bluuebunny/crossref_metadata_2025 huggingface dataset:
Propagación asexual de Pinus leiophylla Schiede ex Schltdl. et Cham.
Authors: Cuevas-Cruz Juan Carlos , Jiménez-Casas Marcos , Jasso-Mata Jesús , Pérez-Rodríguez Paulino , López-Uptón Javier , Villegas-Monter Ángel
Published: May 2015

El efecto del sustrato, tipo de estaca y concentración de ácido indolbutírico (AIB) se evaluó en el enraizado de estacas de Pinus leiophylla con el propósito de multiplicar progenies de familias de medios hermanos con crecimiento sobresaliente. Para ello se utilizaron dos tipos de sustratos (agrolita y una mezcla de turba-agrolita-vermiculita 1:1:1), dos tipos de estacas (apicales y basales) y dos concentraciones de AIB (0 y 10,000 ppm). La probabilidad y porcentaje de enraizado, crecimiento de la estaca y características de las raíces formadas deP. leiophylla se evaluaron. Los resultados indican que usando estacas basales es 3.5 veces másprobable que el enraizamiento de P. leiophylla sea exitoso que utilizando estacas apicales.El tratamiento formado por la mezcla de turba-agrolita-vermiculita, estaca basal y 10,000 ppm de AIB produjo 45.3 % de enraizamiento (mayor porcentaje), mientras que con el testigo solo se obtuvo 8.6 % de enraizamiento (agrolita, estaca basal y sin AIB). Las interacciones que incluyeron el tipo de sustrato mostraron diferencias significativas (P ≤ 0.05) en el crecimientode la estaca. El uso de agrolita y la aplicación de AIB favorecieron un mayor número de raíces,particularmente en las estacas tipo basal de P. leiophylla.
Modelo compatible de altura dominante - índice de sitio para táscate (Juniperus deppeana Steud.)
Authors: Rodríguez-Carrillo Antonio , Cruz-Cobos Francisco , Vargas-Larreta Benedicto , Hernández Francisco J.
Published: May 2015

El objetivo de este trabajo fue determinar la calidad de estación de táscate (Juniperusdeppeana Steud.), a través del método de índice de sitio, en la región de San Dimas, Durango. La base de datos proviene de 43 análisis troncales de árboles derribados en actividades de aprovechamiento. Los modelos de Chapman-Richards y de Schumacher, mediante los procedimientos de diferencias algebraicas y diferencias algebraicas generalizadas, se probaron para determinar el índice de sitio; además, se modeló la estructura del error con un modelo autorregresivo de segundo orden para corregir la dependencia de errores longitudinales presentes. Los resultados mostraron que el modelo de Chapman-Richards en diferencias algebraicas generalizadas presentó el mejor ajuste de acuerdo con el coeficiente de determinación ajustado (R2 adj = 0.98) y la raíz del cuadrado medio del error (RCME = 0.46 m). La representación gráfica de las curvas de calidad generadas con este modelo, sobrepuestas a las alturas observadas, corroboraron la bondad de ajuste del modelo seleccionado. La ecuación obtenida con la metodología de diferencias algebraicas generalizadas estima directamente la altura dominante y el índice de sitio a cualquier altura y edad de referencia.
Elevated ozone in boreal fire plumes – the 2013 smoke season
Authors: Trickl T. , Vogelmann H. , Flentje H. , Ries L.
Published: May 2015

Abstract. In July 2013 very strong boreal fire plumes were observed at the northern rim of the Alps by lidar and ceilometer measurements of aerosol, ozone and water vapour for about three weeks. In addition, some of the lower-tropospheric components of these layers were analyzed at the Global Atmosphere Watch laboratory at the Schneefernerhaus high-altitude research station (2650 m a.s.l., located a few hundred metres south-west of the Zugspitze summit). The high amount of particles confirms our hypothesis that fires in the Arctic regions of North America have a much stronger impact on the Central European atmosphere than the multitude of fires in the United States. This has been ascribed to the prevailing anticyclonic advection pattern during favourable periods and subsidence, in contrast to warm-conveyor-belt export, rainout and dilution frequently found for lower latitudes. A high number of the pronounced aerosol structures were positively correlated with elevated ozone. Chemical ozone formation in boreal fire plumes is known to be rather limited. Indeed, these air masses could be attributed to stratospheric air intrusions over remote high latitude regions obviously picking up the aerosol on their way across Canada. In one case subsidence from the stratosphere over Siberia over as many as 15 to 20 days without increase in humidity was observed although a significant amount of Canadian smoke was trapped. These coherent air streams lead to rather straight and rapid transport of the particles to Europe.
Global temperature response to the major volcanic eruptions in multiple reanalysis datasets
Authors: Fujiwara M. , Hibino T. , Mehta S. K. , Gray L. , Mitchell D. , Anstey J.
Published: May 2015

