INFLUENCE OF PEAT SUBSTRATE AND INOCULATION WITH ECTOMYCORRHIZAL FUNGI ON THE ROOT SYSTEM OF NORWAY SPRUCE (PICEA ABIES [L.] KARST.) SEEDLINGS

The effect of commercial peat substrates (AgroCS, Gramoflor) and ectomycorrhizal (ECM) inoculations (Mycorrhiza roots, Mycorrhiza soluble, forest soil, vermiculite, vermiculite inoculum and control) on the root morphology of Norway spruce (Picea abies [L.] Karst.) seedlings was investigated. The experiment set-up was in complete randomized blocks. One block consisted of 12 combinations of inoculation (6 variants) and substrate (2 substrates). The whole experiment consisted of three blocks (repetitions). Lower root tissue density entails higher number of root tips, root forks and specific tips number per weight (STN-W). Higher root volume entails higher root length and average root diameter. Inoculation further enhanced the effect of the substrate where Mycorrhiza roots x AgroCS reached the highest root length (44.85 cm). For the number of root tips, the most significant positive effect was observed in the interaction of vermiculite x AgroCS (161). The interaction of Mycorrhiza roots x AgroCS significantly positively influenced STN-W (11 618). The number of root forks was the highest in the interaction of vermiculite x Gramoflor (173). The lowest values of root tips, root forks and STN-W (80; 85; 5109) were observed in the control x AgroCS interaction. The lowest root length (25.44 cm) was observed in forest soil x Gramoflor interaction. The conditions created by the interaction of Mycorrhiza roots x AgroCS were more favourable for morphological parameters of seedlings roots.