Palaemon

The genus Palaemon is part of the Palaemonidae family within the order Decapoda. While most species are marine or estuarine, specific species have adapted to freshwater environments, including irrigation systems and rice paddies. In these agro-ecosystems, they can shift their role from neutral organisms to active agricultural pests that damage young crops.

Palaemon primarily targets rice crops during the seedling stage. The soft tissues of newly emerged rice plants are highly attractive to these crustaceans. Their activity often leads to direct physiological and mechanical stress on the plants, which are sensitive during their early development phase in flooded fields.

The biological cycle of these crustaceans is heavily reliant on the presence of standing water. Within rice paddies, the species undergoes multiple larval stages, with populations increasing rapidly under favorable temperatures. The irrigation schedule directly influences their reproductive capacity and ability to colonize specific sections of the field.

Damage occurs when the crustaceans graze on the roots and the bases of young stems. This feeding behavior results in stunted growth, patchiness in the field, and in severe infestation scenarios, the complete failure of the crop stand. The level of damage is directly proportional to the density of the population and the depth of the water layer.

Effective protection measures focus on water management practices. Drainage of rice paddies at critical growth stages is the most efficient cultural control method, as it limits the habitat and mobility of the crustaceans. Additionally, monitoring water quality and managing vegetation in irrigation channels helps to reduce the survival rate of the population.