Abstract. Global temperature response to the eruptions of Mount Agung in 1963, El Chichón in 1982 and Mount Pinatubo in 1991 is investigated using nine reanalysis datasets (JRA-55, MERRA, ERA-Interim, NCEP-CFSR, JRA-25, ERA-40, NCEP-1, NCEP-2, and 20CR). Multiple linear regression is applied to the zonal and monthly mean time series of temperature for two periods, 1979–2009 (for eight reanalysis datasets) and 1958–2001 (for four reanalysis datasets), by considering explanatory factors of seasonal harmonics, linear trends, Quasi-Biennial Oscillation, solar cycle, and El Niño Southern Oscillation. The residuals are used to define the volcanic signals for the three eruptions separately. In response to the Mount Pinatubo eruption, most reanalysis datasets show strong warming signals (up to 2–3 K for one-year average) in the tropical lower stratosphere and weak cooling signals (down to −1 K) in the subtropical upper troposphere. For the El Chichón eruption, warming signals in the tropical lower stratosphere are somewhat smaller than those for the Mount Pinatubo eruption. The response to the Mount Agung eruption is asymmetric about the equator with strong warming in the Southern Hemisphere midlatitude upper troposphere to lower stratosphere. The response to three other smaller-scale eruptions in the 1960s and 1970s is also investigated. Comparison of the results from several different reanalysis datasets confirms the atmospheric temperature response to these major eruptions qualitatively, but also shows quantitative differences even among the most recent reanalysis datasets.
Carbon-based phytoplankton size classes retrieved via ocean color estimates of the particle size distribution
Authors: Kostadinov T. S. , Milutinović S. , Marinov I. , Cabré A.
Published: May 2015

Abstract. Owing to their important roles in biogeochemical cycles, phytoplankton functional types (PFTs) have been the aim of an increasing number of ocean color algorithms. Yet, none of the existing methods are based on phytoplankton carbon (C) biomass, which is a fundamental biogeochemical and ecological variable and the "unit of accounting" in Earth System models. We present a novel bio-optical algorithm to retrieve size-partitioned phytoplankton carbon from ocean color satellite data. The algorithm is based on existing algorithms to estimate particle volume from a power-law particle size distribution (PSD). Volume is converted to carbon concentrations using a compilation of allometric relationships. We quantify absolute and fractional biomass in three PFTs based on size – picophytoplankton (0.5–2 μm in diameter), nanophytoplankton (2–20 μm) and microphytoplankton (20–50 μm). The mean spatial distributions of total phytoplankton C biomass and individual PFTs, derived from global SeaWiFS monthly ocean color data, are consistent with current understanding of oceanic ecosystems, i.e. oligotrophic regions are characterized by low biomass and dominance of picoplankton, whereas eutrophic regions have large biomass to which nanoplankton and microplankton contribute relatively larger fractions. Global spatially integrated phytoplankton carbon biomass standing stock estimates using our PSD-based approach yield on average ~0.2–0.3 Gt of C, consistent with analogous estimates from two other ocean color algorithms, and several state-of-the-art Earth System models. However, the range of phytoplankton C biomass spatial variability globally is larger than estimated by any other models considered here, because the PSD-based algorithm is not a priori empirically constrained and introduces improvement over the assumptions of the other approaches. Satisfactory in situ closure observed between PSD and POC measurements lends support to the theoretical basis of the PSD-based algorithm. Uncertainty budget analyses indicate that absolute carbon concentration uncertainties are driven by the PSD parameter No which determines particle number concentration to first order, while uncertainties in PFTs' fractional contributions to total C biomass are mostly due to the allometric coefficients.
Doctoral Programs Outcomes Assessment: An Approach to Assessing Program Inputs, Learning Objectives, and Postgraduation Outcomes
Authors: Carter Shani D.
Published: May 2015

Student learning outcomes assessment is conducted at the undergraduate level for academic departments to determine whether students are meeting learning goals. The assessments do not include course grades; rather, they include measures such as standardized tests or student coursework being rated outside the course by committees. Increasingly, there has been a movement to conduct outcomes assessment on graduate programs as well. This article presents an assessment methodology that can be applied to the special conditions of doctoral programs, which are generally structured very differently than undergraduate and masters’ level programs, and which therefore require different methods of outcomes assessment.
Hiring internationally educated nurses in hospitals: role of competition and resource availability
Authors: Gupta Shivani , Epane Josue Patien , Weech-Maldonado Robert
Published: May 2015

Objective: This study used Porter’s Five Forces Model and the Resource Dependence Theory (RDT) to examine the association of competition and other market factors with the hospital’s decision to hire internationally educated nurses.Methods: A panel design was used comprising a national sample of nonfederal, acute care hospitals (n = 4,116) in the United States. Data, for the years 2008-2012, were derived from American Hospital Association’s Annual Survey and Area Health Resource File. Logistic regression with hospital random effects and state and year fixed effects was conducted to test the above mentioned association.Results: The study findings suggest that hospitals hire internationally educated nurses as a strategy to meet their staffing needs in more competitive and diverse markets. Moreover, hospitals that hire internationally educated nurses are system-affiliated, larger, and see more Medicare patients than those that do not hire them.Conclusions: Findings of this study could help health care managers to understand the influence of market factors on utilization of internationally educated nurses to fulfill their hospitals’ nurse staffing needs. Furthermore, the study findings can inform policymakers in crafting policies on the use of internationally educated nurses as a strategy to address nursing shortages.
Structure of the nucleoli in Angiosperms
Authors: Podbielkowska M.
Published: May 2015

The nucleolus structure in the cells of numerous Angiospermae plants was studied with light microscope. The living material was examined under phase and anoptral contrast. Microscopical observations were also carried out on the material fixed in chrome-formalin or in uranyl-formalin. An occurrence of two structural components of nucleolus was demonstrated: an amorphous ground substance and nucleolonema. Cytochemical analysis have shown that considerable amounts of RNA and acid proteins were located in the amorphous substance while nucleolonema was composed of basic proteins and slight quantities of RNA.
Dobowe wahania deficytu wodnego i ich zależność od czynników klimatycznych [Diurnal changes of water saturation deficit in leaves and their dependence on the climatic factors]
Authors: Czerski J. , Wąsik M.
Published: May 2015

