As the 2010 United Nations International Year of Biodiversity comes to a close, the Missouri Botanical Garden (MBG) and the Royal Botanic Gardens, Kew (RBG Kew) announce the completion of The Plant List. This landmark international resource is a working list of all land plant species1, fundamental to understanding and documenting plant diversity and effective conservation of plants.

The completion of The Plant List accomplishes Target 1 of the Global Strategy for Plant Conservation (GSPC), which called for a widely accessible working list of known plant species as a step towards a complete world flora. The Plant List can be accessed by visiting www.theplantlist.org.

“The on-time completion of The Plant List is a significant accomplishment for the Royal Botanic Gardens, Kew and the Missouri Botanical Garden, and our partners worldwide,” said Professor Stephen Hopper, Director, Royal Botanic Gardens, Kew. “This is crucial to planning, implementing and monitoring plant conservation programs around the world.”

Without accurate names, understanding and communication about global plant life would descend into inefficient chaos, costing vast sums of money and threatening lives in the case of plants used for food or medicine. The Plant List provides a way of linking the different scientific names used for a particular species together, thus meeting the needs of the conservation community by providing reliable names for all communication about plants and their uses.

The Plant List includes 1.25 million scientific plant names, of which 1.04 million are names of species rank. Of the species names included in The Plant List, about 300,000 (29 percent) are accepted names for species and about 480,000 (46 percent) are recorded as synonyms of those species. The status of the remaining 260,000 names is “unresolved” since the contributing data sets do not contain sufficient evidence to decide whether they should be accepted names or synonyms.

The Plant List includes a further 204,000 scientific plant names of infraspecific taxonomic rank linked to those species names. These numbers will change in the future as data quality improves.

“All validly published names for plants to the level of species have been included in The Plant List, the majority of them synonyms; no names have been deleted,” said Dr. Peter H. Raven, President Emeritus, Missouri Botanical Garden.

Since 2008, botanists and information technology specialists at MBG and RBG Kew have been developing and testing an innovative new approach to generating The Plant List. The approach involved merging existing names and synonymy relationships from the Royal Botanic Gardens, Kew’s World Checklist of Selected Plant Families with over one million plant names from Tropicos, which has been the Missouri Botanical Garden’s main online taxonomic resource since 1982.

Researchers and specialists used names and synonymy relationships from regional floras and checklists and worked out a rules-based approach2 to merge them with RBG Kew’s records into The Plant List. The project has relied on collaboration with other botanists and their institutions around the world working towards GSPC Target 1; major contributions have come from The International Compositae Alliance (www.compositae.org), International Legume Database & Information Service (www.ildis.org) and The International Plant Names Index (www.ipni.org).

Taxonomic breakthrough

“This is a breakthrough,” said Chuck Miller, Vice President of Information Systems at the Missouri Botanical Garden. “By capturing taxonomic knowledge into a rulebase, computers could be employed to aid the task of sorting out the millions of plant name records assembled over the past two decades in Tropicos, the World Checklist of Selected Plant Families and other sources to produce this product that achieves the Global Strategy for Plant Conservation Target 1.”

The Global Strategy for Plant Conservation (GSPC) was first proposed at the XVI International Botanical Congress in St. Louis in 1999. It was adopted in April 2002 by the Convention on Biological Diversity as a guide and framework for plant conservation policies and priorities worldwide at all levels. The GSPC consists of a plan containing 16 targets to address the loss of plant species around the world. At the 10th Meeting of the Conference of the Parties to the Convention on Biological Diversity held in Nagoya, Japan in October 2010, an updated plan was adopted for the period of 2011 through 2020 with updated targets. The first three objectives of the new Global Strategy for Plant Conservation are that plant diversity is well understood, documented and recognized; plant diversity is urgently and effectively conserved; and plant diversity is used in a sustainable and equitable manner. The completion of The Plant List is a significant step towards the new GSPC Target 1 – to create an online flora of all known plants by 2020.

“Having an accurate and comprehensive list of the world’s flora will be a fundamental requirement to underpin future plant conservation efforts,” said Dr. Peter Wyse Jackson, President, Missouri Botanical Garden. “The Plant List provides this new resource and will be widely used and much welcomed. Meeting this important GSPC target for 2010 represents a remarkable achievement for all those involved and provides the basis on which we can build towards the newly adopted 2020 target.”

“For anyone that depends upon reliable information about plants, including professionals working in health, food and agriculture or rural development, The Plant List represents a significant information product,” said Bob Allkin, Information Project Manager, Royal Botanic Gardens, Kew.

“It will enable such professionals to find all published research about a given plant regardless of which name was used in those publications.”

With scientists working in 38 countries on six continents around the globe, the Missouri Botanical Garden has one of the three largest plant science programs in the world. Its mission is “to discover and share knowledge about plants and their environment in order to preserve and enrich life.” The Garden focuses its work on areas that are rich in biodiversity yet threatened by habitat destruction, and operates the world’s most active research and training programs in tropical botany.

Garden scientists collaborate with local institutions, schools and indigenous peoples to understand plants, create awareness, offer alternatives and craft conservation strategies. The Missouri Botanical Garden is striving for a world that can sustain us without sacrificing prosperity for future generations, a world where people share a commitment to managing biological diversity for the common benefit.

Today, 151 years after opening, the Missouri Botanical Garden is a National Historic Landmark and a center for science, conservation, education and horticultural display.

The Royal Botanic Gardens, Kew is a world-famous scientific organization, internationally respected for its outstanding living collection of plants and world-class herbarium as well as its scientific expertise in plant diversity, conservation and sustainable development in the U.K. and around the world. Kew Gardens is also a major international visitor attraction. Its landscaped 132 hectares and Kew's country estate, Wakehurst Place, attract nearly 2 million visitors every year. Kew was made a UNESCO World Heritage Site in July 2003 and celebrated its 250th anniversary in 2009.

Wakehurst Place is home to Kew's Millennium Seed Bank, the largest wild plant seed bank in the world. The Royal Botanic Gardens, Kew and its partners have collected and conserved seed from 10 percent of the world's wild flowering plant species (c. 30, 000 species) and aim to conserve 25 percent by 2020.