Stone-sulfur mixture is the simplest medicine. Mix it yourself.
Triazotin is widely used in citrus, and it is also the most cost-effective agent at present. At present, the "Dongzhou" brand of triadimefon in China is relatively stable, and its efficacy can reach 30 days, which is not harmful to citrus. It can be used alone or mixed with other pesticides such as abamectin and propargite, and is the first choice for killing mites in citrus orchards.
Spirodiclofen is the most advanced drug at present, which has low toxicity and is very friendly to the environment, and it is also the drug with the longest action time at present. It lasts for 60 days, and it is cleaner after application. In the southern citrus orchard, this product has great potential to replace triazole tin. The representative variety is propafenone imported by Bayer Company in Germany, and some manufacturers in Shandong, Henan, Guangdong and other places in China also produce it. However, because it is a Bayer patented product, domestic manufacturers have no certificates. In addition, this product also has its own weaknesses. For example, this product is ineffective and expensive for male adult mites (100g retail price is about 50~70 yuan). However, due to its unique characteristics, it is strongly recommended to use.
Other drugs, such as abamectin+mirex, hexythiazox, abamectin, etc. It can also be used because of acaricidal spectrum, price and safety, but it is not the first choice. If you want to know more, collect information yourself.
Shit, I read your question wrong. It turned out that it killed scale insects, not mites. . . But since you grow citrus, I believe the recommended acaricide is useful to you. Keep it.
The two most important periods for controlling scale insects are hibernation period and wandering period.
In the hibernation period, that is, early spring, clean the garden, remove all weeds in the garden, coat the trunk with sulfur mixture and quicklime, and trim it.
Drugs for scale insects are common and generally toxic, so it is generally not recommended to kill scale insects before they form. Instead, it is suggested that you use the medicine in the early spring when the scale of the scale insects has not formed (called wandering period, during which the scale insects can crawl on the trunk without secreting wax, and the drug resistance is almost zero at this time), and the ingredients are simple, such as high work, high chlorine, bifenthrin, dichlorvos and oxygen. This is the most effective way to control scale insects.
However, if we miss these two periods and the shell has formed, it will be a little troublesome to use drugs, because at this time, we need strong intermediate drugs and strong systemic drugs, which will easily cause drug residues. Methimazole phosphorus (with strong wax melting effect) is the first choice, followed by omethoate and dichlorvos (with strong systemic effect), but the formulas of methimazole phosphorus+buprofezin copper and methimazole phosphorus+omethoate are generally recommended.