EMERGENCE, SURVIVAL AND ROOT SYSTEM OF SCOTS PINE (PINUS SYLVESTRIS L.) SEEDLINGS IN DIFFERENT LIGHT INTENSITIES AND IRRIGATION REGIMES

The effect of different light conditions (100%, 50-60% and 20-30% of full light) and different irrigation regimes (480, 360, 240 and 120 mm during vegetation season) on the emergence, growth, survival and root characteristics of Scots pine (Pinus sylvestris L.) seedlings of 5 Czech provenances was investigated. Full-light conditions resulted in the lowest survival rates (10-25%) across all irrigation variants, while the highest survival rates (50-70%) were found in semi-shade conditions for all considered provenances. Generally, the root lengths, shoot dry mass and root dry mass were the highest in full-light conditions, on the contrary the shoot-root ratios for both the above and below ground plant lengths (0.19-0.35 in full-light versus 0.70-0.83 in full-shade conditions; F-(11,F- 108) = 92,6; p < 0,001) and dry mass (1.1-2.1 in full-light versus 3.3-4.9 in full-shade conditions; F-(11,F- 108) = 146.1; p < 0,001) were the lowest. Conditions resembling shelterwood regeneration were more favourable for seedling emergence, root characteristics were more favourable in conditions simulating clear-cutting.