Study of frost resistance of own-rooted and grafted cherry plum under controlled conditions

Abstract

Studies on the frost resistance of cherry plum were carried out in 2022-2023 at the Federal Horticultural Research Center for Breeding, Agrotechnology and Nursery in laboratory conditions by artificial freezing in the climatic chamber EW 1070. The objects of research were plants of the varieties Shatyor, Zlato Skifov and Kubanskaya Kometa, own-rooted and grafted on clone rootstocks SVG-11-19 and 13-113. The purpose of the research is to study the influence of the method of reproduction and the shape of the rootstock on the frost resistance of buds and tissues of annual branches of cherry plum and to identify the most frost-resistant graft-rootstock combinations. It was found that after freezing at t = -30 °C, more than 50 % of generative rudiments remained viable in both years of research in the Kubanskaya Kometa variety, in the Zlato Skifov variety – from 30 to 45 %, in the Shatyor variety – on average 49 %. The limits of changes in the frost resistance of generative buds of varieties depending on the rootstock are shown: in the Kubanskaya Kometa variety – from 46,5 % (13-113) to 68,9 % (SVG-11-19), in the Zlato Skifov variety – from 37,6 % (own-rooted) to 45,3 % (SVG-11-19), and in the variety Shatyor – from 41,4 % (roots) to 45,3 % (SVG-11-19). When using the clone rootstock SVG-11-19, the safety of generative rudiments increased by 17 % compared to the root variant. Damage to vegetative buds and tissues of annual branches up to 1-3 points was caused by temperature t = -35 °C. The most frost-resistant combinations were the Kubanskaya Kometa/SVG-11-19 and the Shatyor/SVG-11- 19, in which kidney and tissue damage was less than 1 point.