bluuebunny/crossref_metadata_2025 huggingface dataset:
In vivo and in vitro pollen maturation in Lilium: influence of carbohydrates
Authors: Clement Christophe , Al-Awad Daniel , Audran Jean C.
Published: April 2013

The purpose of this study was to develop a protocol for in vitro conform pollen maturation, as a model to study the involvement of carbohydrates on pollen maturation in Lilium. In vivo and in vitro pollen maturations were followed and compared by transmission electron microscopy, and several in vitro parameters were tested in terms of carbohydrate physiology. In vivo, pollen maturation was initiated at the vacuolated microspore stage, and consisted of two successive phases. The first phase was characterized by reactivation of microspore organelles, followed by microspore mitosis, starch synthesis and vacuole breakdown. During the second phase, starch was progressively degraded whereas lipid and phytine reserves accumulated. In vivo, pollen maturation occured within 14 days and pollen germination rate was 73.6 ± 2.2%. We then attempted to realise in vitro pollen maturation starting from the vacuolated microspore stage. The best results were obtained with flower buds cultivated at 26oC, in 100 µmol/m2/s light, with a 16h/8h photoperiod on a modified Heller's medium supplemented with NAA (10-2 mg/l) and sucrose (M/6). In these conditions, pollen maturation occured within 7 days only. In vitro matured pollen is cytologically comparable to in vivo developed pollen grains and the germination rate was 72.4 ± 3.7%. When flower buds were cultivated in the dark, the germination rate decreased, but this could be compensated by providing high sucrose concentrations (1M) in the medium. Further, photosynthesis inhibitors had the same effect on pollen maturation than the darkness, strongly suggesting that photosynthesis occurs in the flower bud and is important for pollen maturation in Lilium.
Pollen wall structure in Anigozanthos viridis (Haemodoraceae)
Authors: Rowley John R. , Rowley Joanne S.
Published: April 2013

The exine of Anigozanthos viridis Endl. pollen is divided into two zones by a plane which has been referred to as a"commissural line"; in our results we refer to it as a junction plane - a more apt description. Following young stages there is a pronounced reduction in thickness of the inner exine, probably due to stretching of the exine without the addition of new material as development progresses. We describe the fibrillar zone under the exine in microspores as oncus-like. Since this onciform zone precedes microspore mitosis and intine formation the fibrillar zone is divided into two layers in mature pollen an onciform part and the intine proper - it is not a two layered intine.
Quantitative evaluation of the pollination process of european larch (Larix decidua mill.) in seed orchard
Authors: Križo Milan , Slobodník Branko
Published: April 2013

The pollination of European larch (Larix decidua MILL.) was investigated in the seed orchard Dolné Mlynárovo (Low Tatra Mts, Central Slovakia) during years 1991-1993. The pollen in the air was captured on horizontally and veritically placed microscopical glasses in different areas of the seed orchard. After the pollination period, ovules were isolated from the fermale strobili in order to find out the percentage of the pollinated ovules and number of the pollen grains per collecting apparatus. Approximately 140 pollen grains per square centimeter on average were captured on the vertically placed microscopical glasses in 1991, up to 400 in 1992, and only 40 in 1993. The most rapid course of the pollination was observed in 1991. Most pollen grains (in some cases more than 2,000 per square centimeter) were intercepted on the 5th and 7th day of observation and in next days the numbers of captured pollen were significantly lower. In 1992 the pollination period was much longer and more harmonious. This fact is probably associated with stable temperatures and small amount of precipitation (unlike to 1991). When comparing the number of pollen grains on horizontally placed microscopical glasses, approximately 25 pollen grains on average were captured in 1992, 6 in 1991, and only 2 per square centimeter in 1993. Days with the maximum numbers of intercepted pollen did correspond with the maximum values obtained from the vertically placed interceptive glasses. Almost all of analyzed ovules were pollinated in 1992 and up to 27 pollen grains were found on their pollen collecting apparatus in some extreme cases. In 1991 the situation was similar to 1992 (more than 85% ovules pollinated), but in 1993 only 40-85% ovules were pollinated (depending upon the grafted plants and different parts of the crowns) and only 1-3 pollel grains were found in the majority of pollinated ovules.
Boron concentration gradient in the endosperm and embryo during ovule development in Clivia miniata
Authors: Reczyński Witold , Ryczkowski Marian , Czaja Urszula
Published: April 2013

Research on boron concentration gradient in the endosperm and embryo of Clivia miniata Regel ovules is a continuation of investigations on polar distribution of several compounds in the developing ovule. The polar distribution of chemical compounds in the ovule might constitute one of the factors determining embryogenesis. It was found that: a) there occured a chalaza-micropyle gradient of boron concentration in the endosperm during the exponential phase of embryo growth (age of ovules - 50 to 120 days); boron concentration in the endosperm increased from 12.13 to 23.71 µg g-1 fr.wt. (micropylar part) and from 13.58 to 28.42 µg g-1 fr.wt. (chalazal part); the embryo elongated towards the chalazal part of the ovule, i.e. towards higher boron concentration in the endosperm; b) in the embryo a reversed gradient of boron was detected: a higher concentration in the micropylar part (decrease from 127.29 to 61.78 µg g-1 fr.wt.; ovules 86-123 days old), a lower one in the chalazal part (decrease from 99.47 to 53.16 µg g-1 fr.wt.; the exponential phase of embryo growth).
Reproductive strategy in the Ranunculus auricomus complex (ranunculaceae)
Authors: Izmaiłow Romana
Published: April 2013

