Ageing of trees: application of general ageing theories.

The main questions posed in ageing theories are how ageing evolved and whether or not it is programmed. While these questions have not yet been clearly resolved, several groups of possible theories have been published on this topic. However, most of these theories do not consider plants, and the specific traits involved in their ageing mechanisms. The first trait covers clonality and sectoriality and the second concerns the lack of a differentiated germ line. The lack of a germ line prevents telomere shortening which can lead to the transfer of somatic mutations into sexual offspring, while sectoriality in trees causes isolation of potentially catastrophic events in one tree part, thus creating a population of more or less independent modules within one axis. The processes of population dynamics, including ageing, can act within the framework of an individual tree as well as in that of the population as a whole, although the processes involved differ and consequently result in different effects.