH-rich extract on Pb uptake and localization
The positive influence of anthocyanin (ATH) on toxic metal-treated plant material is well documented; however, it is still not explained if it is caused by changes in element absorption and distribution. Therefore, detailed analysis of the effect of the ATH-rich extract from red cabbage leaves on Pb uptake and localization at morphological, anatomical and ultrastructural level was the goal of this study. Two-day-old adventitious roots of Allium cepa L. (cv. Polanowska) were treated for 2 h with the aqueous solution of Pb(NO3)2 at the concentration of 100 μM with or without preliminary incubation in the anthocyanin-rich extract from Brassica oleracea L. var. capitata rubra leaves (250 μM, 3 h). The red cabbage extract did not change the total Pb uptake but it enhanced the translocation of accumulated metal from roots to shoots. Within the pretreated roots, more Pb was deposited in their basal part and definitely smaller amount of the metal was bound in the apoplast of the outer layers of cortex cells. The ultrastructural analysis (transmission electron microscopy and X-ray microanalysis) revealed that the ATH-rich extract lowered the number of Pb deposits in intracellular spaces, cell wall and cytoplasm of root meristematic cells as well as in such organelles important to cell metabolism as mitochondria, plastids and nucleus. The Pb deposits were preferably localised in those vacuoles where ATH also occurred. This sequestration of Pb in vacuoles is probably responsible for reduction of metal cytotoxicity and consequently could lead to better plant growth.This work was supported by the grant of the
University of Lodz, no. 505/04038
Metal Homeostasis and Gas Exchange Dynamics in Pisum sativum L. Exposed to Cerium Oxide Nanoparticles
Cerium dioxide nanoparticles are pollutants of emerging concern. They are rarely immobilized in the environment. This study extends our work on Pisum sativum L. as a model plant, cultivated worldwide, and is well suited for investigating additive interactions induced by nanoceria. Hydroponic cultivation, which prompts accurate plant growth control and three levels of CeO2 supplementation, were applied, namely, 100, 200, and 500 mg (Ce)/L. Phytotoxicity was estimated by fresh weights and photosynthesis parameters. Additionally, Ce, Cu, Zn, Mn, Fe, Ca, and Mg contents were analyzed by high-resolution continuum source atomic absorption and inductively coupled plasma optical emission techniques. Analysis of variance has proved that CeO2 nanoparticles affected metals uptake. In the roots, it decreased for Cu, Zn, Mn, Fe, and Mg, while a reversed process was observed for Ca. The latter is absorbed more intensively, but translocation to above-ground parts is hampered. At the same time, nanoparticulate CeO2 reduced Cu, Zn, Mn, Fe, and Ca accumulation in pea shoots. The lowest Ce concentration boosted the photosynthesis rate, while the remaining treatments did not induce significant changes. Plant growth stimulation was observed only for the 100 mg/L. To our knowledge, this is the first study that demonstrates the effect of nanoceria on photosynthesis-related parameters in peas
Complexity of Brassica oleracea–Alternaria brassicicola Susceptible Interaction Reveals Downregulation of Photosynthesis at Ultrastructural, Transcriptional, and Physiological Levels
Black spot disease, caused by Alternaria brassicicola in Brassica species, is one of the most devastating diseases all over the world, especially since there is no known fully resistant Brassica cultivar. In this study, the visualization of black spot disease development on Brassica oleracea var. capitata f. alba (white cabbage) leaves and subsequent ultrastructural, molecular and physiological investigations were conducted. Inter- and intracellular hyphae growth within leaf tissues led to the loss of host cell integrity and various levels of organelle disintegration. Severe symptoms of chloroplast damage included the degeneration of chloroplast envelope and grana, and the loss of electron denseness by stroma at the advanced stage of infection. Transcriptional profiling of infected leaves revealed that photosynthesis was the most negatively regulated biological process. However, in infected leaves, chlorophyll and carotenoid content did not decrease until 48 hpi, and several chlorophyll a fluorescence parameters, such as photosystem II quantum yield (Fv/Fm), non-photochemical quenching (NPQ), or plant vitality parameter (Rdf) decreased significantly at 24 and 48 hpi compared to control leaves. Our results indicate that the initial stages of interaction between B. oleracea and A. brassicicola are not uniform within an inoculation site and show a complexity of host responses and fungal attempts to overcome host cell defense mechanisms. The downregulation of photosynthesis at the early stage of this susceptible interaction suggests that it may be a part of a host defense strategy, or, alternatively, that chloroplasts are targets for the unknown virulence factor(s) of A. brassicicola. However, the observed decrease of photosynthetic efficiency at the later stages of infection is a result of the fungus-induced necrotic lesion expansion
Benzannulation of a ditopic ligand to afford mononuclear and dinuclear Ir(iii) complexes with intense phosphorescence: applications in singlet oxygen generation and bioimaging
Annulation of the additional aromatic pi-system to the ligand is an effective method of influencing the luminescence of metal complexes. In this contribution, we show the effect of benzannulation of a ditopic ligand on the photophysical properties of a dinuclear Ir(iii) complex and also utilize it to prepare its mono-nuclear analogue. The new dinuclear complex di-Ir in which the iridium centres are linked by benzo[1,2-d : 4,5-d']bisthiazole shows drastically improved efficiency of phosphorescence compared to the previously reported complex Ir-2 that has thiazolo[5,4-d]thiazole as the linking unit. The new mono-nuclear complex mono-Ir, utilizing the same ditopic ligand as di-Ir, allows tracking the effects of dinuclearity. In degassed dilute dichloromethane solution, the mononuclear complex mono-Ir displays yellow phosphorescence (lambda(em) = 552 nm) with a quantum yield of phi(PL) = 70% and decay time of tau = 7.85 mu s, which correspond to the radiative rate of k(r) = 0.89 x 10(5) s(-1). The dinuclear complex di-Ir displays slightly red-shifted phosphorescence (lambda(em) = 560 nm) with a quantum yield of phi(PL) = 85% and decay time of tau = 4.50 mu s corresponding to the radiative rate of k(r) = 1.90 x 10(5) s(-1), which is about two times higher compared to that of the mono-nuclear mono-Ir. The phosphorescence intensity of both complexes is highly sensitive to molecular oxygen, as in the air-equilibrated samples the decay times drop to values tau = 0.73 mu s and tau = 0.84 mu s for mono-Ir and di-Ir, respectively. Applied as singlet oxygen sensitizers, mono-Ir and di-Ir show very high efficiencies of 78% and 71%, respectively. Such characteristics mean the two complexes are promising materials for optical oxygen sensing and applications associated with singlet oxygen generation