@article{eaeba3b302b04fddbd3299e99b63e7ae,
title = "Sympatric pairings of dryland grass populations, mycorrhizal fungi and associated soil biota enhance mutualism and ameliorate drought stress",
abstract = "There is evidence that the distribution of ecotypes of plants and their symbiotic arbuscular mycorrhizal (AM) fungi and other associated soil biota may be structured by the availability of essential soil nutrients; and that locally adapted partnerships most successfully acquire limiting nutrients. This study tests the hypotheses that plant genotypes are adapted to the water availability of their local environment, and this adaptation involves associations with local soil biota, including AM fungi. We grew semi-arid Bouteloua gracilis ecotypes from relatively wet and dry sites, with either sympatric or allopatric soil inoculum under moderate and extreme soil drying treatments to examine (a) how varying degrees of water limitation influence grass responses to soil biota and (b) the relationship between AM fungal structures and the responses. Under extreme soil drying, the dry site ecotype tended to perform better than the wet site ecotype. Both ecotypes performed best in either drying treatment when inoculated with their sympatric soil biota. Sympatric pairings produced more AM fungal hyphae, arbuscules and dark septate fungi. Extreme soil drying tended to accentuate these apparent benefits of sympatry to both plants and fungal symbionts, relative to the moderate drying treatment. Our findings support the hypothesis that AM symbioses help Bouteloua gracilis ecotypes adapt to local water availability. This conclusion is based on the observations that as water became increasingly limited, sympatric partnerships produced more AM fungal hyphae and arbuscules and fewer vesicles. The abundances of hyphae and arbuscules were positively correlated with plant growth, suggesting that in sympatric pairs of plants and AM fungi, allocation to fungal structures is optimized to maximize benefits and minimize the costs of the symbioses. This provides strong evidence that co-adaptation among plants and their associated AM fungi can ameliorate drought stress. Synthesis. Our study documents the role of locally adapted soil borne plant symbionts in ameliorating water stress. We found a relationship between AM fungal structures in roots and plant performance. Generally, plants and fungi from the same site resulted in more positive effects on plant growth.",
keywords = "Bouteloua gracilis, arbuscular mycorrhizas, climate change, co-adaptation, drought, local adaptation, soil organisms",
author = "Remke, {Michael J.} and Johnson, {Nancy C.} and Jeffrey Wright and Matthew Williamson and Bowker, {Matthew A.}",
note = "Funding Information: This work was supported by the McIntire‐Stennis Cooperative Forestry Research Program [grant no. 2014‐32100‐06014/project accession no. 1001799] from the USDA National Institute of Food and Agriculture and the Bureau of Land Management's Colorado Plateau Native Plants Program (Cooperative Agreement L17AC00031). We would also like to thank the NAU Genes to Environment extension of the NSF's IGERT program, Achievement Rewards for College Scientists (ARCS), and the ESA SEEDS program for their support. We would like to thank the Grand Canyon Trust, especially their volunteers, for their support of this project. Additionally, we would like to thank the Bureau of Land Management, United States Forest Service and Babbitt Ranches for the access to their lands for research. Anita Antoninka also provided invaluable help in training, in methodology and guidance on measurements, and Amanda Knauf provided assistance in the field and the glasshouse. Special thanks to Gail Wilson and her laboratory for contributing the PLFA and NLFA analysis. We would also like to thank Lela Andrews and Bo Stevens for providing support in analysing fungal community data. No conflicts of interests exist with any of the authors in the publication of this manuscript. Funding Information: This work was supported by the McIntire-Stennis Cooperative Forestry Research Program [grant no. 2014-32100-06014/project accession no. 1001799] from the USDA National Institute of Food and Agriculture and the Bureau of Land Management's Colorado Plateau Native Plants Program (Cooperative Agreement L17AC00031). We would also like to thank the NAU Genes to Environment extension of the NSF's IGERT program, Achievement Rewards for College Scientists (ARCS), and the ESA SEEDS program for their support. We would like to thank the Grand Canyon Trust, especially their volunteers, for their support of this project. Additionally, we would like to thank the Bureau of Land Management, United States Forest Service and Babbitt Ranches for the access to their lands for research. Anita Antoninka also provided invaluable help in training, in methodology and guidance on measurements, and Amanda Knauf provided assistance in the field and the glasshouse. Special thanks to Gail Wilson and her laboratory for contributing the PLFA and NLFA analysis. We would also like to thank Lela Andrews and Bo Stevens for providing support in analysing fungal community data. No conflicts of interests exist with any of the authors in the publication of this manuscript. Publisher Copyright: {\textcopyright} 2020 British Ecological Society Copyright: Copyright 2021 Elsevier B.V., All rights reserved.",
year = "2021",
month = mar,
doi = "10.1111/1365-2745.13546",
language = "English (US)",
volume = "109",
pages = "1210--1223",
journal = "Journal of Ecology",
issn = "0022-0477",
publisher = "Wiley-Blackwell",
number = "3",
}