PROBLEM TO BE SOLVED: To suppress the rise in temperature of an irrigation liquid in a tube at the operation of a drip irrigation system, as well as to reduce the temperature of the irrigation liquid in the tube more quickly than a conventional system at the restart of drip irrigation system.SOLUTION: A drip irrigation tube has a tube comprising a first passage and a second passage, and an emitter. A first through hole is opened between the first passage and the second passage. A second through hole for discharging outside is opened in the second passage. Emitter comprises an intake part which takes irrigation liquid from the first through hole, a discharge part which discharges the irrigation liquid outside from the second through hole, an ejection part which ejects the irrigation liquid to the second passage, a first emitter passage which connects the intake part and the discharge part, a second emitter passage which connects the intake part and the ejection part, a decompression passage which reduces the pressure of the irrigation liquid taken in from the intake part and leads to the discharge part, and a flow control part which leads the irrigation liquid to the ejection part only when the pressure of the irrigation liquid exceeds a predetermined pressure.SELECTED DRAWING: Figure 2【課題】点滴灌漑システムの稼働時においてはチューブ内の灌漑用液体の温度上昇を抑制し、かつ点滴灌漑システムの再開時においてはチューブ内の灌漑用液体の温度を従来よりも速く低下させること。【解決手段】点滴灌漑用チューブは、第１流路および第２流路を含むチューブと、エミッタとを有する。第１流路および第２流路には、第１貫通孔が開口している。第２流路には、外部に吐出する第２貫通孔が開口している。エミッタは、第１貫通孔から灌漑用液体を取り入れる取水部と、第２貫通孔から灌漑用液体を外部に吐出する吐出部と、灌漑用液体を第２流路に排出する排出部と、取水部および吐出部を繋ぐ第１エミッタ流路と、取水部および排出部を繋ぐ第２エミッタ流路と、取水部から取り入れられた灌漑用液体の圧力を減圧させて、吐出部に導く減圧流路と、灌漑用液体の圧力が所定の圧力を超えたときのみ、灌漑用液体を排出部に導く流量調整部と、を含む。【選択図】図２
