Article
Underground Insurance for Crops Under Pressure
by Dr Ash Martin PhD BSc(For)Hons
Nutrient and water limitations are two of the biggest constraints on crop yields. Arbuscular mycorrhizal fungi (AMF) can help crops cope with these stresses by improving nutrient uptake, water efficiency, and overall resilience. This review pulled together evidence from field and pot trials across cereals, legumes, and horticultural crops.
What they did: Researchers examined studies where crops were grown under nutrient or water stress, with and without VAM (Arbuscular Mycorrhizal Fungi, aka AM Fungi or AMF), to assess yield, nutrient efficiency, and stress tolerance.
What they found:
- AMF improved phosphorus and nitrogen uptake, especially in low‑fertility soils.
- Colonised plants used water more efficiently and maintained growth under drought.
- Yield benefits were strongest in maize, wheat, tomato, and capsicum under stress conditions.
- In high‑fertility soils or heavily disturbed systems, AMF benefits were reduced.
- Combining AMF with soil‑friendly practices (reduced tillage, cover crops, balanced fertilisation) enhanced effectiveness.
What this means for you:
- AMF can help stabilise yields when crops face nutrient or water stress.
- Benefits are most reliable in soils with moderate fertility or under challenging conditions.
- Supporting AMF through management practices increases their impact.
- Inoculants may be most valuable in stressed or degraded soils, rather than already fertile paddocks.
VAM are not a silver bullet, but under the right conditions they can make crops more resilient, efficient, and productive — especially when nutrients or water are limiting.
> Want to know if your soils are set up to handle stress? Run some of our VAM Wise for Soil, VAM Wise for Plants (Annuals) and VAM Wise for Plants (Perennials) tests to measure your VAM levels and guide your management decisions. Our Structure Wise test can also show you how much carbon is stored as glomalin. The results could be surprising!
Read the full article:
Posta & Duc (2019). Benefits of arbuscular mycorrhizal fungi application to crop production under water scarcity.
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