Biologia, Bratislava, 54(1), 1999
This study analyses diatom diversity and relative abundance in Pulmarí lake (39° 07' S; 71° 05' W), in the Patagonian Andes Neuquén (Argentina). 147 diatom taxa were identified, 24 infrageneric taxa are new records for Argentina and a new variaty Navicula willeri Krasske var. Triundulata is described.
Key words: fresh water, benthic diatoms, Pulmarí lake, Argentina
Characiochloris apiculata Korshikov, an epiphytic green alga described from the norther Russia, was recognised in the Doevnice river, a left tributary of the Morava river (South Moravia, Czech Republic) following strong summer floods. The species grew well for several months in laboratory subcultures of the host alga, Oedogonium sp. Its cell cycle starts with a very short monadoid stage (several tens of seconds) with a rather poorly developed chloroplast, a minute, hardly perceivable stigma and a few contractile vacuoles, which soon stop functioning in the substrate-attached cells. Neither in the monadoid stage nor in the early phases of the sessile stage the presence of a cell wall could be confirmed. Observations of the life cycle seem to support the intermediate position of C. apiculata between Characiochloris and Characium, as proposed by Fott (1972).
Key word: Chlamydophyceae, Characiochloris apiculata, life cycle, cell wall, ecology, Southern Moravia.
Monthly changes in biomass (chlorophyll a) of stream periphyton were studied in relation to physico-chemical characteristics of water for a period of two years. Streams were mildly acidic (pH
< 7.2) and deficient in phosphorus (TP 1-80 mgL-1). Nutrient concentration generally increased during the periods of high flow rate. Periphytic biomass was generally low (1 to 39.6 mg chlorphyll a m-2) with the maxima observed during winter. Filamentous forms contributed to periphytic biomass maxima during winter. Scouring hampered algal accrual during the rainy season due to high flow rate. Periphytic biomass showed significant negative relationship with water current and concentration of phosphate. Water current was the most important determinant for temporal changes in periphytic biomass.Key words: stream, periphyton, biomass, chlorophyll a, seasonality, water currents, nutrients, India.
A collection of Sclerotinia sclerotiorum (Lib.) de Bary isolates obtained from sunflower, oilseed rape and poppy was characterised by morphological and biochemical characteristics in vitro and by the pathogenicity on different host-plants. The variability was found in the growth rate of isolates, sclerotia and oxalic acid production in vitro, and in the aggressivity to sunflower and winter oilseed raoe plants in vivo. A strong effect of temperature on the radial growth rate and sclerotia formation was observed. On the basis of isolate similarity some particular areas of sunflower cultivation in Slovakia were defined: the district Dunajská Streda, the area of Bratislava, Nitra, Nové Zámky and Levice, the southern part of central Slovakia, the district Trebišov and the district Michalovce.
Key words: Sclerotinia screlotiorum, variability, oxalic acid, aggressivity, sunflower, oilseed rape.
The lichens Anaptychia kaspica Gyeln. (new for Greece) and Collema subflaccidum Degel (new for Romania) are presented. Their distribution is shortly discussed. The validation of combination for Anaptychia crinalis (Schleich. Ex Schaer.) Vězda ex Nowak is discussed.
Key words: Lichens, Anaptychia, Collema, Romania, Greece.
Authors provide the description of Poa sejuncta Bernáthová, Májovský et Obuch and P. babiogorensis Bernáthová, Májovský et Obuch, two new and apparently endemic species from the Západné Tatry Mts and Mt. Babia Góra, respectively. The most reliable morphological characters for discrimination between Western Carpathian members of the P. glauca group (i.e., between P. margilicola, P. sejuncta and P. babiogorensis) may include particularly the length of ligule of the uppermost leaf, length and width of the uppermost cauline leaf-blade and hair-covering of both rachilla and palea. Differences in bedrock properties of habitats are also remarkable.
Key words: Poa sejuncta sp. nova, P. babiogorensis sp. nova, taxonomy, description, Western Carpathians, Slovakia, Poland.
