Operational breeding of birch

Work package 1 aims to develop speed breeding for birch and to achieve this goal several parts need to be developed. In project 1 methods for early flower induction will be developed and implemented. In project 2 we will develop resources necessary for genomic selection, such as field trials, and other methods to make the breeding more efficient. In project 3 we will develop the genomics tools necessary for implementing genomic selection. 

The overall goal of the project is to carry operational breeding of silver birch, and support applied research concerning birch breeding to increase stand productivity and quality properties of individual trees. The goal will be realized by a development of genomic selection tools and an establishment of first genomic populations of silver birch. 

A well-functioning operational breeding program is a prerequisite for the development and practical implementation of more advanced methods and techniques to forest tree breeding. The ongoing breeding programme for silver birch has been based on a conventional breeding with testing of identified plus-trees and consecutive selection of superior genotypes to breeding populations. With rather small investments compared with coniferous species, growth and quality of silver birch has been significantly improved.   

Constantly developing genotyping techniques and decreasing genotyping costs allows testing and further implementation of new breeding strategies and tools as genomic selection. Silver birch is a good candidate for implementation of genomic selection as it has favourable flowering abilities i.e., it is flowering relatively early and has been found to be prone for flowering induction.  

This part of work package 1 will be divided into two parts: operational breeding - genomic selection (OB – GS) and operational breeding - conventional breeding (OB - CB).

The OB – GS will concern research and development of tools that will allow an implementation of genomic selection into silver birch breeding program. Activities in the OB – GS depends on a development of SNP-chip in the Phd2 that will be used further for genotyping of existing clonal field trials. The success of implementation will be dependent on possibilities to induce flowering for a wide range of genotypes in the populations. The methods for flowering induction will be developed in Phd1.  

In the second part of this project (OB-CB), we will continue a conventional breeding programme for silver birch, that have been initiated in the end of 1980’s. The program has tested ca. 1300 plus-trees that were tested. Out of them, seven breeding populations have been selected and create a base for further development. Populations are distributed over a latitudinal gradient in the country. The current testing strategy is a progeny test with forward selection of best individuals within the families.  

At the end of the project, we will be able to quantify the costs, benefits, and risks of transition from conventional breeding to breeding dependent on genomic selection. Such analysis will give a background for taking a decision of transition from conventional breeding to quick breeding with a use of genomic selection methods.

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