Growth of mycorrhizal fungi in dixenic cultures with bacteria in media of different composition.

Studies were carried out on the effect of bacteria: Arthrobacter globiformis, Bacillus subtilis and Pseudomonas fluorescens on biomass production by three important ectomycorrhizal fungi: Laccaria laccata, Hebeloma crustuliniforme and Rhizopogon vinicolor in media of different composition. It was shown that bacteria stimulated, inhibited or did not affect significantly the biomass production by mycorrhizal fungi. 3-factor ANOVA have shown that although effect of bacteria was statistically significant (p < or = 0.

Effect of the culture medium and incubation time on auxins production by bacteria isolated from the roots of pine seedlings (Pinus silvestris l.).

Studies were performed on the effect of culture medium and incubation time on the production of auxins by bacteria. The bacteria studied produced more auxins in the mineral medium containing glucose and tryptophan than in that enriched with casamino acids and yeast extract. The amount of auxins elaborated depended both upon the strain and the age of the culture.

Production of auxins by bacteria isolated from the roots of pine seedlings (Pinus silvestris L.).

Qualitative and quantitative studies were carried out on the production of auxins by Coryneform bacteria, the only bacterial types isolated from roots of pine seedlings. Almost all isolates were capable of producing auxins in tryptophan containing media. In media without this amino acid only trace or no auxins were produced.

Production of gibberellin-like substances by bacteria and fungi isolated from the roots of pine seedlings (Pinus silvestris L.).

The production of gibberellin-like substances by bacteria and fungi was investigated. A considerable number of the microorganisms studied produced these substances (55 and 86% of bacterial and fungal isolates respectively). Most of the organisms tested synthesized biologically active substances located on the chromatograms with the solvent system benzene, acetic acid (10:3 v/v) at Rf 0.