Somatic embryogenesis (SE) in conifers: a powerful research tool and a method to capture genetic gains from the breeding programs

Egertsdotter 1150 766

Somatic embryogenesis (SE) is an in vitro based clonal propagation method that can be used as a model system for research, or for multiplication of valuable seeds of commercial value or for conservation of threatened species.

In order to meet the demands on future forests for higher productivity and also for higher adaptability to climate change, it is necessary to capture the genetic gains from the breeding programs. This can only be done by large-scale clonal propagation of elite trees selected from the breeding programs.

For spruce and other conifers, somatic embryogenesis (SE) is the only method that has the potential for clonal propagation to sufficiently large numbers of elite trees for commercial planting.

UE ny bild3The process steps of somatic embryogenesis (SE) in conifers

Cost effective SE-plant production requires automated methods. Such methods have been demonstrated on a pilot scale for Swedish forestry operations.

In the UPSC SE lab, we have an automated instrument based on the same key technology utilized in the pilot system for SE plant production (the SE Fluidics System). The instrument is a valuable tool in fundamental research projects to study embryo development. It can perform dispersion, separation/singulation, image analysis and selection of plant propagules such as somatic embryos.

FluidicsThe R&D SE Fluidics System located in the Somatic Transformation Facility at UPSC

Our research interest is to understand and explain the different processes that regulate development of conifer embryos into early-stage plants. We utilize somatic embryogenesis as a model system to study how metabolic processes are required and regulated during embryo development. By studying the nutritional requirements of the embryo during development and the correlated active cellular processes, we have found that nitrogen utilization appears to be regulated over the course of embryo development with the earlier embryo stages benefiting from a supply of organic nitrogen such as glutamine (Dahrendorf et al. 2018). During later stages of embryo development, our results indicate the importance of desiccation tolerance and suggest key functions for different types of carbohydrates (Businge et al. 2013). Key metabolic events during shoot and root apical meristem formation are associated with morphological events during early plant formation (Dobrowolska et al. 2016).

sweden_greySvensk sammanfattning

Latest Publications

  1. Automation and Scale Up of Somatic Embryogenesis for Commercial Plant Production, With Emphasis on Conifers
  2. Improved and synchronized maturation of Norway spruce (Picea abies (L.) H.Karst.) somatic embryos in temporary immersion bioreactors
    In Vitro Cell Dev Biol Plant. 2018, 54(6):612-620
  3. Nitrogen utilization during germination of somatic embryos of Norway spruce: revealing the importance of supplied glutamine for nitrogen metabolism
    Trees 2018, 33(2):383-394
  4. Analysis of Nitrogen Utilization Capability during the Proliferation and Maturation Phases of Norway Spruce (Picea abies (L.) H.Karst.) Somatic Embryogenesis
    FORESTS 2018, 9 (6)
  5. Plant physiological and genetical aspects of the somatic embryogenesis process in conifers
    Scand. J. For. Res. 2018 
  6. Metabolome and transcriptome profiling reveal new insights into somatic embryo germination in Norway spruce (Picea abies)
    Tree Physiol. 2017; 37 (12):1752-1766
  7. Nitrogen uptake and assimilation in proliferating embryogenic cultures of Norway spruce-Investigating the specific role of glutamine
    PLoS One. 2017, 12(8):e0181785 eCollection 2017
  8. Evaluation of a New Temporary Immersion Bioreactor System for Micropropagation of Cultivars of Eucalyptus, Birch and Fir
    FORESTS 2017, 8 (6)
  9. DNA methylome of the 20-gigabase Norway spruce genome
    Proc Natl Acad Sci U S A. 2016, 113 (50):E8106-E8113
  10. Histological analysis reveals the formation of shoots rather than embryos in regenerating cultures of Eucalyptus globulus
    Plant Cell, Tissue and Organ Culture, 2017 128 (2):319-326
  11. Fraser fir somatic embryogenesis: high frequency initiation, maintenance, embryo development, germination and cryopreservation
    NEW FORESTS 2016, 47(3):453-480
  12. Bioreactor technology for clonal propagation of plants and metabolite production
    FRONTIERS IN BIOLOGY (2015) 10:177
  13. A possible biochemical basis for fructose-induced inhibition of embryo development in Norway spruce (Picea abies)
    Tree Physiol. 2014; 34(6):657-69
  14. Close to the application of somatic embryogenesis
    News and Views, Scandinavian Journal of Forest Research (2014) 29, 615-616
  15. The effect of carbohydrates and osmoticum on storage reserve accumulation and germination of Norway spruce somatic embryos
    Physiol Plant. 2013; 149(2):273-285
  16. Metabolite profiling reveals clear metabolic changes during somatic embryo development of Norway spruce (Picea abies)
    Tree Physiol. 2012 , 32(2):232-244
  17. Comparison of gene expression markers during zygotic and somatic embryogenesis in pine
    In Vitro Cell.Dev.Biol.-Plant (2012) 48:341
  18. A possible biochemical basis for fructose-induced inhibition of embryo development in Norway spruce (Picea abies)
    Tree Physiol. 2011; 31(52): 539-554
  19. Possible effect from shear stress on maturation of somatic embryos of Norway spruce (Picea abies)
    Biotechnol. Bioeng. 2011, 109 (5), 1089-99
  20. Effects from shear stress on morphology and growth of early stages of Norway spruce somatic embryos
    Biotechnol. Bioeng. 2010; 105: 588–599
  21. Identification and characterization of a matrix metalloproteinase (Pta1-MMP) expressed during Loblolly pine (Pinus taeda) seed development, germination completion, and early seedling establishment
    Planta 2009; 230(2): 339- 354
  22. Lignin biosynthesis in transgenic Norway spruce plants harboring antisense constructs of cinnamoyl CoA reductase (CCR)
    Transgenic Res. 2008, 17: 379 
  23. Effect of fluid shear stress on endocytosis of heparan sulphate and low density lipoproteins
    J. Biomed. Biotechn. 2007, Article ID 65136, 8 pages,