A supply device for a single seeder via a flow of air from a main reservoir containing product to at least one auxiliary reservoir depending on its filling rate, each auxiliary reservoir being connected to the main reservoir by a respective leak-tight duct, the number of auxiliary reservoirs corresponding to the number of distributors of the single seeder. A regulating system is associated with each auxiliary reservoir and the regulating system has a sensor for detecting the level of product and a valve for regulating the flow of air in the corresponding auxiliary reservoir. A single seeder using a supply device according to the invention.
