Interesting!
To evaluate a new product or a new technical solution is always complicated, takes time and costs money.
If marketing research is new to you and you do not have much experience in this, you should absolutely seek advice.
It is a bit difficult to answer your question directly, as I do not know your product status at present. What do you expect to get back as answers after your contact?
Points:
Market research: Wich market do you go for. How large is this market. Suppliers and producers for this market? Large end users for product tests?
Product status, technically and price. Which products do you compete with? Do your product have advantages over similar products? Price, maintenance, operational cost advantages? Is it unique, protected by patent or other? Has it proved itself under longtime operation?
Please also remember that end users both in agriculture and for industrial purposes are conserative, and do not easily change to new consepts.
Are you sure your product does not have competitors with near or equal technical solutions?
And no, I am not a direct expert on irrigation, which covers a lot of different needs and solutions, where I know some. I have however a fair kbowledge of industrial solutions/diaphragm vales.
Good Luck!