Arctic bramble (Rubus arcticus L.) in the Kolyma river valley - seasonal development and bearing

Seasonal development and yield dynamics of the fruits of the arctic bramble (Rubus arcticus L.) were studied in the west of the Magadan Region in the upper reaches of the river Kolyma. The purpose of research is to assess the dynamics of the dates of the onset of the phenological phases of the arctic bramble for the period 2002-2021 and identification of climatic factors affecting fruit yield fluctuations (1992-2021). The tasks of the work included summarizing the data of phenological observations on the populations of the arctic bramble and analyzing the dependence of the dynamics of fruit yield on meteorological indicators and changes in habitat conditions. Phenological observations have been carried out from 2002 to the present; the yield was estimated visually according to the Kapper-Formozov scale (1992-2021). Meteorological observations at the field station of the Institute of Biological Problems of the North FEB RAS have been carried out since 1992. The annual cycle of the arctic bramble (11 phenophases) and the features of the passage of individual stages are described. The seasonal cycle of development of the arctic bramble consists of 5 generative and 5 vegetative phases, the dynamics of the onset dates of which does not show a significant positive trend. For the period 1992-2021 there was a decrease in yield associated with an increase in the frequency of frosts during the flowering period, dry weather in July and changes in habitat conditions. Wild-growing populations of the arctic bramble are a valuable genetic material for breeding work and can be introduced into culture on the territory of the Magadan Region.