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Title: Seed Cryopreservation, Germination, and Micropropagation of Eastern Turkeybeard, Xerophyllum asphodeloides (L.) Nutt.: A Threatened Species from the Southeastern United States
Xerophyllum asphodeloides (Xerophyllaceae), known as eastern turkeybeard, is an herbaceous perennial found in eastern North America. Due to decline and destruction of its habitat, several states rank X. asphodeloides as “Imperiled” to “Critically Imperiled”. Protocols for seed cryopreservation, in vitro germination, sustainable shoot micropropagation, shoot establishment in soil, and seed germination are presented. Seeds from two tested sources were viable after 20 months of cryopreservation. Germination of isolated embryos in vitro was necessary to overcome strong seed dormancy. Shoot multiplication and elongation occurred on ½ MS medium without PGRs. Shoots rooted in vitro without PGRs or with 0.5 mg/L NAA or after NAA rooting powder treatment and placement in potting mix. When planted in wet, peaty soil mixes, shoots grew for two months and then declined. When planted in a drier planting mix containing aged bark, most plants continued growth. In the field, plant survival was 73% after three growing seasons. Safeguarding this species both ex situ and in situ is possible and offers a successful approach to conservation. Whole seeds germinated after double dormancy was overcome by incubation under warm moist conditions for 12 weeks followed by 12 weeks cold at 4 °C and then warm.  more » « less
Award ID(s):
1655732
NSF-PAR ID:
10295889
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Plants
Volume:
10
Issue:
7
ISSN:
2223-7747
Page Range / eLocation ID:
1462
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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