IMPROVING THE PERPETUAL RASPBERRY ASSORTMENT FOR THE NORTH CAUCASIAN REGION OF THE RUSSIAN FEDERATION BY DRAWING ON THE BIOLOGICAL POTENTIAL OF VIR COLLECTIONS
For raspberries (Rubus idaeus Focke), one of the most valuable and popular berry crops in Russia, it is important to study the genotypeenvironment interaction. The complex genomic composition of modern varieties of this crop, the modifying influence of climatic growing conditions on the manifestation of variable traits that affect the marketable fruit yield, necessitate an assessment of the varieties available in the collection in order to identify the most optimal ones for specific agrobiological conditions of the region chosen for crop cultivation. During a three-year (2017-2019) study of ten accessions of perpetual and semi- perpetual raspberries of domestic and foreign breeding accumulated at the Krymsk EBS, a branch of VIR, biological features of the phenophases of raspberries seasonal growth and development were observed concerning the following characters: the number of berries; average, minimum and maximum berry weight, as well as the total and marketable yield. The purpose of this work was to select high-tech varieties of perpetual raspberries for commercial plantations in the North Caucasus region of Russia by selecting the optimal ones with a complex of economically important traits, from those available in the VIR collection of plant genetic resources. A quantitative assessment of the influence of the variety genotype, of the conditions of the year of cultivation and their combined effect on the studied characters was carried out using the two-factor analysis of variance. It was shown that varietal characters have the greatest effect on the commercial productivity of the bush (the share of the “variety” factor influence is 68%), while weather conditions influence it to a lesser extent (the share of the “year” factor influence is 7.5%). Generalization and complex analysis of the data obtained in the course of this work showed that a combination of economically important traits was exhibited by the studied varieties ʻBryanskoe Divoʼ, ʻHerculesʼ, ʻNikaʼ and ʻAnteyʼ, which can be recommended for large-scale production trials. The use of the rapid clonal micropropagation of raspberries of perpetual fruiting type makes it possible to obtain a sufficient number of plantlets for laying out industrial variety trials for one to two years after the introduction into the culture, which, as a result, accelerates the introduction of new varieties into production.