Tropical Forestry Handbook

Abstract

Trees compared to other organisms have a very high level of genetic diversity (Hamrick and Godt 1990). As sessile long-living plants, they need this high level of genetic variation for adaptation to highly variable environmental conditions. A set of population genetic processes such as the mating system, gene flow, selection, and migration determine the genetic composition of a tree population. First we will give an introduction and overview on the most important processes and their impact on the genetic diversity of tropical trees, and then we will go in more details for some of the processes. The genetic diversity is of fundamental function for the stability of forest ecosystems. Thus adequate measures on gene conservation are very important. We will cover this topic with a specific chapter. More recently with the advance of genomics and molecular genetics, we have a broad set of molecular markers in hand for diagnostic purposes. We highlight as one important application the use of gene markers and DNA bar coding for tree species identification and as a tool to fight against illegal logging. Finally we will give an introduction to tree breeding programs and provenance tests in the tropics.