Dynamics of development of <i>Salix triandra</i> shoots on saplings from basal and apical cuttings
Purpose of research is to identify the patterns of development of shoots on annual saplings of S. triandra grown from cuttings taken from different parts of uterine shoots. Research methodology and methods. The object of the study is a model inbred-clonal population of S. triandra . Experimental group: replicas of eight clones. Variants for each clone: annual saplings grown from basal and apical cuttings. All variants were carried out in three replications. Material: growing annual shoots. The research was doing out in the soil-climatic conditions of the Bryansk district of the zone of broad-leaved forests. Observations were conducted against the background of excessive atmospheric moistening during the rooting of cuttings. Methods: chronobiological, numerical analysis of time series. Results. The seasonal growth of shoots on basal cuttings was 148-219 cm, on apical - 95-171 cm. The maximum daily increment of shoots on basal cuttings is 2.59 ± 0.148 cm/day, on apical - 1.86 ± 0.085 cm/day. The highest values of the daily increment of shoots on basal cuttings were revealed in middle of June, on apical cuttings - in middle of July. The duration of multi-day cycles of daily increment was 16-26 days, regardless of the clone factor and the origin of cuttings. The maximum number of multi-day cycles does not exceed 5. On the shoots of clones with the highest daily increment, the number of multi-day cycles decreases to 3-4. Scientific novelty. Under the conditions of this experiment, the cyclical development of all the studied shoots of S. triandra was established. Multi-day cycles of daily increment are highly synchronized in the first half of the vegetative period, regardless of the clone factor and the origin of cuttings. The range of fluctuations in the daily increment of shoots on basal cuttings is determined primarily by the clone factor. The same range of oscillations on apical cuttings is largely determined by intraclonal variability. To create plantings of S. triandra , it is recommended to use, first of all, cuttings from the basal parts of shoots. If there is a shortage of planting material, it is permissible to use the tops of shoots, taking into account the factor of mother clones.