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Influence of different depositions of air pollution on fine roots and mycorrhizae of scots pine
1995
Munzenberger, B. | Lehfeldt, J. (Forest Ecology Inst., Eberswalde (Germany)) | Huttl, R.F. (Cottubs Brandenburg Technical Univ. (Germany). Chair of Soils Protection and Recultivation)
Distribution patterns of ectomycorrhizal types and length density of finest roots were investigated in three comparable Scots pine ecosystems located along a deposition gradient of air pollutants in the new states of Germany. The plots Rosa, located near Bitterfeld and Halle, had received high depositions loads of SO2, NOX and alkaline fly ashes due to chemical industries and brown coal fired power plants in the former German Democratic Republic. Taura, located near Leipzig, was moderately affected by air pollutants. The background site Neuglobsow is located in a remonte area north of Berlin. All the three plots were dominated by only a few mycorrhizal types. Mycorrhizal projection area of these types was highest in Neuglobsow and strongly reduced at the polluted plots. The distribution patterns of mycorrhizal types differed also qualitatively. Length density of finest roots was lower in the humus layer of Neuglobsow than in the humus layer of Rosa and Taura. The results are correlated to high nutrient inputs and high rates of N-mineralization at the impacted plots.
Afficher plus [+] Moins [-]The role of plant hormones as modifiers of sensitivity to air pollutants and other stresses
1995
Lucas, P.W. | Wolfended, J. (Lancaster Univ., (United Kingdom). Institute of Environmental and Biological Sciences)
Plant hormones play a major role in the development and control of a wide range of plant physiological processes. Here we examine the ways in which they may influence the response of plants to air pollutants both indirectly, for example through the control of stomatal behaviour by ABA and directly, through their reactions with oxidising pollutants, which can lead to the formation of further damaging molecular species.
Afficher plus [+] Moins [-]Some aspects of interpretation of forest trees defoliation data
1995
Bogataj, N. (Forestry Inst. of Slovenia, Ljubljana (Slovenia))
The evaluation of data on the forest tree condition is weak point in forest decline monitoring as it enables only a very rough estimation of the state of forest health. The paper analyses the interpretation of the forest tree defoliation data in order to estimate their relevance and applicability. Quality control results of defoliation assessment in Slovenia are presented and the state of defoliation with its changes in the year 1987, 1991, 1993, 1994 on the 16 km grid.
Afficher plus [+] Moins [-]The classification of chromosomal defects of spruce trees as an alternative in environmental studies
1995
Muller, M. | Grill, D. (Graz Univ. (Austria). Plant Physiology Inst.)
A plant test system by the classification of chromosome aberration in the root tip meristems of young spruce plants (Picea abies (L.) Karst.) has been used to study the environmental influence on the genetic material of trees at natural sites and under defined conditions of greenhouses and open-top chambers. All our results suggest that this plant test system is a valuable tool in environmental monitoring.
Afficher plus [+] Moins [-]Forestry and society-oriented research on the history of virgin forests and their future needs
1995
Mlinsek, D. (Ljubljana Univ. (Slovenia). Biotechnical Fac., Forestry Dept.)
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.
Afficher plus [+] Moins [-]The influence of altitude and exposition on the level of cytogenetic damage to Norway spruce in Slovenia
1995
Rogina, D. | Druskovic, B. (Biology Inst., Ljubljana (Slovenia))
Annual research has proven that the level of the so called natural cytogenetic damage to Norway spruce in Slovenia has been correctly estimated at 8. The results of cytogenetic bioindication calculated in accordance with this level show that average cytogenetic damage in the period from 1985 to 1992 enable us to determine environmental influences on the expression of cytogenetic damage.
Afficher plus [+] Moins [-]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.
Afficher plus [+] Moins [-]Fluorescence in situ hybridization - a tool for detecting interspecies hybrids in plants
1995
Sinkovic, T. | Batic, F. | Javornik, B. (Ljubljana Univ. (Slovenia). Biotechnical Fac., Agronomy Dept.)
Preliminary results and methodology related to the use of the fluorescence in situ hybridization technique for detection of plants hybrids are presented. Total genomic DNA probe preparation and the non-isotopic biotin probe labelling technique is presented. The use of an excess of unlabelled competitor DNA from a related plant species gives more constant results in determining whole plant genomes with in situ experiments on plant hybrids. Preliminary results of flourescence in situ hybridization for detecting alien rye chromatin and localisation on metaphase chromosomes and interphase nuclei in the bread wheat cultivar Yugoslavia are described. The methodology for detection of interspecies hybrids of common and sessile oak with flourescence in situ hybridization is given. The advantege of the use of total genomic biotin labelled probes for in situ hybridization is that it requires less effort than preparing species specific probes and the ease of interpretation of the results. The technique of fluorescence in situ hybridization is less species than other cytological techniques for higher plants and almost the same methodology can be used for detection of oak hybrids. The extraction of a high quantity of species specific DNA of high quality and probe preparation and labelling are the most important step.
Afficher plus [+] Moins [-]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.
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