Rice transplanter-mounted liquid reagent application device, and method of applying liquid reagent during rice planting using same

A device for distributing and discharging a liquid reagent provided. The device comprise a tank (10) storing the liquid reagent; a pump (12) draws the liquid reagent from the tank (10); a pipeline connected to the pump (12) to carry the liquid reagent drawn by the pump (12); a distribution unit (20) connected to the pipeline (16) to distribute and discharge the liquid reagent carried by the pipeline (16); and a mechanism that receives the liquid reagent carried by the pipeline (14) and captures air contained in the received liquid reagent. A method of applying a liquid reagent to control pests, fungi, and/or weeds during rice planting using the device for distributing and discharging a liquid reagent. The method comprising: applying the liquid reagent though the distribution unit (20) and into one or more spaces between a plurality of hilling in which seeding are planted.