Epigenetic and macrophysiological regulation of vegetative progeny crown morphogenesis of Siberian stone pine trees (Pinus sibirica Du Tour, Pinaceae) of different age
The influence of epigenetic (associated with the ontogenetic meristem maturity) and macrophysiological(related to the rootstock influence) factors on the age-related variability of Siberian stone pine crown morphogenesis hasbeen studied. The objects of study are 6-year-old vegetative progeny of juvenile (3–5 years), immature (20–60 years),generative (200–350 years) and senile (350–700 years) trees of different age (grooving in southern taiga subzone, north ofthe Ob-Tomsk interfluve) grafted onto a common young stock. The prevailing trends in the formation of the grafts crownare revealed: the closer the donor tree is to the ontogenetic peak of growth, the more intensively its vegetative progenygrows and branches. The observed differences in growth and branching trends of grafts resulted in the formation of anage-specific crown shape: juveniles slowly grew but actively branched, immature actively grew and actively branched,generative actively grew, but worse branched, senile equally poorly grew and branched.