A preliminary study of reproductive strategy was carried out on plants representing four cytotypes of the Ranunculus auricomus complex. Diploid plants reproduce sexually, triploids, tetraploids and hexaploids have an apomictic mode of reproduction (apospory combined with pseudogamy). Some morphological characters of the plants connected with reproduction were analyzed at various phases and compared in two successive seasons. The following characters were estimated at the individual level: number of ovules and primary pollen grains per plant, pollen viability, pollen-ovule ratio, number of achenes per plant and their germinability, seed-ovule ratio. Most of data characteristic of reproductive strategy were calculated according to the formulae proposed by Urbańska (1989, 1990). Apomictic cytotypes have both a significantly lower pollen viability and seed-ovule ratio (the lowest values in triploids) than sexual diploids.
Number of nuclei, mitotic activity and cell length in Cladophora sp thallus treated with cadmium and chromium
Authors: Krajewska Monika
Published: April 2013

Cladophora sp., a fresh water, filamentous, multi-nucleate alga growing 16 days in the presence of cadmium and chromium at concentrations 10-4 10-8M was the subject of the experiment. Chromium ions reduced the number of nuclei and mitotic activity, and disturbed the correlation between cell length and number of nuclei, more than cadmium ions. Moreover, both tested metals caused the disappearance of cells with numerous nuclei with time of the culture. Only during the first (1-4) days of culture for both metals the concentration of 10-4M and especially of 10-8M increased the number of nuclei, mitotic index and the length of cells. Apical cells were more sensitive to metals than other thallus cells.
Light microscopical study of endosperm formation in Brassica napus L.
Authors: Van Lammeren A. A.M. , Kieft H. , Ma F. , Van Veenendaal L. H.
Published: April 2013

The cellularization of the endosperm of Brassica napus was investigated with light microscopy after embedment in Technovit 7100. The microtubular cytoskeleton was visualized by immunofluorescence techniques after embedment in butyl methyl metacrylate (BMM). The analyses of sectioned seeds, sampled at various developmental stages, revealed that the endosperm has a nuclear phase up to the early heart shaped stage of the embryo. From the heart shaped stage onwards cells and alveoli are formed in the endosperm. The cellularization of endosperm was preceded by alveolus formation except in the region surrounding the embryo suspensor and in the chalazal zone of the embryo sac where the nuclear endosperm vacuolated and cell walls were formed all around the nuclei. Alveolus formation only occurred when nuclei had attained a dense distribution in the layer of cytoplasm aligning the wall of the central cell. When nuclei divided within the alveoli, cell plate formation resulted in the formation of mononuclear endosperm cells along the embryo sac wall. When the walls of the alveoli grew towards the centre of the embryo sac, alveoli regularly closed leaving space for enlargement of the remaining alveoli. In this way endosperm cells enlarged going from the periphery to the central area of the embryo sac. The microtubular cytoskeleton was visualized in the nuclear, alveolar and cellular endosperm. The pattern observed, showed that the organization and function of the microtubular arrays was as generally found during endosperm development.
Carotenoids in the cells of the alga Trentepohlia gobii Meyer
Authors: Czeczuga Bazyli , Maximov Oleg M.
Published: April 2013

Column-, and thin-layer chromatography revealed the presence of the following carotenoids in the cells of the species Trentepohlia gobii Meyer from cobbles in the river Urmi in the Badzhal mountains of Khabarovsk Territory in the Far East: ß, ß-carotene, ß, ε-carotene, ß, ß-carotene-2-ol, ß, ε-carotene-2-ol, ß, ß-carotene-2, 2'-diol, 5,6-epoxy-5,6-dihydro-ß, ß-carotene-2-ol, 5,6-epoxy-5,6-dihydro-ß, ε-carotene-2-ol and 5,6,5',6'-diepoxy-5,6,5',6'-tetrahydro-ß, ß-carotene-2,2'-diol.
Interaction between cadmium and iron. Accumulation and distribution of metals and changes in growth parameters of Phaseolus vulgaris L. seedlings
Authors: Siedlecka Anna , Krupa Zbigniew
Published: April 2013

The interaction between cadmium, one of the most toxic heavy metals, and iron, an essential plant nutritional element, was investigated in Phaseolus vulgaris L. (cv. Słowianka) seedlings. The interaction was externally induced by changing the content of both metals in the nutrient medium. Under iron deficiency conditions (0 and 0.5 of normal dose of this element), the toxic effects of cadmium on plant growth parameters, like fresh and dry weight accumulation, primary leaves area, etc., were generally much more pronounced than under normal iron supply. At normal and excess iron supply (1, 2 and 4 doses) cadmium diminished iron accumulation in roots and primary leaves, but on the other hand excess iron decreased cadmium level, preventing plants from extreme toxicity of very high cadmium concentrations in the growth environment. It is to be noted that iron is classified also as a heavy metal, and its excess may become toxic, e.g. decreasing root dry weight or diminishing leaf area, especially at the highest dose. The detoxication role of iron against cadmium, and possibly other toxic metals is, however, limited to concentrations of this element in the nutrient solution which themselves are not toxic for the organism.
Effect of iron deficiency stress on leaves movements and electrical potentials in mimosa (Mimosa pudica L.)
Authors: Ślesak Edward
Published: April 2013