Commented information about the chromosome numbers of twenty-six taxa of the flora of Slovakia is presented. Fourteen of them (Arenaria patula, Dianthus x helwigii, Elaeagnus angustifolia, Galium boreale agg., Morus rubra, Onosma visianii, Poa bulbosa subsp. vivipara, Plantago stepposa, Polygala major, Sempervivum marmoreum agg., Senecio doria, Silene vulgaris subsp. antelopum, Stratiotes aloides, Xanthoxalis corniculata) were analysed for the first time from the territory of Slovakia and the analyses of twelve of them (Arenaria serpyllifolia, Commelina communis, Echium maculatum, Lactuca viminea, Molinia litoralis, Persicaria maculosa, Sempervivum montanum subsp. heterophyllum, Senecio paludosus var. tomentosus, Senecio jacobaea, Scilla buekkensis, Scilla kladnii, Thlaspi improperum) are repeated ones. Some results should have taxonomical consequences.
Key words: chromosome numbers, vascular plants, Carpathians, Slovakia.
This paper describes and clarifies some of the trends in mass allocation in Dactylorhiza fuchsii to particular parts of the plant, especially to reproductive organs, under- and above-ground structures, and vegetative parts. Dactylorhiza majalis invests more biomass into above-ground shoot and generative organs than D. fuchsii. The reproductive strategy of these two orchids mainly depends on the quality of generative parts such as faded flowers, capsules or seeds.
Key words: Dactylorhiza fuchsii, Dactylorhiza majalis, energy, growth analysis, orchids, population ecology.
The aim of this project is to reconsider some of the characteristics of the critically endangered taxon Ledum palustre from the viewpoint of population biology such as population density, spatial structure, size structure, reproduction biology and healthy condition. Data about ledum palustre population were collected in July 1992 and 1993, and in Sep. 1994 in Klin peat bog. The results pointed to aggregatis arrangement, a higher number of flowering shoots in 1993 than in 1992 and deterioration of healthy condition from 1992 to 1993 of selected shrubs.
Key words: Ledum palustre, population density, spatial structure, size structure, reproduction biology, healthy condition, NW Slovakia.
Two distinct species-rich dry grasslands differing in a number of synmorphological and syndynamical characters were studied for variance in species richness (VSR) and for guild proportionality (VGP). WGP was approached through the concept of deviation of variance of species richness within guilds as departure from a null model. There was an excess of VSR at the majority of scales in both communities. In the Poo-Festucetum this excess is indicative of considerable heterogenity of the studied stand. Both excess amnd deficit of VGP that predicted by a null model were found in the studied grasslands. The guilds showing higher VGP than predicted by null model are represented by yhe three major dominant taxa (Sesleria albicans, Genista pilosa, Hypnum cupressiforme var. Lacunosum) in the Carici-Seslerietum. The clonal plants such as Festuca pallens. Thymus preacox, Hieracium bauhinii, Tortella inclinata and other showing high VGP form the matrix phase of the Poo-Festucetum. Tha gap explorators including spring ephemerals and a non-clonal perennials are representative guilds showing lower VGP than predicted by a null model. We hypothesise that vegetation patchiness caused by environmental heterogeneity and spatially limited dispersal of the non-clonal species appear to be a more plausible explanation for the patterns of VSR and VGP rather than the competitive exclusion would be.
Key words: Festuca pallens, Sesleria albicans, assembly rules, null model, species diversity, Tematín, Slovakia.
The present study deals with foliar features in a forest protected from disturbance for over 50 years. Adaptation of two wide-ranging forest species, Olea capensis subsp. capensis and Cassine perague by foliar anatomy and morphology was investigated between the forest and fynbos and the riverine and nonriverine habitats. The present investigation addresses leaf anatomical and, to a lesser extent, morphological data of these species. Qualitative as well as quantitative data pertinent to leaf adaptation are examined; qualitative data referring to such features as the compactness of the mesophyll, presence and density of trichomes, and the degree of sclerophylly. Qualitatively, leaf characteristics did not differ much between the environments nor did they vary substantially between stream and non-stream habitats for Olea capensis subsp. capensis. In the fynbos the mesophyll was more compact, the vascular bundles heavily sclerified and the palisade more strongly developed in the case of Cassine peragua. Quantitative data include thickness of the cuticle, epidermal cell size and stomatal frequency and length. Quantitatively O. capensis subs. capensis exhibited significantly thicker cuticle in the fynbos environment, on the other hand, than in the interior or margine of the fores, on the other. Furthermore, the stomatal frequency of O. capensis subsp. capensis was 34% higher in the fynbos than in the interior or margin of the forest. Also data showed that O. capensis subsp. capensis had a significantly thicker cuticle both adaxially and abaxially in the fynbos zone than in the interior or margin of the forest.
