Abstract:
The combined approaches between ex situ and in situ conservation are of great importance for threatened species in urgent need of protection. This study aims to develop concrete actions to preserve the relic of 30 adult trees of the Sicilian fir (Abies nebrodensis) from extinction using long-term germplasm conservation in liquid nitrogen (LN, -196 °C). Pollen grains were collected, and their moisture content (MC) was measured. Then, viability (2,3,5-tryphenyl tetrazolium chloride, TTC), in vitro germinability, and enzymatic antioxidant activity (ascorbate peroxidase, APX; catalase, CAT) were evaluated before and after cryopreservation. Seeds collected from mature cones underwent X-ray analysis, and only full seeds were used to excise the zygotic embryos (ZEs) for cryopreservation. The MC percentage of ZEs was determined, and then they were plunged in LN with (+PVS2) or without (-PVS2) Plant Vitrification Solution 2; untreated ZEs were used as a control. Viability (TTC test) and in vitro germination were assessed for all ZEs (+PVS2, -PVS2, and control). Embryogenic callus (EC) lines obtained from mature ZEs were cryopreserved applying the \'encapsulation-dehydration\' technique. This study has allowed, after optimizing cryopreservation protocols for pollen, ZEs, and EC of A. nebrodensis, to establish the first cryobank of this endangered species in Polizzi Generosa (Palermo, Italy), inside the \'Madonie Regional Park\'. The strategy developed for Sicilian fir conservation will pave the way for similar initiatives for other critically endangered conifer species.
摘要:
异位和就地保护之间的结合方法对于迫切需要保护的受威胁物种非常重要。这项研究旨在采取具体行动,使用液氮中的长期种质保护(LN,-196°C)。收集了花粉颗粒,并测量了它们的水分含量(MC)。然后,生存力(氯化2,3,5-三苯基四唑,TTC),体外发芽,和酶促抗氧化活性(抗坏血酸过氧化物酶,APX;过氧化氢酶,CAT)在冷冻保存之前和之后进行评估。从成熟的视锥细胞中收集的种子进行了X射线分析,并且仅使用完整的种子切除合子胚(ZE)进行冷冻保存。确定了ZE的MC百分比,然后将它们投入具有(+PVS2)或不具有(-PVS2)植物玻璃化溶液2的LN中;使用未处理的ZE作为对照。评估所有ZE(+PVS2、-PVS2和对照)的活力(TTC测试)和体外萌发。应用“封装-脱水”技术将从成熟的ZE获得的胚性愈伤组织(EC)系冷冻保存。这项研究允许,在优化花粉冷冻保存方案后,ZEs,和A.nebrodensis的EC,在PolizziGenerosa(巴勒莫,意大利),在“玛多尼地区公园”内。为西西里冷杉保护制定的战略将为其他极度濒危针叶树物种的类似举措铺平道路。