Selection and testing of conifers - Background

 

Forest Research has been involved in the selection of superior individuals within a number of species for over 40 years during which time a number of special facilities have been developed to assist the breeding process.

The job of the tree breeder is to select from the general gene pool those individuals that express superior characteristics for traits considered to be of economic value. Two things then happen to these individuals:

• The best of them are mated together to give improved planting stock (production population)
• All of them are mated according to some design (breeding population) to generate a population from which the very best are again selected.

As before, the new selections are mated together and so the process continues. The genetic gains are cumulative across generations.

What breeders are doing are selecting those trees which have an increased frequency of genes contributing towards the traits under selection.

The problem comes in trying to identify correctly those trees thought to be genetically superior. The appearance of a tree is made up of the genetic complement and the effects of the environment. Breeders have to peel away the environmental effects so that re-selection of trees can be based on measured genetic quality.