The Content of Reserve Nutrients in the Cells of Annual Shoot Tissues of the Representatives of the Spruce (Picea L.) Genus in Nizhny Novgorod Region

Abstract

The crucial issue of modern age is creation and maintenance of an ecologically friendly environment in urban areas. One of the ways of its solution is adaptive selection of tree and shrub species (both natives and exotic) used for green construction. The performance of this work depends on the application of scientific knowledge about the ecological and physiological state of each species. This determines the need for assessment of adaptive capacity of the speciess used for greening. An important role in the formation and development of trees and shrubs, including members of the spruce (Picea A. Dietr.) genus, plays the content of reserve nutrients in the tissues. A sufficient number of them promotes active growth and development of the shoot, rooting of cuttings and resistance to unfavorable external factors. The research subjects were two species of the spruce (Picea A. Dietr.) genus: indigenous species - Norway spruce (Picea abies L.) and introduced species - blue spruce (Picea pungens Engelm). The starch content in the cells of annual shoot tissues was revealed by qualitative reaction solution (Lugol's iodine); fats were recorded with Sudan III. After staining with appropriate reagents and fixation, cuts were analyzed with a microscope. The assessment of the reserve substances content was given on the cross-section of the scion for each accounting area separately and in the total score for all accounting areas using the 6-point scale we proposed. It was found that the cells of blue spruce tissues contain more reserve substances than the cells of Norway spruce tissues on all accounting dates. The significance of these differences was confirmed by the two-way analysis of variance. The inertia of photosynthesis with a change in temperature is noted. The fat content may be an indicator of the status of a plant and its readiness for the growing season or to transition into resting state. The data obtained allow optimizing the work in the nurseries and rooting of cuttings more effectively.