The aim of the studies was to trace the motorical and electrical activity of the mimosa (Mimosa pudica L.) grown under conditions of iron deficiency. The speed of leaf folding was measured (motorical activity) and the action potential induced with thermic and light stimuli and turgorin (electrical activity was recorded). It was found that the iron deficiency caused acidification of medium and the maximum of the process coincided with the period when the young leaves were turning green. Chlorotic mimosa leaves, not detached from the plant, showed an increased motorical activity. Motorical and electrical activity of the leaves were inhibited by an inhibitor of the plasmalemma redox systems - quinacrine, and stimulated by blue light. Leaf movement factor - turgorin - caused a hypersensitivity of chlorotic plants. It follows from the studies that the observed effects resulted from the adaptation of mimosa to the iron stress. The adaptation was a result of formation of new plasmalemma redox systems (turbo-reductase), responsible for maintaining high energy levels in the cells.
Sulfite inhibition of sucrose transport into vacuoles of cottonwood leaves
Authors: Lorenc-Plucińska Gabriela
Published: April 2013

The mechanism of sucrose transport and the influence of various concentrations of sulfite on its activity was studied in the mesophyll vacuoles isolated from cottonwood (Populus deltoides Bartr. ex Marsh) leaves. Kinetic analysis of [14C] sucrose uptake by isolated vacuoles revealed the presence of a saturable component with Km for sucrose uptake = 23 mM and Vmax = 21.2 nmol sucrose 10-6 vacuoles min-1. The saturable component was inhibited by SH-blocker, p-chloromercuribenzenesulfonic acid (PCMBS) and was substrate specific. The transport of sucrose was not changed by ATP with or without Mg2+, by the ionophore, valinomycin and by protonophores, carbonylcyanide m-chlorophenyl hydrazone (CCCP) or dinitrophenol (DNP). Sulfite at concentrations of 0.01-2.5 mM inhibited the uptake of [14C] sucrose by isolated vacuoles. Inhibition was of the noncompetitive type with K; = 2.48 mM of sulfite (22oC).
The effect of exogenous rhizobial lipopolysaccharide on symbiosis of Rhizobium leguminosarum bv. trifolii with red clover
Authors: Głowacka Maria , Stępień Agnieszka , Szyprowska Sylwia
Published: April 2013

The effectivity of symbiosis of Rhizobium leguminosarum bv. trifolii with red clover in the presence of exogenous lipopolysaccharide (LPS) preparation was measured as a yield of green mass of infected plants. The addition of complete LPS that had been obtained from homological Rhizobium strains influenced significantly the growth of plants. In the presence of defective LPS of Rhizobium mutant the effectivity of symbiosis did not change.
Diploidization of cucumber (Cucumis sativus L.) haploids by colchicine treatment
Authors: Nikolova Vesselina , Niemirowicz-Szczytt Katarzyna
Published: April 2013

Haploid cucumber plants are totally infertile and do not undergo spontaneous diploidization. The use of haploids depends on the possibility of doubling the chromosome number and the obtaining of stable doubled haploids (DH). Four haploids of different genotypes propagated vegetatively were treated with colchicine in order to obtain DH. The following procedures were used: 1) apical shoot meristem treatment, 2) soaking of shoot explants, 3) placing of shoot explants on medium with colchicine. Plants of the C1 generation were evaluated in respect to morphological and cytological characters and fertility. The best result of 20.9% DH was obtained after repeated treatment of the meristem with colchicine. A large group of chimeras (28.5%) was also distinguished as were haploids and tetraploids. DH plants were fertile and gave uniform progeny. Chimeras had a decreased fertility and showed disturbances in meiotic divisions.
The high frequency of variegated forms after in vitro mutagenesis in Saintpaulia ionantha Wendl.
Authors: Gaj Marek , Gaj Małgorzata D.
Published: April 2013

The leaf-explants of Saintpaulia ionantha Wendl. var.'miniature' were treated by different doses of MNH and cultured on shoot regeneration medium. A strong toxic effect of some MNH doses on explant survival during the first two subcultures was noticed. The explants surviving treatment regenerated shoots with the efficiency comparable to the control. The high number of shoots regenerated from mutagenised leaves showed chlorophyll chimerism (so-called variegated forms). The use of 5 mM MNH for 1.5 or 2 h was found very effective, as 100% of survived explants regenerated variegated shoots. Besides hundreds of variegated forms also leaf-shape and flower-colour variants were observed in MNH-treated culture. Somaclonal variation was not observed in the control culture. The results indicate the great efficiency of in vitro applied MNH for in-duction of morphological variants of Saintpaulia, and especially variegated forms.
Estimation of aluminium pollution in oak stands on the Krotoszyn Plateau
Authors: Opydo Jadwiga
Published: April 2013

Estimation of the degree of aluminium absorption by oak stands on the Krotoszyn Plateau and on reference areas is reported in this paper. Soil pH, the content of exchangeable aluminium in soil and the content of aluminium in the xylem and roots of Quercus robur L. were determined. The performed studies show a very strong acidification of soils from the investigated areas of the Krotoszyn Plateau; pH vs. 1 M KCI did not exceed 4.0, whereas the content of exchangeable Al in some places was 50 mg/100 g. The results also showed an elevated content of aluminium in the wood and roots of oaks growing on the Krotoszyn Plateau as compared to oaks in Zawiercie (near a Steel Mill), where the reaction of soil is neutral. The content of Al in the xylem of oaks from the Krotoszyn Plateau was over the range 3.8-9.9 µg/g, in the roots 198-499 µg/g, that in the xylem and roots of oaks in Zawiercie was 1.5 µg/g and 56 µg/g, respectively
PCC-like induction of mitosis in Chara vulgaris antheridia initiating differentiation of spermatozoids in the darkness
Authors: Kwiatkowska Maria
Published: April 2013

