New source material for improving raspberry assortment in the Central region of Russia

Abstract

The aim of the research is to search new sources of the main economically valuable traits for further breeding of raspberry. Nineteen previously created selected forms were studied for winter resistance components under controlled conditions, for resistance to major fungal diseases, productivity components, strength and biochemical composition of fruits. The zoned Gusar variety was used as the control. The work was carried out in 2018-2020 according to generally accepted techniques. Artificial freezing of raspberry stems was carried out in the climate chamber TH-6 JEIO TECH. According to the results of the studies, selected forms 8-10х-1, 6-125-4, which have an increased resistance to certain components of winter resistance, have been identified. Hybrids 2-115-1 and 1-188-1 have cumulative resistance to winter damage factors. Based on the integrated resistance of raspberry hybrids to the main fungal diseases, new sources have been revealed: forms 1-124-1, 2-115-1, 2-115-2, 1-111-21, 1-8-2, 2-35-1, 2-90-3, 6-125-4, 3-4-2, 8-10х-1, 4-33-21 and 4-122-2. The degree of their damage did not have a significant influence on winter hardiness, productivity and quality of berries. As the result of study of components of the raspberry productivity, selected forms (1-111-21, 2-90-2 and 2-90-3), forming fruits with an average weight of more than 4.0 g, and genotypes with large and one-dimensional fruits (1-176-21, 2-35-1, 4-33-21, 1-124-1) not growing smaller from picking to picking were identified. The highest potential productivity was noted for selections 2-115-1, 1-111-21, 1-188-1, 4-46-2, 2-90-2 and 2-90-3, capable to form a yield of more than 1.3 kg per bush. The selections 1-124-1, 2-90-2 and 2-90-3 are distinguished by an increased strength of the fruits. They form fruits with a crushing force exceeding 5.0 N, which ensures the safety of integrity and transportability when manually harvested. No complex sources of increased accumulation of biologically active substances have been identified. Genotypes with a high content of individual biochemical substances were selected. The highest accumulation of soluble solids and sugars was noted in the samples 2-90-3, 18-11-4 and 2-115-1. Highest accumulation o the vitamin C was observed in the samples 6-125-4 (59.8 mg/100 g) and 2-90-3 (61.5 mg/100 g). As new sources in breeding to improve the taste characteristics of raspberry, it is necessary to use selected forms 2-90-2, 2-115-1 and 6-125-4, approaching in taste to the standard variety Novost Kuzmina. Selected forms 2-90-2, 2-90-3 and 2-115-1 are new sources in raspberry breeding, combining a complex of economically valuable traits at a high level.