Plant Roots-Fungi Symbiosis Is Multifaceted

Plant Roots-Fungi Symbiosis Is Multifaceted

The most prevalent known plant symbiosis is the mutual relationship between the roots of vascular plants (plants with xylem and phloem that act as a hydraulic system to bring water and nutrients up from the soil to the leaves and food produced in the leaves to the rest of the plants) and arbuscular mycorrhizal fungi (AMF). Two recent research findings reveal that this symbiotic relationship is much more complex than previously thought. What was known previously was thatvascular plants provide sites all along their root systems where colonies of AMF can assemble and feed on the nutrients and food supplied by the plants. In return, the AMF supply phosphorus, nitrogen, and carbon in molecular forms that the vascular plants can readily assimilate. It was also known that AMF enhances the uptake of liquid water by the vascular plants.1

AMF nodules, found on the roots of over 80% of all vascular plant species, played a crucial role in facilitating the rapid colonization of the continental landmasses by vascular plants. Without this symbiotic and widespread relationship between AMF and vascular plants, neither soulish animals (birds and mammals) nor human beings would thrive on Earth. Both would lack the necessary supply of food and nutrients. The creation and maintenance of large-bodied soulish animals described in Genesis 1:21 and of humans in Genesis 1:26–27 would be impossible without the symbiotic connection between vascular plants and AMF being established first.

The two new studies were published in the June 16, 2017, issue of Science.  Teams led by Yina Jiang2 and Leonie Luginbuehl3 describe how ecologists previously thought that vascular plants supplied a variety of sugars to the AMF. However, as the two teams independently demonstrated, vascular plants also supply their symbiotic AMF with lipids, “thus providing the fungi with a robust source of carbon for their metabolic needs.”4 Because of this rich supply of carbon in the form of lipids, AMF are able to launch and sustain colonization along the entire root system to the great benefit of the vascular plants.

Like all complex symbiotic relationships manifested in nature, the mutual support that AMF and vascular plants provide for one another poses a profound challenge to evolutionary models for life. AMF cannot thrive without vascular plants, nor can the vascular plants thrive without AMF.

The challenge for evolutionary models is how to explain, by natural means, the simultaneous appearance of both vascular plants and AMF. An even greater challenge is: (1) how to explain the plants evolving structures in their root systems to house AMF, channel lipids and carbohydrate resources (sugars) to feed themselves, and enable them to build complex colonies; and (2) how to explain AMF evolving the means to harvest phosphorus, nitrogen, and carbon, transform them into forms suitable for vascular plants, and provide transportation systems to channel these resources into the plants’ root systems. Furthermore, evolutionary models must explain, by natural means, how AMF and vascular plant root systems were placed together so they could form and efficiently sustain their symbiotic relationships.

It seems to me that nothing less than a supernatural, super-intelligent Creator can explain all the intricate designs required in advance of launching and maintaining such complex symbiotic relationships. The complex symbiotic relationships between vascular plants and AMF testify, too, of the Creator’s desire to provide the human race with a rich supply of food and a diverse, stable, and abundant treasure chest of biodeposits.

Featured image: Flax root cortical cells containing paired arbuscules of fungi. 

Endnotes
  1. Gail W. T. Wilson et al., “Soil Aggregation and Carbon Sequestration Are Tightly Correlated with the Abundance of Arbuscular Mycorrhizal Fungi: Results from Long-Term Field Experiments,” Ecology Letters 12 (March 2009): 452–61, doi:10.1111/j.1461-0248.2009.01303.x.
  2. Yina Jiang et al., “Plants Transfer Lipids to Sustain Colonization by Mutualistic Mycorrhizal and Parasitic Fungi,” Science 356 (June 16, 2017): 1172–75, doi:10.1126/science.aam9970.
  3. Leonie H. Luginbuehl et al., “Fatty Acids in Arbuscular Mycorrhizal Fungi Are Synthesized by the Host Plant,” Science 356 (June 08, 2017): 1175–78, doi:10.1126/science.aan0081.
  4. Jiang et al., “Plants Transfer Lipids,” 1172.