By Gina Myers, MEng ’20 (BIOE)The mention of fungi often bears ideas of a deadly inoculation that is anything but desirable. The notion of pathology is understandable, after the destruction wrought by fungal diseases like Dutch Elm and Needle Blight. Though fungi have had their fair share of negative exposure, there’s more happening beneath the surface than meets the eye. Increasingly, the critical role fungi play in the health of terrestrial ecosystems is gaining attention-and deservedly so. Symbiotic fungi, termed “mycorrhizae”, provide enormous benefit to their vascular plant hosts. How exactly can they do this, and why are mycorrhizae so important to the earth in an era of changing ecosystems and climate crisis?
Climate change and human destruction are altering the world we live in.With biodiverse habitats disappearing at a rate never before seen, the survival and resilience of the earth rely on the ability of the natural environment to grow and thrive. Mycorrhizae are present in over 90% of known vascular land plants (“Hidden Partners”). They are key drivers of nutrient uptake, water availability, and carbohydrate sourcing in an ecosystem. With an advanced understanding of this symbiotic system, new possibilities present themselves in the form of habitat engineering and bioremediation. Imagine an ecosystem starved for nutrients after years of mismanage soil and parched from an extended period of drought. It can be nearly impossible to convince plants and trees to grow- let alone thrive- in settings like these. We need plants and forests to spring up, transforming destitute lands. Mycorrhizal inoculation of plant roots catalyzes the establishment and development of a thriving ecosystem. In the same way, with renewed mycorrhizal presence, a struggling ecosystem can return to its former glory. Often an imbalance of nutrients, water, or species puts an ecosystem on a path of poor health and destruction, which can be halted or reversed through careful curation of nutrients and fungal strains. The figure to the left shows a cross-sectional view of huge mycorrhizae surrounding the nascent root system of a pine seedling. (Source: “Mycorrhizae Benefits to Your Trees.”)
How exactly does the symbiosis between plants and mycorrhizae work?In this interaction, each species derives sufficient benefit for the relationship for it to be evolutionarily favorable- even preferred. From the plant’s perspective, a fungal partner means increased nutrient and water availability, as well as a more robust root system. The fugal hyphae extend well beyond the roots of the plant, transporting water and nutrients far from the circumference of soil that the plant would be able to access. This means that the functional area available to the plant to reach what it needs from the soil is increased by up to 50 times (“Benefits of Mycorrhizae”). Genes that enable efficient nutrient assimilation and uptake are present in the fungal genome. These make key drivers of plant growth including nitrogen, phosphorus and potassium available to the plant (Ai-Hua, Ceccaroli) following assimilation by the fungus. Similarly, mycorrhizae absorb moisture from afar and transport it right to the plant’s roots (“Benefits of Mycorrhizae”). The fungi provide all this in return for easy access to carbohydrates, which are generated during the Calvin Cycle inside the plant cell using energy from the sun (Yang). These carbohydrates become available to the fungi through the root system of the plant and promote fungal growth by lowering the barrier to energy acquisition. Symbiotic interactions are orchestrated for each species and are foundational to the health of the ecosystem.
By harnessing the power of mycorrhizal fungi, we can re-imagine forests to be robust and stable ecosystems.Forests rooted in a strong mycorrhizal partnership are not only healthier, they are resilient to the threats posed by climate change and human infiltration. The ability to engineer plant-fungal symbiosis in ecosystems across the globe could transform how we fight climate change. Forests nourish the land, and fungi nourish the forests.
Using fungi, we can halt and reverse the downward trajectory of terrestrial ecosystems in the modern era.
About the author:Gina Myers is a natural leader and brings a fresh perspective to engineering and leadership from her interests in endurance sports and environmental stewardship. She is a top performer in all her endeavors and her background both as a culinary professional and bioengineer contains numerous honors. She received an Associate’s Degree in Culinary Arts from the Culinary Institute of America after graduating high school at age 16. She then made a sharp left turn away from the culinary world and obtained a bachelor’s degree in Biomedical Engineering from the University of the Pacific in just over three years. After an internship at the Broad Institute of MIT and Harvard studying KRAS cancer genetics and two years working at BioMarin Pharmaceuticals to develop a gene therapy cure for Hemophilia, she decided to invest in her entrepreneurial ambitions by attending UC Berkeley’s Fung Institute for Engineering Leadership, where she currently studies Bioengineering. Whether training for an ultramarathon or the Ironman triathlon world championships, working with a team to bring a microfluidic design to life, or passionately making the case for an environmental or political issue, her motivation and conceptual and organizational abilities are valued by her colleagues and mentors. Connect with Gina.
