Diversisporales

It is essential to clarify that Diversisporales are not a plant disease. Instead, they are an order of fungi belonging to the phylum Glomeromycota, known for forming arbuscular mycorrhizae (AM). Far from being pathogens, these fungi are beneficial symbionts that establish a vital relationship with the roots of the vast majority of vascular plants on Earth.

The biological nature of this interaction is a mutualistic symbiosis. The fungi extend their hyphal networks far beyond the depletion zone of the root, allowing the host plant to access nutrients like phosphorus, nitrogen, and micronutrients that would otherwise be unavailable. This enhances the plant's growth, stress tolerance, and overall yield potential in various agricultural systems.

Virtually all agricultural crops, including cereals, legumes, and orchard fruits, benefit from the presence of Diversisporales. The primary exception is the Brassicaceae family (e.g., canola, mustard, cabbage), which does not form this type of mycorrhizal association. Therefore, no control measures are required, as these fungi are assets rather than threats to productivity.

There are no symptoms of disease or damage associated with these fungi. Instead, the colonization is internal and beneficial. Under a microscope, one can observe the characteristic arbuscules, which serve as the exchange interface for nutrients between the fungus and the plant host cells, indicating a healthy and robust root system.

To promote the presence and development of these beneficial organisms, agricultural practices should focus on soil health management. Excessive reliance on synthetic fungicides and high-phosphorus fertilizers can inhibit mycorrhizal colonization. Management strategies include:

• Reducing tillage to prevent the disruption of the fungal mycelial network.
• Using cover crops to ensure a continuous supply of host roots.
• Applying organic matter to improve soil structure and microbial biodiversity.
• Avoiding over-application of chemicals that could negatively affect soil microbiota.