Disclosed is a device for the subcortical injection of a substance into a plant, comprising a body (1), a substantially straight needle (3) pierced at its centre with a channel (4) opening via at least one hole (2) on the side wall of the needle and intended to penetrate into the plant, a store (5) communicating with the needle and containing the substance to be injected, a first actuator (6) capable of mobilising the needle so as to allow it to be inserted into the plant, a second actuator (7) capable of compressing the volume of substance present in the store so as to allow this substance to be injected, the device comprising a first force sensor (8) associated with the body allowing the bearing force applied by the device to the plant to be measured, a second force sensor (9) associated with the first actuator allowing the insertion force with which the needle is inserted into the plant to be measured； a third force sensor (10) allowing the pressurising force with which the volume of substance present in the store is pressurised to be measured, and at least one microcontroller that only allows the first actuator to be activated if the first force sensor detects a bearing force, that modulates the activation of the first actuator, and therefore the injection of the needle into the plant, depending on the insertion force measured by the second force sensor, and that modulates the compression of the volume of substance present in the store, and therefore the injection of this substance into the plant, depending on the force measured by the third force sensor.Un appareil pour l'injection sous-corticale d'une substance dans une plante comprenant un corps (1), une aiguille (3) sensiblement rectiligne et percée en son centre d'un canal (4) débouchant par au moins un trou (2) sur la paroi latérale de l'aiguille et destinée à pénétrer dans la plante, un réservoir (5) communiquant avec l'aiguille et renfermant la substance à injecter, un premier actionneur (6) apte à mobil
