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Ectomycorrhizae of an Alpine spruce forest
1995
Pillukat, A. (Munich Univ. (Germany). Inst. for Systematic Botany)
The ectomycorrhizal biodiversity of selected Norway spruce stands on an Alpine limestone mountain was studied by inventories of occurring fruitbodies and descriptions of new ectomycorrhizal types. Based on fruitbody surveys a total of 137 ectomycorrhizal and 48 saprophytic species was recorded. Dependent on elevations as well as microclimatic, soil, and stand conditions there were significant differences in the fungal composition and number of species between the investigated forest plots.
显示更多 [+] 显示较少 [-]Mineral nutrient acquisition in nonmycorrhizal and mycorrhizal plants
1995
Marschner, H. (Hohenheim Univ., Stuttgart (Germany). Plant Nutrition Inst.)
Root-induced changes in the rhizosphere and root colonization with mycorrhizal fungi have marked influence on mineral nutrient acquisition from soils. Enhanced exudation of organic acids under phosphorus deficiency is a widespread phenomena in woody species forming root clusters. Root colonization with endomycorrhizas (AM) and ectomycorrhizas (ECM) increases the spatial availability of nutrients in the soil and enhances plant growth particulary on nutrient-poor soils. Most of these studies have been conducted under controlled environmental conditions and with annual plant species mycorrhizal with AM. Conclusions on the role of ECM colonization for nutrient acquisition of trees in forest stands are not possible at the present state of knowledge.
显示更多 [+] 显示较少 [-]Norway spruce: cytogenetic studies using different dividing tissues and methods
1995
Guttenberger, H. | Kohler, B. | Muller, M. (Graz Univ. (Austria). Plant physiology Inst.) | Borzan, Z. (Zagreb Univ. (Croatia). Forestry Fac.)
The haploid chromosome set of Norway spruce consists of 12 chromosomes. Most of the chromosomes are very similar in their morphology (length, arm ratio, secondary constriction). For the CGBI it is necessery to recognize all chromosomes. Therefore we used different banding methods to solve this problem. We used the root meristem and the dividing cells of the macrogametophyte as test objects. We discussed morphology of chromosomes of these two different dividing tissues. The use of image analysis equipment made it possible to get in a relatively short time a great number of data for statistical analysis. Another method was, to use an expert-system for data analysis. Finally 3-D models of interphase nuclei were reconstructed.
显示更多 [+] 显示较少 [-]Epicuticular wax morphology in pollution research - a critical evaluation
1995
Bermadinger-Stabentheiner, E. | Grill, D. (Graz Univ. (Austria). Plant Physiology Inst.)
To use alterations to epicuticular wax morphology as a successful tool in forest damage research, however, it is necessary to distinguish environmental influence and artefacts from common pollution effects. This paper gives a short review about alterations to epicuticular wax morphology of spruce needles.
显示更多 [+] 显示较少 [-]Giemsa C-banding of the chromosomes in the macrogametophyte of norway spruce
1995
Kohler, B. | Guttenberger, H. (Graz Univ. (Austria). Plant Physiology Inst.) | Borzan, Z. (Zagreb Univ. (Croatia). Forestry Fac.)
Giemsa C-banding method was applied on chromosomes in the female gametophyte tissue of Norway spruce (Picea abies (L.) Karesten). A karyogram of one single tree growing in the Botanical Garden of the University of Graz, Austria, was made by using an image analysis system. All chromosomes (n=12) showed pericentic C-bands. Chromosomes II, V and IX possed intercalary C-bands located at secondary constrictions. Telomeric C-bands appeared in chromosomes II and III on both arms.
显示更多 [+] 显示较少 [-]Antioxidants as indicators of stress in Norway spruce needles
1995
Ribaric-Lasnik, C. (ERICO, Velenje (Slovenia)) | Batic, F. (Ljubljana Univ. (Slovenia). Biotechnical Fac., Agronomy Dept.) | Grill, D. (Graz Univ. (Austria). Plant Physiology Inst.)
Among a variety of stress indicators for early identification of Norway spruce (Picea abies (L.) Karsten) decline the sulphur content, photosynthetic pigment content, activity of the enzyme peroxidase, watersoluble thiols and ascorbic acid in 4 age classes of 5 spruce needles were analysed. The 10 sampling sites were selected according to the degree of forest decline, sea level, distances from the Thermal Power Plant Sostanj and air pollution.
