Use of molecular markers to study the genetic diversity, origin, and silviculturally valuable traits of forest stands (populations), the seed orchard stock, and the reproductive material of the Latvia’s major forest tree species (recommendations for forest regeneration and tree breeding)

Forest Development fund agreements No. 250308/S51 un 180909/S105

Study activities

1. Development of molecular marker fingerprinting protocols for pine seed plantations to identify seed batches for the control of reproductive material.
2. Genotyping of Scots pine and Norway spruce seed plantations to determine genetic diversity and structure within pine breeding material.
3. Resistance of pine populations to root rot:
   a. Assessment of Heterobasidion annosum infection levels in forest stands and individual pine trees.
   b. Determination of candidate gene expression levels in pine trees inoculated with H. annosum.
   c. Perform analysis of candidate gene copy number variations in 30 pineclones.
4. Select potential candidate genes and alternative molecular markers (incl. retrotransposons) for analysis of gene copy number and genome structure in Scots pine.

Results

1. Genotyping of Scots pine and Norway spruce seed plantations determined that the genetic diversity is similar to that found in natural stands. The obtained results can be used for clone identification and planning of breeding activities.
2. A molecular genetic method for detection of the root rot fungus Heterobasidium annosum in pine trees was developed. A collection of DNA extracted from pine trees with varying levels of infection was constructed. Pine candidate gene primers were designed and tested using real-time PCR. Methods for inoculating pine trees with H. annosum under controlled conditions were developed.