Key words: leaf anatomy, Olea capensis subsp. capensis, Cassine peragua.
The Karwinskia parvifolia (Rhamnaceae) flower develops in inflorescences arranged in axillary cymes of 2-5 flowers, having glabrous pedicels with small brownish spots, 5 triangular fleshy sepals, 5 white persistent petals, each petal grows over one stamen. Stamens are localised in the corners of green nectariferous intrastaminal disc. The pistil is grown together from two carpels and consists of two locules, each containing two ovules. The ovule is anatropous, bitegmic, crassinucellate, the mature embryo sac contains one egg-cell, two synergids, central nucleus and higher number of antipodal cells. Solid style has two bands of transmitting tissues. Papillose stigna consists of two lobes. Tapetum is of the secretory type. Pollen grains ara tricolpate and operculate with Zwischenkorper and thickened intive underlying the apertures. The structure of ektexine is granular, which differs from the columellate/tectate type of structure typical of most angiosperm pollen. The ektexine overlies a homeogenous-to lamellar endexine, which in turn surrounds a thick intine. There are numerous internal secretory structures in the pedicels, sepals and pistil, e.g. mucilage ducts and cavities, tannins containing cells, and ducts and cavities producing toxin mixture.
Key words: Karwinskia parvifolia, Rhamnaceae, flower, anatomy, Mexico.
Pollen embryos were obtained from genotypes Jaspis, HE 5237, Dissa and Shooner in anther culture experiments with spring barley (Hordeum vulgare L.) genotype. Formation of proembryos inside the cultured anthers during the first 10-14 days was significantly influenced by genotypes and type of culture media. In our experiment we used the following induction culture media: MS, N6 and NN with addition of 1.1 mM glutamine and 1.1 mM myo-inositol and all the media were supplemented with 7.9 µM 2,4-D, 1.2 µM kinetin, 1.2 µM BAP, 175 mM maltose and 175 mM sucrose. Pollen embryos developed and regenerated into plants. The best medium for green plants production was MS medium supplemented with 2.4 µM kinetin, 4.4 µM BAP, 2.7 µM NAA and 87.7 mM suchrose. Among the total 246 plants only 14 were green.
Key words: Hordeum vulgare L., anther cultures, haploids, green plants regeneration.
Comparative study on fertilization in self- and cross-pollinated ovules of silver fir (Abies alba Mill.) revealed the normal pattern of development in both polination types until mature archegonia. Disintegration of these structures observed in aborting ovules from selfing has been paralleled by persistance of dormant pollen grains at the top of nucellus. This figure has as a rule contrasted with the germinating pollen and subsequent embry formation in cross-pollinated ovules. The conclusion has been drown that excecpt for the generally postulated embryo inviability, self-incompatibilty may also occur as a barrier preventing self-fertilization of the species.
Key words: Abies alba, self-pollination, self-incompatibility, pollen, archegonium.
Diffusion and distribution of protein bodies (PB) extract from Pinus nigra seeds in agar medium plates were studied. After application of PB extract on filter paper discs it was placed on agar plates for 20 days. proteins diffused from the discs were distributed in the plates. Identical protein pattern (8-54 kDa molecules) of PB extract was defined by SDS-PAGE analysis in agar strips at different distances from the discs. The predominant peptides and proteins were 8, 9, 13 and 18 kDa. The 32-36 kDa proteins were absent. These results suggest that the proteins during the maintenance on agar medium plates were separated. Relative quantity of individual proteins was different in certain distances from the discs. It is probable thqat these proteins can be involved in defense of pine megagametophyte. We assume that proportion of individual proteins is also of importance in their defense function.
Key words: Pinus nigra, protein bodies extract, seeds, defense reaction, SDS-PAGE.
