Structural analysis of the rhythms of development of annual shoots of almond willow

Given the complex characteristics of almond willow. The problems of cytogenetics of this species are described. The possibility of apomictic reproduction is proved. The need to identify endogenous rhythms that determine the cyclical dynamics of the seasonal growth of annual shoots is substantiated. Empirical data were obtained using aligned genetic material cultivated under homogeneous conditions. An original algorithm of material processing using harmonic analysis is proposed. The seasonal dynamics of the main parameters of the growth of shoots: the length of internodes and the average daily number of internodes — is analyzed. Installed quasi-periodic nature of the cycle of the seasonal dynamics of parameters of growth of shoots. On the basis of the available material, the basic series of parameters dynamics combining shoots with visually similar rhythms of development are identified. The possibility of using amplitude–frequency analysis to identify the main groups of biorhythms that determine the dynamics of shoot growth is proved. The main and modulating influence of endogenous rhythms with different periods of oscillations on the seasonal dynamics of shoot parameters is established. Seasonal trends of changes of parameters of growth of the shoots are determined by the low harmonics of the fractional periods of the oscillations. The main contribution to the cyclical development of shoots makes harmonics with a period of oscillation of the order of one month: 24 and 36 days. Harmonic with the oscillation period of 11 ... 22 days to form quasi-cyclic components of the seasonal dynamics. The obtained results are recommended to be used in the development of scientific bases for the creation of willow plantations of three–stamen intensive type