Rhizophagy Cycle: An Oxidative Process in Plants for Nutrient Extraction from Symbiotic Microbes
The rhizophagy cycle is an incredible process that plants use to cultivate and extract nutrients from microbes, boosting plant health, nutrient uptake, and resilience. Understanding this cycle offers valuable insights into how farmers can reduce fertiliser inputs while improving crop performance.
To see the initial study on Dr James White’s rhizophagy cycle, you can find it here.
In this article, we’ll break down how the rhizophagy cycle works, its benefits, and how you can integrate it into your farming system.
But first, watch us explain it in the video below. It’s from our YouTube channel Agriculture Explained, so make sure to subscribe!
What is the Rhizophagy Cycle?
The rhizophagy cycle is an interaction between plants and microbes where bacteria and fungi enter plant root cells, are stripped of their cell walls, and release nutrients before being expelled back into the soil to repeat the process.
Unlike traditional nutrient uptake, where plants rely on dissolved minerals in the soil, this system allows plants to directly digest microbes for nutrients. It also enhances root development, strengthens disease resistance, and improves stress tolerance.
The Process: How Plants “Farm” Microbes
Root Exudates Attract Microbes
- Plants release root exudates (sugars, proteins, and organic acids) into the soil, stimulating microbial populations.
- This encourages beneficial bacteria and fungi, particularly yeasts, to move toward the root tip.
Microbes Enter the Root
- At the growing root tip (specifically in the meristematic cells), microbes slip between the cell wall and cell membrane of the root cells.
- This only occurs during active cell division, creating a unique entry point.
Reactive Oxygen Strips Microbial Cell Walls
- Once inside, the plant produces reactive oxygen species (superoxide), stripping the microbes of their cell walls.
- These cell walls contain nitrogen, phosphorus, calcium, magnesium, iron, and trace minerals, which are then absorbed by the plant.
Microbes Stimulate Root Hair Formation
- As the root continues to grow, it forms root hairs, which elongate and eventually expel the microbes back into the soil.
- Once in the soil, the microbes regenerate their cell walls, completing the cycle.
The Microbes Repeat the Process
- The expelled microbes continue to multiply in the rhizosphere, ensuring a continuous supply of nutrient-rich organisms.
This self-sustaining cycle allows plants to harvest nutrients in an organic, highly efficient way without relying solely on fertiliser inputs.
Benefits of the Rhizophagy Cycle
Increased Nutrient Acquisition
- Microbes provide organic forms of nitrogen, which are easier for plants to use than inorganic fertilisers.
- The cycle enhances the uptake of NPK, calcium, magnesium, and trace minerals.
Improved Plant Growth
- The cycle stimulates root hair development, increasing water and nutrient absorption.
- Microbial interactions also enhance hormone production, leading to better plant development.
Reduced Oxidative Stress
- Plants exposed to the rhizophagy cycle develop higher antioxidant levels, making them more resistant to drought, salinity, and pest pressure.
Enhanced Disease Resistance
- The cycle triggers systemic resistance in plants, making them more resilient against pathogens.
- Expelled microbes compete with harmful organisms in the soil, reducing the likelihood of infection.
Pest Deterrence
- Plants undergoing the rhizophagy cycle accumulate compounds that deter insect herbivory, reducing pest damage.
Weed Suppression
- Each plant species cultivates its own microbial community.
- Weeds growing in a dominant crop’s microbial environment may experience reduced growth, leading to natural suppression.
Why the Rhizophagy Cycle is Underutilised in Modern Agriculture
Many conventional farming practices disrupt this cycle, reducing its effectiveness. Some key issues include:
- Excessive Tillage – Destroys microbial habitats and breaks fungal networks.
- High-Analysis Fertilisers – Overuse of synthetic nitrogen suppresses microbial diversity.
- Fungicides & Herbicides – Harm beneficial fungi and bacteria, limiting microbial participation in the cycle.
To restore this natural system, we need to focus on regenerative soil management.
How to Activate the Rhizophagy Cycle on Your Farm
Maximise Photosynthesis
- Healthy plants produce more root exudates, which stimulate microbial populations.
- Apply essential minerals like magnesium, iron, phosphorus, boron, and nitrogen to support photosynthesis.
Extend the Growing Season with Cover Crops
- Conventional cropping systems only utilise 3-4 months of photosynthesis per year.
- Adding a cover crop extends root exudation, supporting microbes year-round.
Apply Microbial Inoculants to Seeds
- Coating seeds with beneficial microbes kickstarts the rhizophagy cycle early in plant development.
- Pairing microbes with a nutritional seed treatment ensures strong establishment.
Reduce Harmful Chemical Inputs
- Minimise fungicide and herbicide applications to preserve beneficial microbes.
- If chemicals are necessary, buffer their effects with humic or fulvic acids.
Ensure Sufficient Calcium for Cell Division
- Calcium is critical for root tip growth and cell division, making it essential for rhizophagy.
- Apply calcium through lime, gypsum, or liquid inject applications to support this process.
How Much Does the Rhizophagy Cycle Contribute to Plant Nutrition?
While research is ongoing, one study found that plants with active microbial interactions had 30% more nitrogen than sterile plants.
Some researchers suggest that 100% of plant nitrogen could theoretically be sourced through this system, eliminating the need for synthetic fertilisers. While that claim remains unverified, it is clear that the rhizophagy cycle plays a major role in nutrient efficiency and should be encouraged in all farming systems.
Final Thoughts: Unlocking the Potential of Rhizophagy
The rhizophagy cycle represents an exciting frontier in regenerative agriculture. By harnessing this natural process, farmers can:
- Reduce fertiliser costs
- Improve plant resilience
- Enhance nutrient uptake
- Increase soil microbial activity
If you’re an Australian farmer looking to integrate the rhizophagy cycle into your system, Agresol offers free consultations to help you transition to a more regenerative approach, You can sign up to a free consultation here!
