Variability of half-sibs of plus trees of Siberian pine at the age of 30-35 years in terms of growth indicators

• Main Authors: Rimma Matveeva, Olga Butorova, Vladimir Narzyaev, Iuliia Shcherba
• Format: Article
• Language: English
• Published: Ukrainian National Forestry University 2020-12-01
• Series: Наукові праці Лісівничої академії наук України
• Subjects: siberian cedar pine; forest seed plantation; family; seed productivity; stem productivity; selection; siberia.
• Online Access: http://fasu.nltu.edu.ua/index.php/nplanu/article/view/629
• ISSN: 1991-606X; 2616-5015

The preservation and development of the genetically valuable potential of conifers is achieved through the creation of forest seed facilities, including forest seed plantations, which are designed to obtain improved seeds. The data on the variability of Siberian cedar pine (Pinus sibirica Du Tour) half-sibs on the forest seed plantation “Ermaki” located in the Ermakovsky administrative region on the south of the Krasnoyarsk region are presented. The aim of the study is to analyze the variability of the seed progeny of Pinus sibirica at the age of 30-35 years. The objects of research were the half-sibs of plus trees 13/13, 17/17, 18/18, certified by stem productivity, and 86/50, 89/53, 90/54, 99/63, 103/67, 109/73, 110 / 74 - certified by seed productivity. Half-sibs are grown from seeds of 1984 sowing. Planting of plants was carried out according to the scheme 8 × 8 m. The variability of seed progeny indicators for plus trees was compared for a five-year period. The variability of height, diameter of trunk, diameter of crown, length of needles was analyzed depending on the genotype and the principle of selection of plus trees. Studies have shown that the average height of families at the age of 30 was 5.1-6.2 m. Half-sibs of families 17/17 in stem productivity and 89/53, 103/67 in seed productivity were distinguished by intensive growth (the excess was 10.7-21.6%). The largest trunk diameter was noted in families 17/17 by stem productivity and 90/54, 89/53 – by seed productivity. The average crown diameter of 30-year-old half-sibs of plus trees, selected by seed productivity, is 2.4 m, which is 20.8% more than by stem productivity. By the age of 35 years, the height of the families was 6.3-7.6 m with a trunk diameter of 16.4-21.2 cm. The trees of the 89/53 plus tree family are distinguished by the highest seed productivity, which significantly exceeds the values of this indicator over the offspring of 13/13, 86/50 and 109/73 plus trees. Other families differ slightly from the best option. Some half-sibs in families reach a height of 9.1-9.6 m. The average diameter of the crown of trees by the age of 35 in the studied families increased to 3.2 m. The coefficient characterizing the ratio of crown diameter to trunk diameter with free placement of trees on the plantation was 15.6-18.4, that is, the difference between families is 1.2 times. The greatest excess of the crown diameter over the trunk diameter was manifested in the progeny of the 99/63 plus tree in terms of seed productivity. The greatest length of needles (11.5-11.6 cm) was distinguished by half-sibs in families 17/17, 18/18 and 99/63. The maximum length of needles (14.0 cm) was recorded in the 10-21 half-sib in the 90/54 family of seed productivity. Comparison of families of plus trees by a set of parameters indicates that the seed offspring of plus trees are distinguished by the best growth in terms of seed productivity. Families and half-sibs were selected according to the intensity of growth, the length of the needles. These half-sibs are recommended for further propagation by grafting in order to plant forest seed plantations.