Killer Quorum Mimic
To have any chance of success, bacteria attack plants en masse. Little pathogens determine that they have the numbers on their side via chemical quorum-sensing communications.
Plants understand quite well how bacteria operate. To thwart a mass assault, plants concoct and release chemicals that mimic those used by bacteria to signal each other that the time to attack has come.
A plant fires off its molecular mimic before bacteria have sufficient numbers to tackle their target. The microbes invade before they have enough troops, whereupon the plant picks them off.
