Onion thrips

Damage characteristics: It mainly damages Allium cepa (onion), Welsh onion, water onion, scallion, garlic chives, garlic and other Liliaceae vegetables, as well as tobacco, cotton, etc. Adults and nymphs use their piercing-sucking mouthparts to damage the heart leaves and tender buds of host plants, causing many long yellow-white or gray-white streaks to form on the host leaves, and the leaves become twisted and deformed.

Morphological characteristics: Adults are 1.2-1.4 mm long, light yellowish-brown, with yellow-white wings.

Life habits: Onion thrips occurs 6-10 generations a year in North China, with the most severe damage in April-May. Adults are very active and can spread with the wind, and feeding is intense in the morning and evening or on cloudy days. Onion thrips is prone to occur when the temperature is around 25°C and the relative humidity is below 60%. Storms can reduce its population.

Control methods: (1) Remove field weeds and residual plant debris and fallen leaves, burn them in a centralized manner or bury them deeply to eliminate overwintering insects. (2) Strengthen fertilizer and water management to promote vigorous plant growth. (3) Chemical control. Choose 80% dichlorvos emulsifiable concentrate at 1000 times dilution, or 25% fenitrothion emulsifiable concentrate at 1000 times dilution, or 50% phoxim emulsifiable concentrate at 1000 times dilution, or 20% fenvalerate emulsifiable concentrate at 3000-4000 times dilution, or 4.5% beta-cypermethrin at 3000-3500 times dilution, etc., for spraying.