Mango growers in Hainan have begun to enter the flowering stage one after another, and the orchards that have been induced earlier have also entered the young fruit stage, and with the arrival of this period, the thrips, one of the five small pests of agriculture, have also begun to become active.
Early flowering in an orchard in a mango-producing area of Hainan Source: Grower
The young fruiting stage of the mango tree Source: Grower
At the beginning of Hainan, the harm of thrips was not so serious, but in recent years, because of the single use of drugs, mixed crops, changeable climate, etc., the resistance of thrips has been continuously enhanced, and the harm has also increased. At present, it has basically become one of the more headache pests in the mango producing areas of Hainan. Scientific understanding and control of thrips is the top priority of every mango grower.
Mango is harmed by thrips Source: Network
At present, there are many types of thrips that harm mangoes in China, of which tea yellow thrips are the most seriously harmful, followed by yellow-breasted thrips, and other species include: broad-shouldered reticulated thrips, Chinese tube thrips, red-banded thrips, brown thrips, Weidao thrips, light red wrinkle thrips, vinegar wrinkle thrips, etc. Today, Mangmeizi will take everyone to see and know this thrips.
Thrips have tenderness, with nymphs and adults sucking tissue juice on young shoots, young leaves, flower buds and small fruits, and the reproduction rate is fast, and it can reproduce about 20 generations per year, with overlapping generations.
In the shoot stage, the thrips move in clusters on the back of the young leaves, and the affected leaves have 2 or more longitudinal reddish-brown stripes on both sides of the main vein. In severe cases, the dorsal surface of the leaf is brown and dull, and the edges of the leaves are curled, even atrophied, and dried up in the later stages.
Thrips suck young leaves Source: Network
Thrips young leaf infestation symptoms (atrophy) Source: Network
Thrips young leaf pest symptoms (wilting) Source: Network
During the flowering and fruiting stages, thrips concentrate on endangering the inflorescence. Inflorescences that are generally infested with thrips will drip more water in the morning than those that are not harmed, and the water droplets are light black. When the insect population density is large, the inflorescence turns brown and dies; after flowering, the thrips will hide in the petals and calyxes, endangering the ovary, young fruits, etc., and finally causing the ovary to shrink and dry up.
Flowers and fruits turn brown and die after being harmed Source: Network
In the young fruit stage, the fruit surface will appear black brown or rusty brown needle-like dots, and even deformed fruit, and the skin tissue hyperplasia shows wood plugs, which is rusty brown rough. Seriously affects mango growth and fruit quality.
Young fruit victimization (bulging small bubbles, affecting fruit) Source: Network
Juvenile fruit victim (black-brown scar) Source: Network
1. Warm and dry weather is frequent. The premise of the thrips outbreak is that the climate is dry, and the occurrence of thrips on rainy days is generally not serious.
Recently affected by typhoons, Hainan, Guangdong, Guangxi and other mango producing areas have frequent rainfall, air humidity, so the number of thrips is not much, but do not take it lightly, once the rain stops, the weather turns sunny, thrips will break out.
2, cloudy days are harmful. Thrips have light avoidance and like to come out to eat in the morning and evening, and on cloudy days, thrips go out in large quantities to eat.
3. It can be migrated with the help of wind media. Thrips can be used to migrate from one region to another with the help of wind media.
4. The harm of orchards in different regions varies greatly. In some orchards in Hainan, we found that in the orchards adjacent to the melon and vegetable fields, thrips occurred early and the number of blooms was also large and long. Orchards far from melon fields suffer less.
5. Poorly managed orchards are more harmful. In addition, poor irrigation conditions lead to drought and lack of water in the soil, which is also conducive to the pupalization and feathering of thrips, which eventually occurs in large quantities; some orchards with uneven flowering provide sufficient food for thrips to occur, and there are many hidden places. These orchards are conducive to the occurrence of thrips in large numbers.
Tea Yellow Thrips Source: Web
The sooner the thrips are prevented, the better, and it is necessary to unify the prevention and control, strengthen orchard patrols, and prevent them in advance.
Agricultural control
✔ New orchards should choose to build gardens away from melon and vegetable fields to reduce the occurrence of thrips.
✔ Keep the orchard ventilated and transparent, reasonably densely planted, and adopt a round-headed happy canopy to ensure that the chamber between the rows and the body of the tree is transparent.
✔ Flower promotion neat. Do a good job in the early pruning, control and flowering and other series of work, strive for orchard mangoes to bloom neatly, reduce thrips hidden places, cut off rations, and achieve the purpose of reducing the density of insect populations.
✔ Increase soil moisture. Spraying some water between the rows can also effectively inhibit thrips pupae and feathering.
✔ Shake the flowers and pick the shoots. After the damaged petals turn brown and dry, it is recommended to shake the flowers every day to destroy the hidden feeding places of the thrips, which can also facilitate the spray control of everyone. It is also possible to remove the new shoots in time to reduce the source of insects.
Physical control
Booby traps can be performed near the inflorescence using a yellow or blue sticky board, a trap lamp, etc. However, according to the reaction of some farmers in Hainan, the effect of this method is not ideal.
chemical control
Thrips should preferably be sprayed after 3 p.m., and care should be taken to wet the back of the leaf and underground. Insist on inspecting the orchard every day, once the thrips are found to be used in time, and the thrips that occur in the early stage or fly into the orchard are completely eliminated, we must pay attention to the use of pesticides that are less toxic to the natural enemies of the thrips, and protect the control of natural enemies of the thrips.
Since the pupal stage of thrips is spent underground, it is necessary to pay attention to the combination of surface control and underground control, and the soil can be fully disinfected before the young trees are transplanted. Thrips have strong flight mobility, and it is recommended that the orchards of continuous pieces, unified medication can be used twice as effectively.
Medication is recommended
1. Neonicotinoid insecticides such as imidacloprid, alenopherolamine, and neonicotinoidine;
2. Flufenacillitrile, ethyl spiranteroid, ethyl polybactericide, avermectin, pyridocethrin, high efficiency cypermethrin, etc.
Man Meizi tips: Pay attention to alternate use, so as not to make thrips resistant.
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