Daily changes in water suction deficit (WSD) in different species of Nicotiana, Digitalis, Calendula, Beta and Brassica were studied. Significant water deficit in the middle of the day was demonstrated for all plants studied.
Mitochondrial nucleoproteins in rye leaves
Authors: Rytel M. , Gołaszewski T. , Szarkowski J. W.
Published: May 2015

Some properties of mitochondrial nucleoproteins sedimentable at 100 000 g, corresponding to the hyaloplasmic ribosomes, were compared with those found for two other subfractions isolated from mitochondria of primary rye (Secale cereale) leaves, the pellet sedimentable at 20 000 g and the supernatant remaining alter 100000 g.
Badania kariologiczne nad dwoma gatunkami rodzaju Sparganium L. [Karyological studies in two species of the genus Sparganium]
Authors: Bijok K. , Adamkiewicz E.
Published: May 2015

The somatic chromosome numbers 2n = 30 for Sparganium neglectum and S. minimum was established. The karyotype of the first species consist of 8 iso- and 7 heterobronchial chromosomes and the reverse is true for the second species. In metabolic nuclei 30 chromocentres are visible.
The anatomical structure of the common fir (Abies alba Mili.) bark. I. Development of bark tissues
Authors: Golinowski W. O.
Published: May 2015

Qualitative and quantitative changes in bark tissues of the fir (Abies alba) connected with the long-term cambium activity were investigated: 1) the development of secondary phloem elements forming the annual ring in different-aged parts of the stem was studied in detail; 2) the terms of formation of the phloem elements were established as well as the duration of the periods of their differentiation and functioning; 3) observations were made of the changes occurring in nonconducting phloem and primary cortex tissues; 4) the course of development of the periderm was studied.
Sugar changes in young seedlings and decotylized embryos of Lupinus luteus
Authors: Ratajczak L. , Mazurowa H.
Published: May 2015

Mobilisation of sugars in Lupinus luteus during the germination and in the early developmental period has been investigated. The embrional decotylized axes of lupin, cultured in vitro on mineral medium with sucrose, accumulate an excessive amount of sugars. The reason seems to be the static character of the medium as compared with the metabolism of the cotyledons.
Effect of GA3 on ribonuclease activity in the embryos and endosperm of spring barley grain in the post-harvest dormancy period
Authors: Rejowski A.
Published: May 2015

The effect of GA3 on ribonuclease activity in the embryos and endosperm of barley seeds was investigated during dormancy and after its end. Incubation of dormancy grain with GA3 stimulated its germination, increased the dry weight of the embryos and their protein content. Ribonuclease activity in seeds treated with GA3 was considerably enhanced. The increase was more rapid and intensive in the embryos than in the endosperm. The action of GA3 was most effective, particularly as regards the endosperm, on grain which had already passed through the stage of dormancy and had reached physiological maturity. This is evidence that the internal factor regulating the process of dormancy exerts a stronger influence on the activity of ribonuclease than does exogenic giberrellic acid.
Effect of white light irradiation on the endogenous growth regulators content in seeds and seedlings of pine (Pinus silvestris L.)
Authors: Kopcewicz J.
Published: May 2015

The increase of gibberellin content and decrease of amount of inhibitors in light irradiated pine seedlings were found. It was also stated that stimulating effect of light on pine seeds germination is correlated with the increase of gibberellin and simultaneous decrease of the inhibitor content. The inhibitor isolated from pine seeds proved to be a compound similar in some properties to abscisic acid.
Studies on pigments of the myxomycete Physarum nudum. I. Absorption spectra of the crude extracts of pigments from plasmodia cultured in continuous light and in darkness
Authors: Rakoczy L.
Published: May 2015

1. Method for extraction and crude separation of the plasmodial pigments of the myxomycete Physarum nudum cultured in light and in darkness were elaborated. 2. By the use of various solvents in the procedure of extraction three pigment fractions were obtained from plasmodia cultured in the dark and four fractions from those grown under continuous light. 3. The absorption spectra of the particular fractions within the UV and visible range were determined.
Upward movement of the domain pattern in the cambium producing wavy grain in Picea excelsa
Authors: Hejnowicz Z.
Published: May 2015

The cambium which produces wavy-grained xylem in spruce differs from normal cambium by a higher frequency of oblique anticlinal divisions and a higher rate of intrusive growth of fusiform initials. Since the orientation, either to the left or to the right, of the divisions and the overlaps achieved by the growting tips is uniform within the areas called domains, the domain pattern of the cambium is reflected in the pattern of grain undulations in the xy1em. The domain pattern moves longitudinally about 0.7 mm during the production of l mm of xylem. A visible expression of the movement is the obliquity of undulation lines on the radial face of the wavy xylem.
Further observations on the activity of Y chromosome heterochromatin in Rumex thyrsiflorus
Authors: Żuk J. , Bolkhovskikh Z.
Published: May 2015

Observation of premeiotic nuclei of plants containing different numbers (from one to five) of Y chromosomes reveal that is such plants prior to meiosis all Y chromosomes are in fuzzy state, while in nuclei of tapetal cells or nuclei from anther stalk the number of big chromocentres is directly correlated with the number of Y chromosomes in given plants. This finding provides a further indication of genetic activity of Y chromosomes in this particular stage of the life cycle (premeiosis). Another indication of genetical activity of Y chromosomes was obtained from analysis of the rate of RNA synthesis in premeiosis. It was found that PMC's in the last premeioitc interphase exhibit a high rate of 3H-uridine incorporation. Thus in PMC's the fuzzy appearance of Y chromosomes coincides with intensive RNA synthesis.
Relationships of Plumiereae (Apocynaceae). III. Based on floral vasculature
Authors: Datta P. C. , Maiti R. K.
Published: May 2015