The objects of this research were the antheridial filament cells of Chara vulgaris which after 5-day mitodepressing treatment of the darkness reactivated mitosis (without light stimulation) in the result of the physiological state evocing the initiation of spermiogenesis in the antheridium. The course of these divisions was observed in relation to control cells cultivated in the natural photoperiod L:D = 14:10. It was shown that the passage of dark-arrested cells from early G2 (VII stage) to the early prophase in the cells linked to the base of filaments by plasmodesmata with spermatids initiating spermiogenesis, resembles the prematuraly condensed chromosomes (PCC). In this way a by-pass of the cells in the stage VII to early prophase occurs without reconstruction of granular components of nucleoli and with condensed stage of mitochondria characterising the dark-arrested cells. In opposition to this phenomenon in the control cell cycle and in light-induced reactivation of mitosis in the dark-arrested cells, initiation of the prophase follows the series of changes of the nuclear ultrastructure (VIII stage - decondensation of chromatin, IX and X stages nuclei with reticulate chromatin). At the early prophase, irrespective of the physiological conditions, the electron-transparent space appears between nuclear envelope and the chromatin as the effect of solublisation of lamins. The fine fibrils pass this space and link chromatin to the inner nuclear membrane.
Stimulatory effect of auxins and cytokinins on carotenes, with differential effects on xanthophylls in the green alga Chlorella pyrenoidosa Chick.
Authors: Czerpak Romuald , Bajguz Andrzej
Published: April 2013

Research concerning the influence of auxins and cytokinins on the content of carotenoids in Chlorella pyrenoidosa (Chlorophyceae) has been conducted. The strongest stimulating effect on carotenoids content in Ch. pyrenoidosa biomass was exerted by cytokinins (N-6-benzylaminopurine and N-6-furfurylaminopurine) and allantoin, weaker by auxins and their chemical analogues, and the weakest by tryptamine and 2,4-dichlorophenoxyacetic acid compared to the control. Under the influence of cytokinins the content of α- and β-carotene have been stimulated several times stronger than by auxins, and especially 2,4- dichlorophenoxyacetic acid and tryptamine. However, oxygen-rich xanthophylls content was most strongly reduced by cytokinins (60-70% in relation to the control) in the 20 day lasting of Ch. pyrenoidosa cultivation, similarly to auxins: 1-naphthaleneacetic acid, indole-3-butyric acid, 2,4- dichlorophenoxyacetic acid.
The effect of exogenous acetylcholine and other cholinergic agents on photoperiodic flower induction of Pharbitis nil
Authors: Łukasiewicz-Rutkowska Hanna , Tretyn Andrzej , Cymerski Mariusz , Kopcewicz Jan
Published: April 2013

Exogenous acetylcholine (ACh), acetylcholinesterase (AChE) inhibitors, as well as agonists and antagonists of ACh receptors applied on the cotyledons of 5-day-old seedlings of Pharbitis nil during a 16-hour long inductive night or during a 12-hour long subinductive night, do not essentially influence the flower bud formation. Also the application of above mentioned substances to the seedlings growing under the conditions of 72 hours of darkness, 24 hours of light and then 24 hours of darkness does not influence in an essential way flowering of P. nil. On the other hand, applying these substances on the cotyledons of P. nil during 24-hour-long inductive night, preceded by 72 hours of darkness and then 24 hours of light of lowered intensity finished by 15-minute-long impulse of far red light which inhibit flowering, caused the reversion of the effect of far red light irradiation and stimulated the flowering. The obtained results suggest that endogenous system ACh/AChE could participate in the mechanism of a phytochrome controlled flowering of short day plants.
The influence of soil water potential on the growth and survival of alfalfa rhizobia in the soil
Authors: Athar Mohammad , Johnson Douglas A.
Published: April 2013

Growth and survival of alfalfa rhizobia (Rhizobium meliloti Dang.) from Pakistan and Nepal were studied in vials filled with sterile soil maintained at -0.03, -1.0, and -1.5 MPa. The main effects of water level, rhizobial strains and length of exposure to desiccation and their interactions showed a highly significant (P S 0.001) effect on the number of rhizobia g-1 of soil. Growth and survival of rhizobia were highest in soil at -0.03 MPa followed by soil at -1.0 and -1.5 MPa. Highest cell counts were observed for strain UL 136 followed by strain UL 222 and the lowest was for strain UL 61. Two rhizobial strains (UL 136 and UL 222) were most tolerant to desiccation and showed highest growth and survival under low water potential. These two strains probably could be used as inoculants for alfalfa production under arid and semiarid environments.
Variability of Pinus mugo Turra clones from Ostry Wierch peat bog
Authors: Bączkiewicz Alina , Prus-Głowacki Wiesław
Published: April 2013

