Developing cryopreservation for Picea sitchensis (Sitka spruce) somatic embryos:: A comparison of vitrification protocols

Two vitrification-based cryopreservation protocols, encapsulation/dehydration and PVS2 were applied to Stage 2 (globular) and Stage 4 (torpedo) somatic embryos (SE) from Picea sitchensis. Two recovery responses: partially differentiated embryogenic suspensor masses (ESM) and dedifferentiated non-embryogenic masses (NEM) were observed following exposure to LN. All genotypes tested, proliferated NEM, similar to 10 to 100% of the total SE cryopreserved. A General Linear Model applied to NEM recovery data demonstrated several different factors (developmental state and genotype, treatment, culture age) interacted at a significant level (P<0.05) to influence proliferation. One genotype was capable of proliferating ESM after cryopreservation using encapsulation/dehydration, this response was achieved for Stage 4 embryos derived from the youngest ESM tissue.