The study of the floral anatomy of some common Indian species of the tribe Plumiereae (Apocynaceae) supports the conclusions derived from the study of chromosomes and secondary xylem, which are: (1) Holarrhena are distinct from Ervatamia and should be placed in Alostoniinae (Schumann, 1895) and not under Tabernaemontaninae (Bentham and Hooker, 1876). (2) Different subtribes possess distinctive features; and, therefore, the classification into subtribes is justified. (3) Tabernaemontaninae are the most primitive subtirbe from which the others can be derived. (4) Alstoniinae are heterogeneous and are composed of different evolutionary lines. (5) The genus Plumeria stands isolated in tribe Plumiereae and needs separation as a new taxon.
Fine structure of lipotubuloids (elaioplasts) in Ornithogalum umbellatum in the course of their development
Authors: Kwiatkowska M.
Published: May 2015

Among the most important changes in the fine structure of lipotubuloids, observed in the course of their development cycle, belong: 1) the appearance in ageing lipotubuloids of autolytic vacuoles, in which hydrolytic enzymes are present; 2) the disappearance of the microtubules forming a network and interconnecting the osmiophilic granules, which precedes the dispersion of these granules agglomerated in lipotubuloids.
Fine structure of kinetin-treated protonema and kinetin-induced gametophore buds in Funaria hygrometrica
Authors: Młodzianowski F. , Szweykowska A.
Published: May 2015

Besides occasional hypertrophy of grana and disintegration of stroma thylakoids occurring in some chloroplasts, no significant changes were found in ultrastructure of typical protonema cells treated for six days with kinetin. On the other hand, the fine structure of cells in kinetin--induced gametophore buds differed much from that of the protonema cells and showed characteristics of cells of with high metabolic activity and high division rates. The results indicate that cytokinins enhance development and differentiation in the protonema by activating only some of its cells, whereas the others remain unchanged or show symptoms of destruction and ageing. This is supported by the fact that in the presence of chloramphenicol, which prevents bud induction, kinetin acts synergistically with the inhibitor in producing degeneration and destruction of chloroplasts.
Effect of water extract from leaves of Nerium oleander L. on mitosis
Authors: Tarkowska J. A.
Published: May 2015

The effect of water extract from leaves of Nerium oleander L. on the mitosis in meristematic cells of Allium cepa L. root tips has been studied. Observations were made on the changes during incubation and postincubation. Significant disturbances were observed in the development of the mitotic spindle leading to the formation of polyploid and hypoploid nuclei capable of further division. Substances contained in the water extract, and causing the disturbances, are water soluble glycosides. Introductory observations under an electron microscope indicate that the glycosides desorganize the continuous fibres of the spindle which can be considered as the direct cause of the observed disturbances.
The influence of gibberellin on the level of soluble protein and activities of some hydrolases in corn seedlings
Authors: Masłowski P. , Masłowska H.
Published: May 2015

The effect of gibberellin on the qualitative and quantitative composition of soluble proteins and the activity of Mg++ dependent and Na+-K+ -stimulated ATPase, RNase and peptidase in five days old maize seedlings were investigated. The chromatography of soluble proteins on DEAE cellulose gave seven fractions. All these fractions had ATPase and RNase activities. Gibberellin stimulated most strongly ATPase, to a smaller degree RNase and it did not effect the activity of peptidase.
Acrylamide gel electrophoresis of proteins, acid phosphatases and RN-ases from three potato varieties
Authors: Kubicz A. , Wieczorek E. , Morawiecka B.
Published: May 2015

Studies on variety differences in the protein and acid phosphatase patterns as well as ribunuclease activity distribution were carried out by disc electrophoresis on saline extracts of three varieties of the potato Solanum tuberosum (L.). The protein bands varied in number, position and relative abundance. One main zone of the acid phosphatase activity was detected consisting of 2-3 electrophoretically different bands. Variety differences were concerned with the number and relative abundance of these bands. RNase activity was detected in 4 main zones, in some of them additional subbands were visible. Differences between the three examined varieties were reflected in the occurence of the particular activity zones or their subbands.
Zespół Carici elongatae-Quercetum – dębniak turzycowy [Association Carici elongatae-Quercetum]
Authors: Sokołowski Aleksander W.
Published: May 2015

In the region of north-eastern Poland forests made up of Quercus robur with a very small amount of other species occur. Because of the specific species composition of the trees and herbs and the particular soil conditions the author proposes to consider these forests ass a new association called Carici elongatae-Quercetum.
Badania mieszańców w rodzaju Trifolium L. IV. Cytogenetyka mieszańca Trifolium repens L. × T. isthomocarpum Brot. [Investigations on hybrids of the genus Trifolium L. P. IV. Cytogenetics of the cross T. repens L. × T. isthomocarpum Brot.]
Authors: Kazimierski T. , Kazimierska E. M.
Published: May 2015

Interspecific F1 hybrid between Trifolium repens (2n = 32) and T. isthomocarpum (2n = 16) was obtained. The hybrid is sterile and its disturbed meiotic divisions are described. It is suggested from cytogenetic evidence that one of the genomes of T. repens is similar to the genome of T. isthomacarpum.
Effect of adenine on the synthesis of purine derivatives in wheat seedlings
Authors: Rybacka Hanna
Published: May 2015