- Ai-Hua, Xu, et al. “Differential Responses of Water Uptake Pathways and Expression of Two Aquaporin Genes to Water-Deficit in Rice Seedlings of Two Genotypes.” Rice Science, vol. 24, no. 4, 2017, pp. 187–197., doi: 10.1016/j.rsci.2017.03.001.
- A&L Plains Agricultural Laboratories “806–763-4278.” SOIL, Lubbock, Texas http://al-labsplains.com/soil/2511974.
- Bai, Hua, et al. “The Nitrate Transporter (NRT) Gene Family in Poplar.” PLoS ONE, vol. 8, no. 8, 2013, doi:10.1371/journal.pone.0072126.
- “Beautiful Forest.” Desktop Nexus Wallpapers.
- Ceccaroli, P., et al. “Genomic Profiling of Carbohydrate Metabolism in the Ectomycorrhizal Fungus Tuber Melanosporum.” New Phytologist, vol. 189, no. 3, 2010, pp. 751–764., doi:10.1111/j.1469–8137.2010.03520.x.
- Crouse, David. “1. Soils and Plant Nutrients.” NC State Extension Publications.
- “Field Use of Tensiometers 92–38.” Department of Land, Air and Water Resources — UC Davis :: Field Use of Tensiometers.
- “Hidden Partners: Mycorrhizal Fungi and Plants.” NYBG.org.
- Johnson, N. C., et al. “Functioning of Mycorrhizal Associations along the Mutualism-Parasitism. Continuum.” New Phytologist, vol. 135, no. 4, 1997, pp. 575–585., doi:10.1046/j.1469-8137.1997.00729.x.
- Landscape-Water-Conservation. “Benefits of Mycorrhizae.” Water Conservation for Lawn and Landscape, 29 July 2019.
- Le Pioufle, Olivia, and Stéphane Declerck. “Reducing Water Availability Impacts the Development of the Arbuscular Mycorrhizal Fungus Rhizophagus Irregularis MUCL 41833 and Its Ability to Take Up and Transport Phosphorus Under in Vitro Conditions.” Frontiers in Microbiology, Frontiers Media S.A., 11 June 2018.
- Liu, Jianjian, et al. “The Potassium Transporter SlHAK10 Is Involved in Mycorrhizal Potassium Uptake.” Plant Physiology, vol. 180, no. 1, 2019, pp. 465–479., doi:10.1104/pp.18.01533.
- “Oregon Hikers.” News Article about Unhealthy Forests — Oregon Hikers.
- Sevugapperumal, Nakkeeran & S., Vinodkumar & Dheepa, Ramasamy & Renukadevi, P.. (2018).
- Diseases of Carnation and their management. “Soil Water Content.” Soil Water Content — an Overview | ScienceDirect Topics.
- Tian, Chunjie, et al. “Regulation of the Nitrogen Transfer Pathway in the Arbuscular Mycorrhizal Symbiosis: Gene Characterization and the Coordination of Expression with Nitrogen Flux.”
- Plant Physiology, vol. 153, no. 3, June 2010, pp. 1175–1187., doi:10.1104/pp.110.156430.
- Wang, Xiaoli, et al. “Nitrate Accumulation and Expression Patterns of Genes Involved in Nitrate Transport and Assimilation in Spinach.”
- Molecules, vol. 23, no. 9, Feb. 2018, p. 2231., doi:10.3390/molecules23092231.
- World Bank. A HANDBOOK FOR ORGANIC GROWERS AND GARDENERS IN TEMPERATE AND SUB-TROPICAL REGIONS, Amigo Cantisano, Organic Ag Advisors.
- Yang, Bo, et al. “Genetic Engineering of the Calvin Cycle toward Enhanced Photosynthetic CO2 Fixation in Microalgae.” Biotechnology for Biofuels, vol. 10, no. 1, May 2017,doi:10.1186/s13068–017–0916–8.
- Yang, Zefeng, et al. “Molecular Evolution and Functional Divergence of HAK Potassium Transporter Gene Family in Rice (Oryza Sativa L.).” Journal of Genetics and Genomics, vol. 36, no. 3, 2009, pp. 161–172., doi:10.1016/s1673-8527(08)60103–4.
- Yukalov, V.i., et al. “Modeling Symbiosis by Interactions through Species Carrying Capacities.”
- Physica D: Nonlinear Phenomena, vol. 241, no.15, 2012, pp. 1270–1289., doi:10.1016/j.physd.2012.04.005.
Op-ed: How the filamentous underworld will help our forests survive was originally published in Berkeley Master of Engineering on Medium, where people are continuing the conversation by highlighting and responding to this story.