Tea Purple Mite

📖 Description

Tea Purple Mite (Calacarus carinatus), also called Purple Tea Mite or Carinate Mite, is an important microscopic mite pest of tea across the Indian subcontinent, particularly severe in the major tea-growing belts of Assam (Tinsukia, Dibrugarh, Sivasagar, Jorhat, Golaghat, Sonitpur — India’s largest tea-producing state with over 50% of national tea area), West Bengal (Darjeeling, Jalpaiguri, Cooch Behar, Alipurduar — the Dooars and Terai regions), Tamil Nadu (Nilgiris, Coimbatore, Theni, Anaimalai), Kerala (Idukki, Wayanad, Palakkad), Karnataka (Chikmagalur, Kodagu, Hassan), Tripura, Himachal Pradesh (Kangra) and the northeastern states where India is the world’s 2nd largest producer of tea (over 600,000 hectares cultivated, producing over 1.3 million tonnes annually — tea is a critical plantation crop for these regions, providing direct employment to over 1 million workers and contributing significantly to India’s agricultural exports). The pest is unusual among tea pests because (a) it is a tenuipalpid mite (false spider mite) — only 0.25-0.30 mm long, making it invisible to the naked eye and easily overlooked until leaf discoloration becomes obvious, (b) the pest feeds preferentially on MATURE leaves (not tender pluckable leaves) — distinguishing it from red spider mite which feeds on tender leaves — but the reduction in photosynthetic area of mature leaves directly reduces the plant’s ability to support new flush production, (c) the characteristic purplish-bronze discoloration of mature leaves is often misdiagnosed as nutrient deficiency (especially phosphorus or magnesium) or natural aging of leaves, (d) the pest has a very short life cycle (10-15 days) allowing rapid population buildup — 20-25 overlapping generations per year, (e) the pest has a narrow host range (essentially Camellia sinensis) — meaning that quarantining new plantings and planting away from infested sections can prevent establishment, and (f) the pest is most severe in plantations with inadequate shade regulation (too much shade favours mites), excessive use of broad-spectrum insecticides and sulphur sprays (which kill predatory mites), and in plantations with drought stress (stressed bushes are more susceptible). IPM with weekly mature leaf inspection, biological control (Amblyseius indicus predatory mite is highly effective, conservation of native predatory mites by avoiding broad-spectrum insecticides and sulphur sprays), neem-based sprays, wettable sulphur (but avoid use in hot weather), and need-based miticide rotation (systemic or translaminar miticides most effective — observe Minimum 7-14 days PHI for plucking) provides effective and sustainable control. The pest is a particular concern for Indian tea growers because the microscopic size and mature-leaf feeding habit make early detection difficult — by the time purplish-bronze discoloration is obvious across the section the mite population is already well-established and yield loss for the season may have occurred. The pest is most severe in the dry season (Mar-Jun in southern India, Nov-Feb in eastern India) when drought-stressed bushes are most susceptible. Climate change with more frequent and prolonged dry spells is increasing the severity of this pest across all major tea-growing regions of India.