Present study aimed at determining genetic structure of the Pinus mugo Turra population, growing at a peat bog, on Ostry Wierch slopes in the High Tatra mountains, in respect to the number of genotypes present in the population, and at defining variabilities of morphological and anatomical traits. In the examined plants, isoenzymatic analysis demonstrated existence of only two genotypes (A and B), which formed relatively vast clones. Mathematical-statistical analysis of 13 anatomical - morphological traits of the needles proved that the examined clump consisted of two clearly distinguishable groups, corresponding to the two earlier electrophoretically identified clones A and B. The obtained data allowed to conclude that the method based on anatomical-morphological measurements may, at least in some cases, permit identification of Pinus mugo clones
Declines in populations of Salix caprea L.during forest regeneration after strong herbivore pressure
Authors: Faliński Janusz B.
Published: April 2013

Communities of broadleaved forest subject to strong pressure from large herbivores underwent degeneration. The relief of this pressure led to regeneration of the community, in which an important role was played by the sallow Salix caprea and other light-seeded pioneer species of tree (Populus tremula, Betula pendula and B. pubescens). Regeneration involving Salix caprea proceeded following the conservatorial protection of the degenerate stands in a reserve and later in Białowieża National Park. The emergence and development of the population of Salix caprea proceeded following the invasion of spruce, which coincided with the period of enhanced animal pressure on broadleaved forest. Salix caprea filled all the gaps in the tree stand arising as a result of the destruction of trees and undergrowth by herbivores (in the years 1892-1915). It also appeared en masse on old, at that time unforested, clearings and felled areas. In these places, Salix caprea created very abundant populations, with particular trees being in good condition, with a habit typical of forest trees and attaining considerable heights. The majority of trees were 50-60 years old at the time of death, although individuals reached 74 years of age. The process of extinction of the sallow population - observed over 19 years on permanent plots and fixed trees - proceeded very quickly, especially in the first decade of observation. It led to the almost complete disappearance of sallow for the forest communities of Białowieża National Park. The death of individual trees is preceded by impairment of their health and reduced annual increments in the 4-9 last years of life. The extinction of the population is associated with the loss of its primary phenological differentiation and with a change in the sex structure of the population from a prevalence of female trees to a near even distribution of the two sexes. The development of the populations of permanent constituents of the forest (Carpinus betulus, Tilia cordata, Acer platanoides and Ulmus glabra) under the canopy of light-seeded trees, and the non-creation of a new generation of pioneer species points to the imminent end of the process of regeneration in the forest communities of Białowieża National Park.
Cadmium-induced oxidative stress in potato tuber
Authors: Stroiński Andrzej , Kozłowska Monika
Published: April 2013

Short-term treatment of tuber discs of potato (Solanum tuberosum L.) with cadmium chloride elevated the concentration of active oxygen species (.O-2, H202) and activated the antioxidative system. Two cultivars, Bintje and Bzura, susceptible and tolerant, respectively, to cadmium were examined. In more tolerant, control tissues the activity of ascorbic acid peroxidase (AAP) and catalase (CAT) was higher than in the sensitive ones. During first hours of stress, the inhibition of superoxide dismutase (SOD), CAT and AAP was observed and it comes from inactivation of enzymes by cadmium ions. A subsequent activity increase of the enzymes aroused earlier in tolerant tissues. It seems therefore, that tolerant tissues possess a more efficient antioxidative system.
Taxonomic aspects of the iridoid glucosides occurring in the genus Plantago L.
Authors: Andrzejewska-Golec Emilia
Published: April 2013

The results of studies of the iridoid glucosides distribution within the genus Plantago indicated the significance of catalpol, plantarenaloside and bartsioside for the taxonomy of this taxon.
Ultrastructural response of cabbage outer leaf mesophyll cells (Brassica oleracea L.) to excess of nickel
Authors: Molas Jolanta
Published: April 2013

Changes in the structure and in the ultrastructure of cabbage outer leaf mesophyll cells [Brassica oleracea L.] cv. Sława from Enkhouizen were examined by means of light and electron microscopy. The examined plants were grown on the basic Murashige and Skoog medium with addition of excesive concentrations of nickel (added as NiSO4 x 7H2O),i.e. Ni 5, Ni 10 and Ni 20 mg/dm3. In Ni 5 mg samples mainly adaptation changes to the conditions of stress were observed. These changes were manifested by the increase of cytoplasm content and by cytoplasm vacuolization, by the increase of nucleus and nucleous volume, nucleolus vacuolization, the increase of plasmalemma invaginations and of the amount of rough ER, by the central arrangement of smooth ER and of the thylakoids of chloroplasts; it was also shown by the growth of the number of mitochondria and of peroxisomes in the cell. In Ni 10 mg samples, apart from adaptation changes, such as the increase of the nucleus volume, increase of plasmalemma invaginations, cytoplasm and nucleolus vacuolization, degeneration changes were also observed. They concerned mainly the nucleus (the increasing amount of condensed chromatin), ER (swelling and fragmentation of rER and sER), mitochondrium (swelling and reduction of cristae), Golgi apparatus (disintegration and decay) and chloroplasts (changes of shape, swelling and reduction of thylakoids, disappearance of starch and presence of big plastoglobuli). In Ni 20 mg samples cell protoplasts were in different stages of degeneration and the cell organelles that were identifiable, were usually damaged.
Rosmanol controls explants browing of Hypericum canariensis L. during the in vitro estabilishment of shoots
Authors: Mederos Sebastiana , San Andrés Lucía , Luis Javier G.
Published: April 2013