The effect of adenine and other purine derivatives on the "de novo" purine synthesis was investigated in young wheat schoots. Adenine, adenosine and AMP inhibited strongly this biosynthesis, whereas hypoxanthine had no effect. The incorporation of each of the used precursors; [l-14C] glycine, [14C] formate and [14C] carbonate was inhibited by adenine in the same extent.
Callose in compression wood tracheids
Authors: Brodzki P.
Published: May 2015

A study of 20 gymnospermous species has shown that in most of them callose occurs in the helical checks of the S2 layer of cell walls in the compression wood tracheids. It is suggested that owing to its swelling properties callose plays a part in the longitudinal extension of compression wood.
Activities of enzymes connected with IAA oxidation in cucumbers of various sex types
Authors: Maciejewska-Potapczykowa W. , Rennert A. , Milewska E.
Published: May 2015

Activity of peroxidase, cqtalase, and IAA-oxidase in flower buds, stems and stem callus cultures derived from four pure genetic lines of Cucumis sativus L., i.e. male, monoecious, female and hermaphrodite was determined. The activities of all enzymes in flower buds and callus cultures are considerably higher in the female lines then in male ones. IAA-oxidase activity is the highest in female line, independently of the type of plant material under examination. The activities of the remaining two enzymes depend on the type of tissue or organ under examination.
The effect of various cytokinins and other factors on the protonemal celi divisions and the induction of gametophores in Ceratodon purpureus
Authors: Szwejkowska A. , Korcz I. , Jaśkiewicz-Mroczkowska B. , Metelska M.
Published: May 2015

The cytokinins specifically induce formation of gametophore buds in the protonema of Ceratodon purpureus. The responsein this species is less sensitive than in Funaria hygrometrica, but is independent of light. The cytokinins also stimulate protonemal cell divisions, this response, however, is not specific and affected by many other factors.
The ratio of K to Ca in thalli of several species of lichens occurring on various trees
Authors: Kuziel Stanisława
Published: May 2015

The per cent contents of K and Ca in 7 species of lichens and in the bark: of trees and extracts from this bark were determined. The ratio K : Ca was calculated. In the particular species of lichens collected from the tree the K : Ca ratio varies from 0.05 to 4.93. In the thalli of one species collected from various species of trees the content of cations varies, but the K: Ca ratio is more or less constant in particular species.
The effect of ultrasonic energy on the separation of cytoplasmic RNA fractions
Authors: Tyrawska-Spychałowa D. , Adamczyk Z. , Halicz B.
Published: May 2015

Plant tissue -4 days old germs of Zea mays and Pisum sativum were subjected to ultrasonic energy using generator with a constant frequency of 800 kHz. RNA was isolated by Mieczyński’s modification of the method described by Georgiev. Preparations of RNA were separated by electrophoresis on the coloured agar-gel. Depending on the degree of ultrasonication changes in three fractions of RNA: A1 - 28 S, A2 - 18 S and A3 - 4 S were observed
Effect of vanadium on nitrate reductase activity in tomato leaves
Authors: Buczek J.
Published: May 2015

The activity of nitrate reductase in cell-free extracts from tomato leaves is completely inhibited by 100 μM NaVO3 or VOCl2. In experiments in vivo vanadium ions inhibit the activity of the enzyme in 50 to 60 per cent. Addition of l mM vanadium to the medium on which tomato seedlings are grown causes after 24 h almost complete inhibition of nitrate reductase activity in cell-free extracts of the enzyme. Inhibition with vanadium may be abolished in experiments in vitro if the extract is treated with a rather concentrated EDTA solution or Sephadex G-25. The data obtained in this study indicate that vanadium ions in relatively low concentrations inhibit the activity of nitrate reductase in tomato seedlings both in vivo and in nitro.
Disc electrophoretic investigation of Coffea arabica and Coffea canephora - general protein and malate dehydrogenase of cotyledonary leaves
Authors: Oliveira A. R. , Payne R. C. , Fairbrothers D. E.
Published: May 2015

Disc electrophoretic data for malate dehydrogenase and general protein from cotyledonary leaves revealed detectable differences among Coffea species, varieties and cultivars.
Phosphatase activity of Poa pratensis seeds. I. Preliminary studies on acid phosphatase II
Authors: Lorenc-Kubis I. , Morawiecka B.
Published: May 2015

Acid phosphatase (EC 3.1.3.2) was extracted with 0.1 M sodium acetate buffer pH 5.1 from Poa pratensis seeds, and separated into three fractions by chromatography on DEAE cellulose. The highest activity was found in fraction Il-b (acid phosphatase II). The activity of the enzyme was optimal at pH 4.9. It hydrolyzed p-nitrophenyl phosphate most readily among the various phosphomonoesters examined. Acid phosphatase II showed also a high activity toward β-naphtyl phosphate and phenyl phosphate, very low activity towards β-glycero phosphate, 5'-GMP and no activity with glucose-1 phosphate. The enzyme was inhibited by Ca2+ and fluoride, but activated by Mg2+. EDTA had no influence on the activity of the enzyme.
Effect of IAA on growth, organogenesis and RNA metabolism during the development of Cichorium intybus root explants cultured „in vitro"
Authors: Gwóźdź E.
Published: May 2015

