Seeds cryopreservation of Vriesea reitzii Leme & A.F. Costa endemic bromeliad from Atlantic Rainforest

ABSTRACT Vriesea reitzii is an endemic bromeliad from the Atlantic Rainforest. The objective of this research was to evaluate the cryopreservation using the method of direct immersion of its seeds, collected from capsules at 120, 135, and 150 days after anthesis (DAA). The water content was determined before cryopreservation, while the germination percentage, germination speed index (GSI), and total soluble carbohydrates were quantified after cryopreservation. The highest percentage of moisture (17.6%) was observed in 120 DAA, while the highest percentage of germination (89.6%) and GSI (17.0) were observed in 150 DAA. Optical and transmission electron microscopy analyses were performed, and no cell damage or changes at the morpho-histological and ultrastructural levels were observed after the cryopreservation process. From these results, V. reitzii seeds can be classified as orthodox seeds and the cryopreservation (+LN) is an efficient tool for an ex situ conservation of this species.摘要 瑞氏莺歌凤梨（Vriesea reitzii）是大西洋雨林特有凤梨科植物。本研究以该物种从开花后120、135和150天（days after anthesis，缩写DAA）的蒴果中采集的种子为材料，采用直接浸没法开展超低温保存效果评估。超低温保存前测定种子含水量，超低温保存后则定量分析其发芽率、发芽速度指数（GSI）及总可溶性糖含量。其中，120 DAA的种子含水量最高，达17.6%；而150 DAA的种子发芽率（89.6%）及发芽速度指数（17.0）均为最高。通过光学显微镜与透射电子显微镜分析发现，超低温保存过程未引发细胞损伤，亦未出现形态组织学及超微结构层面的变化。综合上述结果，瑞氏莺歌凤梨（V. reitzii）的种子可归类为正统种子，超低温保存（+LN）是该物种迁地保护的有效工具。