Economic and biological indicators of clonal rootstocks of apple trees in conditions of the Astra-khan region

Abstract

The task of modern nursery farming includes the proper selection of high-quality one-year-old seedlings grafted onto medium-sized clone rootstocks. The research was conducted at the fruit orchard of the Federal State Budgetary Scientific Institution "Pre-Caspian Agricultural Federal Scientific Center of the Russian Academy of Sciences" in 2020-2022. A trial of apple varieties Aidared, Vishnevaya, and Welsi, grafted onto rootstocks of varying growth vigor M9 (dwarfing), P60 (dwarfing), 62-396 (semi-dwarfing), and 54-118, SK1 (medium-sized) was carried out. The control was M9 rootstock series. The aim of the research was to study and identify seedling rootstocks of stone fruit crops that are most adapted to the conditions of the Northern Caspian region, ensuring the cultivation of high-quality planting material. As a result of the study, it was established that the survival rate of cuttings in the first field of the nursery ranged from 82.0 to 90.0%, with low survival rates observed for the control M9, 62-396, and SK1 (16.3  to 49.8%). Grafting success rate was 95.8 to 100%. Prior to grafting, the thickness of the root collar for 62-396 and 54-118 rootstocks reached 11.2-11.9 mm, significantly exceeding the values of the control (10.3 mm). Practically all rootstocks demonstrated high graft survival rate (100%). The medium-sized rootstock 54-118 showed high yield of the first-grade seedlings (100%). The diameter of the trunk in one-year-old seedlings dug up in autumn was 1.2-1.6 cm, height was 91.0-146.4 cm, and the length of the root system was 18.0-22.7 cm.