Growth and seed production of siberian cedar pine in introduction crops of plantation type in Moscow region

Abstract

For Siberian stone pine, seed production and the possibility of selection based on seed production traits during introduction largely depend on growing conditions. We studied growth and seed production in introduced plantation-type crops with a planting density of 0.4 thousand pcs/ha. There was no competition for light between the trees in the crops, which contributed to the maximum development of the crown and generative organs. The studies showed that the plantation is characterized by high preservation and good condition of the trees. The trees develop a wide crown extending to the ground and enter the generative stage of development early. Most parameters of cones and seeds in the introduced population differ little from those in the species range, with the exception of the number of seeds in a cone, which is lower in the studied crops. That can be explained by the youth of the plantation, insufficient pollination and a high level of self-pollination. The most variable trait was the number of cones on a tree. This feature can be used in selection for early entry into the seed-bearing stage and high seed productivity. It was found that trees of different sexual types differed in the number of cones on the tree and the percentage of full-grained seeds in the cone. When conducting selection activities, preference should be given to trees with female sexualization and trees producing a relatively large number of generative organs of both sexes. It is advisable to leave trees of male sexualization in the plantation to ensure cross-pollination.