Genetisk markörbaserad selektion i tallförädlingen

Results: 1.- Due to the fast advances of the high-throughput sequencing and genotyping methodologies, the original plan of genotyping only few candidate genes was extended to the much more ambitious and more powerful approach of Genorne Wide Selection (GWS). In this new approach, all the genorne (instead of few candidate genes) is analyzed for a c}ense set of random markers.

In conifers, this approach has never been applied before so the first step was to develop the kind of markers suitable to perform GWS analysis. The new markers are called complexity reduction genomic markers and are bas ed on random mutations spread in the low complexity part of the genorne (genes and intergene regions). For its development we built up a genomic library on DNA digested with restriction enzymes sensitive to methylation (do not cut the more complex part of the genorne that way getting rid off it) that way we avoided the high complexity part of the genorne which is believed to be composed ofretrotransposons (Gymny, Gypsy … ).

The development of this novel and complex methodology has consumed most of the funding. However, we think that the positive results that came out justify the effort (Whetten et al., in preparation).

Now we are designing the next step which will be to genotype the whole pedigree and search for association with growth. The growth curves were reconstructed in aparallel project also funded by Föreningen Skogsträdsförädling (ChunKao et al., 2009). Provided we will have a novel and dense set ofnovel markers, we also think that it will be also worth to make more phenotypic measurements on this pedigree.

2.-

CyanilAdenosyl di-phospate (CAD) is a gene which encodes several enzymes involved in pyrimidine biosynthesis. The products of CAD, cinnamyl alcohols, are the precursors of lignin, a major cell wall polymer of plant vascular tissues.

CAD was genotyp ed in all grandparents of the pedigree. At the same time, we studied the level of genetic variation for wood energy content in increment core samples where heating value, density, C, N and H content were estimated.

The energy content data and the growth data are being analyzed together with CAD genotypic data in order to search for association between CAD candidate gene and the phenotypic data. This method will result on the estimation of the involvement of CAD in the observed genetic variation for growth and energy content.

The parents and offsprings of the pedigree are in cue to be genotyped for CAD gene as a side project of the main application (funding will be applied for this extra project).

3.-

As a side product of this project, there has been also done an effort in comparing the low complexity genome between Scots pine and Loblolly pine. The results of such investigation are relevant in order to understand pine synteny among the most important Euroasian pine species and the most economically important pine species. The output of this research will useful as a bridge to exchange marker information among both species and therefore increasing the potential of our results.

Vision

The main output of this project has been the development of a dense set of novel genomic molecular markers. These markers will be applied in a Genome Wide analysis in the Scots pine pedigree in order to test for its potential for their implementation in the analysis of economically important traits like growth. The output of this project is leading us to a much more powerful approach than expected in the original goal, therefore, we plan to apply more funding to have the capacity for genotyping the whole pedigree for our molecular markers and also to score other phenotypic traits like diameter, wood properties and phenology.

An added value to this project is that a new statistical model has been developed by a PhD student at the Forest Genetics Research School (Hallander et al 20 l O) which will be applied to find association between the new genomic markers and the growth curve data plus to all the new phenotypic data we may be able to afford.

In synchrony with the future of the next part of this project is the sequencing of the whole spruce genome which will be carried out in UPSc. As part of the steering committee and as the major responsible of the Scots pinefNorway spruce comparative genome, I can only foresee an increasing potential of our results.

In few words, the support given by Föreningen Skogsträdsförädling to my group has been of enormous relevance in the advance of Scots pine genomic research and its application in tree breeding. As it looks now, with the new statistical and genomic tools available we are more optimistic on the applicability of modern genomic tools in the Swedish breeding program maybe as part of the new Swedish forest paradigm.