A high efficiency plasma activation system for large scale treatment of liquid including a liquid tank; a pump having an inlet fluidly connected to an outlet of the liquid tank; a self-suction mechanism having a liquid inlet fluidly connected to an outlet of the pump, an air inlet, and an outlet fluidly connected to an inlet of the liquid tank; and a plasma generator having a plasma discharge nozzle positioned adjacent to the air inlet of the self-suction mechanism and configured to discharge gas phase plasma into the air inlet of the self-suction mechanism and introduce micro/nano bubbles (MNBs) into a flow of liquid to be treated to where the MNBs collapse to agitate and impregnate the liquid with a gas, for highly efficient plasma activation of liquid on a large scale as a green and sustainable technology for disinfection in the food industry and agriculture.