Seed Longevity Research
How Long Do Rare Seeds Live in Frozen Storage?
High rates of plant extinction have led botanical gardens to use seed banking as a cost effective conservation strategy. Thus, the CPC National Collection is maintained primarily as seeds that are stored in “orthodox” storage at -18 C in the freezers of botanical gardens. CPC’s seed banks aim to keep seeds alive for decades or centuries as safeguards against the loss of wild populations. Because most research has been conducted on crop species, no one actually knows how long many rare plant seeds can survive in seed banks.
To ensure better stewardship of rare plants, CPC’s national office, its network of botanic gardens, and the National Laboratory for Genetic Resource Preservation (NLGRP) were recently award an Institute for Museum and Library Services National Leadership Grant (MG-245983-OMS-20) to test aging and longevity in wild rare plant species seeds in a new way. Recent research with crop species shows that biochemical indicators can reliably measure seed aging and predict seed longevity. RNA integrity number (RIN) has shown particular promise as a metric of seed aging. Applying this new technology to wild species will be especially useful for curators, given the enormous variation wild seeds display in germination requirements and storage behavior.
Abronia umbellata ssp. brevifolia
Amorpha herbacea var. crenulata
Anemone patens var. multifida
Aster furcatus (Eurybia furcata)
Astragalus cremnophylax var. hevronii
Astragalus magdalenae var. peirsonii
Clarkia biloba ssp. australis
Deinandra increscens ssp. villosa
Echinocactus horizonthalonius var. nicholii
Gilia leptantha ssp. leptantha
Linum carteri var. carteri
Lupinus westianus var. aridorum
Metrosideros polymorpha var. polymorpha
Oxytropis campestris var. chartacea
Polemonium occidentale ssp. lacustre
Rhus kearneyi ssp. kearneyi
Tephrosia angustissima var. corallicola
Vaccinium crassifolium ssp. sempervirens
Goal of Study & Accession Definitions
The overarching goal of this study is to compare the germination-based viability and RNA integrity of seeds held in frozen storage for 15+ years to seed recollected or regenerated from the same plant population. We are testing the hypothesis that RNA Integrity or (RIN) can linear proxy of seed health in storage that can be used to inform curation and management decisions surrounding rare plants. Please see grant project narrative for full details.
For simplicity, hereafter, the seed currently held long term storage will be referred to as the “original accession” and seed that participants re-collect or regenerate is known as the “fresh accession.”
Species Target List & Seed Quantities
- Make one “fresh” seed collection from each target species listed in your contract. Fresh collections should either be made from the same population as the “original accessions”; from ex-situ plants of shared wild provenance; or from plants grown or bulked from seeds of a seed collection held in long term storage for 15 years or more – known as the “original accession.” The specific quantity of seed required for testing may vary depending on the size of seed and inclusion in the different experimental groups. Changes to the list of approved species or accessions recollected in the study must be approved in advance via email correspondence with CPC Contact, Dr. Katie Heineman (email@example.com)
Recollecting & Processing of “Fresh Accession”
- Participants will obtain permits necessary to collect the “fresh accession”.
- While acquiring seed for testing is a first priority, collectors should make a good faith attempt to make a full population level conservation collection according to the CPC Best Practice guidelines, meaning, in most cases, that seed not set aside for testing should be collected & stored along maternal lines.
- Clean, process, and send seeds to NLGRP within 90 days of collection to ensure that “fresh seeds” used in the study are of similar maturity.
- Send seed intended for testing in the specified quantity in a single bulk packet that integrates over available maternal lines. Participants may send the additional seed for back up storage to NLGRP simultaneously or later in the collecting season if more time is needed to process.
- All seeds collection should be processed & sent to NLGRP no later than August 31, 2023 (and no more than 90 days after your most recent seed collection).
Material Transfer of Fresh & Original Accessions to National Laboratory for Genetic Resources Preservation
- Process and send fresh seeds to NLGRP within 90 days of collection to the address below. We encourage that the “original accession” be sent in advance of the fresh collection if possible, but both should arrive at least concurrently:
- Chris Walters and Lisa Hill
1111 South Mason St.
Fort Collins, CO 80523-0001
- Chris Walters and Lisa Hill
- Email CPC staff (firstname.lastname@example.org) and Lisa Hill at NLGRP (email@example.com) prior to sending seed to ensure NLGRP is able to receive your package and to verify that an adequate quantity of seed for testing.
- Use the online NLGRP submission form on the CPC member resources section of the CPC website to submit data associated with each accession (https://saveplants.org/dashboard/resources).
- Send seed intended for testing in a single bulk packet that integrates over available maternal lines. Participants may send the additional seed for back up storage to NLGRP simultaneously or later in the collecting season if more time is needed for processing.
- Fresh and frozen sent for the first time from a CPC Participating Institution for this study will enter the NLGRP collection under the CPC-NLGRP Material Transfer Research Agreement. Details regarding this agreement can be found here.
- To release of seed for testing currently held under a Material Transfer Research Agreement at NLGRP (AKA “Research Storage” AKA MTRA), contact Lisa Hill: firstname.lastname@example.org
- To release seed for testing currently held under a Material Transfer Agreement at NLGRP (AKA “Blackbox Storage” AKA MTA), contact Stephanie Greene: Stephanie.Greene@ars.usda.gov
- Seeds should arrive at NLGRP no later than August 31, 2023 (and no more than 90 days after your most recent seed collection).
Reporting & Invoicing
- Prior to submitting your invoice for collections, collectors must ensure that:
- Both the “original” and “fresh” test packets have been received by the staff at NLGRP in Fort Collins
- Data for the fresh recollection has been entered through the NLGRP submission form on the IMLS
- You have posted one photo and one conservation update per contracted species via the CPC website at saveplants.org/dashboard
- The “conservation update” will consist a one paragraph narrative description of the recollection or seed bulking process or lessons learn through past seed curation of this species. Any photo of the species biology (flowers, fruits, habitat, field work) would be acceptable.
- Submit invoice via provided Invoice Template IMLS to email@example.com no later than September 30, 2023.
Inventory of Seeds Received by NLGRP
- This Accession Inventory Excel File contains the status of seeds received for IMLS study species as a December 22, 2021.