Pc (percent concentration): indicates the percentage of active ingredients in the drug.
Ppm (parts per million): such as 1ppm (also written as ppm), is one in a million.
EC (effective concentration): A concentration that can prevent the control object,.......

The Central Meteorological Observatory is expected to have a cloudy and rainy weather in the southern part of the south of the Yangtze River and the northern part of southern China on the 23rd to 25th. The temperature will be lower than normal in the same period of the year. From 23 to 24, .......

First, choose the best treatment period medication. Try to choose to spray at the beginning of the disaster, when the population density and quantity are small, to increase the duration of acaricide and reduce the number of uses. The best control period on the f.......