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Genetic improvement - commissioned reports


Date: 2001
Title: Genetic Improvement of Corsican Pine
Author: Steve J Lee
Full report: HTML

Summary
Novel statistical techniques more familiar in animal breeding have been used to draw together breeding value estimations of height, stem straightness and branching quality for up to 935 original plus trees planted over a range of sites between 1966 and 1987. A population of nearly 200 plus trees has been reselected. Grafted copies of the breeding population clones along with a further 68 clones selected for genetic conservation, will be planted in each of the two Corsican pine clonal archives.

The establishment of a new clonal seed orchard based on these new selections would nearly double the height gains predicted from existing clonal seed orchards whilst at the same time giving positive gains for stem straightness and branching quality. This work marks the end of the first generation of testing in the Corsican pine breeding programme.


Date: 2001
Title: Management of the Sitka Spruce Breeding and Production Populations
Author: Steve J Lee
Full report: HTML

Summary
There are currently 240 plus trees in the Sitka spruce breeding population reselected following the first cycle of selection and testing. These reselections will be involved in a programme of controlled crosses to advance the Sitka spruce breeding strategy into the next generation. The very best of the breeding population in any given generation form the production populations which generate the future planting stock. Grafted replicates are taken of all reselected trees to ensure they are not lost from either the breeding or production populations. Grafts are stored in two field-based clone banks where they are managed for the production of flowers.

Successful management of breeding and production populations is measured by the frequency of flowering, the rate at which the crossing programme is completed and continuing increases in predicted gains from family mixtures. Major improvements in efficiency are envisaged as management of grafted replicates transfers from field-based clone banks to high facility polyhouses.