RA5 PAPER: Cryopreservation of maire tawake

Advances in cryopreservation of Syzygium maire (swamp maire, maire tawake) zygotic embryos, a critically endangered tree species endemic to New Zealand

October 2023

Van Der Walt K, Nadarajan J, Mathew L, Bettoni JC, Souza JA. 2023. Advances in cryopreservation of Syzygium maire (swamp maire, maire tawake) zygotic embryos, a critically endangered tree species endemic to New Zealand. Frontiers in Conservation Science 4.

ABSTRACT

Syzygium maire is a threatened Myrtaceae tree species endemic to New Zealand. Due to its highly recalcitrant seed, cryopreservation is the only viable long-term ex situ conservation option for this species. Our previous attempts to cryopreserve the embryonic axis (EAs) of S. maire were unsuccessful but did provide a better understanding of desiccation behavior, biochemical composition, oxidative status, and ultrastructural changes associated with desiccation in EAs.

We incorporated this knowledge with biophysical information to investigate two advanced cryopreservation technologies: a droplet vacuum infiltration vitrification (DVIV) method and a novel metal-mesh vacuum infiltration vitrification (MVIV) method using Plant Vitrification Solution 2 (PVS2) for cryopreservation of the EAs.

KEYWORDS

differential scanning calorimetry, recalcitrant, Myrtaceae, myrtle rust, plant vitrification solution 2 (PVS2), vacuum infiltration vitrification (VIV)