Grub is the larvae of the scarab beetle, also known as the "white soil silkworm", this underground pest mainly harms peanuts, soybeans, vegetables and other crops, which will not only eat the seeds just sown, but also bite the young stems, roots, underground tubers of the seedlings, often lead to the lack of dead seedlings in crops, which is extremely harmful.
Grubs are hypertrophied, with a yellowish-brown head, a milky white body, and a curved C-shaped body, which is easily recognizable compared to other insects. This kind of underground pest in the spring and autumn two seasons of the most serious harm, when the plant withered yellow and dead, it will be transferred to the new plant to continue to harm, the pest serious plot, will cause a large area of plants to die in advance, or even harvest, so do a good job in the field grub control work is to ensure the stable yield of crops, one of the important measures.
<h1 class="pgc-h-arrow-right" data-track="5" > efficient control methods for grubs? </h1>
1. Sprinkle poisonous soil when sowing
Grubs are generally harmful in the soil, have a very strong concealment, when farmers see the leaves of the plant yellow before control, often the effect is very poor. Therefore, we can sprinkle poisonous soil before sowing or transplanting, which can effectively kill the grubs in the soil and effectively reduce the harm of grubs.
Specific operation method: We can use 5% octyl thion granules 3 kg mixed with fine soil 25 to 30 kg to make poisonous soil (or use 50% octyl thiophosphorus emulsion 300 ml, add 3 kg of water, spray on 30 kg of fine soil to mix into poisonous soil), and then evenly sprinkle the poisonous soil on the surface, and then plough, can effectively kill the grubs.
Note: Octyl thiophosphorus is sprinkled in the soil after a long residual period, has a touch killing and gastric toxic effect on grubs, its insecticidal spectrum is wide, in addition to the control of grubs, but also the treatment of other underground pests. Octyl thion is acidic and cannot be mixed with alkaline substances (grass and wood ash, quicklime).
Second, the drug mixture seeds
For grubs, it is better to prevent them early, so that the loss can be minimized. After the medicinal seed is mixed, it can effectively control grubs or other underground pests from nibbling on seeds, and will have a contact killing effect on grubs that come into contact with seeds.
Specific operation method: We can use 50% octylthion emulsion 100 ml, mix with 5 kg of water, and then mix 50 kg of seeds, and then sow again. Like peanuts, soybeans, wheat, sorghum, etc., can be controlled by means of medicinal seeds.
Third, prepare poisonous bait for booby traps
Whether it is sprinkling poisonous soil or medicinal seeds, more or less will cause pesticide residues, so what is a safer way to kill underground pests? Using poison bait to trap grubs is a very environmentally friendly method, and the effect of treating grubs is very good.
Specific operation method: We can sauté wheat bran, rice bran, bean cake powder until fragrant, and then add 100 grams of octylthion emulsion per 5 kg of bait (or 500 grams of 90% dimethoate crystals) to make poisonous bait, and then place it in the field, which can trap a variety of underground pests.
Special attention: grubs have negative phototropism, 8 to 9 o'clock in the evening will be unearthed for feeding and other activities, so we are best to place poisonous bait in the evening, so the prevention and control effect is better.
4. Winter plowing
Grubs are both afraid of heat and cold, moving into the deep soil when temperatures are greater than 23°C and when temperatures are cold in winter (below 5
°C) Larvae and adults overwinter in the soil.
Therefore, we can plough the soil in winter, let it dry on the surface, freeze to death, or be preyed upon by predators, which can effectively reduce the number of grubs in the soil.
Fifth, apply fully decomposed manure (farm manure)
Grubs tend to undeformed manure, so grubs prefer to live in plots containing uncorried manure, which attracts adults to lay eggs. In addition, if the farm manure is not completely decomposed, it is easy to carry germs and insect eggs, which will increase the risk of crop diseases and insect pests.
Farm manure should be treated harmlessly 2 months before application, and we can accumulate or cover the plastic film to allow it to ferment sufficiently (if it is too dry, it can be splashed with water and wet). When the farm manure is accumulated and fermented, the internal temperature will be more than 60 °C, which can effectively kill insect eggs or some germs, and the decomposed farm manure is more easily absorbed by crops.
Note: Farm manure will produce a large amount of organic matter during the decomposition process in the soil, and can also increase the ground temperature, providing an ideal living environment for grubs, which will cause serious harm to grubs.
Sixth, sprinkle green zombies or white zombies in the soil
Both green zombie and white zombie bacteria are pathogenic microorganisms that are effective in controlling grubs, in which green zombie bacteria dissolve the body wall, fat tissue and muscles of grubs, eventually causing the grubs to die. The spores produced by the white zombie fungus will grow hyphae in the insect after contact without grub contact, making the insect stiff and die.
In summary, grubs are recognized as difficult to control soil pests at home and abroad, which can harm a variety of crops, especially in recent years, peanuts, wheat, soybeans are seriously harmful, which will lead to crop lack of seedlings and ridges and even large deaths. For this kind of serious underground pests to focus on prevention, before sowing seeds can be used to spread poisonous soil, medicament and seed to prevent and kill grubs; when the field grubs have occurred in large quantities, then we can take poisonous bait to trap, or sprinkle biological insecticides to reduce the number of grubs. Usually, decomposing farm manure is applied in production, so that the number of underground pests will be relatively small.