Scientific publications

We studied seasonal dynamics of arginine content in young and one year old needles of 10 year old Scots pine (Pinus sylvestris L.) under natural regeneration and under intensive nitrogen (300 kg ha-1) and optimal boron (3 kg ha-1) treatment. Control species contained the aminoacid in similar amounts in fresh and one year old needles (0.7+0.1-1.3+0.1 qmol g-1 of oven-dry matter) having maximum concentration in May. Nitrogen and boron treatment of soils have increased the arginine content in the needles, with exceptionally high increase in fresh ones. Its concentration was high in fresh and one year old needles from July to May, with the maximums in September (618+60.4 и 152+14.8 qmol g-1 of oven-dry matter in fresh and one year old needles, respectively). Accumulation of arginine in needles was caused by excessive uptake of nitrogen likely as the result of inhibition of catabolism of the aminoacid by boron. Mechanisms of nitrogen and boron impact on seasonal variations of arginine accumulation are discussed. We conclude that nitrogen and boron treatment of Scots pine is an effective method to get arginine-enriched needles over the season after fertilization.