A study of black pine seed protein bodies with regard to the presence of defense-related proteins was performed. Interaction of the intact protein bodies with saccharides revealed specificity of surface membrane binding sites for chitin, cellulose, laminarin and the respective mono- or disaccharides. Crude protein function isolated from protein bodies possessed an ability to agglutinate fungal spores. Inhibition of the fungal spores agglutination confirmed the presence of lectine-like proteins specific to basic cell wall components.
Key words: conifer, Pinus nigra, protein bodies, lectin, spore agglutination.
Ochyraea tatrensis Váňa (Hypnobartlettiaceae) has been known up to this time from the Vajskovská dolina valley and the Krížska dolina valley, both in the Nízke Tatry Mts in Slovakia. In 1997 I found a new locality in the Nízke Tatry Mts in the Zadná voda valley. On all the localities Ochyraea tatrensis is very rare. It belongs among the most endangered mosses of the world. I propose to change the category of vulnerability from V to E in the Red Data Book of European Bryophytes.
Key words: Ochyraea tatrensis, bryophytes, mosses, distribution, endangered bryophytes, Slovakia.
Ultrastructure of root and leaf cells of the thermophilic species Zea mays L., and a herb tolerating freezing temperatures, Vallerianella locusta L., was investigated at various low temperatures and in maize plants also with respect to chilling tolerance. Electron micrographs are used to document cellular structure modifications conforming to physiological (metabolic, molecular) responses of plant cell to low temperatures reported in the literature. The review shows that non-freezing low temperatures as well as freezing temperatures following cold acclimation do not cause serious injury to the cellular structures. On the contrary, changes in nuclei, ER, ribosomes, Golgi apparatus , and plastids often indicate increased metabolic activities of the cell (synthesis of cold responsive proteins, synthesis and accumulation of sugars and other compounds involved in osmoregulation and cryoprotection, changes in lipid composition and degree of fatty acid unsaturation of cell membranes). The structural modifications do not seem to be specific for either early periods of chilling stress or cold acclimation. Similar changes in submicroscopic morphology were found in the cell of thermophilic species (Zea mays), herbs, which can tolerate freezing temperatures (Arabidopsis thaliana or Valerianella locusta), and several tissues of woody plants acclimated before the of freezing (Populus sp., Cornus sericea, Malus pumila).
Key words: ultrastructure, plant cells, stress responses, low temperature, cold acclimation.
The surface of the carapace of the planktic crustacean Daphnis magna sampled from a fertilized fishpond in W Slovakia was densely covered by a green alga. This green alga formed a simple prostrate 2-4-celled uniseriate or 5-8-celled biseriate single filaments as seen in the ulotrichacean genere Protoderma or Pseudendoclonium. Under laboratory conditions these short filaments radiating from a centre, and these finally giving rise to long ramified Stigeoclonium-like filaments. This paper describes and discusses the life cycle and main diagnostic features of the alga and its possible systematic position.
Key words: Chlorophyceae, Ulotrichales, epizootic algae, Protoderma daphnicola, Pseudendoclonium basiliense, Stigeoclonium cf. tenue, fishponds, Slovakia.
The Červené vrchy Mts and the Tichá dolina valley are relatively undisturbed territories of TANAP (the Tatry Mts National Park, Slovakia) in ecological terms with low visitor pressure. This is the reason why to carry out investigations and monitoring of bryoflora as well as chorology and biology of threatened taxa and spreading of apophytic and invasive species. The most valuable habitats are situated in alpine belt. Many rare, endangered and decreasing species of Slovak and European bryophytes are confined to them, e. g. Asterella lindenbergiana, Bucegia romanica, Mannia triandra, Scapania degenii, Tayloria lingulata, T. froelichiana. So far, 300 bryophytes have been registered in the studied area [94 species of liverworts (Marchantiopsida), 1 species of hornworts (Anthocerotopsida) and 205 mosses (Bryopsida)].
Key words: bryophytes, alpine habitats, red list, threatened bryophytes, apophytic species, Slovakia.
