Glover spider mite

Systematic position: The Glover spider mite (Tetranychus gloveri) belongs to the class Arachnida, order Trombidiformes, and family Tetranychidae. It is a highly specialized herbivorous pest that feeds on the sap of various host plants worldwide.

Crops damaged: This species is polyphagous, attacking a wide range of agricultural and horticultural crops. Major hosts include vegetables, cotton, various legumes, and ornamental plants. It thrives particularly well in greenhouses where conditions are stable throughout the year.

Biology and life cycle: The life cycle involves the egg, larva, protonymph, deutonymph, and adult stages. The speed of development is highly dependent on ambient temperature; under hot and dry conditions, the life cycle is significantly shortened, allowing for numerous overlapping generations that can quickly overwhelm a plant.

Damage and economic importance: The mites pierce the plant cells, typically on the underside of leaves, causing chlorosis, stunting, and reduced yield. The formation of webbing is a characteristic symptom of heavy infestation, which serves as a protective structure for the mite colony and significantly reduces the plant's photosynthetic capacity.

Control measures: Management of Tetranychus gloveri requires an integrated pest management (IPM) strategy. Key methods include:

• maintaining adequate plant hydration to discourage mite activity;
• sanitation practices to eliminate overwintering sites;
• introduction of natural predators such as predatory mites (Phytoseiidae);
• the judicial use of acaricides when economic thresholds are exceeded.