The effects of 3-indolylacetic acid (IAA) on growth, organogenesis, RNA content, RNase activity and MAK elution profiles during the development of chicory root explants cultured in vitro were investigated. It was found that the intensive callus growth in the presence of IAA was accompanied by an increase in the RNA content, with simultaneous decrease of RNase activity. Fractionation of RNA by MAK column chromatography showed that the high content of RNA in the callus under the influence of IAA was due to an increased accumulation of the ribosomal fraction of RNA mainly. Experiments with actinomycin D demonstrated that this antibiotic abolished both the auxin-induced callus growth and the inhibitory effect of IAA on bud formation. No significant inhibition of spontaneous bud formation under the influence of actinomycin D was observed. The possible relationship between the IAA-affected morphogenetic processes and RNA metabolism is discussed.
Incorporation of radioactive products of photosynthesis into lignin and cellulose of Scots pine (Pinus sihestris L.) seedlings
Authors: Góral Igor
Published: May 2015

Distribution of radioactive photosynthetic products as well as their utilization in biosynthesis of lignin and cellulose in one-year-old pine seedlings was investigated at different growth stages. It was found that time of metabolization and the rate of photosynthetic products incorporation into lignin and cellulose depends on the organ and -on the kind of polymer synthetized.
Iivestigations on hybrids in the genus Trifolium L. V. Fertility and cytogenetics of the hybrid Trifolium nigrescences Viv. x T. isthomocarpum Brot.
Authors: Kazimierski T. , Kazimierska E. M.
Published: May 2015

T.nigrescens (2n = 16) crosses with T .isthomocarpum (2n = 16) reciprocally. The viability of hybrid seedlings depend from the direction of the cross. At the time of diakinesis and metaphase I the average chromosome figures per PMC's was 7.014II, 0.005III, 0.435IV and 0.209I. For one half of the PMC's in the metaphase I the typical chromosome arrangement was 8II. The F1 plants was almost completly sterile. The causes of viability of hybrid seedlings depending on the direction of the cross, and the sterility of hybrid plants, are discussed.
Megasporogenesis and development of the embryo sac in the Palestine variety of Trifolium alexandrinum L.
Authors: Krupko S.
Published: May 2015

The structure and development of the embryo sac in Trifolium alexandrinum (Palestine variety), are very similar to that in Trifolium pratense. The embryo sac of Trifolium alexandrinum is monosporal, has eight nuclei and is of the Polygonum type. The Palestine variety of Trifolium alexandrinum can be autogamous.
Domain pattern in the cambium of young Platanus stems
Authors: Krawczyszyn J.
Published: May 2015

In the vascular cambium of Platanus Z and S domains appear in the course of formation of the first annual ring. Their arrangement is connected with the division of the stem into nodes and internodes. In each node a domain of Z and of S type occurs. The longitudinal boundaries between them run along the middle leaf trace and on its opposite side, and the transverse boundaries lie in the nodes. Z-type domains are found on the right below the base of the nearest upper leaf, and S-type domains on the left. As the young cambium forms further rings, the size and shape of the domains changes.
Taxonomic relations of Plagiomnium affine (Funck.) Kop. and P. elatum (B.S.G.) Kop
Authors: Mamczarz H.
Published: May 2015

A taxonomic study of two species of Mniaceae family (Mosses) was made based upon the microscopic features of specimens from extensive collection in Northern and Eastern Poland. The examined species of the genus Plagiomnium are treated in accordance with the new bryological classification.
Free amino acids in the panicles of Dactylis glomerata in the course of their development
Authors: Dąbrowska T.
Published: May 2015

The composition of free amino acids and proline content in various parts of Dactylis glomerata panicles at different stages of their development were determined by paper chromatography and electrophoresis. The proline level in the spikelets was found to change widely in the course of their development. The results are discussed with reference to the role of proline in the nitrogen metabolism of plants.
Concentration of heavy metals - iron, manganese, zinc and copper in mosses
Authors: Czarnowska K. , Rejmont-Grochowska I.
Published: May 2015

The iron content in gametophytes of Aulacomnium palustre. Climacium dendroides, Catharinea undulata is 5—10 times higher than in vascular plants. The manganese, zine and copper content is 2-3 times higher than in vascular plants. The content of these elements in sporophytes of Catharinea undulata is approximately the same as in vascular plants. The accumulation of the investigated metals takes place mainly in the protoplasts of the chlorophyll cells of gametophyte leaves. A weakly acid pH of the medium favors accumulation. No distinct difference was found between the Fe2O3 content in mosses and the soil.
Soluble nitrogen compounds in tillering nodes and roots of Dactylis glomerata
Authors: Dąbrowska T.
Published: May 2015

A characteristic is given of the low molecular weight fraction of nitrogen compounds in tillering nodes and roots of the grass Dactylis glomerata in spring and in autumn. It was found that in vegetative storage organs of Dactylis glomerata glutamic acid with glutamine, aspartic acid with asparagine, alanine and arginine play important roles in the storage of nitrogen. From the free amino acids pool of the tillering nodes and roots item amino acids in crystalline form were isolated and identified.
Effect of the change of nitrogen source on photosynthesis and respiration of Scots pine (Pinus silvestris L.) seedlings
Authors: Zajączkowska J.
Published: May 2015

Rates of photosynthesis and respiration of Scots pine seedlings, grown in water culture under conditions of nitrogen deficiency and supplied with nitrogen in ammonium or nitrate form, were investigated. Besides, the rates of photosynthesis and respiration of the seedlings were measured, after changing the form of supplied nitrogen. A rapid and different response of nitrogen deficient seedlings was found independent on the form of supplied nitrogen. The investigations also showed a change in rates of photosynthesis and respiration of seedlings after changing the form of nitrogen.
Structure of plant cell nucleus viewed by scanning electron microscopy
Authors: Wodzicki T. J. , Brown C. L.
Published: May 2015

