Perennial Life Style of Populus: Dormancy Cycling and Overwintering

Abstract

Deciduous trees in boreal and temperate areas are strictly conditioned by the environment, especially by photoperiod and temperature. However, it is in particular the successful submission to these conditions that has rewarded them with long-life spans. A crucial strategy to ensure growth over many seasons is to timely assume dormancy and a level of hardiness that permits survival through winter. A consensus is emerging that dormancy, although traditionally regarded as a systemic feature, is a property of the shoot apical meristem (SAM). This chapter discusses our current understanding of the regulatory mechanisms that drive the annual cycles of dormancy and acclimation.