Variability of roots size and mycorrhization in seedlings of pine (Pinus sylvestris L.) under adaptation to the conditions of inhabitance

To find out the peculiarities of underground parts' architectonics variability which characterize an extent of autonomic and symbiotic adaptation of ectomycorrhizal plants in root zone, the seedlings of Pinus sylvestris L. from 45 natural and artificial localities were studied. At the territory of the Ural region the plants, 1496 samples in total, were picked out from intact forests, burnt forests, natural (arboreta) and non-forest habitats on clay, loam, and peat soils. In the experiments, the tested seedlings were also grown in greenhouse under unsterile conditions using pots filled with the mix of peat and sand to which a sample of woodland sod-podzole soil was added as an inoculum. The length of undetermined roots as an index of autonomic adaptation, and the rate of root mycorrhization as an index of symbiotic adaptation were estimated. Under similar conditions, the individual's variability on mycorrhization was shown to be higher comparing to the variability on undetermined roots length. Both these traits were mostly determined by environmental conditions depending on locality. For root length and mycorrhization rate, the component, related with differences between groups due to locality made 52 and 75 % of the total variance, respectively. Local environment modifications between the habitats within a group of habitat resulted in 14 % (root length) and 7 % (mycorrhization rate) of the total variance. So, from the total variance on these traits 34 и 18 % at most are due to individual variability. These data characterize the ectomycorrhial symbiosis as a coenotic facility to increase a diversity of ectomycorrhizal plants in root zone. Its effect results in qualitative changes in these organs and depends on plenty, activity, and inter- and intraspecial differences of mycobionts.