2018 National Meeting

Ed Guerrant, Rae Selling Berry Seed Bank

Penstemon peckii (G3-S3 Federal SOC) is an Oregon endemic with a relatively compact range in the semi-arid Ponderosa pine forest east of the Cascade Mountains. The vast majority of known populations (ca 93%) are almost entirely within the Sisters Ranger District of the Deschutes National Forest. A 1992 Species Conservation Strategy by Cindi O’Neil found that it is “Best adapted to open full sun habitats, low vegetative competition and natural fire.” The natural fire frequency was 7 to 15 years, but active fire suppression for many decades had diminished and degraded habitat. Number one in the “What we do not know” list is “How long does Peck’s penstemon seed remain viable in the soil seed bank?” To address that question, in 1992 we gathered seeds from multiple populations across the species’ range. We mixed seeds from 11 populations into a single, large bulk sample in order to compare their survivorship in the soil seed bank and in an ex situ seed bank. In addition to initial trials of fresh and dried and frozen seeds, samples have been removed from the field and ex situ seed bank after 6, 12, 18 months, and then at 4, 15 and now 25 years. The current round of germination trials of 25-year old seeds is still underway, but to date, approximately 26% of those stored in the soil and 51% in the freezer have germinated. The species clearly has the capacity to form a long-lived soil seed bank.

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Friday, May 4, 2018

Anita Tiller and Suzzanne Chapman, Mercer Botanic Gardens

Mercer Botanic Gardens, a Harris County(HC) Precinct 4(P4) Parks facility is susceptible to periodic floods. Rainfall in the drainage basin of Cypress Creek, adjacent to Mercer, ranged from 35-50” during the course of Hurricane Harvey in August 2017. As a participating institution for the CPC, Mercer maintains a seed bank, conservation nursery, display garden and a prairie preserve. The Mercer Botanical Center (MBC), Mercer’s research facility received 8-9” of flood water. The seed bank within the MBC received no damage since collections remained above flood water and no power was lost due to the building’s standby generator. Mercer’s CPC nursery received over 10’ of flood water. Even though plant stock remained under water for about 5 days, the collections suffered minimal damage. Mercer’s endangered species display garden received about 8’ of flood water for about 5 days. Some display plants were lost and others are recovering. Mercer's conservation staff have much experience with preventative disaster maintenance strategies, thus conservation collections suffered minimal loss due to our maintenance protocols and diligent post flood cleanup. Fall 2017 surveys and seed collections were completed at the HC P4 Prairie Dawn Preserve. April 2018 surveys at the preserve of Hymenoxys texana found about 1,000 more plants than the 60 surveyed in 2016, though more than 10,000 less prior to the April and Tax Day floods of 2016. Immediate support received from HC P4 personnel, Mercer volunteers and from partners and donors, including the CPC, greatly assisted Mercer’s recovery.

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Friday, May 4, 2018

Peter Zale and Matt Taylor, Longwood Gardens

Several species of Spiranthes native to the Eastern U.S. are considered rare, threatened or endangered by federal and state agencies. Using the Pennsylvania endangered Spiranthes casei as a model species, experiments were designed to determine optimal conditions for in vitro seed germination and seedling development. Seeds were collected in November 2015 from 10 individual plants found in three subpopulations in Elk and McKean counties, Pennsylvania, and air-dried for six weeks. Seeds were surface sterilized for 10 or three minutes in a 10% bleach solution, then plated onto a commercially available terrestrial orchid seed germination media: P723, M551 or K400 (Phytotechnology Labs, Shawnee Mission, KS) with 5 replicate plates. Seed germination ranged from 24 to 60 % and occurred on all three media only with the 3-minute treatment. None of the seeds treated with bleach for 10-minutes germinated and visual inspection revealed badly damaged embryos. After shoot initiation, 150 seedlings were transferred to individual test tubes on one of two media (P723 or P658) and each was given one of the three 24-hour light/dark photoperiod treatments for 10 months: 24/0, 18/6, or 0/24. Seedling survival and growth occurred in all treatments, but seedlings on P723 with the 24/0 or 16/8 photoperiod treatments had a significantly greater fresh weight, leaf length, number of roots and root length than light treatments on P658 and dark treatments. Results indicate Spiranthes seeds can be damaged by extended chemical scarification times and the light is essential for optimal seedling growth.

