МЕТАМЕРНАЯ ИЗМЕНЧИВОСТЬ ДЛИНЫ МЕЖДОУЗЛИЙ SALIX TRIANDRA (SALICACEAE)

Abstract

The article presents the praxeological characteristics of the three-stalked willow (Salix triandra, genus Salix, family Salicaceae). Object: inbred model population of S. triandra. Material: annual shoots obtained on the same seedlings in different years from vegetative buds of different localization. Methods: comparative morphological, chronobiological, ontogenetic, analysis of the series of dynamics. Purpose: to describe and analyze the patterns of ontogenetic variability of the length of internodes on annual shoots. Results. The general variability of the length of internodes is determined, first of all, by their intra-shoot variability. Interannual differences in the length of internodes on shoots of two- and three-year-old seedlings are determined, first of all, by differences in the lower third of the shoots. No significant intracrown differences in the length of internodes were found on shoots of one year. The periodicity of the metameric dynamics of the length of internodes has been established. The interannual specificity of the series of metameric variability of the length of internodes is associated with the age of root-butt systems. The metameric variability of the length of internodes with different reliability is approximated by linear regression equations. Rhythm in metameric variability of deviations of internode length from linear trends was revealed. The graphs of the series of deviations in the length of internodes from linear trends are presented in two versions - either with two or with three peaks, which indicates the discreteness of the trajectories of shoot morphogenesis. The revealed bivariance of the trajectories of shoot morphogenesis is associated with different ages of perennial root-butt systems. Discussion and conclusions. The bivariance of shoot morphogenesis is not directly related to adaptations to environmental conditions and is determined not by genetic differences, but by epigenetic mechanisms. Hypothesis: the most probable reason for the bivariate morphogenesis of shoots is the ontogenetic heterogeneity of vegetative buds from which these shoots develop. To verify the hypothesis put forward, an experiment was proposed to study the metameric variability of the length of internodes of shoots obtained from terminal and axillary buds in the same year.