The research is devoted to the study of the behavior of the generalizing magnetization vector in the seeds of agricultural crops under the action of longitudinal constant and transverse alternating magnetic fields by the method of nuclear magnetic resonance. Based on the theoretical studies, the value of the average magnetic susceptibility per unit volume of seed χ and the value of the magnetization vector were determined. For the system of microparticles of cells of plant origin, the average magnetic susceptibility per unit volume of seed is χ = 2.1 · 10-5, and the magnetization vector M=13.125 mA/m at a longitudinal constant magnetic field strength H = 625 A/m. When a weak transverse alternating magnetic field is superimposed on the frequency, the oscillation frequencies of the magnetization vectors M coincide with the field frequency, which is a condition for the occurrence of magnetic resonance. The longitudinal magnetization vector during the transition from the ground state to the excited state (resonant) describes a trajectory in the form of a spiral on the surface of the sphere. A mathematical model for a biological system taking into account the Earth's magnetic field is built. It is established that for the technology of pre-sowing treatment of seeds of agricultural crops, the inductor, which creates a constant magnetic field, must be located so that the vector of the constant magnetic field of the inductor coincides with the vector of the Earth's magnetic field. Keywords: bioenergetic resonance, pre-sowing treatment of crop seeds, direct magnetic field, alternating magnetic field, longitudinal and transverse relaxation