This study develops protocols for the micropropagation and cryopreservation of Dracocephalum austriacum (Lamiaceae). It is a perennial herbaceous plant that overwinters with ground-level sprouts and is classified as critically endangered in Europe. In vitro cultures were initiated from seeds on growth-regulator-free Murashige & Skoog (MS) medium after nicking the seed coat. Propagation via shoot culture was achieved on ½ MS medium with 1 µM benzyl adenine (BAP). Rooting on various indole-3-butyric acid (IBA)-media was not reliable, but the rooting success was 80% after 10 weeks on medium with 1 µM BAP. Two starting materials underwent cryopreservation: (1) shoot tips from cold-acclimated in vitro plantlets and (2) axillary buds from winter shoots from field plants. For the cryopreservation of in vitro shoots, plant vitrification solution (PVS)3 and incubation over ice yielded the best results (~ 34% regeneration success). However, regeneration using winter acclimated buds were 100, 76 and 30% for collections in December, February and March, respectively, using the same protocol. Moreover, the ploidy levels of cryopreserved plantlets were estimated using flow cytometry. The use of winter-acclimated field material of temperate herbaceous plants or subshrubs has high potential as explant source for cryopreservation and calls for exploring this technique for other species.

这项研究开发了用于Dracocephalum austriacum的微繁殖和冷冻保存的方案（唇形科）。这是一种多年生草本植物，会随地面芽苗越冬，在欧洲被列为极度濒危物种。切开种皮后，在无生长调节剂的Murashige＆Skoog（MS）培养基上从种子开始体外培养。通过芽培养在具有1 µM苄基腺嘌呤（BAP）的1/2 MS培养基上进行繁殖。在各种吲哚-3-丁酸（IBA）培养基上生根是不可靠的，但在含1 µM BAP的培养基上10周后，生根成功率为80％。两种原始材料进行了低温保存：（1）来自冷适应的体外苗的芽尖，以及（2）来自田间植物的冬芽的腋芽。对于体外芽的冷冻保存，植物玻璃化溶液（PVS）3和冰上孵育产生了最佳结果（〜34％的再生成功）。然而，使用相同的协议，分别在12月，2月和3月使用冬季驯化的芽进行的再生分别为100％，76％和30％。此外，使用流式细胞仪评估了低温保存的苗的倍性水平。在冬季使用温带草本植物或亚灌木的田间材料具有很高的潜力，可以作为低温保存的外植来源，并呼吁对其他物种探索这种技术。