Spider mite

The spider mite (Tetranychus) is a genus of plant-feeding mites in the Tetranychidae family, belonging to the order Trombidiformes. These microscopic pests are among the most destructive organisms in agriculture and horticulture, capable of causing widespread damage to a vast array of plant species globally.

As polyphagous pests, spider mites infest a wide variety of crops, including vegetables, fruits, ornamental flowers, and industrial crops. In agricultural settings, they are particularly problematic in greenhouse environments where high temperatures and low humidity create ideal conditions for rapid population growth and development.

The life cycle of the spider mite consists of the egg, larva, protonymph, deutonymph, and adult stages. Under optimal conditions, such as hot and dry weather, the entire life cycle can be completed in less than two weeks, allowing for multiple generations to occur within a single growing season, leading to sudden and massive outbreaks.

Damage is characterized by the presence of small, pale spots on the leaves, which eventually turn yellow and become necrotic. As the infestation progresses, the mites produce fine silk webbing, which covers the foliage. This causes a significant decrease in photosynthesis, leaf drop, stunted growth, and in severe cases, the death of the plant.

Integrated Pest Management (IPM) is essential for effective control. Cultural practices such as maintaining proper irrigation to increase humidity and removing host weeds are critical. When chemical intervention is necessary, the use of acaricides is common; however, rotating products with different modes of action is vital to prevent the development of pesticide resistance.

• Regular scouting for mite colonies on leaf undersides.
• Introduction of predatory mites for biological control.
• Disinfecting greenhouse structures between growing seasons.
• Application of selective acaricides upon reaching economic thresholds.