Home – Home – Jornals – Siberian Journal of Forest Science 2017 number 1

We studied the peroxidase activity during the period of active cambial growth in two forms of 8-year-old Silver birch trees with different degrees of manifestation of wood grain figure: Betula pendula var. pendula and Betula pendula var. carelica. We selected leaves from short shoots and leaves from long shoots, small roots, xylem and phloem for the analysis. It was determined that peroxidase activity in B. pendula var. carelica was higher than in B. pendula var. pendula. The more the degree of manifestation of wood grain figure was in Betula pendula var. carelica, the more the peroxidase activity in xylem was. It was suggested that local violation of cambial activity in Betula pendula var. carelica leads to increased quantity of reative oxygen species and it can enhance the peroxidase activity. To identify the response of birch plants under the excess of nitrogen fertilizers, we studied the influence of nitrate on the peroxidase activity. This investigation was made for the first time. Application of nitrate had led to the increase in the peroxidase activity in xylem and phloem only in Betula pendula var. carelica. In Betula pendula var. pendula the peroxidase activity in xylem and phloem has not changed under the application of nitrogen fertilizers. Application of KNO₃ gave multidirectional changes in leaves in both forms. Peroxidase activity in B. pendula var. pendula increased, but activity of the enzyme in B. pendula var. carelica decreased.