A long time ago, on a job interview with an agricultural chemical company, I was told that the only crops that herbicides, fungicides, and insecticides were developed for were those that were planted in huge quantities like wheat and corn. The reason given was that even crops like peppermint and spearmint, even though significant, did not make significant money to warrant research for a research program.

The only hope for such research would lie in an academically oriented proposal in a state agricultural school. Unfortunately, funding for such research is rapidly disappearing. Even funding for highly useful research is falling off for those programs where a quick and large benefit cannot be realized. I've seen this throughout all of the physical sciences I've encountered since the 80s, and it keeps getting worse all the time.

No one wants to fund a skunk works these days, and it is getting harder to do it by oneself.