Siberian Federal University

Issue

Journal of Siberian Federal University. Biology. 2018 11 (3)

Authors

Morozova, Tatyana I.; Voronin, Viktor I.

Contact information

Morozova, Tatyana I.: Siberian Institute of Plant Physiology and Biochemistry SB RAS 123 Lermontov Str., Irkutsk, 664033, Russia

Keywords

Siberian larch; defoliation; radial and brachiblasts increment

Abstract

We propose a method for dating of growth seasons of Siberian larch (Larix sibirica Ledeb.) following insect infestation events and defoliation. Needle damage during the growth phase triggers tree investment into additional growth of brachyblasts within the same season. Dissecting brachyblasts allows the identification of these secondary growth events. We tested this method in the Baikal region, East Siberia, in larch forest sites infested by the gypsy moth (Lymantria dispar L.) from 1997 to 2000. Defoliation of trees due to the infestation was highest in 1997 (63%) and decreased gradually to 46% in 1998, 50% in 1999 and 35% in 2000. During the period of the Lymantria dispar outbreak some brachyblasts had needles reduced by four times after defoliation. The proposed method allows retrospective identification of years of larch canopy damage and defoliation not only by insects, but also fungi or toxic gases in the case of early summer and summer defoliation. Wintering buds are already formed during this period, so defoliation and elimination of its inhibiting impact (power) on the growth of wintering buds results in their fast regeneration

Pages

275-284

Paper at repository of SibFU

https://elib.sfu-kras.ru/handle/2311/71055

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License (CC BY-NC 4.0).