The paper presents results of investigations on the relations between the type of substrata and the development of mycorrhizae in Pinus sylvestris seedlings at forest nursery. It was proved that poor soils are more suitable for mycorrhizae development. The results show that pine seedlings growing in control possess the highest number of well-developed mycorrhizae, i. e., on average 68 mycorrhizae per one seedling (the control was equaled to 100 %). In litter from pine stands and in decomposed peat the numbers of mycorrhizae were similar 84.6 % and 84 %, respectively. When litter of oak stands was used, the total amount of mycorrhizae reached 91.3 %, and the ectomycorrhizae increased by 27.9 % comparing with ectendo- and dead mycorrhizae. Various morphotypes of ectomycorrhizae were most spread in seedlings of Švenčionėliai provenance.
Keywords: Pinus sylvestris, forest litter, provenance, ectendomycorrhizae, ectomycorrhizae, mycorrhizal morphotypes, growth parameters, forest nursery.