Structural and functional needle features of Pinus sibirica Du Tour grafting depending on the ontogenetic age of the donor trees

Abstract

The morpho-anatomical, photosynthetic and transpiration features of 1, 2, 3-year-old needles of the Pinussibirica Du Tour grafting were studied. Cuttings were taken from donor trees of different ontogenetic ages (juvenile,3–5 years; immature, 20–60 years; generative, 200–350 years and senile, 350–700 years) and grafted onto 5-year-old P.sibirica stocks. The maximum values of the length, needles cross-sectional area and the photosynthesis were identifiedfor two-year and three-year needles of senile grafts, generative and juvenile grafts were characterized by intermediatevalues of these parameters. The differences between the ontogenetic groups decreased in the current year needles. Thetranspiration rate decreased with the needles aging, but did not differ between ontogenetic groups.