Author Archives: Petri

Mycorrhizal fungi and biological activity of humus layer in polluted pine forests in the surroundings of Oulu

Authors: Markkola, Anna Mari & Ohtonen, Rauni
Journal: Karstenia, Volume 28 (1988), Issue 1, pages 45-47.
Doi: https://doi.org/10.29203/ka.1988.264
Full text: PDF

Abstract:  The condition and types of ectomycorrhizae of Scots pine Pinus sylvestris and the biological activity of soil micro-organisms in the humus layer of polluted pine forests were studied in the surroundings of Oulu, northern Finland. Biological activity, expressed as the rate of humus respiration and as dehydrogenase enzyme activity, decreased towards the central, most polluted area with higher sulphur and nitrogen contents in the humus layer. The ectomycorrhizae of Scots pine were less ramified and poorly developed in the central area. The number of mycorrhizal types and the number of mycorrhizal species encountered in the sporophore inventories were lower in the two most polluted zones than in the cleaner sites. The type composition of the mycorrhizae was altered in the polluted sites.

High aluminium tolerance among ectomycorrhizal fungi

Authors: Hintikka, Veikko
Journal: Karstenia, Volume 28 (1988), Issue 1, pages 41-44.
Doi: https://doi.org/10.29203/ka.1988.263
Full text: PDF

Abstract:  The aluminium tolerances of 12 ectomycorrhizal and 48 saprophytic fungi, mainly basidiomycetes were studied by cultivating aseptic cultures on MMN or ME solution to which aluminiun sulphate, potassium aluminium sulphate or aluminium chloride was added. Suillus luteus, S. variegatus, S. bovinus and Paxillus involutus grew in concentrations over 10 g Al+++/l. Species of Amanita and Trichloma were more sensitive. Saprophytic species (Mycena, Marasmius, Pleurotus) had in general much lower tolerance, concentrations of 100-250 mg Al+++/l being limiting. It is suggested that the high tolerance of mycorrhizal species can be regarded as an adaptation to naturally aluminiumrich conditions in acid forest soils.

Observations on Scots pine mycorrhizae in the surroundings of a fluting mill

Authors: Holopainen, Toini & Vaittinen, Saila
Journal: Karstenia, Volume 28 (1988), Issue 1, pages 35-39.
Doi: https://doi.org/10.29203/ka.1988.261
Full text: PDF

Abstract:  The distribution of Scots pine mycorrhizal types and the cytopathology of selected mycorrhizae were studied in the surroundings of a fluting mill in Central Finland. A decrease in the mycorrhizal types was observed in the close vicinity of the factory. The mycorrhizae showed several disturbances in their ultrastructure, the most important being accumulation of tannins in the root cortical cells, intracellular penetration by the ectomycorrhizal fungi and accumulation of electron-dense deposits m the fungal vacuoles. The trees with only slight crown injuries showed clear injuries in their rootlets and mycorrhizae. A rapid staining method, Ponceau S, was tested for stammg pme mycorrhizae and the results of some staining trials are reported.

Correlation between mycorrhizae and the growth of Pinus sylvestris in ploughed sites in northern Finland

Authors: Väre, Henry
Journal: Karstenia, Volume 28 (1988), Issue 1, pages 31-33.
Doi: https://doi.org/10.29203/ka.1988.259
Full text: PDF

Abstract:  Scots pine saplings were examined in some clear-cut sites in northern Finland. The length of the saplings, the number of annual needle crops and the mycorrhizal infection percentage were recorded in saplings grown in ploughed and unploughed sites in order to reveal 1) the effect of ploughing on mycorrhiza formation and 2) the effect of possible disturbances in mycorrhiza formation on the growth of saplings. The mycorrhizal infection percentage was significantly lower in the double humus layer at ploughed sites than in the undisturbed humus layer at unploughed sites. The mycorrhizal infection percentage showed a significant positive correlation with the length of the saplings and the number of annual needle crops. In injured saplings, in which the length and number of annual needle crops were lowest, mycorrhiza formation was also poorest.

Comparison of radial growth rate of mycorrhizal fungi isolated from 43 species of northern orchids

Authors: Lindén, Ben R.
Journal: Karstenia, Volume 28 (1988), Issue 1, pages 19-25.
Doi: https://doi.org/10.29203/ka.1988.256
Full text: PDF

Abstract:  The investigation is part of a study devoted to the propagation of Scandinavian orchids. Endophytes from the roots of 43 orchid populations and, for comparison, from Moneses uniflora and four saprophytic fungi were isolated and the growth rates measured. The rates recorded ranged from 1.1 to 9.6 mm per 24 hours. The growth-retarding effect of tannin was also investigated. The response varied from total inhibition to no retarding effect. It is suggested that the differences in growth rates and response to retardants, which both seem to be dependent on the host taxonomy and ecology, can be of use in identifying the mycorrhizal endophytes.
Instead of the conventional isolating methods involving prolonged disinfection, the orchid roots were merely washed in soapy water, subjected to a high-pressure water jet, cut into segments and plated on plain water-agar medium. Contaminant-free cultures were easily achieved in this manner. Water-agar was also used for maintenance of cultures and growth rate observations.

Endomycorrhizal fungus in chlorophyll-free and green forms of the terrestrial orchid Epipactis helleborina

Authors: Salmia, Aulikki
Journal: Karstenia, Volume 28 (1988), Issue 1, pages 1-18.
Doi: https://doi.org/10.29203/ka.1988.255
Full text: PDF

Abstract: A brown, slowly growing unidentified fungus was isolated from nine (chlorophyll-free, yellowish-green and green) individuals of Epipactis helleborine (L.) Cranz collected from Finland. The brown fungus appeared regularly from sterilized root segments, and four isolates were obtained from hyphal coils in cortical cells of both green and white individuals. The results indicate that the same endophyte inhabited white and green plants of E. helleborine, and that the brown fungus can be considered to be the endophyte of this species, though this has not yet been confirmed with symbiotic tests. The effect of different surface-sterilizing agents on the appearance of the brown fungus from root pieces was investigated. The most suitable sterilization chemical proved to be 0.1% mercuric chloride in 50% ethanol. The morphology and some characteristics of the fungus are described. The growth pattern and microscopic chracateristics of the brown endophyte differ from those of the well-known orchid fungi. No teleomorph could be obtained in culture.