How to prevent and cure the latest green onion thrips?

Onion thrips supplement tobacco thrips, cotton thrips, etc., mainly harm onions, leeks, garlic, cucumbers, eggplant vegetables in vegetable fields, mainly distributed in Northeast China, Beijing, Hebei, Zhejiang, Jiangsu, Guizhou, Guangdong, Guangxi, Hainan, Taiwan, Shaanxi, Ningxia, Xinjiang, Xizang, Inner Mongolia and other provinces. Let's take a look at how to control onion thrips!

Onion thrips harm symptoms

Thrips of Allium fistulosum harm the heart leaf, tender bud and young leaf of the host by adults and nymph. The whole growth period of Allium fistulosum has its various insect body activity and feeding, which causes continuous silver-white spots on the leaf surface after injury of Allium fistulosum. Serious leaf distortion turns yellow and withers. From a distance, the field of Allium fistulosum is a "drought elephant", which seriously affects the quality and yield of Allium fistulosum.

Occurrence law of Thrips fischerii

Thrips of Allium fistulosum have 8~10 generations a year in North China. They overwinter as adults in leaf sheaths of overwintering Allium fistulosum, Allium fistulosum and Allium sativum, in soil crevices or in dead leaves and weeds, and emerge as adults when Allium fistulosum and Allium fistulosum turn green. The adults are active, they can spread by wind, they are afraid of strong light, they mainly feed in the morning and evening, they mostly feed in the shade and axils, they can carry out parthenogenesis, and their eggs are scattered in the host stem and leaf tissues. Nymph is not very active, mostly concentrated in the base of the leaf damage, a little bigger before scattered damage. The 2nd instar nymph burrows into the soil after maturity, molts into prepupal and pseudopupal stages, and finally emerges into adults. The first generation of thrips lasts for 20~35 days, and it will be prolonged when the temperature is low. The optimum conditions for its occurrence on Allium fistulosum were 23~28℃ and 40~70% RH. High temperature, high humidity and storm can inhibit its occurrence.

Control Measures of Thrips on Scallion

The main measures to control thrips are to clean the countryside, clear the field of onion and garlic and its surrounding weeds and residual leaves in early spring, burn them intensively, and eliminate the overwintering insect source. At the same time, fertilizer and water management should be strengthened, especially when the weather is dry, watering should be paid attention to, so as to promote the growth of plants and destroy the ecological environment conducive to the occurrence of onion thrips.

Chemical Control of Thrips fischerii

The chemical control of thrips on scallion can be carried out by spraying 3% acetamiprid EC 2000 times, 10% imidacloprid WP 1500 times, 4.5% beta-cypermethrin 1000 times and 99% mineral oil 150 times. Because scallion leaves are relatively smooth, foliar spreading agent or neutral washing powder can be added when spraying to increase adhesion and improve spraying effect.