The mushrooms were observed to inhibit other fungal growth around them. The active chemical was extracted and identified. The companies who did the development modified these natural compounds slightly so they would not photo decompose too quickly. Now both Zeneca and BASF Companies manufacture these novel compounds for commercial use. Perhaps the best news to growers is that this new group of fungicides controls all four of the major groups of fungi that attack grapes.
Most fungicides control only one or two groups of plant pathogenic fungi.
The Strobilurin compounds have a new and novel mode of action for control of plant pathogenic fungi. They inhibit the electron transport system in plant pathogens, but not in other living entities. They are very effective and very selective. The new chemicals can and should be used in a resistance management program. In other words, these fungicides should be used in an alternation program with other chemicals in a seasonal disease control program.