An efficient method for eradication of browning exudate was developed for Hypericum canariensis. For this purpose the effect of natural products on browning exudates were investigated in four types of culture media: Murashige and Skoog (MS, 1962); Gamborg's (B5, 1979); Woody Plant Medium (WPM, Lloyd and McCown 1981) and modified Quoirin and Lepoivre (QL.4) (Mederos 1991, Mederos et al. 1995) basal macroelements; these basal macroelements were supplemented with the microelement formula described by Murashige and Skoog (MS, 1962). During the establishment of shoots organogenesis potential was achieved in the Murashige and Skoog (MS, 1962) and modified Quoirin and Lepoivre (QL. 4) (Mederos 1991, Mederos et al. 1995) media after browning exudates was eliminated by rosmanol treatments. Rosmanol is a powerful diterpenic antioxidant isolated from Salvia canariensis L., a medicinal species endemic to the Canary Islands.
Fruit and seed structural characteristics and seed dispersal in Mercurialis annua L. (Euphorbiaceae)
Authors: Lisci Marcello , Pacini Ettore
Published: April 2013

The fruit of Mercurialis annua L. is a two-seeded capsule with a caruncle, a small appendage which arises from the outer integument in the micropylar area. The inner integument has a thick layer of Malpighian-like cells, interrupted at the micropyle by a remnant of nucellus, the walls of which contain suberin. There is no cuticle covering the caruncle and its cells have lipids and protein bodies as reserves. Seed dispersal occurs by a combination of autochory followed by myrmecochory. The explosive ejection of seeds is caused by dehydration-induced torsion of the mechanical layer of the fruit walls. This phenomenon is due to the different orientation of the cells and a folding over of the mechanical layer in the chalazal area. The seeds were found to be thrown distances from 1 to 130 cm (mean 41.1 cm; modal peak 10-20 cm). Ballistic dispersal is influenced by the weight of the seed. The seeds were collected by ants in a mean time of 24.4 minutes the maximum and mean distances of dispersal being 14 and 3.4 m, respectively. Of the seeds removed, 95.2 % were recovered on excavation of the ant nest. The seeds in the nest were intact but without the caruncles. The mean distance of dispersal by diplochory was < 5 m. These features are discussed in relation to possible benefits to the plant species in terms of adaptive advantages of seeds.
A qualitative study of the nodulating ability of legumes of Pakistan
Authors: Athar Mohammad
Published: April 2013

Legume-Rhizobium symbiosis accumulates substantial amounts of mineralizable nitrogen which help in ecological rehabilitation of degraded soils and increase the soil fertility in agricultural ecosystem. Nodulation was studied in 72 legume species from various parts of Pakistan. All the species of Papilionoideae and Mimosoideae were nodulated whereas all the species examined in Caesalpinioideae were non-nodulated. Attempts to elicit nodulation in Caesalpinioid species by rhizobial inoculation were not successful and they were accepted as lacking nodulating ability. Nodulation is reported for the first time in 6 species within 3 genera of Mimosoideae and 9 species within 5 genera of Papilionoideae. Majority of the species were abundantly nodulated under natural soil conditions or when grown in uninoculated garden soil indicating distribution of wide range of naturalized rhizobia. The study shows that the wild legumes hold great promise for inclusion in revegetation of denuded and derelict ecosystems.
Morphogenesis of root nodules in white clover. III. The effect of mutation in nod IJ genes of the microsymbiont upon the DNA level in the host tissue
Authors: Łotocka Barbara , Golinowski Władysław
Published: April 2013

On the basis of cytophotometric measurements a slightly increased DNA level in the nuclei of curled root hairs containing infection threads was observed in white clover inoculated with wild and mutant strains of Rhizobium leguminosarum biovar. trifolii, as compared to normal root hairs of te same plants. Cells of the root nodule primordia in 72 h after the inoculation, as compared to the root primary cortex, demonstrated an increased level of the nuclear DNA. No differences were observed in the nuclear DNA contents in individual layers of the cortex of the 28 day-old nodules. Generally it was low, varying from 2c to 4c. The meristematic and bacteroidal tissues in the effective nodules were characterized by a higher DNA level, as compared to the respective zones in ineffective nodules induced with the strains ANU261 (nod I*) and ANU262 (nod J*). The DNA level in the effective bacteroidal tissue varied from 4c to 32c, while in the tissue containing the strain ANU26l only the 2c-8c nuclei could be found and in the tissue with the strain ANU262 - the 4c-16c nuclei.
Embryological studies of reciprocal crosses between Vicia faba and Vicia narbonensis
Authors: Zenkteler Maciej , Tegeder Mechtild , Schieder Otto
Published: April 2013

A study was undertaken to asses the reciprocal crossability between Vicia faba and Vicia narbonensis. Flower buds or only ovaries of several varietes and genotypes were cross-pollinated in vivo (green house and field) and in vitro. Only few pollen tubes passed the style and entered into the ovary. On the whole number of 5320 cross pollinated in vivo and in vitro flowers and ovaries of Vicia narbonensis only 78 globular hybrid embryos were observed. After cross pollination in vivo of 3860 flower buds and ovaries of Vicia faba globular embryos developed in 124 ovules. The highest number of globular embryos were obtained when the Vicia faba line 1/33 was pollinated with Vicia narbonensis lines P3, P5, 150, SE.Embryogenesis proceeded till the 6-10 day after pollination, however, karyological disturbances in the cells of embryos and endosperm were often noticed at earlier stages. In vitro pollen grains of Vicia faba germinated on stigmas and ovaries of Vicia narbonensis, a significant increase in the growth of pollen tubes was noticed after ovary pollination. The technique of in vitro pollination was not suitable for Vicia faba as the inoculated explants died shortly after transferring onto the medium. The results indicate that finding a more suitable genotype for crossing may give a chance to obtain higher number of embryos (example line 1/33) - thus sufficient number for culturing them on media.
Pollen germination in vitro of Mexican Crataegus spp.
Authors: Borys M. W. , Alatorre Ma F. Soria , Salazar A. B.
Published: April 2013

