© 2001 Heron Publishing—Victoria, Canada
Desiccation, cryopreservation and water relations parameters of white spruce (Picea glauca) and interior spruce (Picea glauca × engelmannii complex) somatic embryos
Robin E. L. Percy (1), Nigel J. Livingston (2, 3), Jonathan A. Moran (2) and Patrick Von Aderkas (2)
1. B.C. Research Inc., 3650 Wesbrook Mall, Vancouver, B.C. V6S 2L2, Canada / 2. Centre for Forest Biology, Stn. CSC, University of Victoria, Victoria, B.C. V8W 3N5, Canada / 3. Author to whom correspondence should be addressed (njl@uvic.ca) / Received December 18, 2000
Summary
Effects of drying and cryopreservation on survival of spruce (Picea glauca (Moench) Voss and Picea glauca × engelmannii complex) somatic embryos (SEs) were investigated with the aim of developing simple and robust protocols for embryo storage.
Somatic embryos dried over salt solutions of known water potential (Ψ) survived removal of virtually all free water, to a
relative water content (RWC) of approximately 0.13, a value similar to that for spruce zygotic embryos from dry seed. Desiccated
SEs also survived subsequent freezing in liquid nitrogen, without the addition of cryoprotectant or pre-culture steps. Highest
survival (> 80%) after freezing in liquid nitrogen was in embryos pre-dried to Ψ of –15 to –20 MPa, which yielded RWC close
to predicted bound (apoplastic) water values. Low (< 35%) or no survival after freezing was observed in embryos pretreated
at higher Ψ (above –5 MPa) or at very low Ψ (–540 MPa, using silica gel), respectively.
Keywords:
conifers, drying, germination, growth, relative water content, somatic embryogenesis, survival, tissue culture, water potential,
water release.
