Color disk kits – Color disk test kits are available for a wide range of chemical tests. In a typical set-up, the user adds a powder packet or a few drops of a liquid reagent to a water sample in a reusable plastic tube. The user then places the sample tube in a small plastic viewing box. This viewing box contains a plastic disk with a color gradient printed on it. The user rotates the color disk to find the part that best matches the color of the sample, and then reads the concentration of the chemical from the disk. Color disk kits typically have multiple steps and often include prescribed wait times, so they’re a little more complicated and costly, but generally more accurate.
There are a number of color-strip tests for the more common chemicals, e.g. organophosphates, atrazine... but other than the specific pesticides you would like to quantify, of course it is important to consider accuracy/precision required for reporting, of which field kits will likely not be able to match the certified LC or GC methods. Nevertheless, there are kits:
Abraxis has a wide range of ELISA assays: https://www.abraxiskits.com/products/pesticides/
Neogen has a color disk kit for quite a few classes: https://foodsafety.neogen.com/en/agri-screen-tickets