For years, scientists have recognized the phenomenon of allelopathy, by which one plant exudes a chemical that restricts competition from competing plants. What has changed recently is the technology available to isolate and identify these compounds. This was a difficult process only a few years ago, but it is a relatively easy process today. Once identified, it is possible to extract these compounds from natural sources and reproduce them for commercial use. One word of caution, however.
Many natural materials are toxic to humans.
The emphasis must be on isolating biologically active compounds from existing food-based materials that we already know are safe. Subsequent water stress causes wilt and eventual death. Researchers have worked with Xanthomonas for years and, finally, a commercial product is nearing the market. The unique qualities of such a product require certain techniques for successful application and control. To infect the Poa plants, these bacteria require fresh wounds through which they can enter.