PROBLEM TO BE SOLVED: To provide a plant cultivation apparatus which has a wide dynamic range and high detection sensitivity and is capable of accurately detecting ion concentration of a predetermined substance contained in nutritious liquid.SOLUTION: A plant cultivation apparatus comprises: a cultivation vessel in which plants are cultivated by nutritious liquid N a measurement cell (measurement part) 16 which has a light transmission region 17 contacting a flow channel 18 and the flow channel 18 through which the nutritious liquid N flows a light-emitting part 14 which emits measurement light L to be made incident to a boundary surface A between the light transmission region 17 and the flow channel 18 from the light transmission region 17 side a light receiving part 15 which receives measurement light L reflected on the boundary surface A to the light transmission region 17 side and a control part which detects ion concentration of a predetermined substance contained in the nutritious liquid N on the basis of absorption intensity of the measurement light L in the measurement cell 16.COPYRIGHT: (C)2016,JPO&INPIT【課題】広いダイナミックレンジ及び高い検出感度を有し、養液に含まれる所定物質のイオン濃度を精度良く検出することができる植物栽培装置を提供する。【解決手段】植物栽培装置は、養液Nによって植物が栽培される栽培槽と、養液Nが流れる流路18及び流路18に接する光透過領域17を有する測定セル(測定部)16と、光透過領域17側から光透過領域17と流路18との境界面Aに入射する測定光Lを発する発光部14と、境界面Aで光透過領域17側に反射した測定光Lを受ける受光部15と、測定セル16における測定光Lの吸収強度に基づいて、養液Nに含まれる所定物質のイオン濃度を検出する制御部と、を備えている。【選択図】図2