During 1994-1998 altogether 200 samples of Danube water were investigated and microscopic fungi were identified in all samples. Abundance and specific diversity of microscopic fungi can oscillate in surface water during seasons. This seasonal variability depends on availability and amount of substrate. In the Danube river fungi abundance ranged within 1 to 45 CFU mL-1 with maximum in summer sampling time. Five genera of the subdivisio Zygomycotina and 32 genera of the subdivisio Deuteromycotina were identified by routine isolation and cultivation methods with prolonged cultivation time to 7-30 days at room temperature and day light. The most frequently isolated species belong to the genera Penicilium, Acremonium, Alternaria, Cladosporium, Fusarium, Paecilomyces, Trychoderma and Mucor. In some cases the identified species belong to the genera Mortierella, Rhizopus, Candida, Aspergillus, Beauveria, Geotrichum, Gliocladium, Phialiphora, Stachyybotrys, Stemphyllium, Trychophyton, Verticillium and other. Rarely the species as Absidia, Zygorhyynchus, Arthrinium were isolated. Species diversity dynamics in longitudinal profiles in the Danube indicated more abundant diversity of the subdivisio Zygomycotina in profile Bratislava. Three species - Beauvaria bassiana (Bals.) Vuill., Verticillium lecani (Zimm.) Viégas were isolated in the Danube river water as new species identified in the Slovak Republic. The data reported here refer to importance of microscopic fungi monitoring in surface water. Knowledge about fungi occurrence in atypical environment contribute to extend information about the species diversity.
Key words: microscopic fungi, Deuteromycotina, Zygomycotina, surface water, Danube river, Slovakia.
The only representative of the genus Coronopus - an archeophyte C. squamatus (Forks.) Asch. Has been reported from Slovakia so far. Revision of herbarium material revealed another species - Coronopus dydimus (L.) Sm., an alien being new to the Slovak flora. The plant was collected in the Východoslovenská nížina lowlands, E Slovakia, in 1975.
Key words: Brassicaceae, Coronopus, Coronopus dydimus, alien species, Slovakia.
The names Allium ochroleucum Waaaldst. et Kitt. and A. ericetorum Thore are typified. The names A. ochroleucum subsp. pseudosuaveolens Zahariadi, A. zahariadii Májovský subsp. izahariadi and A. zahariadii subsp. michalkoi Májovský are invalid. The A. ericetorum group in the Westrn Carpathians can be preliminary grouped into grassland (A. ericetorum Thore) and saxicolous (A. ochroleucum Waldst. et Kit.) populations, the names should be used until the taxonomy of the A. ericetorum group is satisfactorily solved in the whole area of distribution.
Key words: Allium ochroleucum, A. ericetorum, taxonomy, nomenclature, Western Carphatians, Slovakia.
In the revision of the Senecio nemorensis group in the Carpathians five taxa, namely S. dacicus Hodálová & Marhold, S. germanicus Wallr. subsp. germanicus, S. hercynicus Herborg subsp. hercynicus. S. ovatus (P. Gaertn. et al.) Wild. subsp. ovatus and S. ucranicus Hodálová have been recognized. Full synonymy, descriptions, distribution data and ecological notes are presented.
Key words: Asteraceae, Compositae, Senecio nemorensis group, taxonomy, morphology.
During the investigation of riverine ecosystem of the Morava river (Slovakia) a temporal type of vegetation of emergent bank was found. The zonation depended on many ecological factors such as the dynamics of water level , time of exposure to the aerial conditions, desiccation, excessive illumination, and salinity. Five zones of vegetation were developed , strip of Eleocharis palustris forming the lower border of the bank, the strip of Carex brizoides building the upper limit of the emerging part. The abundance of C4 species, e.g. Eragrostis pilosa , Echinochloa crus-galli, Cyperus fuscus, and Portulaca oleracea in the middle zones of the transect was connected with the hot and dry summer. The vegetation of the emerged bank , such as this type, generally belongs to the endangered ones. Rare and endangerd species of flora of Slovakia e.g. Eragrostis pilosa, Dichostylis micheliana, Lythrum hyssopifolia, and Riccia cavernosa occurred there.
Key words: horizontal vegetation structure, environmental gradients, Morava river floodplain, Slovakia.
