Development of primocane-fruiting raspberry varieties in the conditions of forest-steppe zone of the Irkutsk region

Heightened interest in primocane-fruiting raspberry in the region necessitated a detailed study of this berry crop. The article introduces the research carried out in 2019 on the 0.15 ha collection site of Siberian Institute of Plant Physiology and Biochemistry of the Siberian Branch of the Russian Academy of Sciences (Irkutsk). The research objects were 9 varieties and 3 select forms of primocane-fruiting raspberry of the domestic breeding. Particular attention was paid to the biological and practical features of the research object: early maturity, cropping power, and damage caused by phytopathogenic objects. During the growing season, the varieties bearing fruit in late July - early August and those bearing fruit in the first and second ten-day intervals of September were noted. Large-fruited varieties (fruit mass more than 6 g) and large-fruited forms (fruit mass more than 7 g) were singled out. In the study season, fruiting continued until early October due to weather conditions. That allowed many plants to give maximum yield. The last harvest was on October 7, 2019. However, there were some plants that were only entering the stage of mass bearing at that moment. As a result, more early-maturing forms and varieties with the highest cropping power and resistance to fruit rot during the rainy season were registered among the range of varieties under study. Observations on the spider mite population on the plants were described. The paper describes the conditions for growing and the difficulties encountered during the planting of primocane-fruiting raspberry. The climatic conditions of the study area are described.