The thrips are a common name for Thyroptera insects, which are small, slender and slightly flattened, and the plant-eating species among them are considered important agricultural pests.
In recent years, with the large-scale cultivation of citrus and the normalization of warm winters, the thrips have gradually become wild horses that have lost their reins instead of the docile foals of the year.
Thrips – maker of insect-derived peels
Thrips inside a citrus flower vessel
Due to the long fruit hanging period of citrus, the fruit surface is vulnerable to infringement and forms a peel fruit, which ultimately affects the selling price.
From the perspective of the genesis of the peel fruit, it contains both gray mold, scabs, ulcers, sand skin, vitiligo and other pathogenic flower skins, as well as insect-derived, medicinal and traumatic flower skins, and in the insect-derived peel fruits, more than half of them are caused by thrips.
Thrips mouthpiece
The thrips mouthpiece is typically asymmetrical, between the chewing mouthpiece and the sucking mouthpiece, and is a file suction mouthpiece.
They scrape the surface tissue of the plant through the mouthparts, causing direct damage, and then suck up the juice, like a comb with a straw.
Typical thrips
After the citrus fruit is patronized by the thrips, it will leave a silvery-white or gray-white ring scar, and because the thrips have the characteristics of good concealment, they move more around the fruit stem (at the shoulder), so the symptoms here are more obvious, extending to the waist and lower part of the fruit when severe.
Gray mold fruit
Thrips are often confused with the gray mold fruit we said earlier, in fact, it is still easier to distinguish, in the expansion of the fruit stage, when the two have a large number of symptoms, the scar of the thrips fruit is concave, and the scar bulge of the gray mold fruit is its main identification point.
The dominant species of citrus thrips vary month by month
In addition to flowers and fruits, thrips can also harm new shoots, which is more common in citrus autumn shoots. In addition, the types of thrips in the citrus flowering and fruiting stages and the autumn shoot stage are also quite different, such as the western flower thrips, The Japanese thrips, and the orange yellow thrips mainly feed on citrus flower utensils, the eight-section yellow thrips and the grass thrips like to harm the young fruits; the yellow-breasted thrips mainly harm the new shoots.
Citrus leaf thrips are harmful symptoms
The damaged leaves are initially greenish yellowish white spots, followed by gray-white stripes on both sides of the midrib, when the damage is more severe, the leaves are sagging, distorted and deformed due to the loss of expansion pressure, the leaves are yellowed, thinned and smaller, the new shoots are affected, the growth is slowed down, the internodes become shorter, and the self-shearing is carried out in advance.
Comprehensive prevention and control of citrus thrips
Agricultural control: Strengthening the work of clearing the garden can effectively reduce the base of insect sources in the following year and reduce the harm; plants that are susceptible to thrips such as legumes are not planted in or near citrus orchards.
Physical control: Thrips have the habit of pupating in the soil, weeding after spring, and covering the tree disc can block its continuous occurrence. Hanging the blue plate in the early stage of thrips can be booby-trapped, reducing the population density of the hazard, hanging 20 to 25 sheets per acre, sticking to the full / one month after paying attention to replacement, pay attention to the blue enticing board.
Pharmaceutical control: timely medication in key periods such as buds in spring and autumn, the initial flowering period, and the most of the time of xiehua. The medicine should be biased towards the use of good systemic suction, such as thiamethoxine, imidacloprid and so on. Before and after flowering, you can use ethyl polybactericide, ethyl spirochetes, zolazoleamide, thiamethoxam, etc., it is best to avoid medication during the flowering period, pay attention to spraying, spray evenly, thrips often hide in a hidden position, it is recommended that everyone use when counting the permeability of the agent, can increase the permeability of the agent, the hidden thrips a net.
This article is written and sorted by the agricultural assistant team, please be sure to indicate the source of the agricultural assistant, do not modify the content of the article, the modification must be investigated!