Hardstaff Lyndle K, Funnekotter Bryn, Sommerville Karen D, Offord Catherine A, Mancera Ricardo L
Curtin Medical School, Curtin University, GPO Box U1987, Perth, WA 6845, Australia.
The Australian PlantBank, Botanic Gardens of Sydney, Mount Annan, NSW 2567, Australia.
Plants (Basel). 2025 Feb 24;14(5):699. doi: 10.3390/plants14050699.
(G.Don) Benth. (Myrtaceae) is a critically endangered rainforest species from the east coast of Australia, where populations have severely and rapidly declined due to the effects of repeated myrtle rust infection. With very limited material available in the wild and freezing-sensitive seeds that have prevented storage in a seed bank, ex situ conservation of this exceptional species has proven difficult. Material from a seed orchard grown at the Australian Botanic Garden Mount Annan was successfully used to initiate three new accessions into tissue culture from cuttings, and to undertake cryopreservation experiments using a droplet-vitrification (DV) protocol for both seeds and cultured shoot tips. Use of seedling material for tissue culture initiation was very effective, with a 94-100% success rate for semi-hardwood explants and a 50-62% success rate for softwood explants. Although no survival of seeds after cryopreservation was observed, seeds of showed some tolerance of desiccation and exposure to cryoprotective agents. Regeneration after cryopreservation using a DV protocol was demonstrated in only one shoot tip precultured on basal medium containing 0.4 M sucrose and incubated in PVS2 for 20 min prior to immersion in liquid nitrogen. These results demonstrate the value of living collections in botanic gardens for conservation research, highlight the importance of germplasm choice for tissue culture initiation, and demonstrate the potential of cryobiotechnologies for the ex situ conservation of exceptional plant species.
（G.Don）本特（桃金娘科）是一种来自澳大利亚东海岸的极度濒危雨林物种，由于反复感染桃金娘锈病，其种群数量已严重且迅速减少。由于野外可用材料非常有限，且种子对冷冻敏感，无法储存在种子库中，因此对这种特殊物种进行迁地保护已被证明很困难。从澳大利亚安南山植物园种子园获取的材料成功用于从插条开始建立三个新的组织培养种质，并使用玻璃化法（DV）对种子和培养的茎尖进行冷冻保存实验。使用幼苗材料进行组织培养启动非常有效，半硬木外植体的成功率为94 - 100%，软木外植体的成功率为50 - 62%。虽然冷冻保存后未观察到种子存活，但种子表现出一定的耐干燥性和对冷冻保护剂的耐受性。仅在一种预先在含有0.4 M蔗糖的基础培养基上预培养并在浸入液氮前在PVS2中孵育20分钟的茎尖中，证明了使用DV方案进行冷冻保存后的再生。这些结果证明了植物园活体收集在保护研究中的价值，突出了种质选择对组织培养启动的重要性，并展示了低温生物技术在特殊植物物种迁地保护中的潜力。