显示更多 [+] 显示较少 [-]Cytokinin content and metabolism in Norway spruce as influenced by environmental stress
1995
Bettin, D. | Matzad, H. | Hahn, H. (Hamburg Univ. (Germany). Institut f. Angewandte Botanik) | Von-Schwartzenberg, K. (Institut National de la Recherche Agronomique, Versailles (France)) | Doumas, P. (Institut National de la Recherche Agronomique, Olivet (France))
It was our aim to investigate whether the cytokinin status of Norway spruce seedlings (Picea abies L. Karst.) was changed when the plants were grown under nutritive stress. Cytokinins in shoots and roots from spruce seedlings, grown in various hydrocultural media with complete (control) or poor nutrient supply (stress), were determined by an indirect competitive enzyme-liked immunosorbent assay. The shoots of spruce seedlings grown in a poor acidic culture medium, to which aluminium ions (AlCl3, 0.8 mM) were added, showed up to 5-fold higher concentrations of zeatin riboside and isopentenyladenosine (iPa). When adding naphtylacetic acid to the nutrient medium also higher levels of cytokinin ribosides were measured in the shoots. In the roots however cytokinin riboside levels did not increase significantly under Al- or auxin treatment. Feeding experiments using tritiated iPA have shown that the metabolism of this cytokinin is strongly retarded in the roots of stressed seedlings. The experiments show that acid conditions and nutrient shortage together with aluminium ions in the rhizosphere increase the number of lateral roots in Norway spruce seedlings. It is assumed that the increased number of sites of cytokinin biosynthesis and the reduced metabolism of iPA result in the higher content of cytokinin ribosides in the shoots of seedlings.
显示更多 [+] 显示较少 [-]The effect of pollution on the cytokinin content of Norway spruce needles
1995
Dent, R.M. | Hanke, D.E. (Cambridge Univ. (United Kingdom). Plant Sciences Dept.)
Work was carried out to investigate the effect of pollution on the needle cytokinin content of mature Picea abies (L.) Karst individuals. Needles were collected from trees growing at two sites, one polluted and relatively non-polluted, in central Slovenia. After ethanolic extraction and purification, the needle cytokinin extracts were separed by reverse-phase HPLC. Cytokinin content was analysed using four direct ELISA techniques specific for Z-, DHZ- and iP-type cytokinins and the O-glucoside conjugate of Z. Results showed a trend towards the accumulation of cytokinins in needles from trees subject to high levels of atmospheric pollution, particulary with respect to ribotide derivatives. No difference was found in the (OG)Z content between polluted and non-polluted samples. The results are discussed with respect to the origins of the observed accumulation.
显示更多 [+] 显示较少 [-]Mycobioindication of forest site pollution
1995
Kraigher, H. (Forestry Inst. of Slovenia, Ljubljana (Slovenia)) | Batic, F. (Ljubljana Univ. (Slovenia). Biotechnical Fac., Agronomy Dept.)
Types of ectomycorrhizae on Norway spruce were determined in soil cores from two differently polluted forest research plots from the emission zone of Sostanj Thermal Power Plant (TPP). The two plots are comparable regarding site characteristics, but are differently polluted by the emmissions from the TPP. During the vegetations season 1993, 21 soil cores were taken from each plot. In these all fine roots and ectomycorrhizal roots tips were counted and the percentages of different types were calculated. Additionally, soil mycorrhizae from underneath fungal fruit bodies were taken in order to characterize new types of ectomycorrhizae. Classical anatomical methods and molecular tools were applied for identification. 17 types of ectomycorrhizae were determined on 28443 root tips in soil cores from the heavily polluted plot (Zavodnje). The predominant types were Paxillus involutus, Xerocomus badius, Piceirhiza parallela and Piceirhiza inflata. On the less polluted plot (Mislinja) 24 different types were determined on 38502 root tips in equal volume and number of soils cores. The most frequent types were Hydnum rufescens, Amphinema byssoides, Piceirhiza oleiferans, Cenococcum geophilum and Lactarius lignyotus. Mycobioindication of forest site pollution through selective sensitive (here Hydnum rufescens), in comparison to unsensitive (here Paxillus involutus), fungal species in ectomycorrhizae is discussed.
显示更多 [+] 显示较少 [-]Cytokinins in Norway spruce seedlings as tester organisms of forest soil pollution
1995
Kraigher, H. (Forestry Inst. of Slovenia, Ljubljana (Slovenia)) | Hanke, D.E. (Cambridge Univ. (United Kingdom). Plant Sciences Dept.)
Cytokinins were analysed by a combined HPLC-ELISA method in needles of Norway spruce seedlings. The seedlings were grown in vitro on sterile or nonsterile soil substrates from two differently polluted forest research plots. Difference were predominantly found in the isopentenyladenine-type of cytokinins. These were elevated in seedlings, grown on polluted soils in comparison to those, grown on soils from the unpolluted plot. A possible explanation might be in the change of the metabolism in the roots due to pollution stress (when grown on sterilized substrates) or in change of the mycorrhizosphere organisms (when grown on nonsterile soil substrates). The model system using Norway spruce seedlings as tester organisms for soil pollution is discussed.
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