Theme 1 - Forest genetics and next generation of forest trees
Theme 1 in TC4F combines the world-leading genomic research at UPSC with applied forest tree breeding and other research disciplines. Mapping of the spruce genome, studies of the relationship between genes and traits in aspen, and development of mass propagation technology are some of the tasks.
Applied forest tree breeding has been going on in an organized scale since the 1940’s. The breeders have, step by step, selected, crossed and tested trees to find individuals that combine good breeding values for growth, adaptation and quality. Genetically improved seedlings are now custom in the operational forestry. Currently, about 90 % of the Scots pine and 70 % of the Norway spruce seedlings are raised from seed harvested in seed orchards, where the improved trees are produced.
The genetic gain in the orchards currently being established amounts to approximately 20-25 %, compared with unselected trees from natural populations. However, the gain of seed orchards is always lagging behind the breeding frontier. The time from seed orchard establishment until the seeds can be harvested is long, usually 15-20 years. In the meantime, operational tree breeding has proceeded to higher genetic gains.
The breeding value of a parent tree must be tested through its offspring or copies as rooted cuttings – a field testing that takes time, and must be given time. For crops other than forest trees, but also for livestock, breeding is much quicker. It depends to some extent on shorter generation time, but also on modern biotechnology methods that provide a quicker selection process. One example is marker-aided selection that is used to identify desirable characters at an early stage.
Umeå Plant Science Centre plays a leading role in forest tree genomic research. UPSC attracted world-wide reputation when they first in the world managed to sequence the entire genome of a conifer (Norway spruce). This was the largest genome ever being sequenced. The research group has also mapped much of the genome of poplar and aspen, and are also successful in identifying relationships between genes and traits.
“Trees and Crops for the Future” contributes in Theme 1 with linking the applied forest tree breeding with modern biotechnology. The recent mapping of Norway spruce provides the foundation needed to map the entire Swedish breeding population of spruce. Genomic information on relatedness will improve the accuracy of breeding values. By using field experimental data, genetic markers can also be identified for different traits. The objective is primarily to develop tools, which would make the breeding process more efficient.
Aspen is another well-studied tree species, used as the model tree for genetic scientists. Theme 1 continues to study the relationships between genes and characters such as leaf chemistry, phenology, growth and wood properties.
When breeders along with genomic researchers develop new, valuable tree genotypes, it is also important to find efficient methods for mass propagation. Somatic embryogenesis is one of the most promising methods. Theme 1 supports research conducted at UPSC in Umeå, and has a close collaboration with another project on somatic embryogenesis in Theme 3, at SLU in Uppsala.