Viability of ‘ōhai Sesbania tomentosa seeds after 3 decades of ambient conditions
The plant species Sesbania tomentosa (‘ōhai; Fabaceae) is endemic to the Hawaiian Islands, federally listed as endangered in the USA and has been proposed for categorization as Vulnerable on the IUCN Red List. In 2021, c. 12,000 seeds from 12 seed lots collected during 1990–1992 from across the Hawa...
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| Format: | Article |
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Cambridge University Press
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| Online Access: | https://www.cambridge.org/core/product/identifier/S0030605323001461/type/journal_article |
| _version_ | 1797404858358169600 |
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| author | Emily Saling Dustin Wolkis |
| author_facet | Emily Saling Dustin Wolkis |
| author_sort | Emily Saling |
| collection | DOAJ |
| description | The plant species Sesbania tomentosa (‘ōhai; Fabaceae) is endemic to the Hawaiian Islands, federally listed as endangered in the USA and has been proposed for categorization as Vulnerable on the IUCN Red List. In 2021, c. 12,000 seeds from 12 seed lots collected during 1990–1992 from across the Hawaiian Islands were discovered in ambient herbarium conditions (55% relative humidity (RH) at 20 °C). International gene bank standards suggest drying seeds in equilibrium with 15% RH and stored at −18 °C. To investigate seed viability, we mechanically scarified then sowed 15 seeds from each accession at daily alternating regimes of 12 h light and 12 h dark at temperatures of 25/15 °C, respectively. Germination was observed after 7 days and ended after 34 days. Mean final germination was 88.9 ± SD 0.1% (range 73–100%). Each seed lot was accessioned into the National Tropical Botanical Garden's Seed Bank and Laboratory. In seeds with a water-impermeable seed coat (i.e. physical dormancy), such as S. tomentosa, seeds can desorb but not absorb water. Therefore, if the seeds were initially dried, although exposed to high RH for up to 32 years, seed equilibrium RH may have remained low, which may in part explain the observed high germinability. This study holds significance for managers who are working to conserve this endangered Hawaiian species and suggests that even suboptimal conditions may still yield highly viable seeds several decades into the future. |
| first_indexed | 2024-03-09T03:02:10Z |
| format | Article |
| id | doaj.art-9bde04819b5749cf8c332af52743959f |
| institution | Directory Open Access Journal |
| issn | 0030-6053 1365-3008 |
| language | English |
| last_indexed | 2024-03-09T03:02:10Z |
| publisher | Cambridge University Press |
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| series | Oryx |
| spelling | doaj.art-9bde04819b5749cf8c332af52743959f2023-12-04T13:13:29ZengCambridge University PressOryx0030-60531365-30081410.1017/S0030605323001461Viability of ‘ōhai Sesbania tomentosa seeds after 3 decades of ambient conditionsEmily Saling0https://orcid.org/0009-0002-5498-3041Dustin Wolkis1https://orcid.org/0000-0002-8683-5855Department of Science and Conservation, National Tropical Botanical Garden, Kalāheo, Hawai‘i, USADepartment of Science and Conservation, National Tropical Botanical Garden, Kalāheo, Hawai‘i, USA IUCN Species Survival Commission Seed Conservation Specialist GroupThe plant species Sesbania tomentosa (‘ōhai; Fabaceae) is endemic to the Hawaiian Islands, federally listed as endangered in the USA and has been proposed for categorization as Vulnerable on the IUCN Red List. In 2021, c. 12,000 seeds from 12 seed lots collected during 1990–1992 from across the Hawaiian Islands were discovered in ambient herbarium conditions (55% relative humidity (RH) at 20 °C). International gene bank standards suggest drying seeds in equilibrium with 15% RH and stored at −18 °C. To investigate seed viability, we mechanically scarified then sowed 15 seeds from each accession at daily alternating regimes of 12 h light and 12 h dark at temperatures of 25/15 °C, respectively. Germination was observed after 7 days and ended after 34 days. Mean final germination was 88.9 ± SD 0.1% (range 73–100%). Each seed lot was accessioned into the National Tropical Botanical Garden's Seed Bank and Laboratory. In seeds with a water-impermeable seed coat (i.e. physical dormancy), such as S. tomentosa, seeds can desorb but not absorb water. Therefore, if the seeds were initially dried, although exposed to high RH for up to 32 years, seed equilibrium RH may have remained low, which may in part explain the observed high germinability. This study holds significance for managers who are working to conserve this endangered Hawaiian species and suggests that even suboptimal conditions may still yield highly viable seeds several decades into the future.https://www.cambridge.org/core/product/identifier/S0030605323001461/type/journal_articleDesiccationex situ plant conservationherbariumphysical dormancyseed bankingseed longevitySesbania tomentosawater-impermeable seed coat |
| spellingShingle | Emily Saling Dustin Wolkis Viability of ‘ōhai Sesbania tomentosa seeds after 3 decades of ambient conditions Oryx Desiccation ex situ plant conservation herbarium physical dormancy seed banking seed longevity Sesbania tomentosa water-impermeable seed coat |
| title | Viability of ‘ōhai Sesbania tomentosa seeds after 3 decades of ambient conditions |
| title_full | Viability of ‘ōhai Sesbania tomentosa seeds after 3 decades of ambient conditions |
| title_fullStr | Viability of ‘ōhai Sesbania tomentosa seeds after 3 decades of ambient conditions |
| title_full_unstemmed | Viability of ‘ōhai Sesbania tomentosa seeds after 3 decades of ambient conditions |
| title_short | Viability of ‘ōhai Sesbania tomentosa seeds after 3 decades of ambient conditions |
| title_sort | viability of ohai sesbania tomentosa seeds after 3 decades of ambient conditions |
| topic | Desiccation ex situ plant conservation herbarium physical dormancy seed banking seed longevity Sesbania tomentosa water-impermeable seed coat |
| url | https://www.cambridge.org/core/product/identifier/S0030605323001461/type/journal_article |
| work_keys_str_mv | AT emilysaling viabilityofohaisesbaniatomentosaseedsafter3decadesofambientconditions AT dustinwolkis viabilityofohaisesbaniatomentosaseedsafter3decadesofambientconditions |