Perch

The systematic position of the genus Perca belongs to the order Perciformes, family Percidae. In the context of agronomy and intensive greenhouse operations, perch is not a traditional crop pest, but it is recognized as a significant biological risk factor in aquaponic systems.

In closed-loop systems where vegetable crops are grown on a nutrient solution circulating through fish tanks, perch can cause mechanical damage to plant root systems. Their predatory nature and activity in the bottom layers of the water often lead to root erosion, which creates pathways for the entry of various pathogenic microorganisms.

The biology and development cycle of this organism include spawning stages that require specific temperature conditions. In industrial recirculating aquaculture systems (RAS), perch are characterized by a high metabolic rate, which alters the chemical composition of the plant nutrient solution, requiring constant monitoring of nitrogen compound levels.

The nature of the damage is manifested by the nibbling of fine root hairs and the disruption of the root ball integrity, which reduces the productivity of greenhouse crops. The detrimental effect appears as stunted vegetation, leaf chlorosis due to root stress, and potential plant contamination with fungal infections carried by the fish.

Protection measures in agro-industrial complexes include:

• Installation of fine-mesh filters and protective screens between the fish culture area and the hydroponic section.
• Using substrates that prevent direct access of fish to the roots.
• Regular control of water quality and fish stocking density.
• Application of specialized biofilters to neutralize metabolic waste products that may inhibit plant growth.