Tea leaf miner

Systematic position. The species Ketumala thea belongs to the order Lepidoptera and the family Gracillariidae (leaf blotch miner moths). It is a specialized pest primarily associated with the tea plant, displaying unique behavioral patterns related to its larval development within leaf tissues.

Host plants and damage. The main host plant for Ketumala thea is the tea plant (Camellia sinensis). The pest is particularly detrimental in regions where tea is cultivated on a commercial scale, as the larvae feed exclusively on the internal layers of the leaves, directly interfering with the plant's metabolic processes.

Biology and life cycle. The life cycle consists of four distinct stages: egg, larva, pupa, and adult moth. The adults are nocturnal and small in size. Larvae are the primary damaging stage, as they tunnel through the leaf epidermis to create mines, which act as their protection and primary food source throughout their developmental stages.

Symptoms and economic impact. The visual evidence of infestation includes irregular brownish or translucent mines on the leaf surface. As the infestation progresses, leaves become brittle, dry out, and drop prematurely. This extensive tissue damage leads to significant yield losses and reduces the overall vigor of the tea bushes, resulting in decreased productivity.

Protection and control measures. Management of Ketumala thea requires a multifaceted strategy including

• monitoring using pheromone traps;
• pruning of affected foliage;
• encouragement of natural predators;
• targeted application of insecticides when thresholds are exceeded.