Відбір і збереження плюсових дерев cосни звичайної в умовах Чернігівського Полісся та лісостепової частини України

• Datum: 2023
• 1. Verfasser: Tereshchenko, L. I.
• Format: Artikel
• Sprache: Ukrainisch
• Veröffentlicht: Ukrainian Research Institute of Forestry and Forest Melioration named after G. M. Vysotsky (URIFFM) 2023
• Schlagworte: Pinus sylvestris L.; показники росту; якість стовбура; селекційне оцінювання дерев; стан плюсових дерев
• Online Zugang: https://forestry-forestmelioration.org.ua/index.php/journal/article/view/390
• Назва журналу: Forestry and Forest Melioration

Introduction Most modern methods of forest tree improvement are based on the method of selecting the best trees for further propagation and use. Currently, there are 4.600 plus trees in the State Register of Ukraine, of which more than 1.300 are Scots pine trees. Current tasks are monitoring their condition as well as their evaluation and involvement in seed production programs. Plus trees are intended for vegetative and seed reproduction and the creation of progeny tests, clone archives, and forest seed orchards on their basis. Assessment of the breeding value of the Scots pine plus trees after a long period from the time of selection is of great significance in improving forest selection methods. The research aimed to analyze the primary and present characteristics of Scots pine plus trees as objects of conservation in situ in Chernihiv Polyssia, the Right-Bank, and Left-Bank Forest-steppe, and improve approaches to the selection of plus trees, as well as provide suggestions for increasing the selection efficiency. Materials and Methods The results of the present survey of 80 plus trees of Scots pine (Pinus sylvestris L.) selected more than 35 years ago in the stands of Chernihiv, Kharkiv, and Cherkasy regions are presented. Growth and quality characteristics, selection category, condition, and reproduction intensity were determined. The data obtained during the survey have been compared to the data from the Passports of plus trees at the year of selection. Results The study showed no clear trend like changes in the growth variables of plus trees. According to the survey results, 95% of the Scots pine plus trees in Chernihiv region retained their advantages in height, and 92% of them in diameter 36–48 years after their selection. In Kharkiv region, the values for the Scots pine plus trees were 73% and 55% respectively. Most plus trees had high-quality trunks; in particular, the value was 95% in Chernihiv region, 94% in Cherkasy region, and 73% in Kharkiv region. The average length of the knotless part of plus trees’ stem from their total height was 70%, 56%, and 43% respectively. The least quality trunks were surveyed in plus trees in Kharkiv region. There is a tendency for the plus tree condition to deteriorate with age. Approaches to the selection of Scots pine plus trees were analyzed, and it was proposed to measure at least 10 trees surrounding a candidate plus tree or the five best trees selected within 100 m from it on plots with hilly terrain and in a mixed stand. To confirm the uniqueness of the candidate tree, it is advisable to attach its photo in addition to a detailed description. Conclusions The percentage of the excess of the plus trees growth variables over the average values of the surveyed stands have decreased with age to 3–9% in height and to 3–13% in diameter. The majority of surveyed plus trees had high-quality trunks. The tree height and trunk straightness were determined as the most important indicators for the selection of plus trees. Approaches to the selection of Scots pine plus trees were analyzed and proposals for improving the selection criteria were provided. It is recommended to reduce the requirements for plus trees in terms of self-pruning in Forest-Steppe conditions compared to Polissia. It is proposed to create an electronic database of detailed protocols for the plus tree selection and characteristics of their genotypes, as well as to conserve all selected plus trees in ex situ. 2 Figs., 4 Tables, 19 Refs.