Text/Native Life Gardening
Green onion, is a lily vegetable crop, it is a common and prefer a seasoning, spiced vegetables. There are many types of varieties of green onions, the growth adaptability is wider, and it has certain nutritional value and edible and medicinal value. Therefore, the planting area every year is very large, especially the green onion has a cold effect, which is deeply loved by friends in the north.
There are more diseases and insect pests of green onions, and the probability of occurrence is relatively common, and it occurs to varying degrees every year, which is the main reason for restricting the quality of our production.
The thrips are pests of the thripsidae of the order Lycaenidae, which occur and are distributed throughout the country, endangering a variety of crops and vegetables, and green onions are one of them. Adult thrips are yellowish-white or dark brown, with a body length of about 1 mm, a file suction mouthpart, and thin and long wings, pale yellow.
The onion thrips suck the juice of the leaves and leaf sheaths with its unique mouthparts, and the injured parts form yellow-white spots, and a large number of spots densely form large long spots, which can cause the leaves to curl and deform.
Occurrence condition
Onion thrips occur in about 10 generations per year, and the severity of the disease varies from region to region. When the temperature is below 25 degrees Celsius and the relative humidity of the air is below 60%, it is beneficial for the occurrence of thrips. High temperature and high humidity, but not conducive to its harm, so every year in the spring of April to May, autumn in October and November is the concentrated occurrence of onion thrips, growers should do a good job of prevention in advance. Adult shallot thrips are afraid of light and eat heavily in the morning or at night, so the amount of insects on the back of the onion leaves is concentrated.
Prevention and control measures
1, agricultural control. The soil in the field is deeply ploughed in time, and the weeds in the field are cleaned, and the watering should be timely to alleviate the drought and increase the humidity in the high temperature season. Organic fertilizer should be thoroughly decomposed, reduce the hiding place of larvae, and increase the application of phosphorus and potassium fertilizer at the seedling stage to promote the robustness of the plant and improve the resistance of the seedlings.
2, chemical control. When the larvae are in full bloom, it can be sprayed with water such as octylthion, imidacloprid, acetamiprid, matrine water agent, etc., generally once a week, and can be effectively controlled with 2-3 times.
Leafminer onion, widely distributed in areas where allium crops are present. Such as garlic, leeks, onions can be affected by the onion spot leafminer fly, of which green onions and leeks are the most seriously affected.
Leafminer fly larvae moth the leaf flesh inside the leaflet, forming an irregular white "channel" filled with their feces, showing a dark brown color, and in severe cases the passage is contiguous, forming spots. Leafminer flies harm the leaves of allium, seriously affect the photosynthesis of green onions, causing the leaves of green onions to gradually turn yellow and wilt.
Leafminer flies are particularly widely distributed, with 5-15 generations occurring per year, and the hazards vary from region to region. In the northern winter, when the temperature is low or the summer temperature exceeds 35 degrees Celsius, it can be seen that it overwinters and overwinters, and the rest of the time can be endangered. From nursery shallots to mid- to late-growth shallots, they can be affected by them. In particular, July and August are in full bloom, and the most serious harm is a major pest of scallion production reduction.
1, agricultural control. Timely clean up weeds and debris in the field to reduce the source of insects. Leafminer onion-spotted leafminers feed on lily crops in a targeted manner, which means that it only harms lily crops, so, based on this property, we can alternate crop rotations with non-lily crops. The soil in the field is turned deep before the seedlings are colonized, and the amount of watering is increased during the peak period and the tillage is timely.
2, chemical control. For shed planting, you can choose cyano-polyester smoke shed, or use avermectin, methamovectin benzoate, fly-killing powder and other water spray control, generally once a week, continuous use 2-3 times.
In addition, yellow sticky boards can be hung in the field to trap adult insects, or use natural enemies such as Ji Xiaofeng for control. Leafminer larvae should be used well at a young age, such as larvae in the peak period from May to September, and the best effect is used when the worm path is less than 2 cm; when the adult insect is controlled, it should be carried out when its activity is large, such as morning or evening medication, the best effect!.
Well, for more pollution-free planting techniques, please pay attention to our "Pollution-free and High-Yield Cultivation Technology Explanation" column, where we will update the most practical planting techniques and experiences at any time. Thank you!