How to control thrips in scallion fields? A full analysis of control methods

Thrips are one of the important pests damaging Welsh onions. Adult and nymph thrips use their rasping-sucking mouthparts to damage the plant's heart leaves, tender leaves and tender buds, sucking sap, causing many fine, densely packed, continuous silvery-white streaks to form on the leaves, with leaf tips drying up, and in severe cases making the leaves unfit for consumption, greatly affecting the yield and quality of Welsh onions.

The thrips damaging Welsh onions mainly include onion thrips, tobacco thrips and rice thrips, etc. They often occur mixed together, and their peak damage period is from May to September. Thrips are tiny, ranging from light yellow to dark brown, and this insect can produce multiple generations per year. Adults are afraid of sunlight, and during the day they mostly damage the leaf axils or shaded parts of the leaves, and only in the morning, at night or on cloudy days do they move about and feed on the leaf surface. High temperature and high humidity favor their occurrence, reproduction and damage, while drought with no rain or failure to water in time leads to rampant damage. Control methods:

1. After harvesting Welsh onions, promptly remove residual plant debris, fallen leaves and weeds in the field and around it, and dispose of them properly, which can reduce overwintering sources of the pest.

2. Drought favors the occurrence and damage of this pest, so timely watering can promote vigorous plant growth, improve insect resistance, prevent the spread of the pest and reduce damage.

3. During the peak occurrence period of adults and nymphs, you can use 10% imidacloprid wettable powder at 2500 times dilution, 2.5% Huifeng fenpropathrin emulsifiable concentrate at 2000 times dilution, etc. for control, with good results.