The germination of pollen in vitro of 42 selections of Crataegus belonging to the cultivated group (C. pubescens (H.B.K.) Steud. = C. mexicana Moc. et Sessé) and wild group (probably C. nelsoni Eggleston) was evaluated. The anthers size (length and width) of each selection was also determined. Both attributes were determined by using undehisced anthers of flowers of the spring flowering period (dry season). The percent of germinated pollen varied from 82.4 to 94.2%, depending upon the selection; both groups of selections gave similar values of germination. The 45.83% of selections of the wild group gave from 88 to 90% of germinated pollen. The selections of cultivated group have been characterized by a wide range of pollen germination. The anther size - length and width - depended upon the selection. The plants of the cultivated group showed a larger size more frequently than those of the wild group. No correlation was found between pollen germination and anthers dimensions. The results were discussed in relation to productivity of fruits trees of the Mexican representatives included in the germplasm collection.
ABA in photoperiodic induction of Pharbitis nil.
Authors: Kulikowska-Gulewska Halina , Galoch Elżbieta , Kopcewicz Jan
Published: April 2013

The endogenous content of ABA in the cotyledons of Pharbitis nil is high during the light phase before an inductive 16-h-long dark period. During the night, however, at the beginning, the level of ABA is relatively low with the tendency to increase during the second half of an inductive dark period. The dual effect of exogenous ABA on the Pharbitis nil flowering has been observed. ABA applied to the cotyledons on subthreshold photoperiod (12-h-long night) stimulates flower bud formation. On the other hand, however, ABA applied during an inductive (16-h-long) dark period, as well as applied to the medium of cultured plantlets, inhibits flowering. Thus, the flowering effect of ABA is clearly dependent on the state of flower induction which is different in plants growing on various photoperiods.
Isoenzymatic variability in some of the Polish populations of Norway spruce (Picea abies) in the IUFRO-1972 provenance trial
Authors: Modrzyński Jerzy , Prus-Głowacki Wiesław
Published: April 2013

The isoenzymatic studies performed on nine Picea abies H. Karst populations from Poland, indicated considerable genetic variation among investigated stands. Genetic similarities have demonstrated a clear pattern of geographic variability. Three of the nine studied populations (Zwierzyniec, Nowe Ramuki and Orawa) have shown markedly diverse characteristics compared to the remaining populations. The mountain populations have formed one group with two related subgroups. The mean number of alleles per locus (A / L = 2,22) and level of heterozygosity (Hp = 0,194) for the lowland populations are within the range of these parameters for other Norway spruce populations from Finland and Lithuania. The populations from Carpathians and Sudety mountains are geneticaly more polymorphic (Ho = 0,221, A / L = 2,34) than the others. This pattern of genetic variation suggests the existance of two gene pools, one from southern and one from northern Poland formed during the glacial period and differentiated further in southern Poland into two subpools.
Materials to North American lichen flora
Authors: Bystrek Jan , Fabiszewski Jerzy
Published: April 2013

In Jerzy Fabiszewski's collection of lichens from North America of 1969-1970 there are several species of the Usneaceae family. Fifteen species of Bryoria have been found, among others: Bnyoria fabiszewskiana Bystr. nova species, Br. fur-cellata subsp. hawksworthiana Bystr. & Fabiszewski, nova subsp., Br. trichodes subsp. brodoana Bystr. & Fabiszewski, nova subsp. Br. trichodes subsp. canadensis (Mot.) Bystr. & Fabiszewski, nova comb., Br. ambigua (Mot.) Bystr. & Fabiszewski, nova comb., Br. tenerrima (Mot.) Bystr. & Fabiszewski, nova comb.
Two algorithms of determining the middle point of the shoot apex by surrounding organ primordia positions and their usage for computer measurements of divergence angles
Authors: Matkowski Adam , Karwowski Radosław , Zagórska-Marek Beata
Published: April 2013

The measurements of the divergence angle between organ primordia in magnolia floral apices and vegetative apices (embryonic shoots) of coniferous trees were performed, using computer application Phyl for IRIX. It appears that the values of the angle are strongly affected by the position of the apex centre, which was calculated by the program on a base of input positions of surrounding primordia. Two algorithms were used to determine the centre position: in program version Phyl 1 it was calculated as the gravity centre whereas in Phyl 2 version as a geometrical midpoint. The both methods differ in resulting centre position. This is dependent on such apex features as: proportions between its size and the size of primordia (expression of phyllotaxis), the angular distances between succesive primordia (quality of phyllotaxis), radial distances between primordia of different age (profile of the apical dome), the number of recorded primordia. The accuracy and reliability of both algorithms for determination of the centre position and, consequently, the reliability of divergence measurements were verified by applying them to ideal, computer simulated spiral phyllotactic systems with divergence given arbitrarily by the user. The conclusions from the results of simulations are that there is a possibility of selecting more suitable algorithm for particular apex with regard to specific parameters of its phyllotactic system.
Tissue-specific DNA methylation in Haemanthus katharinae Bak. (Amaryllidaceae)
Authors: Sakowicz Tomasz , Olszewska Maria J. , Łuchniak Piotr , Kaźmierczak Joanna
Published: April 2013