The three-dimensional structure of the nucleus ta meristematic and differentiated phloem ray parenchyma cells of shortleaf pine (Pinus echinata Mili.) is viewed by scanning electron microscopy. The fixed and dehydrated plant tissues were freeze-fractured in absolute ethanol and dried by the critical point method. Some of the features observed in the fractured nuclei are aggregates of chromatin some of which possess a spiral orientation, the attachment of chromatin to the nuclear envelope, and small canals in the fractured envelope probably representing nuclear pores.
Sugars in Iris pseudoacorus L. seeds
Authors: Maciejewska-Potapczyk W. , Saniewski M. , Pełczyńska M.
Published: May 2015

Qualitative and rough quantitative analyses of sugars occuring during the successive developmental phases in two poles - micropylar and chalasal - of the seeds of Iris pseudoacorus L. were made. Comparing the sugar dynamics of the respective developmental phases distinct differences were found in mature and immature seeds. Soluble polysaccharides being an initial form of accumulation do not occur in ripe seeds. No differences were found in the contents of insoluble sugars in chalasal and micropylar poles. The endoperm and the seed coat differ in the level of some sugars.
Assimilatory pigments, photosynthetic activity and ultrastructure of chloroplasts of the variegated-leaf chimera of Acer platanoides L.
Authors: Więckowski S. , Ficek S.
Published: May 2015

The assimilatory pigment composition, photosynthetic activity and ultrastructure of chloroplasts were studied in the chlorophyll - deficient chimera of Acer platanoides L. Part of the crown of this chimera is a virescent mutant with variegated leaves. It was found that there exists no qualitative difference in the pigment composition between normal and variegated leaves. The accumulation of chlorophyll in the mutated part is more delayed that the accumulation of carotenoids. The photosynthetic rate on a chlorophyll basis is much higher in variegated than in green leaves. This difference gradually falls off with development. In the early spring, chloroplasts from the yellow spots of leaf blade have no lamellar system but only many vesicles are dispersed in the stroma. Occasionally also a single granum consisting of a few thylakoids occurs in the stroma. At the end of summer chloroplasts from yellow spots of variegated leaves possess a poorly developed lamellar system.
The role of vanillin and p-coumaric acid in the growth of Scotch pine seedlings
Authors: Michniewicz M. , Galoch E.
Published: May 2015

It was stated that vanillin and p-coumaric acid used at concentrations 10-8-10-5M stimulated the growth of pine seedlings. Most effective were these substances used at concentration 10-7M. Both phenolic compounds stimulated the elongation, fresh and dry weight in very young seedlings (up to 3-4 weeks) and increased the fresh and dry weight only in older ones (7 weeks). The stimulation of growth processes in pine seedlings treated with vanillin and p-coumaric acid coincided with the increase of auxins in roots and with the decrease of free gibberellins in these plant organs. Neither vanillin nor p-coumaric acid influenced the level of ABA-like inhibitor both in the shoots and roots of pine seedlings.
Structure of anther heads in some Trifolium L. species
Authors: Kazimierski T. , Kazimierska E. M.
Published: May 2015

The species of the genus Trifolium differ by the number of pollen sacs in stamen heads. Some have only two, other four and in some species there arę two, three or four pollen sacs. The opinion of some authors (Schnarf 1931, Davis 1966) that from this point of view this genus is uniform is wrong. There is some dependence between the chromosome number (2n) and the number of pollen sacs. For two species - T. carmeli and T. desvauxii - the chromosome numbers 2n=14 were established for the first time.
Variability of the Polish species of the genus Riccardia (Hepaticae, Aneuraceae). II. Culture material
Authors: Menelak Maria
Published: May 2015

Detailed investigations both numerical and experimental were performed on 38 samples of populations of three species of the genus Riccardia from the territory of Poland: R. latifrons, R. palmata and R. chamedryfolia. The intraspecific variability was found to be of genetic character in the first two species. The results gave ground to describe two new varieties: R. latifrons var. minor and R. palmata var. maior.
Syntaxonomic position of Hydrocharitetum morsus-ranae van Langendonck 1935
Authors: Podbielkowski Z. , Tomaszewicz H.
Published: May 2015

The syntaxonomic appurtenance of Hydrocharitetum morsus-ranae is discussed. On the basis of data concerning its ecology, social correlates and its position in succession, the authors arę against including this association into the class Lemnetea. They would rather be inclined to classify it to the alliance Nymphaeion, class Potametea.
Influence of sulphur dioxide on chlorophyll content and catalase activity in some chosen lichen species
Authors: Kuziel Stanisława
Published: May 2015

The influence of SO2 on changes in catalase activity and in chlorophyll content were investigated under laboratory conditions in several lichen species and in maize. In all the plants examined the chlorophyll content and catalase activity decreased after treatment with SO2 as compared with that in the control plants.
The effect of water saturation deficit on the volume of intercellular space in laeves
Authors: Czerski J. , Sosińska A. , Kozłowska Z.
Published: May 2015

The volume of intercellular spaces in leaves at various stages of water saturation was determined by method of Czerski (1964, 1968). The investigation were performed with the following plant species: Vicia faba L., Nicotiana tabacum L. var. rustica, Solarium tuberosum L. var. Flisak, Helichrysum bracteatum Wild., Bmssica napus L. var. oleifera, Beta vulgaris L. var. saccharifera.
Preliminary studies on ribonucleases from Poa pratensis seeds
Authors: Lorenc-Kubis Irena , Morawiecka Bronisława
Published: May 2015