Evidence of increasing damage to coastal ecosystem and hardship for coastal populations are accumulating throughout the world. Millions of hectares of wetlands and inter-tidal flats have been destroyed or damaged globally as a result of uncontrolled development and land reclamation programmes. In India, about 4.1 million hectares are covered by wetlands of different categories; mangroves - occupy an area of about 6,740 square km which is about 7% of the world´s mangroves. The world´s total mangrove area which spreads over 30 countries, including India is about 99.300km2. Bhitarkanika mangrove forests of Orissa situated in the confluence of Brahmani and Baitarani rives, is an unique coastal ecosystem spread over 191.44 km2 having 62, out 64 species of mangroves found in India. Many chromium, manganese, iron and led mines located in the catchment of these rivers contribute greatly to the heavy metal load in the sediments of the mangrove ecosystems. The increasing toxicity of the heavy metals bringing about structural alterations and anomalies in meiotic and mitotic chromosomes of a number of tree mangroves are reported as compared to the plants grown in Hookitola island of Mahanadi delta devoid of heavy metal load. Significant decrease in the in situ DNA content in the roots as well as shoot meristematic cells of Aegiceras, Avicennia, Bruguiera, Cynometra, Excoecaria, Heritiera, Kandelia, Rhizophora, Xylocarpous were noted. The chromosomal aberrations like lagging, early separation, chromosome erosion and chromosome break were prominent in plants grown at the heavy metal contaminated sites. The overall decrease of mitotic index from 5.3% to 2.6%, genome length, volume and 4C nuclear DNA content suggest the mutagenic effects of heavy metals during DNA replication. Thus, the fragile gene pool of this ecosystem is threatened due to genetic erosion by heavy-metal stress.
Key words: chromosome aberrations, genome, heavy metal pollution, mangroves, nuclear DNA.
We investigated the response of dormant barnyard grass Echinochloa crus-galli (L.) P. B. seeds to various "germination pre-treatments" (GPT) which consisted in exposure of dormant seeds to conditions favourable for germination. Temperature during GPT (18, 25 or 36 °C) and length of GPT (1, 2, 4, 8, and 16 d) were varied. The dormand seeds which did not germinate during GPT were chilled at moist conditions and 5 °C (stratification), for up to 400 days. The rate of dormancy termination in seeds exposed to stratification was checked in samples removed from chilled material at regular intervals and left to germinate at 25 °C and 4L:20D photoperiod. The course of dormancy termination in seeds exposed to GPT was compared with control not exposed to GPT. Seed pre-treatment increased both the time required for dormancy termination by chilling and the percentage of seeds that did not germinate even after a long period of stratification. These seeds were not dead but conditionally dormant and germinated readily at 34 °C. The effect of GPT did not significantly increase with temperature of GPT period. Using temperature of 25 °C during GPT, the effect increased gradually with the length of GPT period and became fully manifested after > 4 d of GPT. Experiencing germination conditions by dormant seeds in the post-harvest period may influence pattern of germination in the field.
Key words: Barnyard grass, Echinochloa crus-galli, germination, seed, temperature, dormancy, stratification.
In both vegetative and generative organs of Karwinskia (Rhamnaceae), a genus of shrubs and trees from tropical and subtropical American regions, large amounts of secondary metabolites, one of which shows an antitumoural effect, are produced. Among many species, Karwinskia parvifolia Rose was found to be the best source of this antitumoural toxin peroxisomicine A1. Anatomical studies of K. parvifolia consider the differences in plant stem structurre is typical for dicotyledonous woody plants. In contrast to leaves, no differences in anatomical structure of stems grown under greenhouse and natural conditions were observed. The presence of secretory ducts shows no dependence on cultivation , the ducts are preserved in all observed stems of the species. The vegetative apex of K. parvifolia is of the Opuntia type, with well-differntiated cambium-like transitional zone. The large metaxylem vessels are irregularly dispersed, libriform with very thick cell walls is well pronounced. Circular vessels in outline are arranged in a diffuse-porous pattern. Tracheary elements have simple perforation plates in oblique walls and short tails on both ends. Inervessel pitting is bordered, alternate, pits are circular with lenticular-shaped apertures. Vessel-ray and vessel-parenchyma pits are similar to those of intervessel pits, libriform fibres and parenchyma rays have simple pits.
Key words: Karwinskia parvifolia, Rhamnaceae, stem, anatomy, xylem, vegetative apex.
