In Jinxiang County, the hometown of garlic, garlic planting in 2019 is nearing the end, after the National Day No. 4, No. 5 since the planting of garlic, garlic seedlings have been about 10 cm in height, the third leaf is also withdrawn, from a distance, a green, bright green garlic leaves and reflective mulch film, forming a unique landscape of garlic township.
Freshly grown garlic seedlings
After planting garlic, the temperature is suitable for the growth of garlic seedlings, and the natural temperature in the field is high. Under such temperature conditions, garlic pests and diseases also occur, and garlic planted earlier has the harm of leafminer flies on garlic seedlings. Garlic leafminer can cause the middle of the garlic leaf to be mothed by the leafminer larvae, from the appearance, there are some white messy symbols appear, can not see the insects, think it is out of thin air, so it is named "ghost drawing symbol". Leafminer infested garlic seedlings, the leaves will be endangered, affecting the photosynthesis of garlic. The leaves are yellowish, and the newly ejected leaves have obvious bite marks after they grow out. Garlic seedlings also appear yellow leaves, slow growth, leafminer flies further endanger the false stem of garlic, garlic leafminer fly occurs, will cause garlic seedlings to grow slowly, serious leaves yellow, the affected parts of the rot, to garlic production bring great harm. Leafminer flies are different from garlic maggots, which mainly harm the roots of garlic, and leafminers harm the upper parts of the ground of garlic. Small leafminer flies can harm a variety of crops, such as beans, cucumbers and other crops. Why is there such a big harm?
"Ghost drawing symbol" on cucumber leaf
1, garlic leafminer fly is affected by the temperature is relatively large, when the temperature drops more, the weather is cold, not suitable for the growth and development of garlic leafminer fly, if there is a leafminer fly, it can only wait until the spring of the second year to occur. In the autumn of 2019, after the National Day, a cold air, so that the temperature of more than 30 degrees to a suitable temperature, 25 degrees or so, this temperature is also suitable for the growth and reproduction of garlic leafminer flies, therefore, on the garlic seedlings appear maggot-like small things, it is not garlic maggots but leafminer larvae, when the temperature is too low, it is not suitable for it to continue to breed harm, so it turns into pupae, overwintering in the soil around the affected plants.
Garlic yellow leaves
2, the severity of garlic leafminer fly occurrence has a certain relationship with the pre-stubble crop. After the actual planting, it was found that the former stubble planted corn, cotton and other crops, the lower stubble planted garlic, rarely found the harm of garlic leafminer flies. Instead, in the field where beans and melons are planted, garlic is planted, and the chance of garlic leafminers harming garlic seedlings increases. The reason is that the stubble planted beans, cucumbers and other vegetables, at a high temperature, suitable for leafminer flies to cause harm, control of leafminer flies is not good, after the harvest of the stubble crop, the remaining leafminer larvae after pupatation fell into the soil, after feathering in the appropriate period, continue to lay eggs to harm crops, with careful observation, garlic leafminer fly can be planted after garlic planting, before the winter period of time to carry out harm, winter stop harm, after April of the 2nd year, the temperature gradually rises. It also provides opportunities for harm to the garlic leafminer fly.
3, the use of organic fertilizer, not fully decomposed, it is easy to attract leafminer flies, as well as garlic maggot flies and other pests to lay eggs, harmful.
4, garlic leafminer fly control method, known stubble crop residues, will bring certain side effects to the stubble crops, therefore, and the front stubble crops in a timely manner to clean up, in the stubble crop planting during the emergence of leafminer flies hazards, should be timely spray pesticide control, minimize the factors that pose a threat to the stubble crops, commonly used agents generally choose high efficiency and low toxicity, low residue pesticides. It can be sprayed with 300 times liquid of Thuiensis bacillus + 1500 times of fly-killing amine + 1000 times of high-efficiency permethrin. After garlic planting, a compound preparation of Bacillus thuringiensis + paracynide is added to the herbicide used. Spray the ground inside the garlic furrow before covering the mulch, then cover the mulch. For the prevention of leafminer flies of garlic, garlic maggots have a certain anti-effect. Or flush octyl thion 800 to 1000 ml per acre of land.