Ribonuclease was extracted from Poa pratensis seeds with 0.1 M acetate buffer, pH 5.1, and then precipitated with alcohol. The enzyme was separated into 5 fractions (I-V) after chromatography on DEAE-cellulose at pH 5.1. The enzymes were stable at 50°C, at pH 7.1. The activity of ribonucleases I, II, III and V were optimal at pH 7.1-7.3, and that of ribonuclease IV at pH 8.1. Ali enzymes were inhibited by Ca2+ and EDTA. Mg2+ inhibited the activity of ribonucleases II, III, IV, and had no influence on that of ribonucleases I and V. Ribonucleases IV and V showed only one activity band in disc electrophoresis, whereas ribonucleases, I, II and III were found to be heterogenous.
Metabolism of hypoxanthine in wheat shoots
Authors: Rybicka Hanna
Published: May 2015

The incorporation of [14C] glycine and [8-l4C] hypoxanthine to some purine derivatives in overground parts of wheat seedlings was studied. It was found that adenylic acid could be synthesized from glycine and also from free hypoxanthine and in both processes inosinic acid is an intermediate metabolite.
Variety-specificity of soluble proteins of potato tubers
Authors: Czupryn Marta , Toczko Kazimierz
Published: May 2015

Separation of soluble tuber proteins from six potato clones and twelve varieties cultivated in Poland has been accomplished by disc electrophoresis. It was found that electrophoretic pattern was unique for a given clone or variety. Data obtained confirm results of the other authors for the other varieties and indicate that electrophoretic analysis of potato tuber proteins can be a useful method for taxonomic studies. Such analysis however cannot be used for genetic research since no correlations were found between electrophoretic patterns and genetic origin of respective clones and varieties.
Chloroplast arrangement as a factor of photosynthesis in multilayered leaves
Authors: Lechowski Z.
Published: May 2015

The dependence of photosynthesis on arrangement of the chloroplasts in Ajuga reptans and Syringa vulgaris differing in the ability of chloroplasts translocation was studied.
The ultrastructure of chloroplasts in variegata irregulare mutants of garden petunias (Petunia hybrida hort. superbissima)
Authors: Muszyński Stanisław
Published: May 2015

The ultrastructure of mutated chloroplasts in tetraploid garden petunias (Petunia hybrida hort. superbissima) was analyzed by electron microscopy. The formation of grana structure is inhibited after secondary thylacoids start forming. Rapid dezintegration of the structure is observed. It is suggested that a substance responsible for photostabilization of grana structure is lacking.
Autoradiographic study of 3H colchicine binding in synchronously dividing cells of antheridial filaments of Chara vulgaris L. during successive stages of development
Authors: Olszewska Maria J.
Published: May 2015

The intensity of 3H colchicine binding was investigated autoradiographically as a marker of an amount of the microtubule subunits during interphase and mitosis in synchronously dividing 4-, 8-, 16- and 32-celled antheridial filaments of Chora vulgaris. These cells were incubated with 3H colchicine in vivo or after fixation. The radioactivity of cells in the successive generations of antheridial filaments diminishes, similarly as the surface of cytoplasm and intensity of protein synthesis. During interphase the intensity of 3H colchicine binding is proportional to the increase of cytoplasmic surface; the highest increase of radioactivity occurs in G2. During mitosis the increase of radioactivity continues in prophase; the highest radioactivity was found in prophase and telophase cells, the lowest in anaphase cells; a comparatively pronounced radioactivity is visible in metaphase. Radioactivity in posttelophase, as estimated per one daughter cell, is approximately one half of that of the mother cells in telophase of the previous generation suggesting the reutilization of microtubule proteins in the next mitotic cycle.
Calcium-Magnesium salt of saponins from bird's foot trefoil seeds (Lotus corniculatus L.)
Authors: Górecki Piotr M. , Jurzysta Marian
Published: May 2015

A calcium-magnesium salt of saponins was isolated from bird's foot trefoil seeds with a yield of 0.04%. The salt contained: 1.37% - Ca and 0.04% - Mg. The saponin salts were deionized on IR-120 Amberlite and free crystalline saponin was obtained. In both cases the presence of one major component and of three trace ones was found, using TLC. In acid hydrolysates of the saponin salts and of the free saponin the following sugars were identified: rhamaose, xylose, glucose, galactose, glucuronic acid. From among aglycones soyasapogenols B, C, traces of E, and of one unidentified in both cases were found. The Ca-Mg salt obtained seems to be a natural form of saponins in bird's foot trefoil seeds.
Tussilago farfara L. - a plant relatively resistant to industrial air pollution
Authors: Świeboda Maria , Brunarska Zofia
Published: May 2015

Tussilago farfara L. is a species highly resistant to the fumes emitted by the factory of silicophosphate fertilizers and to other kinds of industrial air pollution. The resistance of this species results from the wide ecological amplitude and characteristic anatomical structure of the leaves of this plant.
Gametogenesis and pollination processes in Ornithopus pinnatus (Mili.) Druce in reference to flower bud development
Authors: Wojciechowska Wanda
Published: May 2015

It was found, that in Ornithopus pinnatus the development of microspores and pollen grains is not simultaneous in the two stamen whorls and it precedes the development of the embryo sacs. The pollen grains attain the highest germination capacity before the bud is open, when the embryo sacs arę mature.