Primarily there are three main types of agricultural industries that uses the dye. They are the crop protection industry, fertilizer industry and the seed dressing industry. The purpose of the dye used here is for colouring of agricultural chemicals or in the identification process of agricultural chemicals. The basic selection criteria depends upon the following:-

• Colour strength of the particular dye
• Dye colour
• Colour stability
• compatibility of the dye with the particular agent

Let's see each of the application in detail.

Fertilizers are often added with colouring to differentiate between qualities and to avoid any type of errors in application. Fertilizers are also coloured for purely marketing purposes. Usually water based pigment is often used in the diluted form and is sprayed onto the fertilizer or sometimes incorporated into a melt.

Use of colourants in crop protection agents of the type insecticide and fungicides helps to clearly demarcate treated areas from the untreated ones. In addition, the dye stuffs also help in promoting safety in the handling operations.

Colouring of pesticides or herbicides is generally done by mixing chromatic pigments with dry powder formulations of the agents. Milori blue is a very popular pigment, that goes well with viticultural fungicides, other categories of pigments include lithol rubine, heliogen blue etc., Dyes used in the crop protection industry are Solvent dyes, Acid dyes or Basic dyes the better alternative.

The main objective of colouring the seed dressings is used for marking and a warning reference. To avoid any sort of confusion and making sure that it does not end up being used as fodder. The most important colourant used here is red with typical concentrations of 600 ppm.