In the article, to protect the garden from insect pests, theoretical studies have been carried out on the distribution of the electrical tension of video pulses inside insects. As the source of electromagnetic impulses, the electric current density is chosen, localized in the environment surrounding the biological object. For a given source of electromagnetic impulses, it is required to determine the electromagnetic field both within the biological object and in the outer space. These fields must satisfy the system of Maxwell's equations. To convert the non-stationary problem to the problem in the frequency domain, the desired electromagnetic fields inside and outside the biological object are represented as Fourier series. As a result of the transformations, the initial non-stationary problem of the interaction of a sequence of electromagnetic impulses with a biological object is reduced to the problem of diffraction of a harmonic electromagnetic field by a dielectric cylindrical scattered simulating a biological object. A direct solution of this problem is possible only by numerical methods. To simplify the problem, an explicit formula was obtained for the field averaged over the volume occupied by the biological object by the method of integral equations. The basis of integral equations is the representation of the electromagnetic field through vector potential functions and integral formulas of the theory of vector fields. As a result of the transformations, integral equations were obtained for the electric field strength inside and outside the biological object. The obtained expressions make it possible to determine the biotropic parameters of an impulse electromagnetic field for the destruction of insect pests in orchards. Creation on this basis of more effective mobile electrophysical installations allows to keep ecologically pure fruits and berries.