The Yukawa interaction Lagrangian is: $$ \mathcal{L}_{int}=-g\bar{\psi}(x)\psi(x)\phi(x)+h.c. $$ Is it possible to assign "charge" to any of the particles, like an electric charge? My first instinct would be no, but I am not sure if I can justify it - is it possibly because the strength of the interaction is dependent on three particles, rather than an even amount of them?
On the other hand, I know that the Yukawa interaction is supposed to be an approximation of the strong force - so perhaps a version of the color charge can be assigned?