Using Biodiversity

Seed collection at the herbarium, Penn State University

To continue with the discussion of the Global Strategy for Plant Conservation (GSPC) targets from the last post, they deal with not only conserving plant species, but using them.  The rising human population exacerbates environmental problems and the demand for resources.  Sustainability is a term that suggests a solution:  employing resources in a way that can be stably continued over time and relying on resources that can be stably renewed.  Many themes come into play in this effort from saving seeds to using plants’ genetic diversity and the rich plant knowledge base of indigenous peoples. 

Seeds have always been of interest to botanists; they are an easy way to transport and share plants.  Luca Ghini did not just create one of the first herbaria, he also kept a catalogue of the seeds he collected from plants at the botanical garden of Pisa he founded.  He sent the list to other botanists and offered them seeds of any listed species.  However, seed saving was going on long before that.  Farmers kept seed to plant the next year’s crops, taking those from the best performing plants, thus selectively breeding for particular traits.

As agriculture scaled up and became more mechanized, a different model developed, with farmers buying seed from companies that grew plants for seeds, often with limited genetic variation.  Recently, seeds for many crops are from genetically engineered plants with traits like increased nutrient levels, resistance to pests, or faster growth.  Using these seeds decreases genetic variation in crop plants, with resulting susceptibility to pathogens.  With greater genetic diversity, at least a portion of the plants would survive.  Some farmers and gardeners have saved seed from what are called heirloom varieties or landraces, strains that were developed to grow well in particular areas, rather than being mass-produced.  These growers were doing a service to the larger community by conserving and propagating biodiversity and are now more appreciated. 

Many herbaria have seed collections; they were popular early in the century, and were often sold in custom-made cases, with each seed type in a small labeled vial.  These samples were not meant for propagation—seeds usually lose their viability rather quickly.  Instead, the seeds aided in identifying species that might have been collected with seeds.  In most cases the seeds are so old that they will not germinate, though they can be a source of DNA.  Seedbanks, on the other hand, are designed to save seed for future planting and some are of long standing.  They are crucial in preserving genetic diversity of crop plants and their wild relatives, and also of plant biodiversity in general.  Many nations have seeds banks, especially for agricultural crops and also for horticulturally important species.  The Russian botanist Nikolai Vavilov created an early bank for the many seeds he collected during his surveys of regions where various crop plants had originated.  The massive Svalbard Global Seed Bank built into permafrost within the Arctic Circle focuses on crop species, their wild relatives, and landraces.  It was created as a backup facility for seed collections throughout the world, in case any suffer damage.  The largest seed repository is the Millennium Seed Bank managed by Kew that aims to store seed for as many wild plant species as possible extending beyond the useful.

At the Max Planck Institute for Plant Breeding Research, the Ross Potato Herbarium was founded after its namesake collected specimens as well as seed potatoes in South America in 1959, and it grew as additional material was added.  The USDA has a number of facilities for germplasm (seeds, cuttings, and plant tissue) throughout the country, and the National Arboretum in Washington, DC hosts the USDA’s herbarium.  In the United States, many crop-related specimens are housed in the institutions that grew out of the nineteenth-century land grant colleges.  These herbaria often have large collections of cultivated plant specimens because of their strong horticulture and agriculture programs.  The University of California, Davis is known for these, and being in California, it had a viticultural herbarium of grape vine specimens that has now been incorporated into the general herbarium. 

Some herbaria, particularly those with ties to indigenous peoples and to the high-diversity areas where many reside can be particularly focused on species that have agricultural and medicinal uses.  These communities are also the source for many plant varieties that are now of interest because they are landraces grown for generations and are outside of the agricultural-industrial complex.  It makes sense that if biodiversity is important for sustainable agriculture, then focus needs to be put on working with local communities, as has been done for many years in collecting potato varieties in the Andes for the International Potato Center in Lima, Peru.  This center and others around the world that focus on specific crops such as rice, wheat and corn not only store valuable genetic material but also do research on plant varieties with increased nutrients and other useful characteristics.  They also work with local populations in finding ways to make agriculture sustainable.  There are efforts to move away from concentrating on a single crop and create agricultural practices less damaging to soil and surrounding ecosystems.  Mixing crops including within forest environments instead of completely cutting down the trees are becoming more common initiatives and definitely in line with the GSPC. 

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