PROBLEM TO BE SOLVED: To provide a plant cultivation system, a plant cultivation device and a method for producing all types of plants such as leaf vegetables, fruit vegetables, head formation vegetables, and beans by circulating a single quality nutritious liquid without causing a replant failure throughout a year simultaneously.SOLUTION: A single quality nutritious liquid flows at a prescribed speed inside cultivation tanks that independently support a plant. A modified air made from air so that the air becomes adequate state to make a dissolved oxygen concentration of the single quality nutritious liquid in the cultivation tanks to a prescribed concentration is arranged to a prescribed temperature. And the modified air is supplied from near bacterium colonization part at a flow rate necessary for making the single quality nutritious liquid to the prescribed concentration.【課題】 単質の養液を循環させて、葉菜類、果菜類、結球野菜類及び豆類などといったあらゆる品目の植物を、連作障害を発生させずに通年で同時に生産するための植物栽培システム、装置及び方法を提供する。【解決手段】 各々が植物を保持する栽培槽の内部を所定速度で流れる単質養液に、栽培槽の単質養液の溶存酸素濃度を所定濃度にするのに適した状態になるように空気を改質した改質空気を、所定温度にして、単質養液を前記所定濃度にするのに必要な流量で、バクテリア定着部の近傍から供給するようにしたことを特徴とする。【選択図】 図２