A fumigated nursery bed on a sandy loam was inoculated with the ectomycorrhizal fungus Pisolithus tinctorius and seeded with Acacia nilotica. Two types of inoculum were compared: mycelium grown in a vermiculite/peat mixture and mycelium grown in liquid medium and entrapped in a calcium alginate gel with different quantities of mycelium. At the end of the first growing season the alginate inoculum at the dose of 4 g mycelium (dry weight) per m2 proved to the most efficient. The top dry weight of the seedlings in this treatment was 2.0 fold that of the non-inoculated fumigated control. This inoculation treatment also ensured 90 percent mycorrhizal infection by Pisolithus tinctorius.
Key words: Pisolithus tinctorius, inoculum, alginate, vermiculite, peat.
The qualitative properties of the anthodium of Anthemis tinctoria L. (Cota tinctoria) cultivated at three different localities of the Slovak Republic during the course of ontogenesis were studies. The localities differed in both climatic and soil conditions. Evident differences with respect to the content of flavonoids did not occur. The highest content of flavonoids in the individualparts of capitulum were found in the rays corolla in the third ontogenetic phase, which is regarded as the optimum one for the harvest.
Key words: Anthemis tinctoria, anthodium, flavonoids, pharmacological properties.
Three-day-old plants of two Al-tolerant (Bavaria, Garant) and two Al-sensitive (SK-4410, Alfor) barley cultivars were grown in 0.05 or 0.1 mM AlCl3 in 0.1 mM CaCl2 (pH 4.5). Both Al concentrations caused significant inhibition of the root growth of all cultivars. The percentage of growth increments in 0.05 and 0.1 mM AlCl3, respectively, decreased in the following manner: cv. Bavaria (38%, 18.1%) > cv. Alfor (17.8%, 8.4%) = cv. Garant (16.8%, 12.9%) > cv. SK-4410 (7.5%, 5.6%). Studies of the root tip surface revealed transversal cracks in peripheral tissues and root thickening. The detection of Al studied by hematoxylin and morin staining was positive in rhizodermal and hypodermal cells of the cracked region only. Rhizodermal cells and the 2nd to 3 rd outer cortical layers of the cracked region showed the presence of callose. In older root parts neither induced callose formation nor Al presence were detected. No correlation between Al-tolerance and callose synthesis was found.
Key words: aluminium, barley, callose, histochemistry, root growth.
Seminal roots of two maize (Zea mays L.) genotypes, chilling-tolerant Z7 and chilling-sensitive Penjanilan, have been used to study the effect of low growth temperature on respiration, especially on the CN-resistant, salicylhydroxaamic acid-sensitive alternative pathway of respiration. After pregrowth at 24 °C until the third-leaf stage, seedlings were subjected to moderate (14 °C) or severe (6 °C) chilling stress for 2 to six days. For the recovery experiments plants were transferred back to 24 °C for another 5 days. Moderate chilling growth temperature had almost no effect on root respiration rate and partitioning of electrons in chilling-tolerant Z7 plants. In chilling-sensitive Penjalinann the decrease of root respiration was observed. This decrease was directly related to decline in cytochrome pathway activity. Severe chilling temperature showed initially an increase in total respiration particularly in chilling-tolerant Z7. The alternative pathway capacity and cytochrome pathway activity increased concomitantly with the overall respiration. Prolongation of chilling to6 days resulted in an additional enhancement of alternative pathway capacity which was accompanied by some loss in cytochrome pathway activity in both genotypes being higher in chilling-tolerant Z7. After re-warming of plants, the values of total respiration rate and cytochrome pathway activity increased in both genotypes but over 5 days did not reached the levels found in roots grown still at 24 °C. The levels of alternative pathway remained the same or decreased only slightly. We conclude, that the increase in the capacity of alternative pathway in maize roots during the chilling is primarily the effect of low growth temperature. But the quantitative differences exist between the genotypes differing in tolerance to chilling.
Key words: alternative pathway, low, temperature, maize, respiration, roots.
