Grape tortrix

Systematic position. The grape tortrix (Argyrotaenia ljungiana) belongs to the order Lepidoptera, family Tortricidae. It is a highly adaptable polyphagous insect, recognized as a significant pest in both industrial orchards and viticulture regions across various continents.

Host plants. This pest has a wide host range, primarily affecting grapevines. However, it also thrives on various fruit-bearing trees including apple, pear, peach, and plum. It is frequently observed causing damage to berry bushes, certain shrubs, and a variety of ornamental plants.

Biology and life cycle. The species completes two to three generations per year, depending on local climate conditions. Larvae overwinter in the second or third instar inside protective cocoons located in bark crevices or among plant debris. In the spring, they emerge, resume feeding, and subsequently pupate before the emergence of adult moths.

Damage patterns and economic importance. Larvae feed on buds, young foliage, and developing blossoms, webbing them together into characteristic clusters. As fruit ripens, they bore into berries and fruits, causing deep cavities. This damage significantly reduces yield quality and promotes secondary infections such as grey mold (Botrytis).

Control measures. Integrated Pest Management (IPM) is essential for effective control. Cultural practices include cleaning tree trunks and removing infested debris. Monitoring involves the use of pheromone traps to time treatments correctly. Chemical control is implemented during periods of mass egg hatching using selective insecticides to minimize environmental impact.