Study of the stem growth of heteroplastic grafts of stone pines in the Krasnoyarsk forest-steppe

Abstract

Changes in the radial growth Pinus sibirica Du Tour and Pinus cembra L. grafts and Scots pine (Pinus sylvestris L.) rootstocks were observed in comparison with control (non-grafted) trees of the corresponding species, whichindicated the mutual influence of the grafting components on each other. The smaller width of the annual rings in Pinuscembra grafts compared to Siberian cedar grafts is due to their species features. In general, the phloem was more conservative in structure than the xylem and in the grafts union zone retained the species characteristics, sometimes manifestedin the form of jagged junction of two types of bark, while in the xylem in the union zone were cells with an intermediatestructure. The study of seasonal dynamics showed that, in comparison with the rootstocks of Scots pine (Pinus sylvestrisL.), the scions of Stone pine quickly passed to the process of maturation of tracheids, especially the scions of Pinus sibirica Du Tour, which also completed the development of xylem annual ring faster. The similarity of some parameters of theanatomical structure, reactions to climatic conditions, synchronization of the development of the annual ring in the scion of the P. cembra with the stock of the Scots pine explain the higher safety of grafts of the P. cembra in comparison withthe P. sibirica.