商品农药都为原液或原粉,必须按所需浓度加水稀释后才能喷布,原液(粉)稀释浓度的计算方法有以下几种,但一般多用倍数法。一、倍数法即稀释液的加水量为原液(粉)的倍数,一般多用重量倍数计算。1.水剂或乳剂加水公式加水倍数=原液重×所需稀释液倍数-原液重例如用乐果2000倍稀释液防治蚜虫, Commodity pesticides are the original liquid or raw powder, diluted with water at the required concentration before spraying, the original liquid (powder) dilution concentration calculation methods are the following, but the general multi-fold method. First, the multiple method that is diluted solution of water for the original liquid (powder) multiple, the general use of multiple weight calculation. 1. Liquid or emulsion water formula multiples of water = the original liquid weight × multiples of the required dilution - the liquid weight, such as dimethoate 2000 times dilution against aphids,