Safeguarding plant genetic resources in the United States during global climate change

Authors: Volk, Gayle; Carver Jr, Daniel; Irish, Brian; MAREK, LAURA - Iowa State University; Frances, Anne; Greene, Stephanie; KHOURY, COLIN - San Diego Botanic Garden; Bamberg, John; DEL RIO, ALFONSO - University Of Wisconsin; Warburton, Marilyn; Bretting, Peter

Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/15/2023
Publication Date: 5/5/2023
Citation: Volk, G.M., Carver Jr., D.P., Irish, B.M., Marek, L., Frances, A.L., Greene, S.L., Khoury, C., Bamberg, J.B., Del Rio, A., Warburton, M.L., Bretting, P.K. 2023. Safeguarding plant genetic resources in the United States during global climate change. Crop Science. 63(4):2274-2296. https://doi.org/10.1002/csc2.21003.
DOI: https://doi.org/10.1002/csc2.21003

Interpretive Summary: Plant genetic resources (PGR) underpin the security of global agriculture by providing the plant materials needed for continued gains in crop productivity, efficiency, sustainability and adaptation to changing agricultural and environmental factors. Rapid global climate change and associated increase in severe weather represent particularly formidable challenges for conserving and using PGR through two complementary PGR management approaches. Ex situ conservation in genebanks seeks to maintain PGR true-to-type, with minimal loss or genetic changes through time; and in situ, or dynamic conservation in nature or in farmers’ fields, enables selective forces such as climate to determine the PGR’s evolutionary trajectories. Both PGR management approaches operate over extended timeframes—decades to centuries, or even millennia. Consequently, PGR managers must plan operations at these timescales, which can be especially complicated by rapid and unpredictable changes in the global climate. The USDA National Plant Germplasm System maintains over 605,000 accessions representing over 16,300 plant species in 22 genebank locations and support units. These PGR are maintained as seeds that must be periodically regenerated or as actively growing collections in fields, greenhouses/screenhouses, and in vitro. Several in situ reserves have also been established. The relationships between the crops and their growth environments are complex, and present unique challenges regarding their maintenance under a changing climate. This essay describes the potential effects of climate change on ex situ and in situ genebank management, with specific reference to the NPGS. The impact of climate change on plant maintenance and reproductive success, pollinators and beneficial insects, pathogens and pests, and infrastructure considerations are discussed. Some impacts of climate change on wild populations within NPGS in situ reserves are also included. We provide a novel online tool that presents temperature and precipitation data for NPGS locations. These data can be used for ongoing planning efforts, which are illustrated by a series of case studies whereby instances of climate change have already been observed for specific crops within the NPGS. Ongoing efforts to improve NPGS collection management in response to climate change require continued observations of the current effects, careful and innovative planning, and creative approaches to ensure that PGR are successfully maintained and available for future generations.

Technical Abstract: Plant genetic resources (PGR) underpin the security of global agriculture. Rapid global climate change presents formidable challenges for ex situ and in situ PGR conservation efforts that operate over extended timeframes. The USDA National Plant Germplasm System maintains over 605,000 accessions representing over 16,300 plant species in 22 genebank locations. These PGR are maintained as seeds that must be periodically regenerated, or as actively growing collections in fields, greenhouses, screenhouses, in situ reserves, and in vitro. The relationships between crops and their growth environments are complex, and present unique challenges regarding their maintenance under a changing climate. Here we present potential effects of climate change on ex situ maintenance and reproductive success, pollinators and beneficial insects, pathogens and pests, infrastructure considerations, and wild populations within NPGS in situ reserves. We provide a novel online tool that presents past U.S. temperature and precipitation data and future projections that provide data that to guide ongoing planning efforts. A series of case studies exemplify instances where climate change has already impacted NPGS activities. Ongoing efforts to improve NPGS collection management in response to climate change require continued observations of the current effects, careful and innovative planning, and creative approaches to ensure that PGR are successfully maintained and available for future generations.