Tea looper

The tea looper (Biston suppressarius) is a destructive pest belonging to the order Lepidoptera and the family Geometridae. This moth species is a significant threat to tea cultivation worldwide, capable of causing substantial economic damage if not managed through precise monitoring and timely intervention.

The primary host plant is the tea shrub (Camellia sinensis). The larvae are highly specialized feeders, consuming the succulent leaves and young shoots of the tea plant. Their presence in tea gardens often goes unnoticed until visible foliage loss occurs, highlighting the necessity for early detection programs.

The biological cycle of Biston suppressarius includes the egg, larval (caterpillar), pupal, and adult (moth) stages. Overwintering typically occurs in the pupal stage within the soil. As temperatures rise, adults emerge to mate and lay eggs on the host foliage. The larval stage is the most damaging phase, characterized by aggressive feeding behavior as the larvae progress through several molts.

The damage caused by the tea looper is direct and severe. The larvae consume the tea leaves, starting from the edges or creating holes, which quickly results in severe defoliation. A significant loss of leaf area reduces the plant's photosynthetic capacity, causing stunted growth, diminished harvest volume, and poor-quality leaf production during the growth flushes.

Integrated Pest Management (IPM) is the most effective approach for controlling this pest:

• Regular field scouting to detect early instar larvae before widespread damage occurs.
• Conservation of natural predators and parasitoids that feed on looper larvae.
• Application of environmentally friendly biopesticides, such as Bacillus thuringiensis, during early stages of infestation.
• Targeted use of specific insecticides, following economic injury level thresholds.
• Implementation of pruning practices that disrupt the pest's life cycle and remove harborages.