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Friday, May 4, 2018

Chris Walters, Research Leader of the Plant Germplasm Preservation Research team at USDA-ARS National Laboratory for Genetic Resources Preservation

Knowing how long storedgermplasmsurvives is critical for effective banking of genetic resources. Longevity is inherently difficult to predict because there are so many factors controlling how cells respond to storage conditions. Uncertainty increases forgermplasmcollections of natural populations, especially rare species that might have additional issues with the reproductive biology or with assessments ofviabilityor aging. Storage conditions invariably involve manipulation of temperature and moisture, and this presentation will describe some of the basics of why this leads to long-term preservation of somegermplasmand what we think is going wrong when the desired longevity is not achieved. Preserving germplasm involves slowing down the rate that ‘clocks tick,’ and this means that we need to slow down the rate that molecules move. The most effective way to do this is by having molecules impede their own movement by pushing them together tightly and forming a solid (like a traffic jam). This process begins during development when cells accumulate dry matter to replace water, allowing molecules to come into close proximity naturally without deforming stresses. Cells from orthodox seeds shrink a little and solidify during maturation drying, but major mechanical stresses are easily avoided. Once in the solid, the rules for molecular movement are mostly dominated by how tightly the molecules are packed (determined by properties of the molecules and concentration of water) and by how much energy they have (determined by temperature). Given a particular molecular configuration in solidified cytoplasm, the effect of lowering temperature on mobility is predictable, as is the kinetics of reactions, such as aging, that are regulated by mobility. Lowering temperature slows down aging reactions in the same way in diverse seeds and spores; thus, reducing storage temperature from 25 to -18oC will usually increase longevity about 30 fold (if moisture is optimized). The good news is thatgermplasmthat survives 4 years at 25oC will survive about 120 years in the freezer. The bad news is thatgermplasmthat survives only 40 days at 25oC won’t survive much longer than 3 years in the freezer. Freezer temperatures appear to be a nexus for how molecules move in biological systems. Below -18oC, aging reactions appear to be driven by molecules vibrating, which has a low temperature dependency. Thus, a large temperature decrease gives only moderate benefits. Currently, we estimate a 3 to 5 fold increase in longevity by storinggermplasmcryogenically rather than in the freezer. Further complexity in structure and mobility of solidifiedgermplasmis introduced by the presence of oil droplets in the cytoplasm. We have linked lipid crystallization with faster aging in the freezer and explain this as the condensed structure of solidified lipids causing greater pore space, hence increased mobility, in aqueous domains of the cytoplasm. Collectively our work provides a theoretical framework to explain why lowering temperature and moisture affect longevity and to predict how longgermplasmstored at -18C will survive.

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Thursday, May 3, 2018

Jennifer Neale, Denver Botanic Gardens

As scientific programs at Denver Botanic Gardens continue to grow we are working to standardize data collection across all projects to enhance and improve data utility. We have developed uniform protocols for documenting biodiversity for all studies whether they regard demographic studies, ecological monitoring, seed conservation, or floristic surveys. Collection of specimens and associated tissue samples has been incorporated into all studies, along with a methodical approach for tracking field photography, to ensure robustness, consistency, and cross-application of data. With the implementation of these new protocols we are readily able to share data with larger platforms such as the Global Genome Biodiversity Network (GGBN), Integrated Digitized Biocollections (iDigBio), and the Global Biodiversity Information Facility (GBIF).

