Chronobiological aspects of pesticide load optimization in Salix viminalis L. plantings of intensive type

The article considers common osier from the utilitarian perspective and addresses the necessity to applyprolonged-action pesticides in the plantings of intensive type. To reduce the pesticide load, it is proposed to schedule agroforestry activities taking into account the seasonal dynamics of annual shoot growth. The study aims to identify patterns of seasonal dynamics of daily increment of annual shoots of common osier, using such methods as selection, structural-morphological methods, and harmonic analysis. The object of the study is a model inbred population of common osier. It was found that the seasonal dynamics of daily shoot growth ΔL(t) is cyclic. A three-level structure of seasonal biorhythms of daily shoot growth wasdiscovered. The contribution of lower harmonics with the oscillation period of 32 to 96 days to the total cyclicity ΔL(t) was 65%. The contribution of the medium harmonics with the oscillation period of 16 to 24daysto the total cyclicity ΔL(t) was 23%. The contribution of higher harmonics with the oscillation period of less than 14 days to the total cyclicity ΔL(t) was 6%. To optimize the pesticide load in the plantings of common osier, it is recommended to take into account the biorhythms of shoot growth with a frequency of fluctuations from 16 to 24 days.