Growth and formation of cones of 56-year-old Siberian Cedar trees in geographical plantings

The variability of the Siberian cedar in terms of the intensity of growth and yield, growing on the site “Continuation of the geoschool” in the suburban area of Krasnoyarsk, is considered. The trees were grown from the seeds of the Tanzybei (Krasnoyarsk Territory) and the Altai (Altai Republic) populations. The layout is 4×4 m. The height, diameter of the trunk, crown, and the number of cones on the tree have been determined. It was found that the average height of trees of different geographical origin is 11.5 and 12.9 m, the trunk diameter is 24.6 and 25.2 cm, respectively. The level of variability of growth indicators is medium and high. The number of cones on the tree ranged from 10 to 159. Trees were selected that differ in growth intensity and yield for the cultivation of selective planting material.


1.Introduction
The study of the polymorphism of woody plants is one of the main measures for the preservation of their biodiversity. Within the range, natural populations of Siberian cedar are characterized by high genetic potential, which is the basis for the selection and further breeding research.
Creation of geographical cultures of woody plants allows to identify the most productive populations and forms for collecting seeds and efficient cultivation of this species under certain growing conditions [1,2,3,4].
Geographic cultures of the main forest-forming species have been created abroad since 1887, and in Russia since 1896. Indicators of geographical crops are a characteristic of the success of the growth of offspring and help identify the differences between them when growing in new conditions. According to the literature, it was established that crops from local seeds were more stable and productive. A promising selection of seeds in some populations is noted. The offspring of these populations is distinguished by high rates of growth and productivity. At the same time, the boundaries of seed transfer in latitudinal and longitudinal directions were determined [5, 6]. Thus, M A Nikolaeva et al. [7], after the researches on the growth of the offspring of 26 climatypes in 48-50-year-old geographical cultures of Siberian larch in the Republic of Bashkortostan, found that it is advisable to use seeds of this species with their transfer from the south to 2 °, northup to 1 °, eastup to 3 ° 40 ′. They note that the permissible difference between the heights above sea level in the places where the seed is harvested and, in the area, where crops are created should not exceed 500-550 m.
B According to S V Manzo et al. [15], in the geographical cultures of the Greg pine in Mexico, created in 1997, the interaction of the genotype with environmental conditions manifested itself in all growth parameters.
When studying the variability of the Siberian stone pine in geographical cultures in the Moscow region [16,17], the Krasnoyarsk Territory [18, 19], a high polymorphism was noted in the offspring of the populations, and the best forms were identified. Nevertheless, the individual and geographic variability of Siberian cedar seed production in geographic cultures under specific forest conditions requires a long study period [20,21,22].
The purpose of the research is to study the variability of 56-year-old cedar of Siberian Altai and Tanzybei origin in terms of growth intensity and cone formation, growing on the site of the Siberian State University arboretum "Continuation of Geoschool" in the suburban area of Krasnoyarsk.

2.Objects and methods
The site and characteristics of the maternal populations used for collecting seeds with subsequent cultivation of offspring are shown in table 1. In the place of growth, the maternal plantings differ insignificantly. They are included in the South Siberian mountain forest zone of the Altai-Sayan mountain-taiga region. The most productive is the plantation growing on the territory of the Tanzybei TIE (bonitet class II versus III in Karakokshinsk TIE).
The collection of seeds in these plantings was carried out in 1964, the transplantation of seedlings to the school department -in 1966, to the permanent place -in 1983 (planting scheme 4x4 m).
In the fall of 2019, biometric indicators were determined for the Siberian cedar at the age of 56 years old: height, trunk diameter at a height of 1.3 m, crown diameter, as well as the number of cones on the shoot, on the tree. Correlation analysis between the studied indicators was carried out. The specimens distinguished by intensive growth and increased productivity were identified. The research results were processed statistically using the Microsoft Office software package.

Results and discussion
The level of variability of growth indicators of Siberian cedar of different origin from medium to high was found (table 2). The height and diameter of the trunk and crown have large indicators in the offspring of the Altai population, however, the difference between them is not confirmed statistically (tf <t05).
All trees at the age of 56 have formed cones, however, there is a large difference in their number on a tree: in the Altai version -from 2 to 42 pcs., In the Tanzybei version -from 10 to 159 pcs.
The number of cones in a bunch (on the shoot) varies from 1 to 3 pcs. The largest number of threecone trees (25.0%) was observed in trees of Tanzybei origin in comparison with Altai (16.7%).
The specimens were selected according to the intensity of growth and the formation of cones (table  3). The largest diameter of the trunk, crown and the number of cones are noted in trees with numbers 68-4, 74-8 of Altai and 72-5, 70-6 of Tanzybei origin. Their number of cones exceeded the average value by 2.1-4.9 times.
It should be noted that the selected trees 74-8, 72-5 and 70-6 belong to the multi-cone form (the maximum number of cones "in a bunch" is three). For tree 68-4 of Altai origin, the maximum number of cones on the shoot was 2 pcs.

Conclusion
Trees 72-5 of Tanzybei origin and 68-4, 74-8 of Altai origin, which are recommended for reproduction by grafting and obtaining clone varieties with increased seed productivity, have the greatest breeding value. Trees which are characterized by growth intensity and yield have been selected for the purpose of the selective planting material cultivation.