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Friday, May 4, 2018

Cheryl Birker, Seed Conservation Program Manager and Evan Meyer, Rancho Santa Ana Botanic Garden

Abies bracteata(Bristlecone fir; Santa Lucia fir) is a 12-30 meter tall tree restricted to a small, wildfire prone range in the Santa Lucia Mountains on the central coast of California. While several botanical gardens maintain living specimens, it remains rare in cultivation and until this project, seeds had yet to be conserved in agermplasmrepository for long-term conservation. In 2014 Rancho Santa Ana Botanic Garden (RSABG) partnered with the United States Forest Service to seed bankAbies bracteata, but a number of complications postponed the collection, including low cone production, high seed predation, and cone inaccessibility. The populations have been impacted by years of drought as well as by the 2016 Soberanes fire, which also impeded collecting efforts. In 2017, a maternal-line conservation seed collection was made with the help of a tree climber and some unconventional collecting techniques. Seeds are now stored in the RSABG seed bank, with a backup collection at the National Laboratory for Genetic Resources Preservation and a living collection in production in the RSABG nursery facility. The lessons learned during this collecting effort will help inform future collections ofAbies bracteatafrom additional populations throughout its range.

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Thursday, May 3, 2018

Jennifer Ceska,Jenny Cruse Sanders, Jim Affolter, Heather Alley, Linda Chafin and Emily Coffey,The State Botanical Garden of Georgia

A tall and elegant wildflower, Smooth Coneflower was dwindling to extinction on Georgia’s roadsides where seed heads and whole plants were poached or killed by roadside maintenance. With her Master’s thesis demonstrating that endangered plants could be grown from seeds and successfully replanted in safeguarding sites, SBG’s Heather Alley changed the way Smooth Coneflower conservation was carried out in Georgia. SBG has grown more than 1,000 Smooth Coneflower plants since 2000. We have planted 900 Smooth Coneflower plants and sown 3,700 seeds directly into the wild. We work with the GPCA and our volunteers to annually monitor and manage four Smooth Coneflower sites in the wild.

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Friday, May 4, 2018

Jordan Wood, Jeremie Fant, Andrea Kramer and Kay Havens, Chicago Botanic Garden

Genetics becomes important whenever populations become small (<100). This includes loss o fgenetic diversity from drift, increased expression of deleterious genes due to inbreeding, and limiting local adaptation. Since many species of plants are able to be seed banked, it is possible to maintain numbers well above these critical genetic thresholds. However for exceptional species, which can only be maintained as living plants, or for critically endangered species where remaining individuals are already below these numbers, the need to consider the remaining genetic diversity becomes critical. Importantly, the management focus shifts from saving a population to preserving each genetically unique individual. When you have such small numbers, it is critical to know how each individual contributes to the overall genetic diversity remaining. We are working with National Tropical Botanic Gardens (Hawaiʻi) to develop a multi-institution species management and breeding plan for Ālula(Brighamia insignis)that will ultimately support its restoration to the wild. To do this we are working with scientists at the Chicago Zoological Society to modify management software that incorporates genetics and demography information to maintain the long-term health of their captive populations of animals over the long term. Through this case study, we hope to develop collections management practices for plants that preserve important genetic diversity while identifying genetically appropriate individuals to using in crosses and that can ultimately be used to create resilient populations that can be used in reintroductions.

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Friday, May 4, 2018

Kristin E. Haskins and Sheila Murray (The Arboretum at Flagstaff), and Andrea Hazelton (Desert Butte Botany)

Acquisition of a long-term dataset is truly rare and can represent decades of hard work and thousands of dollars or more in exhausted resources. The standard model of monitoring year after year is unsustainable for most organizations and begs the question, when should it stop? The Arboretum at Flagstaff has a demography data set for Arizona cliffrose (Purshia subintegra) that has been on-going since 1996. Different ‘levels’ of monitoring have occurred over the years depending on available resources. With some recent funds, we set out to address the following questions with long-term data: 1) What is the long-term viability of the population? 2) Which life stages are most important to capture in the monitoring? And 3) can we monitor less often and still capture important life history events? Challenges included determining starting population sizes for population matrix models and gaps in data. Using the 22 years of monitoring data combined with data from published papers, anecdotes, and historic weather data, we produced population growth rates for P. subintegra and identified key life stages correlated with precipitation events, thus enabling implementation of a modified monitoring protocol, which will conserve valuable resources.

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Friday, May 4, 2018