Kyrylko Y. Agroecological aspects of the creation of poplar (Populus L.) energy plantations in the conditions of the Right Bank Forest Steppe of Ukraine

According to the results of studies of the features of the creation, growth and productivity of poplar plantations in the conditions of the Right Bank Forest Steppe, it was established that to increase the survival rate of cutting seedlings of poplar varieties 'Dorskamp', 'I-45/51' and 'Robusta', it is necessary to plant them without the aerial part. It was established that the viability of the planting material changed depending on the weather conditions of the growing season and partially - on the type of planting material. Among the investigated poplar cultivars during 2020-2021, the higher rates of grafting of cuttings seedlings were in the case of using seedlings with cut trunks - from 57.0±3.01 to 68.9±2.90%. Seedlings with an aerial part took root worse - from 50.3±2.40% to 68.1±2.71%. During the growing season of 2022, the highest survival of seedlings was in the variety 'Robusta'. It was 74.4±4.62% in seedlings with removed trunks and 88.9±3.33% - with trunks. In the rest of the studied varieties, the survival rate of both types of planting material was almost the same. In plants of the 'Dorskamp' variety, it was 81.1±4.15 and 82.2±4.05%, respectively, and in I-45/51 - 77.8±4.41 and 75.6±4.55, respectively %. It was established that the average height of plants after the end of the first growing season was higher in the vast majority of cases in seedlings with the trunk removed. At the same time, plants of the 'Dorskamp' clone had the highest height - 189.5±3.45 cm. In unpruned plants of this variety, it was 174.0±7.69 cm. The increase in height in seedlings with a trunk was very small and amounted to 4 .6 to 17.7 cm. The results of similar studies, which were conducted during the growing season of 2021, showed that the indicators of preservation and height were slightly higher, but in general, the general trend observed in 2020 was preserved. The growth of seedlings with trunks in 2021 was higher, compared to 2020 - from 17.8 cm in the variety 'Robusta' to 31.1 cm - in 'Dorskamp'. Accordingly, their average heights turned out to be higher. At the same time, in the case of the 'Dorskamp' variety, seedlings with trunks were slightly higher - 190.4±7.93 cm against 188.6±4.15 cm when using seedlings with the trunk removed. The 2022 study generally confirmed the conclusions reached in previous years. The highest height indicators at the end of the growing season in 2022, as in previous years, were found in plants of the 'Dorskamp' variety. When using seedlings with trunks, the height was 197.2±6.61 cm, and without trunks - 209.3±5.62 cm. The weather conditions of 2022 were the least favorable for the growth of plants of the 'I-45/51' variety. Their average height at the end of the growing season was 134.1±4.31 cm when using seedlings with trunks, and 135.9±4.94 cm without trunks. In plants of the 'Robusta' variety, the average height of plants from seedlings with trunks in 2022, for the first time during the years of research, turned out to be slightly higher than the indicators of seedlings without trunks (160.1±5.09 and 155.6±5.91 cm, respectively).