Abstract: A device for the automatic and pulsed delivery of an irrigation liquid, which can be connected, at its upstream side, to a source liquid under a constant or substantially constant pressure, and at its downstream side, to a distribution network equipped with pressure-responding valves. These valves are capable of closing, during the step charging of the distribution system, at a pressure equal to, or substantially equal to, the liquid feed pressure, and of opening, during irrigation liquid expelling, when the pressure decreases under said value. The device comprises a Venturi device, fed with the same irrigation liquid, from whose region of constricted stream a duct is branched off, to transmit to a sliding member depressure generated by the Venturi.