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Societal Impact StatementAgricultural practices have had a negative impact on the physical, chemical, and biological components of soil. Perennial cropping systems that facilitate positive soil microbial interactions could not only rebuild soils but also sustain productivity through expected variations in environmental conditions. Here, we show the presence of arbuscular mycorrhizal (AM) fungi, soil symbionts that can improve host performance and soil health, increased the growth of intermediate wheatgrass, a novel perennial grain crop, in populations that have been increasingly bred for desirable agricultural characteristics. The right pairing of intermediate wheatgrass and a beneficial AM fungal community could lead to more sustainable agroecosystems. SummaryIntermediate wheatgrass (IWG) is a novel perennial grain that can provide many soil health benefits in agroecosystems; however, little is known about how selection for agronomic traits has impacted interactions with soil biota. Here, we assess how the selection for agronomic traits in IWG has impacted its relationship with arbuscular mycorrhizal (AM) fungi.First, growth response to AM fungi was compared across five generations of IWG with varying degrees of selection. Second, variation in AM fungal responsiveness was compared among genets of IWG individuals within a more advanced generation. Finally, a meta‐analysis was performed on all published studies exploring AM fungal inocula effects on IWG performance to increase understanding of selection effects.AM fungal responsiveness increased with selection for agronomic traits, responsiveness varied among genets in the advanced generation, and a majority of genets performed better in the presence of AM fungi. The meta‐analysis supported the findings that AM fungal responsiveness has increased with selection in IWG.Further studies are needed to realize the combined potential soil health and sustainability benefits of IWG and AM fungi, including assessment of symbiotic benefits beyond biomass production, identification of IWG traits correlated with responsiveness, and characterization of AM fungal community response to IWG.
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Utilizing mycorrhizal responses to guide selective breeding for agricultural sustainability
Societal Impact Statement Agriculture touches all aspects of society and global environmental health. Dwindling phosphorous reserves are a looming crisis for civilization, and soil erosion typically far outpaces pedogenesis. Improving plant–mycorrhizal symbioses can enhance sustainable agriculture because mycorrhizas typically improve host‐plant nutrition and stabilize soils. Selective breeding of plants that gain greater benefits from mycorrhizas can provide considerable economic and environmental benefits. Our assessments demonstrate switchgrass genetic improvement increased or maintained production of two populations, and low‐input breeding increased mycorrhizal responsiveness, compared to parent lines. Selecting for increased mycorrhizal reliance may be an effective strategy for more sustainable and economical agricultural production. SummaryPlant–mycorrhizal interactions are not typically assessed in crop breeding programs. Our experiment addresses this by determining host‐plant outcomes of newly developed synthetic (agronomic) populations compared with parent lines, following low‐input selective breeding. Assessing the potential of low‐input breeding to enhance crop mycorrhizal benefits is a critical step toward more sustainable agricultural production.We compared four synthetic populations ofPanicum virgatum, from a low‐input biofuel breeding program at Oklahoma State University, to corresponding parent lines. Plants were grown in a greenhouse in native prairie soils that were either steam‐pasteurized (nonmycorrhizal) or non‐steamed (mycorrhizal).We assessed shoot and root biomass, shoot P concentration and P content, mycorrhizal growth response (MGR), and mycorrhizal phosphorous response (MPR). Importantly, we provide novel evidence that low‐input selective breeding increased mycorrhizal reliance of switchgrass synthetics compared to parent lines, with implications for global agricultural systems.There are substantial opportunities for plant traits associated with increased MGR and MPR to be transferred to a wide array of crops. Our findings indicate low‐input selective breeding can improve MGR and MPR. We propose these traits serve as a useful proxy for host‐plant mycorrhizal reliance, facilitating successful hologenome breeding to reduce fertilizer requirements.
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- Award ID(s):
- 1946093
- PAR ID:
- 10449324
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- PLANTS, PEOPLE, PLANET
- Volume:
- 3
- Issue:
- 5
- ISSN:
- 2572-2611
- Page Range / eLocation ID:
- p. 578-587
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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