Lyngbya aerugineocaerulea

Lyngbya aerugineocaerulea is a filamentous cyanobacterium identified as a significant phytopathogenic agent, particularly within aquaculture and flooded crop systems such as rice paddies. It forms expansive, slimy mats that interfere with normal plant physiological functions.

The causative mechanism of this condition involves the formation of dense biofilm layers that physically smother emerging seedlings. This prevents essential gas exchange and blocks sunlight, which directly disrupts the photosynthetic capacity of the young plants and leads to severe growth stagnation.

Crops most susceptible to this organism include rice and other semi-aquatic vegetation grown in stagnant or slow-moving water. Symptoms include the emergence of visible, dark-colored mats that coat the soil surface and the lower stem areas of plants, often emitting a distinct odor as the organic matter begins to decay.

Development and spread are primarily driven by environmental factors such as high water temperatures, nutrient enrichment (specifically nitrogen and phosphorus loading), and lack of water flow. These conditions facilitate rapid colonization and the expansion of the cyanobacterial mats across the agricultural field.

Management and prevention strategies focus on modifying the growth environment:

• Maintaining adequate water circulation to prevent stagnation.
• Strict monitoring and regulation of fertilizer application to prevent nutrient runoff.
• Regular mechanical monitoring and removal of algae accumulation.
• Implementation of biological or chemical algicides when necessary to reduce the pathogen population.