Most forests are recovering from human land use, making it critical to understand the effect of disturbance on forest recovery. Forests of the eastern United States have a long history of land use, but it is unknown whether historical disturbances have contributed to their transition from ectomycorrhizal (ECM) to arbuscular mycorrhizal (AM) tree dominance. Disturbance may promote nitrogen (N)‐fixing trees in early succession, which can elevate soil N availability even after they die. Higher soil N availability may facilitate the competitive success of AM trees over ECM trees, but such ‘N fixer founder effects’ have not been empirically tested. Here, we analysed data from three land‐use disturbances in a temperate forest historically dominated by ECM trees: selective‐cutting (ranging from 0 to 52 m2 ha−1), clear‐cutting and agricultural abandonment. These disturbances occurred at different times, but long‐term data capture 3–7 decades of forest recovery. We found that the AM tree fraction in contemporary forests was 2, 4, and 6‐fold higher following selective‐cutting, clear‐cutting and agricultural abandonment, respectively, compared to forest composition in 1934. Across these disturbances we also observed an increasing abundance of the N fixer black locust immediately following disturbance. Using a simulation model parameterized by data from black locust, we estimated historicalmore »
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.
Plant–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 of We assessed shoot and root biomass, shoot P more » 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.
- Award ID(s):
- 1946093
- Publication Date:
- NSF-PAR ID:
- 10449323
- Journal Name:
- PLANTS, PEOPLE, PLANET
- Volume:
- 3
- Issue:
- 5
- Page Range or eLocation-ID:
- p. 578-587
- ISSN:
- 2572-2611
- Publisher:
- Wiley Blackwell (John Wiley & Sons)
- Sponsoring Org:
- National Science Foundation
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Abstract Synthesis and applications . Our findings suggest that common land use practices and black locust, a native N fixer, can reduce the dominance of ECM trees. If N fixers are likely to proliferate following disturbance, we might maintain ECM dominance by cutting trees at low densities and by applying prescribed fire to remove N. -
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