The effect of extractive compounds of spruce greenery on the growth and structural features of Pinus sylvestris seedlings

The results of a two-year experiment on Scots pine (Pinus sylvestris L.) seedlings growing in a forest nursery are presented. Pine seeds were pre-treated with extractives (neutral and acidic components) isolated by emulsion method from spruce green left after timber harvesting. Phenolic acids dominated in acidic components. Essential oils, polyprenols, carotenoids and other biologically active substances are among the neutral components of spruce greenery. We assessed biometric parameters and structural features of seedlings. The intensity of mycorrhization of roots was determined in 1-year-old seedlings, and the elemental composition of needles and the wood density of stems were studied in 2-year-old seedlings. The analysis of pine needles revealed a higher potassium content in the K-Ca pair when acidic components of the biopreparation were applied. This indicates more active photosynthetic processes and transport of assimilates to the plant organs, providing active growth of seedlings in this variant. Acidic components at a dose of 0.5 g/kg of seeds stimulate the growth of seedlings when the process of cell hardening and lignification of increment lags. Neutral components have a positive effect on the formation of the main morphometric characteristics and physical properties of wood. At a dose of 0.012 g/kg of seeds, they increase seedlings preservation in adverse weather conditions. Based on the totality of the studied characteristics, a more in-depth study of neutral components effect is necessary, since neutral components of spruce greenery had a positive effect on seedlings preservation and contributed to both the activation of growth processes and the formation of optimal physical parameters of plants.