PROBLEM TO BE SOLVED: To provide a hydroponic apparatus that can cultivate a plant from the stage at which only the underground part of the plant is present before the formation of the above ground part of the plant and can prevent the underground part of the plant from being irradiated with light during a necessary time period after the formation of the above ground part.SOLUTION: A hydroponic apparatus 10 comprises: a shading diaphragm mechanism 102 that constitutes a part of a partition unit 2 and can be changed from a state in which a gap exists between an inner peripheral surface of an opening 2a and a stem 20b to a state in which the inner peripheral surface of the opening 2a surrounds the stem 20b while contacting the outer peripheral surface of the stem 20b a driving unit 3 for driving the diaphragm mechanism 102 so as to change the state of the diaphragm mechanism 102 and a control unit 4 that controls, when the tip of the stem 20b extending from a tuber for nutrient storage 20a passes through the opening 2a, the drive unit 3 to make the diaphragm mechanism 102 change to the state in which the inner peripheral surface of the opening 2a surrounds the stem 20b while contacting the outer peripheral surface of the stem 20b.SELECTED DRAWING: Figure 1COPYRIGHT: (C)2017,JPO&INPIT【課題】地上部が形成される前の地下部のみが存在する段階から植物を栽培することができ、かつ、地上部が形成された後の必要な時期に地下部への光の照射を防止することができる水耕栽培装置を提供する。【解決手段】水耕栽培装置10は、仕切り部2の一部を構成し、開口部2aの内周面と茎20bとの間に隙間が存在する状態から開口部2aの内周面が茎20bの外周面に接触しながら茎20bを取り囲む状態へ変化し得る遮光性の絞り機構102と、絞り機構102の状態を変化させるように絞り機構102を駆動する駆動部3と、塊状栄養蓄積部20aから伸びる茎20bの先端が開口部2aを通過した場合に、駆動部3を制御することによって、開口部2aの内周面が茎20bの外周面に接触しながら茎20bを取り囲む状態へ絞り機構102を変化させる制御部4と、を備えている。【選択図】図1