The level of DNA methylation was compared in root meristem, adult leaf and endosperm of monocotyledonous species, Haemanthus katharinae, with the use of HPLC, restriction analysis, Southern blot hybridization and in situ nick-translation driven by restriction enzyme HhaI The highest level of 5-methylcytosine was observed in adult leaf whose nuclear chromatin is particularly condensed, and the lowest in endosperm. The level of DNA methylation of repetitive HaeIII 4006p sequence follows that of the total DNA.
The metabolism of ageing seeds: changes in the raffinose family oligosaccharides during storage of field bean (Vicia faba var. minor Harz) seeds
Authors: Zalewski Kazimierz , Lahuta Lesław B.
Published: April 2013

Seeds of field bean cv. Nadwiślański harvested in 1980, 1986 and 1992 were studied. Results of investigations showed that the four analysed sugars (saccharine, verbascose, raffinose and stachyose) made up from 60.1 mg of 1 g dry matter of seeds harvested in 1992 to 67 mg of seeds collected in 1986. After three years of storage in laboratory conditions we observed a decline of the amount of these oligosaccharides. The saccharose:raffinose family oligosaccharides ratio grows with the seed age.
Uptake and assimilation of ammonium ions by cucumber seedlings from solutions with different pH and addition of heavy metals
Authors: Burzyński Marek , Buczek Józef
Published: April 2013

Influence of Cu2+, Cd2+, Pb2+ and Fe2+ in various pH conditions (5.0, 6.0, 7.0) on the uptake and assimilation of NH4+ by cucumber seedlings was estimated. Every metal in different pH of uptake solution distinctly reduced ammonium absorption calculated from NH4+ depletion. Copper and ferric ions, but not cadmium or lead, astonishingly decreased the uptake of ammonium from solution at pH 5.0. Cu2+ was also very active at pH 6.0. The accumulation of ammonium in roots of metals-treated seedlings at the same time was high. The high level of ammonium in root cells despite of its low uptake probably resulted from disturbance in NH4+ assimilation. Both glutamine synthetase (GS) and NADH-glutamate dehydrogenase (NADH-GDH) - the major enzymes in ammonium assimilation, were inhibited after one hour of plant exposition to the metals. Similarly as in the case of ammonium uptake, the influence of pH was visible only in combination with copper and ferric ions. The strongest reduction of enzyme activities was observed for Cu2+ and Fe2+, in pH 5.0 and 6.0. The various metals absorption by roots from solutions with different pH was not dedected. The data show correlation between metal inhibition of GS and NADH-GDH activities and metal inhibition of ammonium absorption.
Cytopathological changes in Schefflera actinophylla Harms. naturally infected with impatiens necrotic spot virus (INSV)
Authors: Rudzińska-Langwald Anna , Kamińska Maria
Published: April 2013

Plants of Schefflera actinophylla Harms. with stunted growth, chlorotic and necrotic spots and patterns, leaf epinasty and distortion are infected with impatiens necrotic spot virus classified as a member of genus Tospovirus. Studies with electron microscope revealed that in cells of S. actinophylla leaves there were no virus particle inclusions typical for tospovirus infection, but only single particles were present. The isolate of INSV was defective and the amount of INSV particles was strongly reduced in Schefflera plants. Some inclusions (I type) were composed of short branched cisterns of endoplasmic reticulum and a dark substance forming characteristic bands. The II type represented inclusions that were usually ballshaped and composed of a dark substance resembling that of the I type, but not accompanied by endoplasmic reticulum cisterns. The III type of inclusions was composed of dark, osmophilic masses. The inclusions present in the cells differ from those typical for tospovirus infection.
Chara strigosa A. Braun (Characeae) in Poland
Authors: Hutorowicz Andrzej , Langangen Anders
Published: April 2013

Chara strigosa is reported from several lakes in Poland. The finds were published by Izabella Dąmbska in 1966, but have not been recognised internationally, presumably because Dąmbska's article was published in a local paper in Polish. We give a short description of Charetum strigosa first described by Dąmbska. One of the lakes with C. strigosa is reported with luxuriant growth of a blue-green bacteria common in water blooms. There is a need to survey these lakes in order to prevent an increasing eutrophication.
Long-term changes in size and composition of seed bank during succession: from meadow to forest
Authors: Falińska Krystyna
Published: April 2013

Studies of the relation between the size and floristic composition of the seed bank and the vegetation during succession were conducted in the years 1976-1996. The results of the research did not confirm the hypothesis of directional changes in the density of seeds as the observed changes were of fluctuating nature. At the start of succession the seed bank was small (2970 seeds/m2), and in subsequent years the density of seeds increased successively to reach the highest level after 15 years (9170/m2 ), then dropped again. After 20 years the density of seeds reached the value recorded at the initial stage (2468/m2). Successional changes in floristic richness of seed bank were directional with the number of species falling from 52 to 24. All data indicate that the floristic composition of the seed bank is not a mirror reflection of the vegetation structure, but rather a record of a long-term turnover of species and many different events which in various periods of time influenced the inflow of seeds to the soil (spatial dynamics of the necromass, perennial herb and willow canopy structure, seed migration).