An apparatus for the subcortical injection of a substance into a plant comprising a body, a first force sensor associated with the body making it possible to measure the pressing force of the device on the plant, a substantially rectilinear needle and pierced in its center by a channel opening through at least one hole on the side wall of the needle and intended to penetrate into the plant, a reservoir communicating with the needle and containing the substance to be injected, a first actuator capable of mobilize the needle so as to allow its insertion into the plant, a second force sensor associated with the first actuator making it possible to measure the force of insertion of the needle into the plant, a second actuator able to compress the volume of substance present in the reservoir so as to allow injection of this substance, a third force sensor which makes it possible to measure the pressurizing force of the volume of substance present in the reservoir, and at least one microco controller which allows the activation of the first actuator only if the first force sensor detects a support force, which 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 which modulates the compression of the volume of substance present in the reservoir, and therefore of the injection of this substance into the plant, as a function of the force measured by the third force sensor. Figure for the abstract: Fig. 1 Un appareil pour l’injection sous-corticale d’une substance dans une plante comprenant un corps, un premier capteur d’effort associé au corps permettant de mesurer l’effort d’appui de l’appareil sur la plante, une aiguille sensiblement rectiligne et percée en son centre d’un canal débouchant par au moins un trou sur la paroi latérale de l’aiguille et destinée à pénétrer dans la plante, un réservoir communiquant avec l’aiguille et r
