The breeding of forest trees is only a few decades old, and is a much more complicated, longer, and expensive endeavor than the breeding of agricultural crops. One breeding cycle for forest trees can take 20–30 years. Recent advances in genomics and molecular biology have revolutionized traditional plant breeding based on visual phenotype assessment: the development of different types of molecular markers has made genotype selection possible. Marker-assisted breeding can significantly accelerate the breeding process, but this method has not been shown to be effective for selection of complex traits on forest trees. This new method of genomic selection is based on the analysis of all effects of quantitative trait loci (QTLs) using a large number of molecular markers distributed throughout the genome, which makes it possible to assess the genomic estimated breeding value (GEBV) of an individual. This approach is expected to be much more efficient for forest tree improvement than traditional breeding. Here, we review the current state of the art in the application of genomic selection in forest tree breeding and discuss different methods of genotyping and phenotyping. We also compare the accuracies of genomic prediction models and highlight the importance of a prior cost-benefit analysis before implementing genomic selection. Perspectives for the further development of this approach in forest breeding are also discussed: expanding the range of species and the list of valuable traits, the application of high-throughput phenotyping methods, and the possibility of using epigenetic variance to improve of forest trees.

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Raspberry is a valuable berry crop containing a large amount of antioxidants that correlates with the color of the berries. We evaluated the genetic diversity of differently colored raspberry cultivars by the microsatellite markers developed using the flavonoid biosynthesis structural and regulatory genes. Among nine tested markers, seven were polymorphic. In total, 26 alleles were found at seven loci in 19 red (Rubus idaeus L.) and two black (R. occidentalis L.) raspberry cultivars. The most polymorphic marker was RiMY01 located in the MYB10 transcription factor intron region. Its polymorphic information content (PIC) equalled 0.82. The RiG001 marker that previously failed to amplify in blackberry also failed in black raspberry. The raspberry cultivar clustering in the UPGMA dendrogram was unrelated to geographical and genetic origin, but significantly correlated with the color of berries. The black raspberry cultivars had a higher homozygosity and clustered separately from other cultivars, while at the same time they differed from each other. In addition, some of the raspberry cultivars with a yellow-orange color of berries formed a separate cluster. This suggests that there may be not a single genetic mechanism for the formation of yellow-orange berries. The data obtained can be used prospectively in future breeding programs to improve the nutritional qualities of raspberry fruits.