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ARS Home » Plains Area » Temple, Texas » Grassland Soil and Water Research Laboratory » Research » Publications at this Location » Publication #387642
Research Project: Contributions of Climate, Soils, Species Diversity, and Management to Sustainable Crop, Grassland, and Livestock Production Systems

Location: Grassland Soil and Water Research Laboratory

Title: A generalist-specialist trade-off between switchgrass cytotypes impacts climate adaptation and geographic range

Author
item NAPIER, JOESPH - University Of Texas At Austin
item GRABOWSKI, PAUL - Genome Sequencing Center
item LOVELL, JOHN - Genome Sequencing Center
item BONNETTE, JASON - University Of Texas At Austin
item MAMIDI, SUJAN - Genome Sequencing Center
item GOMEZ-HUGHES, MARIE - University Of Texas At Austin
item VAN WALLENDAEL, ACER - Michigan State University
item WENG, XIAOYU - University Of Austin
item HANDLEY, LORI - Hudsonalpha Institute For Biotechnology
item KIM, MIN - Hudsonalpha Institute For Biotechnology
item BOE, ARVID - South Dakota State University
item Fay, Philip
item FRITSCHI, FELIX - University Of Missouri
item JASTROW, JULIE - Argonne National Laboratory
item LLOYD-REILLEY, JOHN - Natural Resources Conservation Service (NRCS, USDA)
item LOWREY, DAVID - Michigan State University
item MATAMALA, ROSER - Argonne National Laboratory
item Mitchell, Robert - Rob
item ROUQUETTE, FRANCIS - Texas Agrilife Research
item WU, YANQI - Oklahoma State University
item WEBBER, JENELL - Hudsonalpha Institute For Biotechnology
item JONES, TERESA - Oklahoma State University
item BARRY, KERRIE - Lawrence Berkeley National Laboratory
item GRIMWOOD, JANE - Hudsonalpha Institute For Biotechnology
item SCHMUTZ, JEREMY - Hudsonalpha Institute For Biotechnology
item JUENGER, THOMAS - University Of Texas At Austin

Submitted to: Proceedings of the National Academy of Sciences (PNAS)
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/22/2022
Publication Date: 4/4/2022
Citation: Napier, J.D., Grabowski, P., Lovell, J.T., Bonnette, J., Mamidi, S., Gomez-Hughes, M.J., VanWallendael, A., Weng, X., Handley, L.H., Kim, M.K., Boe, A.R., Fay, P.A., Fritschi, F.B., Jastrow, J.D., Lloyd-Reilley, J., Lowrey, D.B., Matamala, R., Mitchell, R., Rouquette, F.M., Wu, Y., Webber, J., Jones, T., Barry, K., Grimwood, J., Schmutz, J., Juenger, T.E. 2022. A generalist-specialist trade-off between switchgrass cytotypes impacts climate adaptation and geographic range. Proceedings of the National Academy of Sciences(PNAS). 119(15). Article e2118879119. https://doi.org/10.1073/pnas.2118879119.
DOI: https://doi.org/10.1073/pnas.2118879119

Interpretive Summary: Polyploidy, the duplication of whole genomes in plants, is a unique form of heritable genetic variation with pronounced evolutionary and plant breeding implications. Polyploidy can novel variation in plant species and provide a means by which plant can adapt to new environments, however little is known about how polyploid forms arise and how they may have adaptive advantage. Through a combination of genomic, quantitative genetic, landscape, and niche modeling approaches we uncovered evidence for the genetic origins, niche differentiation, and differential environmental sensitivity of two polyploid forms (4X, 8X) of switchgrass (Panicum virgatum). These findings suggest that polyploid forms of switchgrass exist across broad portions of the species range because they represent two different adaptive strategies (8X: generalist, 4X: specialist). This unique combination of strategies in a single species has allowed the expansion of switchgrass’ ecological niche and may represent a valuable breeding resource.

Technical Abstract: Polyploidy results from whole-genome duplication and is a unique form of heritable variation with pronounced evolutionary implications. Different ploidy levels, or cytotypes, can exist within a single species, and such systems provide an opportunity to assess how ploidy variation alters phenotypic novelty, adaptability, and fitness, which can in turn drive the development of unique ecological niches that promotes coexistence of multiple cytotypes. Switchgrass, Panicum virgatum, is a widespread, perennial C4 grass in North America with multiple naturally occurring cytotypes, primarily tetraploids (4X) and octoploids (8X). Using a combination of genomic, quantitative genetic, landscape, and niche modeling approaches we detect divergent levels of genetic admixture, evidence of niche differentiation, and differential environmental sensitivity between switchgrass cytotypes. Taken together, these findings support a generalist (8X)-specialist (4X) tradeoff. Our results indicate that the 8X represent a unique combination of genetic variation that has allowed the expansion of switchgrass’ ecological niche and thus putatively represents a valuable breeding resource.