Tea looper

Systematic position: The tea looper (Ectropis obliqua) belongs to the order Lepidoptera and the family Geometridae. It is a highly destructive pest, widely recognized in major tea-producing countries for its significant impact on crop yield and leaf quality.

Host plants and damage: The species primarily attacks the tea plant (Camellia sinensis). The larvae are voracious feeders, consuming the leaf tissue and leaving behind only the midribs or causing complete defoliation. This intensive feeding reduces the plant's photosynthetic capacity, causing stunted growth and substantial reduction in tea production.

Biology and life cycle: The life cycle comprises four stages: egg, larva, pupa, and adult. Adult moths are primarily nocturnal and cryptic. Females deposit eggs in clusters on twigs or the underside of leaves. The larvae, which are known for their distinct looping movement, go through several instars. The pupal stage typically takes place in the soil or leaf litter beneath the tea bushes.

Economic impact: Due to its rapid reproductive rate and multiple generations per year, Ectropis obliqua can reach epidemic levels very quickly. Damage to tea plantations is not only quantitative, leading to yield loss, but also qualitative, as heavy infestations affect the chemical composition and the overall quality of the processed tea leaves.

Control measures: Integrated Pest Management (IPM) is essential for effective control. Key strategies include:

• Cultural control, such as regular weeding and cleaning the base of the bushes to expose pupae.
• Biological control by encouraging natural parasitoids and predators.
• Use of microbial pesticides, specifically those containing entomopathogenic fungi or bacteria.
• Judicious application of selective insecticides to keep populations below the economic injury level while preserving beneficial insects.