Improvement: enhancing quality and quantity


Forest reproductive material can be improved in many ways - physically, physiologically, genetically and quantitatively. In this section we are concerned with improving both genetic quality and quantity of seeds produced. The physical, physiological and phytosanitary qualities of seeds were mentioned in the topic onHandling and analyzing material.Any programme of genetic improvement must be built on the correct choice of species and its provenance. Efforts to improve genetic quality of the wrong species and/or poor provenances will be wasted. This has been covered in the page onSelecting species and sources. In its broadest sense, there are three main aspects to the topic of improvement, which are summarised in the table below (which applies to genetic resources in general):
  • First, there is the requirement to conserve (protect) genetic variation, and avoid its degradation or loss.
  • Second, we can actively improve genetic quality by selection and breeding within our chosen species, provenances, and stands.
  • Third, there is a need to ensure that the genetic material is reproduced in sufficient quantities for planting needs.


MANAGEMENT OF GENETIC RESOURCES
OF FOREST TREES AND SHRUBS:
CONCEPTS AND COMPONENTS
 (from Palmberg-Lerche, C.)
WHAT?
HOW?
WHERE?




CONSERVATION


In situ conservation
Protected Areas
Natural forests managed for
productive or protective purposes
Plantations, planted trees
(only occasionally applicable)


Ex situ conservation
Plantations, planted trees
Breeding populations, clone banks,
ex situ conservation stands
Seed, Pollen, in vitro cultures




ENHANCEMENT


Selection
Natural forests managed for
productive or protective purposes
(Through silvicultural interventions)
Plantations, planted trees
Breeding populations
Breeding programmes

Improvement and breeding
Plantations, planted trees
Breeding populations,
breeding programmes

SUSTAINABLE UTILISATION

Sustainable forest management
Natural forest managed for
productive or protective purposes
Plantations, planted trees
Protected Areas
(only occasionally applicable)

We provide an overview of the key issues and sources of information for these aspects under three groups of activities: (1) the conservation of desirable species and provenances to make sure they continue to be available; (2) the active process of improving the genetic quality of the material by selection and breeding, and (3) techniques to ensure that quantity of the desired material is maintained.

  • Conserving desirable sources
  • Improving genetic quality
  • Sustaining production
last updated:  Tuesday, April 17, 2007