Urea Mixed with Washing Powder?
Urea mixed with washing powder can prevent aphids? Yes, because the urea has the function of destroying the body chitin of aphid, and washing powder containing Sodium alkyl benzene sulfonate which is surfactant sodium can make aphid wax layer dissolved of body wall so that attached to it to 
form impermeable, airtight layer of film, resulting in aphid stomata blocked and die.
The using of urea mixed with washing powder has the features of high efficiency, no pollution, convenient and easy to top dressing. The applying method can refer to the following methods:
Preparation of washing powder, urea, water is 1: 3: 300.
Adding hot water to make washing powder dissolved, and then add urea and water, to stir well. Urea should be 0.5-0.7 kg per mu, neutral washing powder should be 125 grams and water should be 50 to 60 kg. Spray the solution after fully dissolved.
The mixed solution can control the aphids red spider, Pieris rapae and other pests of grain, cotton, vegetables, fruit trees and other crops. spraying once interval 7-8 days, continuous spray 3 times, the effect can up to 95%, and also can play a role of top dressing.
Note: the mixing should be sufficient, do not leave particles, because these particles easily lead to leaf burning. Spray to be uniform, must be sprayed on the aphids, otherwise it does not work.
Another method of inventing
A compound urine washing mixture is composed by raw materials of urea, synthetic washing powder or ammonium bicarbonate additive, potassium dihydrogen phosphate, thiourea. The weight ratio of urea: synthetic washing powder or ammonium bicarbonate additive: Dihydrogen phosphate Potassium: Thiourea = 4: 1: 0.5: 0.01. This compound urine is composed by urea, synthetic washing powder or ammonium bicarbonate additive, potassium dihydrogen phosphate and thiourea can be made into powder or solution (emulsion).
The present invention has the following features
Efficient, non-toxic, no residue, harmless 
to humans and animals, will not cause environmental pollution;
Able to kill cotton aphids, wheat midge and other pests;
Have a better effect on the crop of scab, white leaf disease;
Applicable to cotton, wheat, fruits, vegetables and so on;
Have good effect on the indoor mosquito elimination;
Production process is simple, low cost, the use is safe and convenient, with great social benefits;
Increase of production.
The technical features of the present invention
1, the K + Na + ion in the formula plays a role in regulating the K + -Na + balance in the metabolic process and enhancing the ability of the crop to resist pests and diseases;
2, urea, potassium dihydrogen phosphate for root application, have the function of foliar absorption and promote crop growth;
3, the surfactant has function to make the pest cortex dissolved, the body swelling and rupture;
4, to eliminate the drug resistance of pests.
The invention can provide a method for the preparation of a highly effective, non-toxic and non-residual pesticide compound urine-washing agent for killing cotton aphids, cotton bollworms, red spiders and mites.
Urea is not only a commonly used high quality fertilizer, but also good for Insecticide.
The article is quoted from: https://www.fert.cn/news/2017/10/12/100457372073.shtml
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