Alterations of protein composition in Al-sensitive and resistant barley cultivars were examined in extracellular and intracellular compartments of the roots after Al stress. The greatest changes in protein composition were found in cell wall fraction of roots. Exposure of roots to 100 µM Al resulted in reduction of several proteins in both Al-sensitive and Al-resistant plants. However, at the same time the synthesis of six different proteins was stimulated. Two of them with molecular mass of 14 and 16 kDa accumulated only in the resistant cultivar, while the other four proteins were accumulated in both Al-sensitive and Al-resistant cultivars. Within the peripheral membrane proteins Al-induced reduction of small polypeptides was observed. In the fraction of integral membrane proteins, Al stress induced accumulation of four proteins, three of which were accumulated both in sensitive and resistant cultivars. Analysis of cytoplasmic proteins revealed a very intensive Al induced accumulation of 28 kDa polypeptides in roots of both Al-sensitive and Al-resistant cultivars. The observed differences in polypeptide pattern between control and Al-treated roots indicate the role of these proteins in the response of barley plants to aluminium stress.
Key words: aluminium, barley roots, cell wall proteins, peripheral and integral membrane proteins, cytoplasmic proteins.
Protein composition in Al-sensitive and Al-resistant barley cultivars were examined in several cell compartments of the first leaf after Al stress. No differences were found in protein profiles of cell wall and peripheral membrane fractions between control and Al treated plants of both barley cultivars growing in solution with 100 m mol L
-1 AlCl3. One cytoplasmic protein with molecular mass of 28 kD and one 29 kD integral membrane proteins were activated only in sensitive cultivars, while in resistant plants the protein profiles of barley leaves remained without changes. These results indicate that Al stress applied to the root of Al-sensitive barley cultivars might be spread to the upper part of a plant and, as a consequence of Al- or other kind of secondary stress protein composition in leaves can be influenced.Key words: Hordeum vulgare L., barley, leaf proteins, aluminium stress,
In this study the effect of Al on the electrical membrane potential (Em) of outer cortex root cells of three-day-old maize seedlings has been studied. The Em values of root cells ranged between –115 and –146 mV. Em of older cells towards the root base was considerably more negative than that of the young root tip cells. Experiments with NaCN + SHAM revealed that the diffusion potential (ED) of root tip cells is smaller than that of root base cells. In short term experiments Em has been rapidly and significantly depolarized by Al. The depolarization was concentration dependent and reached the maximum at 150 µM Al. The extent of membrane depolarization by 100 µM Al decreased continuously from the apex to the base of the root. Simultaneously, the number of cells without any response to Al considerably increased in the region from 10 to 35 mm behind the root apex. Interestingly, this apparent insensitivity correlated well with the differentiation of the known maize root exodermis. No Em changes have been observed in cells more distant than 40 mm from apex. The sensitivity of the cells to Al decreased in radial direction and when the tip of the microelectrode reached the interior of the central cylinder Al induced no Em changes. Both the P-ATPase activator fusicoccin and glucose diminished the depolarizing effect of Al on Em. Exposure of roots to Al treatment retarded K+ efflux from root tip segments and had no effect on K+ efflux from segments of the root base. The present results suggest that, in short-term experiments, Al does not directly affect the electrogenic membrane H+-ATPase.
Key words: aluminium, diffusion potential, electrical membrane potential, fusicoccin, maize root cells, pH changes, potassium efflux.
Four genotypes of plum (Prunus domestica L.) and myrobalan (Prunus cerasifera Ehrh.) naturally infected with plum pox virus (PPV) were analysed to investigate the possibility of seed transmission. All the trees were observed to develop typical symptoms of PPV infection on leaves. The fruit symptoms differed among genotypes. All the analysed trees were PPV-positive in DAS-ELISA and RT-PCR. RsaI-based restriction analysis of RF-PCR revealed the presence of PPV-M isolates (in cv. Bystrická and Vlaška) and PPV-D ones (in cv. Tuleu Gras and murobalan). Using DAS-ELISA, PPV could not be detected in any part of seed of all genotypes. Totally 104 seedlings from stratified seeds were periodically tested using DAS-ELISA for evaluating PPV infection during 2-year period. Not even in single case was PPV antigen detected. On the basis of the results it can be claimed that the identified PPV isolates are not seed-transmitted in Prunus genotypes tested.
Key words: plum pox virus, seed transmission, DAS-ELISA, RT-PCR, plum and myrobalan trees.