Adaptive responses of scots pine to the impact of adverse abiotic factors on the rhizosphere

The impact of long-term seasonal soil freezing, drought, and waterlogging on the rhizosphere of young Scots pine trees (Pinus sylvestris L., age class 1) has been simulated in experiments. The results have shown that cold stress exposure leads to reduction of the rates of linear and radial tree growth and of chlorophyll content in needles, a shift in the peak of starch content, and initiation of free amino acid deposition in the aboveground plant parts. Drought activates utilization of carbohydrate reserves and amino acid accumulation in the root bast, whereas soil waterlogging stimulates deposition of carbohydrates but causes a decrease in the levels of chlorophyll and amino acids in all plant tissues.