In recent years, due to various factors affecting the cultivation and production of garlic, the phenomenon of yellowing has become more prominent, causing adverse effects such as reduced yield and quality in garlic production. At present, it is a period of winter planting garlic. In previous years, many farmers have encountered garlic yellowing. What is the reason for this?

In general, garlic yellowing is mainly caused by improper management of fertilizer and water, soil acidification, and other reasons. In fact, the yellowing of garlic is more likely caused by pests and diseases, especially the root knot nematode disease, which has been particularly severe in recent years. Root knot nematode disease is caused by nematodes infecting crops. There are many types of crops that are affected by root knot nematodes. If trees, melons, eggplants, beans, and other crops are affected by nematodes, garlic is not excluded.

When the second instar larvae of garlic root knot nematodes harm garlic, they will puncture the tender parts (root tips) of fibrous roots through sharp mouth needles. The root knot will hinder the absorption of nutrients and water by the root system, and the growth of the root system is hindered, often resulting in the phenomenon of not growing new roots. However, the symptoms of aboveground diseased plants are not obvious in the early stages of being affected, but as the disease progresses, they will gradually show weak growth, pale yellow green leaves, and scattered leaves, similar to the symptoms of water and fertilizer deficiency. As the disease progresses, the diseased plant gradually yellows, wilts, and even withers and dies.

According to experts, in recent years, with the adjustment and upgrading of China's agricultural structure, coupled with factors such as traditional planting patterns and limited arable land area, the multiple cropping index of crops has generally been high. Some plots of vegetables, melons, and other nematodes have been planted on host plants for a long time, and the root knot nematode disease is seriously harmful, leaving a lot of insect sources in the soil. Garlic is often rotated or intercropped with these host plants, This has led to the occurrence of garlic root knot nematode disease, especially in greenhouses, greenhouses, and protected areas.

From this, it can be seen that preventing garlic yellowing cannot be achieved without the prevention and control of garlic root knot nematodes. Experts say that the prevention and control of root knot nematodes should focus on prevention rather than treatment, with prevention as the main focus. Preventive measures can be taken through agricultural and physical control methods, while controlling root knot nematodes requires the combination of chemical agents to achieve the best control effect. In terms of pesticide selection, farmers can choose Yinghui thread killing agent. It is understood that Yinghui thread killing agents include Ligen Sha, Yinghui Kuaishian, Tiandi Xian, and other products. For different growth stages of garlic, two dosage forms have been introduced: granular and aqueous. They can be used at different growth stages of garlic, and their prevention effects are quite outstanding. Farmers can use Yinghui nematicide granules for ditch application, hole application, or whole field spraying before transplanting garlic, with a duration of up to 2-3 months; If garlic is damaged by root nematodes during its growth period, Yinghui nematicide can be mixed with water to irrigate the roots and sprayed.