Preserving Plant Genomic Diversity

From Plant Press, Vol. 18, No. 3, July 2015.

By Vicki Funk
-Adapted from Natural History Unearthed

Vicki Funk (right) leads a team of collectors, including two Smithsonian undergraduate interns from the University of Delaware, Kristen Van Neste (second from left) and Sarah Gabler, for the Global Genome Initiative-Gardens project. (photo by U.S. Botanic Garden)

Did you know that half of the families of flowering plants, conifers, and ferns can be found in the Washington D.C., area? Did you know that you can see plants that are from an African desert environment, the hardened surface of a cooled Hawaiian lava flow, and a tropical rain forest, all within a few feet of each other in the nation’s capital?

It’s true and it is all free for you to enjoy right now at the U.S. Botanic Garden. We’re working with our partners at the Botanic Garden to gather a diverse array of plants. This summer marks the beginning of a collecting program called Global Genome Initiative-Gardens. It is part of the National Museum of Natural History’s Global Genome Initiative. The goal of this new collecting program is to sample the global genomic diversity of plants for preservation in the world’s biorepositories. Through partnerships with Smithsonian Gardens, the U.S. Botanic Garden and the U.S. National Arboretum, we will preserve samples of half the families of living plants around the world by the end of summer 2015.

Over the next two years, through growing partnerships with other botanical gardens, we hope to preserve samples of half the genera of living plants!

Each day, our team travels to one of the partner gardens or their production facilities and collects 20-30 plants in three ways: a pressed specimen to serve as a permanent voucher that will be stored in the museum’s U.S. National Herbarium; tissue dried in silica gel; and liquid nitrogen preserved at the Smithsonian’s biorepository at the Museum Support Center (MSC) in Suitland, Maryland.

Some recent collections from the U.S. Botanic Garden include:

Sida fallax Walp. (‘Ilima) from the hibiscus family is known only from Hawaii. This plant grows on volcanic rock and is an important colonizer, meaning that it helps establish an environment for other plants and life forms to thrive in. Its flowers are so beautiful that they are used to make Hawaiian leis and have been said to have been favored by Queen Emma.

Vicki Funk preparing the pressed specimen of Aloe rauhii Reynolds (snowflake aloe) at the U.S. Botanic Garden. (photo by Hilary-Morgan Watt)

Aloe rauhii Reynolds (snowflake aloe) is a rare succulent from Madagascar. It is a beautiful desert plant with striped leaves and coral colored flowers, and is important in the horticultural industry where it has been used to make many cultivated plants. This species—and the diverse plant life of Madagascar, more generally—is under threat and becoming increasingly hard to find. 

Theobroma cacao L. (chocolate or cacao) is a small tree native to Central and South America. While pollinated in the wild by tiny flies, the tree in the Botanic Garden is pollinated by hand. This tropical plant was long used by indigenous people throughout its range and was later exported to Europe by the Spaniards. Chocolate is now one of our favorite foods! Because of its economic importance, the whole genome of this species has been sequenced, but a voucher sample to pair with that sequence was never saved. Vouchers are important because they document what the sequenced genome actually did in life on Earth at one point in time. Genomes may be the “blueprint of Life,” but if you only save the blueprint but not the “Life,” you are clearly missing part of the story.

Asia Hall, D.C.-based high school intern enrolled in the museum’s Youth Engagement through Science Global Genome program, prepares the tissue sample of Plymouth rose gentian at the U.S. Botanic Garden. (photo by Hilary-Morgan Watt)

Sabatia kennedyuana Fernald (Plymouth rose gentian), is a bog plant that is native to the east coast of North America but is only found in two widely separated areas: in the northeast in Massachusetts and Rhode Island and again in the south in North Carolina. In all locations it is endangered, threatened, or of special concern. The northern populations are adapted to bogs that were once under glaciers and the southern population live in fire adapted communities. Some scientists are considering recognizing these as two different species. Here we found the North Carolina population growing with pitcher plants (carnivorous).

Gardens such as this one are excellent places to see rare, beautiful and important plants that have their own story to share. We hope to help preserve part of that story through the preservation of the world’s plant genomes in biorepositories worldwide. Stay tuned and follow along with #SmithsonianGGI.