Tea red spider mite

The tea red spider mite (Oligonychus coffeae) is a significant pest belonging to the family Tetranychidae within the order Trombidiformes. This tiny arachnid, known for its reddish-brown appearance, is a major threat to commercial tea and coffee plantations across tropical and subtropical regions worldwide.

The primary hosts for this pest include tea (Camellia sinensis), coffee (Coffea spp.), and various other tropical plants including cacao. The mites typically aggregate on the upper surface of the leaves, where they construct fine webs to protect their colonies and facilitate movement across the leaf tissue.

The life cycle consists of egg, larva, protonymph, deutonymph, and adult stages. Under favorable warm and dry conditions, the lifecycle duration is notably short, allowing the population to reach damaging levels in a matter of weeks. High temperatures accelerate their metabolic rates, leading to rapid outbreaks during dry seasons.

The mite feeds by piercing the epidermal cells and extracting sap, which leads to chlorophyll destruction. This damage appears as a "bronzing" or reddish-brown discoloration of the leaves. Severe infestations cause significant leaf drop, reducing the photosynthetic efficiency of the plant and leading to drastic losses in crop yield and quality.

Effective management strategies require an integrated pest management (IPM) approach to maintain populations below economic thresholds.

• Regular field monitoring to detect early signs of infestation.
• Application of selective acaricides when population density exceeds thresholds.
• Biological control through the encouragement of predatory mites and insects.
• Maintaining optimal soil moisture and irrigation levels to reduce mite susceptibility.
• Proper pruning to remove heavily infested foliage and improve airflow.