The influence of the types of cassettes and containers on the biological productivity of the planting material of the hybrid Populus alba L. Populus tremula L. has been studied.

In the context of shrinking forests in the world, the issue of rapid reforestation is becoming relevant, for which it is necessary to select an assortment of forest tree species with improved hereditary qualities and high growth rates. To obtain high-quality forest plantings in the shortest possible time, it is promising to use planting material with a closed root system, which makes it possible to increase the survival rate of plants to 100% during planting. The objects of the study were specimens of the hybrid Populus alba L. x Populus tremula L., propagated under in vitro conditions in the laboratory of PCR analysis of the Research Institute of Innovative Technologies and the Forest Complex at the G.F. Morozov Voronezh State University of Forestry and Technologies. The research was conducted in the period from May 2024 to November 2024 on the territory of Joint Stock Company Nursery Complex of the Voronezh Region: 5A Uchebny Kordon str., Voronezh, 394087, Voronezh Region. In the course of the study, the biological productivity of plants grown in different types of containers in the greenhouse and in the hardening area was determined. Biometric measurements of the planting material included: determination of height, diameter, dry weight of the stem and root, number of leaves, root length of the studied plants. As a result of statistical processing, it was found that plants grown in Hiko V-150 and Hiko V-265 containers showed the best result in biometric indicators, the worst in Hiko V-120, seedlings in P9 containers occupy an intermediate position, but do not provide rational use of the area. For the production of large-sized seedlings of the hybrid Populus alba L. x Populus tremula L. In June, it is recommended to transplant plants from cassettes into technological pots of 2 liters. Seedlings of this type are more efficient to grow in a greenhouse, however, it should be borne in mind that it is better to plant such planting material in the spring, since plants do not undergo hardening phases.